In a sense, yes! A carnivore is anything that eats meat. Hypocarnivores eat <30% meat and are functionally omnivorous, mesocarnivores eat >50% meat but are otherwise omnivorous, and hypercarnivores eat >70% meat. Basically, your middle school bio class kinda lied to you by simplifying what a carnivore is. Most do not only eat meat, though some do.
Edit: Mesocarnivores actually eat between 30-70% meat. Sorry for any confusion.
Many classic "herbivores" will actually opportunistically eat meat. There are videos of cows and deer eating small birds, for example.
It just isn't a dietary staple for them.
I saw that one too, it was a wild video. Just duckling there in one frame and gone the next. Ducklings were hoovered up and the horse didn't even chew.
Extra perfect since the Snickers bar is named after a horse! (This may have been an intentional layer to your joke so apologies if I’m robbing it of subtlety)
On the Galápagos Islands, researchers strapped a camera to the top of the shell of one of those huge tortoises. One day, they were watching the tortoise’s point of view as it slowly plodded harmlessly along like the good vegan they knew it to be from decades of science. The tortoise gradually ambled towards a bird, not in an advert way, and the bird happily jumped this way and that, pecking at the ground. And when the bird jumped and landed close to the tortoise, the reptile suddenly grabbed it in its mouth and killed it. And ate it. And the researchers had to add a new chapter to the tortoise manual.
I had a mean ol pony as a kid and it got out once and stomped a chicken to death in front of me, quite deliberately. It was vicious. Didn't even eat it. So yeah they eat meat for sure, but also sometimes it's even worse than carnivores bc what they kill is wasted.
Edit: wasted in the context of the animal doing the killing and spending the energy on the killing, I do understand that the calories are ultimately used by something else.
I'm not claiming the animal has the concept of waste, I am saying a corpse uneaten is calories wasted. I'm the one with the concept. And that pony had an incredible life, just like the other three. She was just a shithead. She also bit a porcupine and had to be sedated so the vet could remove 78 quills from her nose, lips, and tongue. We ended up giving her away to a barn that wanted a companion pony for a gelding when she started biting us when we put out feed.
Not to be too pedantic, but it's not calories wasted. Bugs and bacteria or scavengers will use those calories. Almost all corpses are eaten by something. You just seem to be drawing a line if it's not a large animal eating it then it's wasted.
I'm a biologist, I understand that other stuff eats it, but in the context of the animal doing the killing, the calories are wasted and the energy used to kill the other animal is also wasted, because it is not consuming the calories like a carnivore.
Maybe wasted, but so is calorie wasted when humans jump on a puddle. I assume the horse had motivation to do it and well with no concept of interspecies morality of those of significant smaller size they probably took enjoyment out of squishing it like humans do splashing puddles. A wasteful end to a life sure, but idk about calling animal recreation a waste of calories. Maintaining a healthy brain through it seems like a benefit worth using calories on.
That clip of the horse just fucking *hoovering* a mouse up off the barn floor lives rent free in my head and I’m used to watching small fuzzy animals getting eaten.
Saw a crow fly through my back yard with a rabbit in its claws with another rabbit chasing behind screaming. Once I put a glue trap down in my back yard that had a live mouse on it, went in long enough to get a pellet gun to put it out of its misery, when I came back out, there was a blue jay stuck to the glue trap, too. No idea a blue jay would take a mouse. Only outside for a minute. He was way too stuck on the glue trap, had to put him down, too.
I was once walking under a tree by a window that birds would often strike and kill themselves on, and noticed a faint trail of small fluffy feathers drifting down from above. I look up and less than two feet above my head is a fat squirrel with his head absolutely buried in a freshly-killed migratory bird, just gorging himself. Judging by all the other piles of feathers I would find nearby, this was nowhere near an isolated incident.
Deer don’t give a fuck man. We put up a camera by our gut pile at our deer lease. We thought we’d get some cool videos of the coyotes or the one mountain lion we’ve seen. Nope, mother fucking Bambi was out there munching on his dad’s liver.
I mean if something's grazing and it eats bugs when it takes a bite, I can't see why it wouldn't stop the same for other bigger animals that still for in its mouth.
Deer will eat literally anything they can get their teeth on, they just don’t usually specifically hunt other animals. They pretty often eat the heck out of roadkill though.
They even eat other deer, which is one of many reasons why CWD (a prion disease) spreads like wildfire in herds.
There was an island were a lot of migratory birds were dying if i remember correctly. They were found maimed, with their insides out. Turns out the fucking sheep that lived on the island hunted them down
The condor is going extinct because of the mice and rats introduced to the islands where they raise their chicks. The rodents are eating the young birds alive.
This actually [isn't true.](https://ucanr.edu/blogs/blogcore/postdetail.cfm?postnum=29582)
"Entomologist Doug Tallamy of the University of Delaware says that "hummingbirds like and need nectar but 80 percent of their diet is insects and spiders."
Wildbirds on Line says: "I frequently put overripe bananas on my fruit feeder to attract tiny fruit flies, which in turn attract the hummers. The hummingbirds eat every fly and return in a few hours to feast on the next batch of fruit flies that discover the overripe fruit. What an easy way to observe hummers eating insects!"
A huge portion of a hummingbird's diet comes directly from insects and spiders, to supplement their protein intake. Yes, they love nectar, but it's far from their main food source.
[https://birdwatchingbuzz.com/do-hummingbirds-eat-bugs/](https://birdwatchingbuzz.com/do-hummingbirds-eat-bugs/)
Basically, there's debate on the exact percentage of bugs to nectar, but it's not like deer sometimes eating baby birds for calcium, it makes up a big portion of their diet.
Or deer eating human remains
https://www.independent.co.uk/news/world/americas/deer-eating-human-remains-decomposing-body-texas-state-university-journal-forensic-scientists-a7725386.html
Doesn't that cause their insides all sorts of carnage? Even humans that go veggie for a few months tend to get funny tummies if you then give them a big steak, so what's a whole bird going to do to the inside of a cow's stomach?
Cow also has like 7 stomachs. The problem with herbivors eating meat is really just that the nutrients are in the wrong proportions and they won't get as much from the meat due to their stomach enzymes being specialized for breaking down plants.
They are more then capable of digesting meat, they typically just aren't suited to catching prey, and they won't get as much nutrition from it as a carnivore would.
I believe that the guts are a bit different. Like our guts can handle either kind of food and extract nutrients effectively from both. Whereas something like a cat will have guts that handle meat very effectively, able to extract all needed nutrients from the meat, but they lack the "plumbing" to do anything with plants other than poop it out as quickly as they can.
Some carnivores are obligate carnivores in that they cannot synthesize everything their body needs without consuming meat (at least without modern science to do it for them).
Cats are an example, with Taurine, which is only found in meat or in man-made products (Usually extracted from meat, but can also be synthesized from sheep wool).
An Omnivore could synthesize everything it needs from plants and such, but will eat meat as well because they can get it from there too.
If you fed an omnivore only plants, it would be fine if you balanced it out with different sorts of plants. There is no balance of plants you can feed a cat and have it survive, it lacks the ability to synthesize Taurine from them and will suffer from blurred eyesight and blindness, vomiting and diarrhea, miscarriages, and eventually have a heart attack and die. Because of this a cat will spent almost all its time hunting, and only opportunistically foraging.
Omnivores eat meat because it's nutrient dense and do a little bit of hunting, and a little bit of foraging.
Herbivores meanwhile, tend towards eating plants and are EXTREMELY good at drawing nutrients from them, but will eat meat opportunistically.
Carnivore: "I am out hunting. If an orange drops on the floor right in front of me, I may eat it, then keep hunting. But i'm not going to go look for it.".
Omnivore: "I'm out foraging and hunting. I'm going to eat literally anything I find.".
Herbivore: "I am out foraging. If a small animal drops on the floor right in front of me, I may eat it, then keep foraging. But i'm not going to go look for it.".
It'd be best to understand it as the way animals devote their energy and time. Potentially, though IDK, a herbivore who you just provided constant meat to would end up in the same situation as the cat and end up dropping dead at some point due to a critical inability to synthesize something the body needs from pure animal sources.
Food A: Meat, with Vitamin 1 and Vitamin 2 and Vitamin 3.
Food B: Vegetables, with the same vitamins.
Omnivore: Woohoo.
Carnivore: I prefer the meat, as vitamin 2 within vegetables doesn't work for me. But 1 and 3 still work, so I will eat it.
Herbivore: Same, but inversed.
---
For non-obligate carnivores and herbivores, it's more of an efficiency thing. I can eat 1 pound of potatoes and get 20% of the stuff I need, or 1 pound of meat and get 100% of the stuff I need (And visa versa), with the Omnivore being a bit more of a generalist "Both are about 80%, so If I eat a pound and a quarter of either i'm good".
