Very interesting debate.....I am studying a degree in wildlife conservation so we study a lot about adaptive physiology.I would push that we are omnivorous by nature. The anatomy of herbivores and carnivores are very, very specialised, whilst ours is incredibly generalist. We could not in a wild situation considering environmental factors arising once we left the trees, survive as either carnivore or herbivore. We do not have the gut structure to process large volumes of meat fast enough for it not to putrefy, whilst converesly, cellulose is INREDIBLY hard to digest, and requires specialist structures to get the most from it. The teeth of herbivores are complex structures designed to perform a level of grinding ours just can't do, and many such as ruminants have complex microfloras doing the digestion for them.... they also have to hock it back up and re chew their dinner! Those who don't, like horses have to eat and eat and eat and eat, and you see most of their dinner undigested in their poo. Very inefficient animals. Rabbits have a cyclical system whereby they munch, poo, and eat their poo to obtain as much nutrients as poss.Thus we are opportunistic browser types.... we get what we can, where we can and when we can, and our main physiological adaptation is our brain and innate innovativeness, and the social biology which increases our capacity to work together to achieve common goals.Adaptation does not necesarily reflect evolution however. In evolutionary biology there is this concept called "evolutionary continuity" which basically means traits do not go "ping" into existence... they take a long while to form, and a species may spend a very long time seemingly maladapted to its lifestyle.Take the Giant Panda... the worlds worst excuse for an animal bless its heart. Its just rubbish at life! It eats a soley herbivorous diet of a completely un nutritious food source.... bamboo...... yet it still has a carnivorous digestive system and teeth! it must eat constantly, and because the food is so rubbish, it cannot afford to hibernate, thus expending extra energy through the winter...... Its nutritional budget is allllll screwed up......But somehow, it plods onWhat got man so far is our innate adaptivity. Another concept..... Adaptive radiation.....a form of speciation. Were we not so able to mix between each other, we would have began to evolve from distict races into species in perhaps a few more thousands of years due to accumulated adaptations... you can already see it in the climatic variations in hair colour and skin tone.How could we ever have colonized the northern temperate zones without eating meat? Seasonal variations dictated diet. Once the growing season ended and the cold began, to remain herbivorous would have resulted in death. Individuals better adapted for processing meat would have been selected for through the process of mortality. Chances are, in northern climes our diet would have been predominantly herbivorous in summer, and carnivorous in winter.Having said all of this, the modern day meat industry is a terrible place. Welfare issues are abhorrent in their scale, and the meat itself is full of hormones and other chemicals.......... their is a current trend for lean meat, which comes from exploitation of mutations.....Its called Double Muscling......google it... its freaky... Look for the picture of a greyhound with the mutation... You would assume it photo shopped but no its real. And then there are the terrible environmental effects exerted by the livestock industry and fish farming.I enjoy meat personally. But I like it to be well sourced. I prefer more than anything game meat that has lived a wild free life, and had a fast painless sudden ending. Having processed it yourself and experienced the whole hands in guts, smelly experience you appreciate the meal at the end of it FAR more. Its exactly the same when you collect fungi and nuts and berries etc. Any food got by your own hand you have a spiritual connection with. A lot of tribal cultures feel that eating certain animals imparts their spirit and power upon them, which is a beautiful way to view a meal, as opposed to stuffing a burger down your chops when you're drunk lol!Death is a part of nature that no animal can escape, and that 99% of the time will come far before its natural lifespan. Thus I am not against the killing of animals, but I am against needless cruelty and a lack of respect for them, and the idea of treating them as a 'product'... a 'commodity'... where the minimum welfare standards are far below what would be acceptable for say a dog!However, the death nature provides for most animals is cruel and prolonged and awful....so to be shot, unless the animal is unfortunately wounded and escapes, is probably a far better fate than either the slaughter house or natures fate.In the uk for example we have no large predators left because of our intense persecution of them all.... no bears, no wolves, no lynx.... all gone
so Deer for example are now left predator less.... they increase exponentially and damage woodlands. The only limiting factor is disease and parasite burdens when numbers get too high. An awful way to die I'm sure you'll agree. Normally older animals would be taken down by wolves but no.... Not in Britain.... an old deer will grind its teeth down to the point where it can no longer chew it enough. The bulk of the food goes to the rumen, and because its too big for the microflora to process, it simply ferments...... you end up with a skinny deer with a massive belly and it starves to death......Old age for them is not the picnic we enjoy. To reach old age is an awful fate in the wild.Thus we manage deer populations quite intensively... there is a whole science to determining populations, maintaining a correct sex ratio, and age ratio, how many need to be taken out each year to maintain a stable population etc etc... You have to do a Deer stalking certificate of competency etc etc..... And all these culled animals are sent to the game dealer.. That to me is an example of the most welfare conscious and acceptable part of the meat industry there could possibly be as it is all engineered to maximise health of the nations deer herd, and keep the habitats in which they occur in healthy condition.Ultimately, I believe if you cannot face killing an animal yourself. if you cannot handle the smell of death and guts, and you can't stick your hands in gooey guts, then you have no right to eat meat. For me, the veggie stuff is my daily staple, with meat items a luxury I cherish, and when people can buy a 2.50 chicken from morrisons with ammonia burns on its legs straight from a massive overstocked barn of HELL,, come all clean and pre packaged..... and then turn their noses up when i bring home a rabbit just because its cute and adorable........ oooohh that makes me mad.....People do not see meat as animals. They see it as just some munch. Nom nom nom, no thought and that makes me MAD.Sorry bout the irrelevant off topic ranting, I couldnt help myself :P