Article outlining mainly herbivorous nature of humans/vitamin B12

blatantrereg

Here's an article outlining the basic physiognomy of herbivores, omnivores and carnivores, and comparing human anatomy with those. It suggests humans are a lot more similar to herbivorous animals than anything else:

http://www.vegsource.com/news/2009/11/the-comparative-anatomy-of-eating.html

Chimps are the only other primate that eats meat. That behaviour has only been observed in fairly recent years and might even be a recent development in their behaviour. This study suggests it is a lot to do with social behaviour and not much to do with nutrition:

http://www-bcf.usc.edu/~stanford/chimphunt.html

It seemed to me that the hole in the "we are slightly adapted herbivores" theory is that common knowledge indicates that vitamin B12 is unlikely to be sufficient in a vegan diet without supplementation. However I've been reading a bit about vitamin B12 and it is pretty much produced by micro-organisms and eating dirt or eating things that ate dirt. So my [limited] knowledge on the subject would seem to indicate that this isn't a hole in the theory at all. We evolved to eat food that wasn't always as nicely cleaned as would be the norm today.

Any thoughts?