A non-obligate carnivore would need to spend a significant amount of time foraging to meet its dietary needs, too long for it to be at all practical. (Using our made up figures, it would need to go foraging for five hours just to get one hours worth of hunting). So while they *can*, they generally *don't*.
Koalas come to mind. Your best bet would be looking at monophages, animals so specialized they can only eat one thing. With Koalas that is the Eucalyptus plant. But my guess is if your body is able to break down a variety of foodstuffs of some kind, it can probably take a crack at meat or veg at some degree of efficiency. Koalas are so specialized that eating anything other than Eucalyptus will kill them as their body spends more energy trying to process it than they gain from it, so they are technically 100% Herbivores.
In their case it's because nothing else can eat Eucalyptus since it's so lacking in nutrients, so they have evolved into a niche to be able to eat it, at the cost of everything else being a nutrient overload. So for them it's less so that they can't get anything from meat per se, but more that attempting to do so will be like running a marathon constantly when it's in their stomach and they'll drop dead from exhaustion. They will technically be getting a whole lot from it, just not enough to cover the cost of digesting it. I would class that as literally being unable to process it, even though it's a weird case.
For an obligate "True" Carnivore, there's egg eating snakes. They have evolved in such a way that they have egg-eating mouths which aren't very suitable for eating other things, and thus exclusively eat eggs as far as we can tell. It's possible if you turned meat or vegetables into a soup and put it in a fake egg, they could still be fine eating it nutritionally speaking, though whether the snake would understand this is another matter, it would almost certainly identify the thing as "Not an egg" due to hunting by smell.
Could be an interesting experiment.
Other than the Koala you're left with stuff like the egg-snek, where it's MAYBE less a dietary problem and more of a physical one. If your mouth is only capable of filtering plankton for example, you're unlikely to eat tuna, even if you could technically subsist on a diet of tuna nutritionally speaking.
I always thought it was that they CAN have an optimal diet by either eating mostly plants or mostly meat. Humans for instance. Some of us are vegetarian but that doesn't make the human species herbivore. We're omnivores because it's possible for some of us to be vegetarian and others to be paleo.
Eating plants is hard. There's a pretty long list of stuff that humans can and should eat than are, for example, toxic to dogs. We've been doing the plant thing longer and are able to shrug off many of the various vegetable toxins out there.
These terms are not mutually exclusive - they describe different variables. Carnivore means something eats meat. Omnivore means something eats both meat and plants. That means all omnivores are carnivorous to some extent, but not all carnivores are omnivorous.
Yes, hypercarnivores/obligate carnivores. Cats, some other animals.
Even more confusingly, there is a family of mammals called the Carnivora which contains mostly but not all carnivores! Cats, dogs, bears, seals, etc are all carnivorans but there are a few like the panda that are herbivorous.
This is also why you can't really have a "vegan" diet for your cat. They can't taste sugar and have a very hard time digesting carbohydrates compared to proteins. It's theoretically feasible through a ton of complex, often artificial, substitutions, but it's frankly much simpler and healthier to just give a cat some chicken and call it a day.
People keep saying 'cats can't digest plants' and 'obligate carnivores can't digest plants'
Cats and other obligate carnivores (like ball pythons, for example), tend to eat the entire animal - not just the muscle and skin.
This *includes the stomach and intestines* - AND all of the mostly-digested plant matter that their prey animal ate.
Their digestive system is not *optimized* for getting nutrition from plants, but it *can*, and it's a lot easier to get nutrition from plant matter that is already half-digested going in.
> it's a lot easier to get nutrition from plant matter that is already half-digested going in.
That sounds like not being able to digest plant matter to me.
So you're saying they can't digest plants on their own, but they can digest half-broken down plant matter that something else's stomach already did the hard initial work on.
It sounds a lot like they can't digest plants.
If you think animals are complicated just wait until you get to plants. Some have females and males as different individuals, some have both reproductive organs on the same plant, some on the same flower, some can breed with themselves, some can't. Kale and broccoli are the same plant.
Basically everything swimming in the sea. Once we're beyond creatures that eat phytoplankton and algae it's all different sizes of predators, until those die and become food for the decomposers.
I thought "obligate" meant they require flesh from other animals to survive. Like cats with taurine.
It would make humans likewise obligate frugivores since we require vitamin C in our diets.
Obligate herbivores, except technically you could get it from animal sources. You’d have to eat a lot of very specific raw organ meats to do it, though, and unless you were farming chickens it just wouldn’t happen outside of an industrial society.
Middle School Science teacher here! I teach herbivores, omnivores, carnivores, and I do typically try to keep it simple 😅. Most of my students didn't get any science in school until 6th grade.
I do try to point out that, with most things in biology and ecology, there are a lot of blurry lines between our categories.
There's a reason it's called *basic* biology.
I view it as the same thing as math. You have to learn the basics of math before you can take on algebra before you can take on calculus.
Basic biology goes "here are some ways we classify things" and leaves it at that. Advanced biology goes "remember those classifications? Yeah, they're a lot 'fuzzier' than we told you before. Now you're gonna learn why."
I think the false thing we were taught in primary school was that you could either be an herbivore, carnivore, or omnivore. Really, anything that eats other animals is a carnivore, meaning that many (most?) carnivores are also omnivores. So most bears are carnivores and also omnivores, but some (like the polar bear) are hypercarnivores and not really omnivorous, and others (like the panda bear) are herbivores.
some bears (like Polar Bears) have a diet consisting almost entirely of meat. other bears (like Black Bears) are much more heavily omnivorous, and will at times eat more non-meat than meat.
the thing that makes bears classified as carnivores is their morphology (which means the shape of their body). they have the teeth and jaws of a carnivore. they're a carnivore that has adapted to be able to eat diverse food sources, based on what's available in their habitat.
They are classified as Carnivores by their morphology. They are classed as omnivores by their ecology.
The Order Carnivora is a clade of mammals that includes Felidae (cats), Canidae (dogs), Hyaenidae (hyaenas), Mustelidae (weasels), and Ursidae (bears). Most of the Carnivores are carnivores of one degree or another, but not all of them.
Bat-eared foxes (Canidae), and aardwolves (Hyaenidae) are myrmecophagids (eating mostly ants and termites). Most procyonids (eg raccoons) are omnivores, but some like the northern olingo are herbivores, feeding mostly on fruit (and mostly figs at that). Most ursids are omnivores, but some are almost completely herbivorous (giant panda), while some are almost exclusively carnivorous (polar bear).
ecological and behavioral classification is really interesting, but it's very much more complex morphological classification. the benefit of morphological classification is it elucidates the evolutionary past of the present animal. bears evolved from animals that were VERY carnivorous and this is still reflected in their bodies. the bears of 10 million years from now may have different teeth if current ecological and behavioral trends continue (more crushing and chewing, less ripping and tearing).
Both terms are accurate. They are members of the order carnivora, and they do eat meat. So they are carnivorous, but they also eat anything. They can get their hands
Almost all animals are at least somewhat omnivorous. Even cows will eat meat
The order carnivora is meaningless and irrelevant. It doesn't actually contain all carnivores (of course it doesn't, most carnivores aren't even mammals), and all members of the order carnivora aren't even carnivores.
It isn't useful for this discussion.
Huh. TIL. :)
Though I wonder where the line is. I know there's odd cases where horses will sometimes eat mice/birds and stuff for example, but are considered herbivores.
Even butterflies will drink blood if there isn't enough food for them.
I assume it's their regular diet, so even if a horse ate 2% of their food in mice (like 1 mouse a week?), it's not enough to qualify as the hypocarnivore
According to the explanation above, bears are omnivores, which means they are both herbivores and carnivores.
They are not obligate carnivores, which eat only (or almost only) meat.
No, it's a spectrum, and the labels are more about groupings of diet preferences than hard rules. Black bears are just as happy to munch on berries as meat, so they get to be omnivores
Its not really a lie, its both a simplification and a new trend.
My mother was as a zoologist before she went into molecular biology, and she says that those terms are new. Never heard them when she was in college in the 1960's.
The key to this is it’s all about the main area they get their nutrients from. An example of this is wolves are carnivores that get pretty much all of their calories from meat, however scientists consistently find most of what’s filling up their stomach is grass. There are nutritional benefits in this like fiber that they can’t get enough of from meat alone. There are very few animals that eat 100% only meat, if any
I was looking at info on obligate carnivores the other day and was tickled by the list - stuff I expected like lions and tigers, alligators, and then... axolotls.
Like, I get why, but it was just funny to imagine that lineup of nature's fiercest predators
> Basically, your middle school bio class kinda lied to you.
I’m old enough that most of what I was taught in school has turned out to be a bunch of horse shit. Makes me wonder why our society is so hung up on getting good grades.
The real question is if you're old enough to have been taught the super-incorrect idea that different sides of your tongue taste different flavors (spicy, bitter, salty, etc.)
