I’m sorry for asking this. But I always wondered how come cows and buffaloes who only eat grass and stuff get so big? Here I am working out 5 days a week with my job and eating a lot of meat and getting normal results. Sorry again, I have no intention of annoying anyone.
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The largest terrestrial animals have always been herbivores, elephants, rhinos, mammoths, giant tree-munching dinosaurs, and so on. I’m not sure why you think that would be different for buffalo.
Being an herbivore means that you have ready access to vast quantities of food that most animals can’t extract nutrition from, but you can. Having access to large amounts of food allows for gigantism in animals, and being a *large* herbivore means that the predators capable of taking you down must either be large and powerful, or run in packs. Being large also means you can support large fat stores which help you to get through leaner times, and also withstand very cold weather.
They eat a lot of calories. Herbivores have enzymes that let them digest “insoluble fiber” aka cellulose, aka plant fiber. They get a lot more nutrition from plants than humans. These enzymes break open the plant cells, giving them access to proteins and fats not available to us. Plus they never stop eating.
Cattle, Elephants, Hippos, Rhinos, Giraffes these are all large land mammals. They all get large the same way. They eat a lot of food.
Your entire day (whole life, really) revolves around eating. Yeah, grass is low in calories, but when you are basically chewing from the moment you wake up to the moment you go to sleep ,You can put down quite a few calories.
Also, there’s only a couple of things that can eat them.
You’re talking about two completely different species (humans & American Bison). While protein is essential for us to build muscle, that isn’t the case for all animals, not that there isn’t protein in vegetation. Some of the largest land animals (dinosaurs) were plant eaters.
Plants are mostly made of cellulose, which is a bunch of sugar molecules linked into a strong chain.
Humans can’t digest cellulose. For us, eating grass is just fiber, zero calories.
For herbivores like buffalo and cows, they have multiple stomachs and special enzymes and bacteria that let them break down cellulose into usable sugars. **For herbivores, eating grass is like eating bread for humans**. It’s a form of carbs for them.
The other factor is large herbivores spend hours and hours a day eating like 50 lbs of grass. If you eat 10 loaves of bread a day you’d be 800 lbs in a few years too.
You aren’t annoying anyone, this isn’t a terrible question.
But, the answer is, why wouldn’t they? You cannot apply the rules of human nutrition to other animals. Let me flip your logic for a second…..
There are jungle cockroaches that can run 150 times their body length in one second, and can lift 20 times their body weight, that eat nothing but rotting wood. OBVIOUSLY, if you go out and eat a straight diet of rotting wood, you won’t et that strong or fast.
Humans are not good at digesting grass. We lack the enzymes, physical structures (like multi-chambered stomachs and grinding teeth), gut microbes, and lifestyle to get the most out of grass and other tough plants, unlocking the nutrition.
We lack the DNA, growth hormones, sex hormones, bone structure, and life cycle (ontogeny: the study of development and life cycle) to turn into giant muscular tanks, in the same way buffalo lack our ability to live to 60-70 years.
Because the lower down the food chain you go, the more calories energy a food contains.
So imagine a simple food chain: Sun > Grass > Buffalo > Bear.
To make 1kg of Buffalo, you need 10kg of grass.
To make 1kg of bear, you need 10kg of Buffalo.
The bear needs the caloric equivalent of 100kg of grass, whereas the buffalo requires only 10kg because it eats the plant directly.
From a calorie/energy point of view, the further up the food chain you go, the more energy is lost at each stage and the harder it becomes to get enough energy, which reduces your potential to grow your population.
This is why there will always be significantly more buffalo than bears.
In terms of efficient calories, it is best to be a plant and take your energy directly from the sun.
But since animals cannot do that, being a herbivore is the next most efficient way, with the minimum possible energy lost.
The answer to your question isn’t why are herbivores so big now? It’s why are they so small? If anything, you think about the era of dinosaurs, you had mega animals who ate megafauna. Huge massive plants and nutrition there that fueled the growth of mega animals. Even the mammals of that time, and since then until relatively recent history, were massive. Giant rats compared to today. Giant sloths. Whatever we had today, there were giant versions before.
Humans, smaller than anyone else, just used the environment better. We burned it all down and killed the megafauna, and thus starved out the mega animals to become the apex there. So grass became the most common plant around, and those animals that thrived on grass stuck around. Those that didn’t, struggled or went extinct. I think it’s the book The Sixth Extinction which goes through this history very interestingly.
In the modern context, your question then comes down to how people massively underestimate veggies now. We’ve been taught that meat is why human brains evolved, why we grow muscles, and so on. Meat companies literally paid schools to put the food pyramid in with meat and dairy at the top and suggest it was the ‘best’ food. The top of the pyramid. And that marketing stuck with us and our assumptions about food.
But you take buffaloes, elephants, gorillas, giraffes, and other large land mammals and you see that the largest and the strongest are herbivores. If you think about what actually fuels a mammal’s brain (glucose) then those question marks start to creep in. Protein wasn’t the answer. Eating a lot more calories (and the particular nutrition) that fueled and allowed more complex thinking was.
Obviously, those animals can process grass. We cannot. We have to farm and grow different plants. But even for humans now, we get 2/3s of our protein on average from vegetables even with such a meat heavy diet today. It’s just interesting that by historical standards, today’s mammals are actually tiny compared to their predecessors.
What we can take from it for the modern world, though, is we shouldn’t assume meat is the best nutrition. Your body needs nutrition. It doesn’t really matter if it comes from an animal or a plant for that sake. You can be healthy eating meat or healthy eating a plant-based diet if either are well planned (both have respective risks and rewards). The biggest separator now, though, why humans are taller than ever, is more because total calories is up. The basic formula of calories in versus calories out explains most of this. Even for humans, we’re taller than past generations because of this. We eat a lot more calories in childhood than we used to, so we grow more. As kids, that means growing taller. As adults, it means growing sideways.
But yeah, ELI5, is that we underestimate veggies. Even in terms of what you say about working out 5x per week. Meat isn’t the crucial factor. Enough nutrients is (esp. in terms of enough nutrients absorbed). Quantity of protein is more important than quality of protein which is more important than timing of protein. You may also be comparing “normal results” to ‘influencers’ who are on steroids. So that’s a whole other ball game. Almost all the popular fitness guys are on the juice. So “normal results” will differ massively there.
If buffalos have got you thinking, I’m gonna blow your mind by telling you about elephants and brontosauri. Or even gorillas–these bulky beasts get super swole by eating plants.
You don’t need meat to get big. Especially when you have a digestive system that is capable of getting nutrition from non-meat sources. Lots of animals have evolved different digestive systems than us. They get more out of the plants that they eat than we do.
(Heck, even humans don’t need meat to get big. We just need protein–and this can come from many non-meat sources.)
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