Why do humans need to eat plants and fruits to be healthy, but large carnivores (Tigers, Lions, etc.) don’t?
In: Biology
So for orcas (killer whales) for example, aquariums used to order and feed them filleted pieces of fish. And they wouldn’t understand why they’d keep getting infections and need antibiotics.
Later they started giving them whole fish. There’s a lot more minerals in the other parts of the fish, particularly the skeleton and perhaps also the brain IIRC.
That didn’t eliminate infections but it did reduce them.
Large predators are really well evolved. As long as they can access their natural food sources, they usually get the nutrition they need. That and sufficient genetic diversity are their keys to not getting seriously sick.
You don’t
There are no essentials carbohydrates in the human diet.
You only need protein and fats to survive.
Red meat contains pretty much all the vitamins and minerals you would ever needs. Liver even more so.
There are many 100% carnivores health nuts with perfect blood samples.
Lots of things to consider here:
1. We have an intellectualized idea of “health” that is riddled with _values_, not survival. From an evolutionary perspective “health” means you live long enough and well enough to have babies that can grow up to have babies. From this vantage point you (human) don’t need to eat a well balanced diet and can get all your needed nutrients from meat. The large cat isn’t thinking to themselves “how do I make sure I feel good and and can live to see my grandkids” and then altering their behaviors.
2. Without cooking, vegetable nutrition is largely unavailable to a cat – just not what they are built for. Even for humans, energy efficiency of (within the human, not total environmental system) is really bad for raw vegetables – we work really hard to get a little nutrition. This is why all the energy spent on a hunt is actually less NET energy than is often required for “gathering” in the hunter-gatherer society. Agriculture changed the game, allowing us to produce massive amounts of vegetables, then cook them and get a major boost in the “ROI” of eating vegetables. Cats don’t do any of that, although cooking vegetables does make some nutrition available to their system.
Different guts are better equipped to extract different nutrition for different biological needs. Humans have gastrointestinal tracts and diets that benefit growth and development of a comparritively large and energy-costly brain, while (for example) a lion, has a gastrointestinal tracts perfectly evolved to extract the nutrients it needs from meat to fuel it’s comparritively large muscle growth.
Just because we don’t see them eating their veggies, doesn’t mean they are not. Large carnivores eat their entire prey, meaning that the stomach and what’s in it get eaten. Anything an antelope has eaten that remains in it’s stomach at the time of it’s death, the lion will also be eating and gaining nutrients from.
Some animals most notably carnivores can convert the food they eat into desired vitamins and other essential chemicals, but converting the food takes extra effort, it is more efficient to get those substances from your food, humans as omnivores don’t need to use up that extra energy so no longer are able to change some substances.
Humans are not carnivores, we’re omnivores—we evolved to eat a diet that has a lot of variety to it. People can eat all vegetarian and live, and they can also eat all meat and live, but there can be deficits in such diets that are less likely than in cases of a very varied diet. We evolved from apes that ate a vegetarian diet. Meat then became a key component of our diet and our digestive tract evolved to be able to process the eating of meats and plants.
Latest Answers