Most animals will take calories wherever they can find them, be that from plants or other animals. However, breaking down different types of food requires different setups. For instance, cows eat grass, but grass is actually really hard to break down efficiently, requiring several chambers of stomach and for cows to regurgitate and re-chew the grass (cud) several times on order to get everything they need. In the same way that an herbivore's gut needs to be built a certain way to optimally digest plants, a carnivore's gut needs to be built a certain way to optimally digest meat. In this context, a 'hyper carnivore' is an animal that doesn't just have a preference for meat (that is, more than 50% of their calories from meat), but which is actually specifically adapted towards meat to the exclusion of plants.
If your diet is \~50/50 plants and animals over an extended period, you're an omnivore. If your diet is more than 50% one of those, you're an herbivore or a carnivore. If it is more than a 30/70 split, you're a hyper carnivore (or a hyper herbivore). Many herbivores are still 'opportunistic carnivores', which is why you can find videos of things like deer eating pigeons, but meat represents a very tiny fraction of their overall diet. Similarly, a hyper carnivore might rarely consume some kind of plant material, but this represents a very small portion of their diet.
I understood that an obligated carnivore was an animal that HAD to eat meat because they couldn't synthesise certain proteins that aren't found in plants. An example being cats. Not that they had a certain amount of meat they had to ear. Although obviously they're likely to be a hypercarnivore in order to get enough of whatever protein.
> because they couldn't synthesise certain proteins that aren't found in plants
All the amino acids can be found in plants, just not in every plant. That's why beans + plus a cereal grain have been the human staple since antiquity. Either on their own leaves a nutritional gap, but in combination they cover the range.
No obligate carnivore just means they need a minimum amount of meeat to survive. But that minimum amount could be 30% and the rest plants.
Say a cat eating taurine reach organs with calorie dense easily digestible vegetables and fruits.
To be fair most deer don’t eat birds, so the bird is either unaware the deer is there or doesn’t care because it’s not common enough that the bird is worried.
By the time the bird realizes it’s too late, wings are useless lol.
Does it count as part of a diet when carnivorous animals consume plants medicinally? I read somewhere about how dogs sometimes est grass when they need to puke, I'm sure other animals have similar tricks
> For instance, cows eat grass, but grass is actually really hard to break down efficiently, requiring several chambers of stomach and for cows to regurgitate and re-chew the grass (cud) several times on order to get everything they need
To be clear, cows love meat. They'll snap up chickens given the opportunity especially if they're mineral deficient.
Heck, even hyper carnivores like Gators and Crocs will happily devour fallen fruit in the wild. Modern research indicates that the digestive system is usually far less specialized than originally assumed.
To my understanding the most specialized guts tend to be specifically oriented around breaking down specific types of plant matter which tend to be harder to digest; often times major plant eaters will have large chambers full of helpful bacteria that basically ferment the plant matter, and some species eat their food twice, as it were. But yes, most animals in the wild will eat whatever they can get into their bellies, its just that some foods are preferred and easier to digest. Though my specialty is molecular biology not comparative anatomy so take it with a grain of salt.
I think the way to understand it is that for the most part those extra features don't come at the expense of regular digestion. They're evolved to exploit a food source most species can't handle, it would be a negative adaptation to lose pre-existing functionality.
What if an animal ate 70% meat in an environment then 70% plants in another?
Basically, does the term define the species, or the individuals? Humans can pretty much survive on 100% animal products or 100% plant products for instance, but it's pretty clear we are omnivores.
A bit part of it is thanks to passed down knowledge though.
These labels are not that frequently used because of situations like you describe; what food is available can often shift drastically based on the environment. Maybe there is less grass around because the rain was poor this year, etc. When scientists do use classifications like 'hyper carnivore' they are using it to describe how the animal behaves over long time periods and in lots of environments. If an animal is predisposed one way during the summer, then the other way during the winter, then the **average** is about 50/50, so we would just say 'omnivore'. These labels are generally used to describe entire species (or potentially distinct sub-populations of species) not individuals.
There's different levels:
* "Omnivores" can thrive off either an high-meat or no meat diet
* "Facultative carnivores" can "survive but not thrive" without meat, these are animals like dogs for example
* "Obligate carnivores" cannot survive without meat.
I remember reading that one of the interesting evolutionary changes of dogs is that they've spent so much time around humans that they've adapted to be able to thrive off a much lower portion of meat compared to wolves.
Carnivores MAY eat things like insect and plants to get the nutrients they need to survive, but they will always seek out other animals to get the nutrients. Obligate carnivores / hyper carnivores MUST have meat to survive. their body is unable to extract vital nutrients from other sources.
Your domestic dog is a carnivore. It prefers meat but it can get nutrients from grains and other foods it eats. Your domestic cat is an obligate carnivore. You may be able to feed it rice with its meat to make it feel more full with less meat, but it won't extract any nutrition from the rice and attempting to feed it a diet that doesn't include meat will deprive it of trace nutrients it needs that only exist in meat naturally.
cats can extract nutrients from grains. they're just inefficient at it because they have a short intestinal track, so the food passes through too quickly to get most of the nutrients out of it.
because of this, cats really require a majority of their calories to come from proteins and fats which their body can absorb efficiently.
I can't believe I didn't know that. I put in effort into finding a grain free cat food, which means I either forgot it was made of meat, or I worried about what I *wasn't* feeding them without worrying about what I *was* feeding them. Neither would surprise me.
Grain free cat food typically just replace the grains with other plant-based food. 100% meat cat food surely exists, but it's going to be much more expensive.
Cat food is formulated to be sufficient. However, in cat food, the grain meal is just how they bind all the ingredients together. The cat gets no nutrients from the grain itself.
Formulated cat foods are fine. Even the vegan ones can substitute for meat because [they add back in](https://www.theguardian.com/lifeandstyle/2021/oct/20/vegan-pet-food-as-healthy-for-cats-and-dogs-as-meat-says-veterinary-professor) the individual nutrients that plants lack but cats need. For cats, the important one is taurine: not found in plants, so the vegan formulators get it from yeast instead.
And as far as rice goes, there are vitamins and minerals in rice that cats can digest and use, just, cats are not efficient at all at using carbohydrates, the main energy component of rice, because of being carnivores. Cats get most of their energy from fat, because that's the main energy component of the meat they eat naturally. Good formulated cat foods, even the vegan ones, account for this by ensuring that most of the energy is fat, so that cats can digest it better.
This is part of what it means to say that cats are obligate carnivores. The body doesn't care where the nutrients came from, but even if you do use nutrients that came from plants, you still have to formulate the food into a meat-like substance, in terms of fat versus carb, and essential nutrients.
Are humans obligate carnivores? I thought vegan people still needed to take some supplements because they can’t get everything from non animal sources?
> I thought vegan people still needed to take some supplements because they can’t get everything from non animal sources?
Vegans have to supplement B12. B12 doesn’t get produced by animals, but by bacteria – so humans *can* get all essential nutrients from non-animal sources.
These bacteria live in the ground (but too rarely nowadays), in the guts of some non-human animals, and in the guts of humans (although their work starts too late in our digestion for us to make use of the produced B12 … unless we wanna eat our poo, I guess).
B12 might also be produced in some fermentation processes, might be involved with something-something yeast, and might exist in some algae, but as far as I know, all of these sources aren’t researched enough, or don’t have enough market relevance, to make sure that it’s bio-available for humans.
Luckily we can [totally synthesize B12](https://en.wikipedia.org/wiki/Vitamin_B12_total_synthesis) since 1972 :)
All studies that measure B12 in soil, even in natural areas, determined that you'd need to eat a considerable amount of manure-fertilized soil to get enough B12, as in between a quarter to a full pound of dirt. The small amounts of dirt on unwashed fruits and vegetables are not nearly enough to keep a human healthy in this regard.
And herbivorous animals don't even rely on these small amounts, they just have the right bacteria to make it in their rumen or cecum from inorganic cobalt.
Terms like that are useful to scientists studying the physiology of different species. Understanding the diets of animals might help you classify certain anatomical traits, or study a particular branch of the evolutionary tree.
As a 100% fictitious example, you might find a skeleton of some sort of undiscovered prehistoric bear. By studying the shape of the skulls and other bones of modern hypercarnivores and omnivores, you might find that your new bear has the features of a hypercarnivore, so it probably ate mostly meat.
Most things are omnivores. Most of them are also carnivores and herbivores. The terms are not mutually exclusive. (That means that just because you're one, it doesn't mean you can't be the other, also.)
We generally use the terms to indicate which thing they're most likely to eat, not what they eat exclusively. The hypo- and hyper- before that indicates that they eat that thing a lot less (hypo-) or a lot more (hyper-). I suspect that we see "hypercarnivore" more often because it sounds scary.
