>>82538415A huge proportion of plants are poisonous or indigestible when they're old enough. Our perspective is a little warped because we evolved to tolerate or even prefer it in order to get a wide diet. Carnivores would be similarly confused by our inability to process gristle and spoiled meat, and of course true herbivores would be able to stomach much harder and rougher plants than we can. The "free" foods that are easy for everyone to digest are very young leaves and newborn baby animals, and anything else needs counter-strategies to deal with their defenses.
We have a wide range of enzymes that can take care of a huge range of foods and accept a lot of "close enough" alternative nutrients, we generally resist weak toxins (effective against insects) due to our size, our stomach acid is very strong, and our long-ass digestive tract means our gut flora can adapt to and target foods we can't fully absorb. It's pretty good but never gets into extremely specialized territory since it has no way of handling hard shit like nuts and bones. A lot of animals will surprise you with the weird bullshit they can eat, but you can't ignore that we are also very impressive.
You can see in the fossil record that other hominids were more adapted to eating plants in the forest, able to crack nuts and grind down roots and shit with their teeth. Gorillas are able to do this and it forces them to maintain a large territory they slowly comb through, often subsisting on low-calorie foods like tree bark for long periods of time (similar to bears). This strategy obviously fucking sucks which is why we don't do it, but we can still eat a lot of same foods... if they are softened externally first.
The main area where the human and dog lifestyles are compatible is in social behavior AND long-distance running, so we can return to forage sites and pursue prey over obscenely long distances compared to most other animals. If anything, the difference in our diets means we are competing less for food and can cooperate easier (e.g., dog gets the stomach and liver, I get the muscle meat, dog gets the bones, I get the skins).
