Says who? As a moral argument, that sounds like it's all right to do anything that you have the power to do.
Non sequitor. There was no moral argument anywhere in my post. You're the one making moralistic judgements, not me.
This is the naturalistic fallacy again. Evolution doesn't prescribe anything.
"You keep using that word. I do not think it means what you think it means." In fact, it doesn't. You're using the term wrong, and creating remarkably stupid straw men.
Again, since you seem to have missed it:
1) Humans evolved the ability to process a wide range of foodstuffs, including animal products. This is a demonstrated biological fact.
2) Humans need external sources of Vitamin B12 to survive; since we are not able to synthesize it. This is a demonstrated biological fact.
3) The only naturally occuring source of Vitamin B12 is from animals who are able to absorb it from symbiotic hindgut bacteria. This is a demonstrated biological fact.
4) Therefore, humans are obligate omnivores, and by nature require animal products to survive. QED.
5) It is only through the use of modern technology that humans have been able to construct a diet that completely excludes any and all animal products. Again, QED.
Evolution doesn't have any intention. The fact that my ancestors had success as hunter gatherers doesn't mean I have to do the same. (By that argument, we shouldn't farm or live in cities because "we evolved to be hunter gatherers".)
Non sequitor.
Also, B12 is synthesized by bacteria. It's usually found in meat, eggs and dairy. I'm a vegetarian, not a vegan. It's not essential to eat meat to get B12.
But it is essential to get animal products, barring the use of modern technology to produce B12.
And although B12 is found in eggs, the bioavailability is very low, due to co-exising factors which block absorption. Eggs are not a reliable source of B12. Only meat and dairy are.
Even so, a typical multivitamin supplement has something like 18mcg of B12 giving 300% of the RDA for that particular nutrient. Vegans can get these supplements that are made from the microbial fermentation of brown rice.
In other words, through the use of modern technology.
Also, the soymilk called Silk is made without any animal products, and 1 cup of it contains 50% of the RDA for B12. (I guess it's made from fermented soy or something like that.)
Nope. Soy does not contain B12. Any B12 is derived from bacterial or yeast sources.
Note: it's not actually possible to get B12 directly from bacteria naturally; as naturally-available bacteria do not contain B12. Some, such as spirulina, contain substances which are very similar, but do not perform the same function in the human body. The only bacteria which produce usable B12 are animal symbiotes.
Seriously, does evolution shackle our behavior?
When there is insufficient technology to overcome evolutionary limitations, then yes, clearly it does. How many people were able to fly prior to the advent of modern technology? Anyone manage to do it just by flapping their arms and wishing real, real hard?
Likewise, until the technology existed to understand what Vitamin B12 was, it's necessity, and how to produce it independent of any animal source; eating animal products was an absolute necessity. It is no longer necessary because our technology has developed to the point where we can use it to overcome evolutionary limitations. But even that is limited to people who have access to that technology.
Are you similarly opposed to wearing synthetic fibers as clothing? Does it bother you that so many of our useful products are made out of synthetic materials? What difference does it make if my B12 comes from a fermentation vat or "natural vegetable sources in nature"?
Which is precisely my point. The decision to not use animal products is a religious/philosophical one; and is only possible through the use of modern technology. (And, as previously noted, there are no "natural vegetable sources" of B12.)
I'm a vegetarian myself, and few things irritate me more than sanctimonious, self-righteous vegans who attempt to elevate their dietary preferences to the level of moral imperatives; and deny the fact that they're only able to pursue their chosen diet due to the actions of people and institutions they commonly deride.