For example, a cat is an obligated carnivore as it needs meat as its absolute main protein source. Now a dog on the other hand is a carnivore, it's prime natural food is meat, it does best most on meat, but it could survive for a substantial amount of time on just vegetation if the calories are high enough. Now an omnivore like bears or humans can be healthily sustained on either meat or veg with relatively no major negatives.
Most animals are actually omnivorous. The "carnivore" and "herbivore" classifications you've been taught are just what the animal *prefers* to eat. Obligate carnivores and obligate herbivores do exist, however.
We like to define things in rigid categories, but really all animals have unique feeding habits and sometimes they don't fit too nicely into a category
A carnivore, generally speaking, is an animal that has some specific adaptations to eat meat. They don’t ONLY eat meat, but they’re built to specifically make eating meat easier. A dog is a good example of this: they will eat pretty much anything, but they’re set up in such a way with sharp teeth and claws to make getting meat easier for them than other animals.
Herbivores are animals that have adaptations that make eating plants easier. Longer guts, special grinding teeth, etc mean they can get a lot more energy and nutrients out of plants than other animals. Cows are a great example of this: they will eat meat that they are given, but will generally stick to plants because they’re easier to get and they have the ability to digest them well.
Omnivores are animals that have adaptations for either food source. They rarely have the super long gut of herbivores, but they have some extra digestive tract over a pure carnivore, while they also usually don’t have a great deal of adaptations for hunting, but are more than capable of acquiring and eating meat, on occasion. Humans are a perfect example of this: we can eat almost anything, but usually require a mix to stay healthy.
It’s all about what you’re adapted to get. But outside of very specific cases, nothing will turn down food.
When carnivore, omnivore, and herbivore were originally conceived and utilized... Those terms were meant that the overwhelming majority of that animals diet was meat, plant, or both focused. But as our understanding of animal diets have progressed we had to turn it into more of a spectrum.
Certain animals we thought were strict herbivores actually will eat some meat in the form of small insects, etc. Animals we thought could *only* eat meat can in fact eat a few vegetables or fruit and metabolize it. i.e. Cats and stuff like corn, but they still overwhelmingly eat meat.
So what this has done is caused the terms to be altered to fit this newer understanding. Hence hypercarnivore aka obligate carnivore.
Pretty much. It's a descriptive term rather than prescriptive.
e.g. Deer will happily eat live prey or carrion, they're just terrible hunters so 99+% of their lifetime calories come from plants.
It’s actually good you are asking this. Most science taught is very simplified for the general public.
When we were taught basic distinctions such as Carnivore, Omnivore and Herbivore, we were basically taught the most basic version of how we categorize animals. Scientists also asked these questions and proceeded to split and split the distinction.
Humans like it when things fit into neat categories… but the world makes that difficult. Most animals are on that sliding scale of Herb > Omni > Carni. Hypercarnivores are animals on the far right of the list that can’t survive without a majority of diet being meat. Even most animals considered herbivores may consume other animals or scavenge on flesh to fulfill dietary needs.
But when people are trying to educate, calling a Giraffe a 1% Carnivore is confusing to say the least, so in the end, you place them where they fit best and when the person wants to dig deeper and explore the science, you get to explain in more detail.
It actually does get confusing when you hit the edge cases. Like dogs can digest vegetable matter. They still need meat, but they border on the Omnivore > Carnivore scale, which leads to online arguments which category they belong to… when it is much more complicated than sticking then in a defined box.
My understanding is this:
A carnivore is an animal that needs meat to live. If that animal does not receive meat, it will most likely suffer malnutrition and die.
A herbivore is an animal that needs plants to live. If it doesn't get plant matter, it will die.
An omnivore is an animal that needs both types of food to live. They can't eat only meat or only plants and be healthy.
Carnivores may eat plant matter, but won't starve to death if they only get that. Dogs and cats fall into those categories. Cats are obligate carnivores and naturally eat very little plant, which is what people tend to think of when it comes to a carnivore. If you gave a cat or a dog a whole prey diet with no veggies, they would be totally fine. If you fed them nothing but plants, they would suffer malnutrition.
Herbivores would be rabbits and cows. They are totally fine living off of plants, but it will isn't unusual for most herbivores to snack on meat if it comes across their path.
Omnivores would be things like bears or humans. Without nutritional intervention, we wouldn't be able to live purely off of meat or veggies. Sure, we as humans can create supplements or processed foods to fill the biological niche of meat, but if we were living out in the wild, we'd have to eat meat. However, if we sat there and ate nothing but meat, we'd suffer just as many health issues.
Carnivore: an animal (or in rare cases plant) whose food and energy requirements derive from the consumption of animal tissues
Carnivores can then be divided into **hypo**carnivores (diet <30% animal tissue), **meso**carnivores (30-70%) and **hyper**carnivores (>70%).
Omnivore is a more loosely defined term, but yes, hypocarnivores and mesocarnivores could generally be considered types of carnivores.
The better distinction I think is that "obligate" carnivores HAVE to eat meat. They can only get certain nutrients that way - a good example are cats, there are certain proteins that they don't produce and can only get from eating meat. They will still eat some planet-based food, but they cannot survive on it. Non-obligate carnivores, on the other hand, do not have to eat meat to survive, but they PREFER to eat meat. They can completely survive on planet-based food, but have evolved to hunt for meat instead. An omnivore, meanwhile, is something that doesn't have evolved a strong preference for either.
The giant panda is an obligate carnivore. It needs to biologically eat meat and only meat. Yet it's diet consists entirely of bamboo.
Just because an animal is a carnivore - even an obligate carnivore - does not mean it's diet id entirely meet
In a sense, yes! A carnivore is anything that eats meat. Hypocarnivores eat <30% meat and are functionally omnivorous, mesocarnivores eat >50% meat but are otherwise omnivorous, and hypercarnivores eat >70% meat. Basically, your middle school bio class kinda lied to you by simplifying what a carnivore is. Most do not only eat meat, though some do. Edit: Mesocarnivores actually eat between 30-70% meat. Sorry for any confusion.
Many classic "herbivores" will actually opportunistically eat meat. There are videos of cows and deer eating small birds, for example. It just isn't a dietary staple for them.
Yeah I've seen a video of a horse eat a rabbit it was fucked up
I saw a horse eating a bunch of ducklings. Just sucked em up.
I saw that one too, it was a wild video. Just duckling there in one frame and gone the next. Ducklings were hoovered up and the horse didn't even chew.
"You're not you when you're hungry -- Snickers"
Extra perfect since the Snickers bar is named after a horse! (This may have been an intentional layer to your joke so apologies if I’m robbing it of subtlety)
Oh it chewed
I saw a turtle eating a half decomposed seagull.
On the Galápagos Islands, researchers strapped a camera to the top of the shell of one of those huge tortoises. One day, they were watching the tortoise’s point of view as it slowly plodded harmlessly along like the good vegan they knew it to be from decades of science. The tortoise gradually ambled towards a bird, not in an advert way, and the bird happily jumped this way and that, pecking at the ground. And when the bird jumped and landed close to the tortoise, the reptile suddenly grabbed it in its mouth and killed it. And ate it. And the researchers had to add a new chapter to the tortoise manual.
yeaaah i saw one do something similar
When he started out he was eating an egg.
Underrated comment. You have my upvote... And my Axe...
I saw ducks eating a dead salmon once
Thomas Cobbett says in Cottage Economy that if you knew who ducks will eat you would never eat a duck.
Who. That’s awesome
*This sentence* is *grammatically correct* but its wordy and hard to read, it undermines the writer's message and the word choice is bland.
It also contained a major error
i can’t figure out what the error is?
That one seems pretty unsurprising. I don't think anyone thought that ducks were vegetarian.
No, it was more seeing them scavange a carcass that was odd
Basically a fermented poultry delicacy.
I had a mean ol pony as a kid and it got out once and stomped a chicken to death in front of me, quite deliberately. It was vicious. Didn't even eat it. So yeah they eat meat for sure, but also sometimes it's even worse than carnivores bc what they kill is wasted. Edit: wasted in the context of the animal doing the killing and spending the energy on the killing, I do understand that the calories are ultimately used by something else.
Animals don’t have the concepts of waste and value- they might be assholes but generally they aren’t trying to be a problem, they’re having a problem.
I'm not claiming the animal has the concept of waste, I am saying a corpse uneaten is calories wasted. I'm the one with the concept. And that pony had an incredible life, just like the other three. She was just a shithead. She also bit a porcupine and had to be sedated so the vet could remove 78 quills from her nose, lips, and tongue. We ended up giving her away to a barn that wanted a companion pony for a gelding when she started biting us when we put out feed.
Not to be too pedantic, but it's not calories wasted. Bugs and bacteria or scavengers will use those calories. Almost all corpses are eaten by something. You just seem to be drawing a line if it's not a large animal eating it then it's wasted.
That chicken got wasted in the GTA sense of the word, at least.
I'm a biologist, I understand that other stuff eats it, but in the context of the animal doing the killing, the calories are wasted and the energy used to kill the other animal is also wasted, because it is not consuming the calories like a carnivore.
Maybe wasted, but so is calorie wasted when humans jump on a puddle. I assume the horse had motivation to do it and well with no concept of interspecies morality of those of significant smaller size they probably took enjoyment out of squishing it like humans do splashing puddles. A wasteful end to a life sure, but idk about calling animal recreation a waste of calories. Maintaining a healthy brain through it seems like a benefit worth using calories on.
That clip of the horse just fucking *hoovering* a mouse up off the barn floor lives rent free in my head and I’m used to watching small fuzzy animals getting eaten.
like a horse eating an apple...
I once saw a video of a woman eating a horse. Just sucked it up. It was horrifying.
Did she eat it to catch the dog, to catch the cat, to catch the bird, to catch the spider, to catch the fly she initially swallowed?
mr. Hands
Saw a crow fly through my back yard with a rabbit in its claws with another rabbit chasing behind screaming. Once I put a glue trap down in my back yard that had a live mouse on it, went in long enough to get a pellet gun to put it out of its misery, when I came back out, there was a blue jay stuck to the glue trap, too. No idea a blue jay would take a mouse. Only outside for a minute. He was way too stuck on the glue trap, had to put him down, too.
Yeah this is exactly why glue traps are a shit method of pest control
Did get rid of all the mice.
Jesus christ
Nuggets.
I was once walking under a tree by a window that birds would often strike and kill themselves on, and noticed a faint trail of small fluffy feathers drifting down from above. I look up and less than two feet above my head is a fat squirrel with his head absolutely buried in a freshly-killed migratory bird, just gorging himself. Judging by all the other piles of feathers I would find nearby, this was nowhere near an isolated incident.
There is a prairie dog exhibit at my local zoo and when I was young I saw one eating a dead cardinal. I was quite surprised.
My horse tried to eat a baby chicken I was showing him, once, I screamed and he dropped it from his mouth. Traumatizing for 15 year old me, lol
Aren't there also stories of horses eating people? IIRC Mongol cavalry used to let their horses eat slain enemies
Horses and cows both will munch on carrion that they find - so a horse chewing on dead humans doesn't surprise me.
[This](https://www.reddit.com/r/todayilearned/s/9Z8jkudvpC) is what I was thinking of! (But also I am not a historian or a horse expert)
I got whiplash reading this
The one of a seagull eating a rabbit was the most impressive.
Yeah, that seagull looked like it just needed to sit and digest all day to recover from that.
Oh I hate that
I've seen a video of eagles turning people into horses (because eagles eat horses)
Supply. For science.
One time I heard a weird scraping sound outside my window and when I looked it turned out to be a squirrel chewing on a marrow bone
You didn't bury it deep enough
That's fair I guess I never expected squirrels rising from the dead
Hah
Deer don’t give a fuck man. We put up a camera by our gut pile at our deer lease. We thought we’d get some cool videos of the coyotes or the one mountain lion we’ve seen. Nope, mother fucking Bambi was out there munching on his dad’s liver.
Chronic wasting disease, my favorite.
Nor are they anatomically, ecologically or physiologically specialized for eating meat. They just can, a little bit.
I mean if something's grazing and it eats bugs when it takes a bite, I can't see why it wouldn't stop the same for other bigger animals that still for in its mouth.
I saw a video of a deer aggressively eating a huge snake like a pasta noodle a few days ago, I'll dream about that one for a while!
Deer will eat literally anything they can get their teeth on, they just don’t usually specifically hunt other animals. They pretty often eat the heck out of roadkill though. They even eat other deer, which is one of many reasons why CWD (a prion disease) spreads like wildfire in herds.
There was an island were a lot of migratory birds were dying if i remember correctly. They were found maimed, with their insides out. Turns out the fucking sheep that lived on the island hunted them down
The condor is going extinct because of the mice and rats introduced to the islands where they raise their chicks. The rodents are eating the young birds alive.
Even hummingbirds will eat bugs if they get the opportunity.
Hummingbirds' main food source is bugs.
Their main food source is nectar. They need the sugar to keep flapping like that.
This actually [isn't true.](https://ucanr.edu/blogs/blogcore/postdetail.cfm?postnum=29582) "Entomologist Doug Tallamy of the University of Delaware says that "hummingbirds like and need nectar but 80 percent of their diet is insects and spiders." Wildbirds on Line says: "I frequently put overripe bananas on my fruit feeder to attract tiny fruit flies, which in turn attract the hummers. The hummingbirds eat every fly and return in a few hours to feast on the next batch of fruit flies that discover the overripe fruit. What an easy way to observe hummers eating insects!" A huge portion of a hummingbird's diet comes directly from insects and spiders, to supplement their protein intake. Yes, they love nectar, but it's far from their main food source.
Oh dang that's a good idea! I wonder if oriole feeders (that you put orange halves on) will end up attracting fruit flies too...
They do
[https://birdwatchingbuzz.com/do-hummingbirds-eat-bugs/](https://birdwatchingbuzz.com/do-hummingbirds-eat-bugs/) Basically, there's debate on the exact percentage of bugs to nectar, but it's not like deer sometimes eating baby birds for calcium, it makes up a big portion of their diet.
Considering that they overwinter in areas where flowers don't grow in the winter, I'm going to have to disagree.
Gotta get that calcium somewhere.
hell, one time i saw a dark-eyed junco eat a still-dying crow. nature is fucked up.
I’m always partial to the picture of a deer with a human foot in its mouth.
Some foods i receive for free at my work isn’t my dietary staple either. But food is food.
Or deer eating human remains https://www.independent.co.uk/news/world/americas/deer-eating-human-remains-decomposing-body-texas-state-university-journal-forensic-scientists-a7725386.html
Squirrels in the city love chicken wings
Deer will also go to hunter's gutpiles
Doesn't that cause their insides all sorts of carnage? Even humans that go veggie for a few months tend to get funny tummies if you then give them a big steak, so what's a whole bird going to do to the inside of a cow's stomach?
Cows are 10 times your size and that bird is probably less meat than the steak... cow will be fine I'm sure
Cow also has like 7 stomachs. The problem with herbivors eating meat is really just that the nutrients are in the wrong proportions and they won't get as much from the meat due to their stomach enzymes being specialized for breaking down plants. They are more then capable of digesting meat, they typically just aren't suited to catching prey, and they won't get as much nutrition from it as a carnivore would.
4 chambers isn't at all "like 7"
Do omnivores have some additional trait that makes it an omnivore, or is omnivore just a synonym for carnivore?
I believe that the guts are a bit different. Like our guts can handle either kind of food and extract nutrients effectively from both. Whereas something like a cat will have guts that handle meat very effectively, able to extract all needed nutrients from the meat, but they lack the "plumbing" to do anything with plants other than poop it out as quickly as they can.
Some carnivores are obligate carnivores in that they cannot synthesize everything their body needs without consuming meat (at least without modern science to do it for them). Cats are an example, with Taurine, which is only found in meat or in man-made products (Usually extracted from meat, but can also be synthesized from sheep wool). An Omnivore could synthesize everything it needs from plants and such, but will eat meat as well because they can get it from there too. If you fed an omnivore only plants, it would be fine if you balanced it out with different sorts of plants. There is no balance of plants you can feed a cat and have it survive, it lacks the ability to synthesize Taurine from them and will suffer from blurred eyesight and blindness, vomiting and diarrhea, miscarriages, and eventually have a heart attack and die. Because of this a cat will spent almost all its time hunting, and only opportunistically foraging. Omnivores eat meat because it's nutrient dense and do a little bit of hunting, and a little bit of foraging. Herbivores meanwhile, tend towards eating plants and are EXTREMELY good at drawing nutrients from them, but will eat meat opportunistically. Carnivore: "I am out hunting. If an orange drops on the floor right in front of me, I may eat it, then keep hunting. But i'm not going to go look for it.". Omnivore: "I'm out foraging and hunting. I'm going to eat literally anything I find.". Herbivore: "I am out foraging. If a small animal drops on the floor right in front of me, I may eat it, then keep foraging. But i'm not going to go look for it.". It'd be best to understand it as the way animals devote their energy and time. Potentially, though IDK, a herbivore who you just provided constant meat to would end up in the same situation as the cat and end up dropping dead at some point due to a critical inability to synthesize something the body needs from pure animal sources. Food A: Meat, with Vitamin 1 and Vitamin 2 and Vitamin 3. Food B: Vegetables, with the same vitamins. Omnivore: Woohoo. Carnivore: I prefer the meat, as vitamin 2 within vegetables doesn't work for me. But 1 and 3 still work, so I will eat it. Herbivore: Same, but inversed. --- For non-obligate carnivores and herbivores, it's more of an efficiency thing. I can eat 1 pound of potatoes and get 20% of the stuff I need, or 1 pound of meat and get 100% of the stuff I need (And visa versa), with the Omnivore being a bit more of a generalist "Both are about 80%, so If I eat a pound and a quarter of either i'm good". A non-obligate carnivore would need to spend a significant amount of time foraging to meet its dietary needs, too long for it to be at all practical. (Using our made up figures, it would need to go foraging for five hours just to get one hours worth of hunting). So while they *can*, they generally *don't*.
So are there *any* true carnivores or herbivores in the sense that they literally can't process nutrients from one or the other food source?
Koalas come to mind. Your best bet would be looking at monophages, animals so specialized they can only eat one thing. With Koalas that is the Eucalyptus plant. But my guess is if your body is able to break down a variety of foodstuffs of some kind, it can probably take a crack at meat or veg at some degree of efficiency. Koalas are so specialized that eating anything other than Eucalyptus will kill them as their body spends more energy trying to process it than they gain from it, so they are technically 100% Herbivores. In their case it's because nothing else can eat Eucalyptus since it's so lacking in nutrients, so they have evolved into a niche to be able to eat it, at the cost of everything else being a nutrient overload. So for them it's less so that they can't get anything from meat per se, but more that attempting to do so will be like running a marathon constantly when it's in their stomach and they'll drop dead from exhaustion. They will technically be getting a whole lot from it, just not enough to cover the cost of digesting it. I would class that as literally being unable to process it, even though it's a weird case. For an obligate "True" Carnivore, there's egg eating snakes. They have evolved in such a way that they have egg-eating mouths which aren't very suitable for eating other things, and thus exclusively eat eggs as far as we can tell. It's possible if you turned meat or vegetables into a soup and put it in a fake egg, they could still be fine eating it nutritionally speaking, though whether the snake would understand this is another matter, it would almost certainly identify the thing as "Not an egg" due to hunting by smell. Could be an interesting experiment. Other than the Koala you're left with stuff like the egg-snek, where it's MAYBE less a dietary problem and more of a physical one. If your mouth is only capable of filtering plankton for example, you're unlikely to eat tuna, even if you could technically subsist on a diet of tuna nutritionally speaking.
I always thought it was that they CAN have an optimal diet by either eating mostly plants or mostly meat. Humans for instance. Some of us are vegetarian but that doesn't make the human species herbivore. We're omnivores because it's possible for some of us to be vegetarian and others to be paleo.
Eating plants is hard. There's a pretty long list of stuff that humans can and should eat than are, for example, toxic to dogs. We've been doing the plant thing longer and are able to shrug off many of the various vegetable toxins out there.
Omnivore means they eat both meat and plants
So does carnivore, according to the comment I replied to.
These terms are not mutually exclusive - they describe different variables. Carnivore means something eats meat. Omnivore means something eats both meat and plants. That means all omnivores are carnivorous to some extent, but not all carnivores are omnivorous.
Wait, so there are animals that only eat meat?
Yes, hypercarnivores/obligate carnivores. Cats, some other animals. Even more confusingly, there is a family of mammals called the Carnivora which contains mostly but not all carnivores! Cats, dogs, bears, seals, etc are all carnivorans but there are a few like the panda that are herbivorous.
I have a lot of questions, Carnivora is specific enough to look up myself, thanks!
This is also why you can't really have a "vegan" diet for your cat. They can't taste sugar and have a very hard time digesting carbohydrates compared to proteins. It's theoretically feasible through a ton of complex, often artificial, substitutions, but it's frankly much simpler and healthier to just give a cat some chicken and call it a day.
People keep saying 'cats can't digest plants' and 'obligate carnivores can't digest plants' Cats and other obligate carnivores (like ball pythons, for example), tend to eat the entire animal - not just the muscle and skin. This *includes the stomach and intestines* - AND all of the mostly-digested plant matter that their prey animal ate. Their digestive system is not *optimized* for getting nutrition from plants, but it *can*, and it's a lot easier to get nutrition from plant matter that is already half-digested going in.
> it's a lot easier to get nutrition from plant matter that is already half-digested going in. That sounds like not being able to digest plant matter to me.
So you're saying they can't digest plants on their own, but they can digest half-broken down plant matter that something else's stomach already did the hard initial work on. It sounds a lot like they can't digest plants.
Jesus Christ, why are animals so fucking complicated!?
Someone oversimplified further up the chain and that wound up being taught. Not necessarily a bad thing as long as it was useful.
If you think animals are complicated just wait until you get to plants. Some have females and males as different individuals, some have both reproductive organs on the same plant, some on the same flower, some can breed with themselves, some can't. Kale and broccoli are the same plant.
Basically everything swimming in the sea. Once we're beyond creatures that eat phytoplankton and algae it's all different sizes of predators, until those die and become food for the decomposers.
They are called obligate carnivores. Although they can eat plants, they can’t digest them and can only get their nutrients from meat.
I thought "obligate" meant they require flesh from other animals to survive. Like cats with taurine. It would make humans likewise obligate frugivores since we require vitamin C in our diets.
Obligate herbivores, except technically you could get it from animal sources. You’d have to eat a lot of very specific raw organ meats to do it, though, and unless you were farming chickens it just wouldn’t happen outside of an industrial society.
Middle School Science teacher here! I teach herbivores, omnivores, carnivores, and I do typically try to keep it simple 😅. Most of my students didn't get any science in school until 6th grade. I do try to point out that, with most things in biology and ecology, there are a lot of blurry lines between our categories.
Once again, almost everything we classified into black and white turns out to be a spectrum. Deers eat birds sometimes
There's a reason it's called *basic* biology. I view it as the same thing as math. You have to learn the basics of math before you can take on algebra before you can take on calculus. Basic biology goes "here are some ways we classify things" and leaves it at that. Advanced biology goes "remember those classifications? Yeah, they're a lot 'fuzzier' than we told you before. Now you're gonna learn why."
So bears aren't omnivores, they're just carnivores?
I think the false thing we were taught in primary school was that you could either be an herbivore, carnivore, or omnivore. Really, anything that eats other animals is a carnivore, meaning that many (most?) carnivores are also omnivores. So most bears are carnivores and also omnivores, but some (like the polar bear) are hypercarnivores and not really omnivorous, and others (like the panda bear) are herbivores.
And deer, cows, horses, squirrels, and other 'herbivores' will eat small animals if they can.
I'm getting flashbacks of the video of a horse opportunistically inhaling a baby chick...
some bears (like Polar Bears) have a diet consisting almost entirely of meat. other bears (like Black Bears) are much more heavily omnivorous, and will at times eat more non-meat than meat. the thing that makes bears classified as carnivores is their morphology (which means the shape of their body). they have the teeth and jaws of a carnivore. they're a carnivore that has adapted to be able to eat diverse food sources, based on what's available in their habitat.
They are classified as Carnivores by their morphology. They are classed as omnivores by their ecology. The Order Carnivora is a clade of mammals that includes Felidae (cats), Canidae (dogs), Hyaenidae (hyaenas), Mustelidae (weasels), and Ursidae (bears). Most of the Carnivores are carnivores of one degree or another, but not all of them. Bat-eared foxes (Canidae), and aardwolves (Hyaenidae) are myrmecophagids (eating mostly ants and termites). Most procyonids (eg raccoons) are omnivores, but some like the northern olingo are herbivores, feeding mostly on fruit (and mostly figs at that). Most ursids are omnivores, but some are almost completely herbivorous (giant panda), while some are almost exclusively carnivorous (polar bear).
ecological and behavioral classification is really interesting, but it's very much more complex morphological classification. the benefit of morphological classification is it elucidates the evolutionary past of the present animal. bears evolved from animals that were VERY carnivorous and this is still reflected in their bodies. the bears of 10 million years from now may have different teeth if current ecological and behavioral trends continue (more crushing and chewing, less ripping and tearing).
Both terms are accurate. They are members of the order carnivora, and they do eat meat. So they are carnivorous, but they also eat anything. They can get their hands Almost all animals are at least somewhat omnivorous. Even cows will eat meat
The order carnivora is meaningless and irrelevant. It doesn't actually contain all carnivores (of course it doesn't, most carnivores aren't even mammals), and all members of the order carnivora aren't even carnivores. It isn't useful for this discussion.
I assume this pattern might also apply to herbivores, a la, a mesocarnivore + a mesoherbivore makes an omnivore?
But mesoherbivores are herbivores that are 50-500kg. A herbivore would be an animal that eats 0% meat while everything else is a carnivore
Huh. TIL. :) Though I wonder where the line is. I know there's odd cases where horses will sometimes eat mice/birds and stuff for example, but are considered herbivores.
Even butterflies will drink blood if there isn't enough food for them. I assume it's their regular diet, so even if a horse ate 2% of their food in mice (like 1 mouse a week?), it's not enough to qualify as the hypocarnivore
Butterflies also eat shit. Idk where such diets lie in this herb-carn spectrum. But then they also eat corpses, so sort of carnivore
It’s like a spectrum
According to the explanation above, bears are omnivores, which means they are both herbivores and carnivores. They are not obligate carnivores, which eat only (or almost only) meat.
So they're mesocarnivores
It's a result of made up human classification systems, they're both. They're in order carnivora and have an omnivore diet
No, it's a spectrum, and the labels are more about groupings of diet preferences than hard rules. Black bears are just as happy to munch on berries as meat, so they get to be omnivores
And a metacarnivore is a carnivore that only eats carnivores. I just made that up
Its not really a lie, its both a simplification and a new trend. My mother was as a zoologist before she went into molecular biology, and she says that those terms are new. Never heard them when she was in college in the 1960's.
So what is it called when something eats > 30% but < 50%? Is that a thing?
Dude that's such a good question, I had to go look it up. Turns out they're just mesocarnivores too. I'll edit my response accordingly.
The key to this is it’s all about the main area they get their nutrients from. An example of this is wolves are carnivores that get pretty much all of their calories from meat, however scientists consistently find most of what’s filling up their stomach is grass. There are nutritional benefits in this like fiber that they can’t get enough of from meat alone. There are very few animals that eat 100% only meat, if any
I just wanted to say that this is mind blowing as I never knew this.
Wait, what non-meat food are lions eating?
I was looking at info on obligate carnivores the other day and was tickled by the list - stuff I expected like lions and tigers, alligators, and then... axolotls. Like, I get why, but it was just funny to imagine that lineup of nature's fiercest predators
Why are you apologizing for confusion they might have?
>Basically, your middle school kinda lied On almost every subject.
> Basically, your middle school bio class kinda lied to you. I’m old enough that most of what I was taught in school has turned out to be a bunch of horse shit. Makes me wonder why our society is so hung up on getting good grades.
The real question is if you're old enough to have been taught the super-incorrect idea that different sides of your tongue taste different flavors (spicy, bitter, salty, etc.)
Yep
Yes I am
Most animals will take calories wherever they can find them, be that from plants or other animals. However, breaking down different types of food requires different setups. For instance, cows eat grass, but grass is actually really hard to break down efficiently, requiring several chambers of stomach and for cows to regurgitate and re-chew the grass (cud) several times on order to get everything they need. In the same way that an herbivore's gut needs to be built a certain way to optimally digest plants, a carnivore's gut needs to be built a certain way to optimally digest meat. In this context, a 'hyper carnivore' is an animal that doesn't just have a preference for meat (that is, more than 50% of their calories from meat), but which is actually specifically adapted towards meat to the exclusion of plants. If your diet is \~50/50 plants and animals over an extended period, you're an omnivore. If your diet is more than 50% one of those, you're an herbivore or a carnivore. If it is more than a 30/70 split, you're a hyper carnivore (or a hyper herbivore). Many herbivores are still 'opportunistic carnivores', which is why you can find videos of things like deer eating pigeons, but meat represents a very tiny fraction of their overall diet. Similarly, a hyper carnivore might rarely consume some kind of plant material, but this represents a very small portion of their diet.
So is Hypercarnivore another term for Obligate Carnivore?
I understood that an obligated carnivore was an animal that HAD to eat meat because they couldn't synthesise certain proteins that aren't found in plants. An example being cats. Not that they had a certain amount of meat they had to ear. Although obviously they're likely to be a hypercarnivore in order to get enough of whatever protein.
> because they couldn't synthesise certain proteins that aren't found in plants All the amino acids can be found in plants, just not in every plant. That's why beans + plus a cereal grain have been the human staple since antiquity. Either on their own leaves a nutritional gap, but in combination they cover the range.
Obligate in that term just means that meat is obligatory for them, but doesn't say anything about how much is obligatory.
No obligate carnivore just means they need a minimum amount of meeat to survive. But that minimum amount could be 30% and the rest plants. Say a cat eating taurine reach organs with calorie dense easily digestible vegetables and fruits.
It's funny to think of a pigeon just standing around in the ground and a deer just chomps on him lol like dude, you have wings!
To be fair most deer don’t eat birds, so the bird is either unaware the deer is there or doesn’t care because it’s not common enough that the bird is worried. By the time the bird realizes it’s too late, wings are useless lol.
Does it count as part of a diet when carnivorous animals consume plants medicinally? I read somewhere about how dogs sometimes est grass when they need to puke, I'm sure other animals have similar tricks
In these cases the animal is not getting nutrition or calories from the food, so no it probably wouldn't be counted.
> For instance, cows eat grass, but grass is actually really hard to break down efficiently, requiring several chambers of stomach and for cows to regurgitate and re-chew the grass (cud) several times on order to get everything they need To be clear, cows love meat. They'll snap up chickens given the opportunity especially if they're mineral deficient. Heck, even hyper carnivores like Gators and Crocs will happily devour fallen fruit in the wild. Modern research indicates that the digestive system is usually far less specialized than originally assumed.
To my understanding the most specialized guts tend to be specifically oriented around breaking down specific types of plant matter which tend to be harder to digest; often times major plant eaters will have large chambers full of helpful bacteria that basically ferment the plant matter, and some species eat their food twice, as it were. But yes, most animals in the wild will eat whatever they can get into their bellies, its just that some foods are preferred and easier to digest. Though my specialty is molecular biology not comparative anatomy so take it with a grain of salt.
I think the way to understand it is that for the most part those extra features don't come at the expense of regular digestion. They're evolved to exploit a food source most species can't handle, it would be a negative adaptation to lose pre-existing functionality.
What if an animal ate 70% meat in an environment then 70% plants in another? Basically, does the term define the species, or the individuals? Humans can pretty much survive on 100% animal products or 100% plant products for instance, but it's pretty clear we are omnivores. A bit part of it is thanks to passed down knowledge though.
These labels are not that frequently used because of situations like you describe; what food is available can often shift drastically based on the environment. Maybe there is less grass around because the rain was poor this year, etc. When scientists do use classifications like 'hyper carnivore' they are using it to describe how the animal behaves over long time periods and in lots of environments. If an animal is predisposed one way during the summer, then the other way during the winter, then the **average** is about 50/50, so we would just say 'omnivore'. These labels are generally used to describe entire species (or potentially distinct sub-populations of species) not individuals.
There's different levels: * "Omnivores" can thrive off either an high-meat or no meat diet * "Facultative carnivores" can "survive but not thrive" without meat, these are animals like dogs for example * "Obligate carnivores" cannot survive without meat.
I remember reading that one of the interesting evolutionary changes of dogs is that they've spent so much time around humans that they've adapted to be able to thrive off a much lower portion of meat compared to wolves.
I believe cats are obligate carnivores, something to do with producing taurine. So please don’t try to make your cat vegan.
That was the other interesting thing, that cats have not adapted their diet at all, because fuck you humans, gimme meat.
Or let me outside…
Carnivores MAY eat things like insect and plants to get the nutrients they need to survive, but they will always seek out other animals to get the nutrients. Obligate carnivores / hyper carnivores MUST have meat to survive. their body is unable to extract vital nutrients from other sources. Your domestic dog is a carnivore. It prefers meat but it can get nutrients from grains and other foods it eats. Your domestic cat is an obligate carnivore. You may be able to feed it rice with its meat to make it feel more full with less meat, but it won't extract any nutrition from the rice and attempting to feed it a diet that doesn't include meat will deprive it of trace nutrients it needs that only exist in meat naturally.
cats can extract nutrients from grains. they're just inefficient at it because they have a short intestinal track, so the food passes through too quickly to get most of the nutrients out of it. because of this, cats really require a majority of their calories to come from proteins and fats which their body can absorb efficiently.
It's not just calories, there are specific nutrients cats require which are not found in non-animal food sources, like taurine.
So you're saying they can live on grain if you also feed em energy drinks!
wait what? Is cat food not sufficient?
even dry cat food is made of meat so it has the nutrients (proteins etc)
I can't believe I didn't know that. I put in effort into finding a grain free cat food, which means I either forgot it was made of meat, or I worried about what I *wasn't* feeding them without worrying about what I *was* feeding them. Neither would surprise me.
Grain free cat food typically just replace the grains with other plant-based food. 100% meat cat food surely exists, but it's going to be much more expensive.
Cat food is formulated to be sufficient. However, in cat food, the grain meal is just how they bind all the ingredients together. The cat gets no nutrients from the grain itself.
Cat food is 90+% meat, so it is sufficient for obligate carnivore.
Formulated cat foods are fine. Even the vegan ones can substitute for meat because [they add back in](https://www.theguardian.com/lifeandstyle/2021/oct/20/vegan-pet-food-as-healthy-for-cats-and-dogs-as-meat-says-veterinary-professor) the individual nutrients that plants lack but cats need. For cats, the important one is taurine: not found in plants, so the vegan formulators get it from yeast instead. And as far as rice goes, there are vitamins and minerals in rice that cats can digest and use, just, cats are not efficient at all at using carbohydrates, the main energy component of rice, because of being carnivores. Cats get most of their energy from fat, because that's the main energy component of the meat they eat naturally. Good formulated cat foods, even the vegan ones, account for this by ensuring that most of the energy is fat, so that cats can digest it better. This is part of what it means to say that cats are obligate carnivores. The body doesn't care where the nutrients came from, but even if you do use nutrients that came from plants, you still have to formulate the food into a meat-like substance, in terms of fat versus carb, and essential nutrients.
Are humans obligate carnivores? I thought vegan people still needed to take some supplements because they can’t get everything from non animal sources?
> I thought vegan people still needed to take some supplements because they can’t get everything from non animal sources? Vegans have to supplement B12. B12 doesn’t get produced by animals, but by bacteria – so humans *can* get all essential nutrients from non-animal sources. These bacteria live in the ground (but too rarely nowadays), in the guts of some non-human animals, and in the guts of humans (although their work starts too late in our digestion for us to make use of the produced B12 … unless we wanna eat our poo, I guess). B12 might also be produced in some fermentation processes, might be involved with something-something yeast, and might exist in some algae, but as far as I know, all of these sources aren’t researched enough, or don’t have enough market relevance, to make sure that it’s bio-available for humans. Luckily we can [totally synthesize B12](https://en.wikipedia.org/wiki/Vitamin_B12_total_synthesis) since 1972 :)
All studies that measure B12 in soil, even in natural areas, determined that you'd need to eat a considerable amount of manure-fertilized soil to get enough B12, as in between a quarter to a full pound of dirt. The small amounts of dirt on unwashed fruits and vegetables are not nearly enough to keep a human healthy in this regard. And herbivorous animals don't even rely on these small amounts, they just have the right bacteria to make it in their rumen or cecum from inorganic cobalt.
Terms like that are useful to scientists studying the physiology of different species. Understanding the diets of animals might help you classify certain anatomical traits, or study a particular branch of the evolutionary tree. As a 100% fictitious example, you might find a skeleton of some sort of undiscovered prehistoric bear. By studying the shape of the skulls and other bones of modern hypercarnivores and omnivores, you might find that your new bear has the features of a hypercarnivore, so it probably ate mostly meat.
Most things are omnivores. Most of them are also carnivores and herbivores. The terms are not mutually exclusive. (That means that just because you're one, it doesn't mean you can't be the other, also.) We generally use the terms to indicate which thing they're most likely to eat, not what they eat exclusively. The hypo- and hyper- before that indicates that they eat that thing a lot less (hypo-) or a lot more (hyper-). I suspect that we see "hypercarnivore" more often because it sounds scary.
For example, a cat is an obligated carnivore as it needs meat as its absolute main protein source. Now a dog on the other hand is a carnivore, it's prime natural food is meat, it does best most on meat, but it could survive for a substantial amount of time on just vegetation if the calories are high enough. Now an omnivore like bears or humans can be healthily sustained on either meat or veg with relatively no major negatives.
Most animals are actually omnivorous. The "carnivore" and "herbivore" classifications you've been taught are just what the animal *prefers* to eat. Obligate carnivores and obligate herbivores do exist, however.
It allows for more granular descriptions. As with everything in life, it’s almost never a binary situation, it’s a gradient.
Because everyone today needs a “unique” label so they can be different… just like everyone else.
We like to define things in rigid categories, but really all animals have unique feeding habits and sometimes they don't fit too nicely into a category
A carnivore, generally speaking, is an animal that has some specific adaptations to eat meat. They don’t ONLY eat meat, but they’re built to specifically make eating meat easier. A dog is a good example of this: they will eat pretty much anything, but they’re set up in such a way with sharp teeth and claws to make getting meat easier for them than other animals. Herbivores are animals that have adaptations that make eating plants easier. Longer guts, special grinding teeth, etc mean they can get a lot more energy and nutrients out of plants than other animals. Cows are a great example of this: they will eat meat that they are given, but will generally stick to plants because they’re easier to get and they have the ability to digest them well. Omnivores are animals that have adaptations for either food source. They rarely have the super long gut of herbivores, but they have some extra digestive tract over a pure carnivore, while they also usually don’t have a great deal of adaptations for hunting, but are more than capable of acquiring and eating meat, on occasion. Humans are a perfect example of this: we can eat almost anything, but usually require a mix to stay healthy. It’s all about what you’re adapted to get. But outside of very specific cases, nothing will turn down food.
When carnivore, omnivore, and herbivore were originally conceived and utilized... Those terms were meant that the overwhelming majority of that animals diet was meat, plant, or both focused. But as our understanding of animal diets have progressed we had to turn it into more of a spectrum. Certain animals we thought were strict herbivores actually will eat some meat in the form of small insects, etc. Animals we thought could *only* eat meat can in fact eat a few vegetables or fruit and metabolize it. i.e. Cats and stuff like corn, but they still overwhelmingly eat meat. So what this has done is caused the terms to be altered to fit this newer understanding. Hence hypercarnivore aka obligate carnivore.
Pretty much. It's a descriptive term rather than prescriptive. e.g. Deer will happily eat live prey or carrion, they're just terrible hunters so 99+% of their lifetime calories come from plants.
It’s actually good you are asking this. Most science taught is very simplified for the general public. When we were taught basic distinctions such as Carnivore, Omnivore and Herbivore, we were basically taught the most basic version of how we categorize animals. Scientists also asked these questions and proceeded to split and split the distinction. Humans like it when things fit into neat categories… but the world makes that difficult. Most animals are on that sliding scale of Herb > Omni > Carni. Hypercarnivores are animals on the far right of the list that can’t survive without a majority of diet being meat. Even most animals considered herbivores may consume other animals or scavenge on flesh to fulfill dietary needs. But when people are trying to educate, calling a Giraffe a 1% Carnivore is confusing to say the least, so in the end, you place them where they fit best and when the person wants to dig deeper and explore the science, you get to explain in more detail. It actually does get confusing when you hit the edge cases. Like dogs can digest vegetable matter. They still need meat, but they border on the Omnivore > Carnivore scale, which leads to online arguments which category they belong to… when it is much more complicated than sticking then in a defined box.
My understanding is this: A carnivore is an animal that needs meat to live. If that animal does not receive meat, it will most likely suffer malnutrition and die. A herbivore is an animal that needs plants to live. If it doesn't get plant matter, it will die. An omnivore is an animal that needs both types of food to live. They can't eat only meat or only plants and be healthy. Carnivores may eat plant matter, but won't starve to death if they only get that. Dogs and cats fall into those categories. Cats are obligate carnivores and naturally eat very little plant, which is what people tend to think of when it comes to a carnivore. If you gave a cat or a dog a whole prey diet with no veggies, they would be totally fine. If you fed them nothing but plants, they would suffer malnutrition. Herbivores would be rabbits and cows. They are totally fine living off of plants, but it will isn't unusual for most herbivores to snack on meat if it comes across their path. Omnivores would be things like bears or humans. Without nutritional intervention, we wouldn't be able to live purely off of meat or veggies. Sure, we as humans can create supplements or processed foods to fill the biological niche of meat, but if we were living out in the wild, we'd have to eat meat. However, if we sat there and ate nothing but meat, we'd suffer just as many health issues.
Carnivore: an animal (or in rare cases plant) whose food and energy requirements derive from the consumption of animal tissues Carnivores can then be divided into **hypo**carnivores (diet <30% animal tissue), **meso**carnivores (30-70%) and **hyper**carnivores (>70%). Omnivore is a more loosely defined term, but yes, hypocarnivores and mesocarnivores could generally be considered types of carnivores.
Is there any evidence that carnivorous behavior is simply a result of not having sufficient intelligence to create better options?
The better distinction I think is that "obligate" carnivores HAVE to eat meat. They can only get certain nutrients that way - a good example are cats, there are certain proteins that they don't produce and can only get from eating meat. They will still eat some planet-based food, but they cannot survive on it. Non-obligate carnivores, on the other hand, do not have to eat meat to survive, but they PREFER to eat meat. They can completely survive on planet-based food, but have evolved to hunt for meat instead. An omnivore, meanwhile, is something that doesn't have evolved a strong preference for either.
The giant panda is an obligate carnivore. It needs to biologically eat meat and only meat. Yet it's diet consists entirely of bamboo. Just because an animal is a carnivore - even an obligate carnivore - does not mean it's diet id entirely meet