Humans are animals and animals have different gastric ph and acidity depending on the species. Some obligate carnivores have much stronger acids than others (hyena is stronger than grizzly, for example).
You’re claiming that gastric pH levels do not coincide with the type of diet an animal eats? Cite your evidence.
Ability to store vitamin A coincides with the type of diet an animal eats. Correct?
Name all the biological adaptations you know of that distinguish humans from other apes, by which to conclude that humans are "true omnivores".
Whereas some herbivores also have specific organ and flora mechanisms we don't have to destroy plant toxins and/or break down tougher plant cells. Our stomachs are capable of handling both to more limited extents, just like most omnivores. It's worth pointing out that humans are **** at breaking down cellulose like obligate herbivores
So your argument here can be stated as a simple
modus tollens deduction: If (P) humans are herbivores, then (Q) humans would harbor cellulolytic gut bacteria by which to digest a significant portion of consumed cellulose. Not Q. Therefore not P.
That argument is unsound; the facts lead to just the opposite conclusion. It has long been known that humans commonly harbor cellulolytic gut bacteria by which most cellulose is digested. This is a 1984 paper:
Ample evidence for breakdown of cellulose in man has been acquired by non-isotopic techniques and has been reviewed elsewhere.9 Balance studies in humans where intake of dietary cellulose and faecal excretion have been measured and the source of cellulose was commonly eaten foods, such as fruit and vegetables and refined cereals, cellulose digestibility was of the order of 70-80%.5
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1432575/pdf/gut00393-0005.pdf
This from 1988:
ABSTRACT The fibrolytic microbiota of the human large intestine was examined to determine the numbers and types of cellulolytic and hemicellulolytic bacteria present. Fecal samples from each of five individuals contained bacteria capable of degrading the hydrated cellulose in spinach and in wheat straw pretreated with alkaline hydrogen peroxide (AHP-WS), whereas degradation of the relatively crystalline cellulose in Whatman no. 1 filter paper (PMC) was detected for only one of the five samples. The mean concentration of cellulolytic bacteria, estimated with AHP-WS as a substrate, was 1.2 X 10(8)/ml of feces. Pure cultures of bacteria isolated on AHP-WS were able to degrade PMC, indicating that interactions with other microbes were primarily responsible for previous low success rates in detecting fecal cellulolytic bacteria with PMC as a substrate. The cellulolytic bacteria included Ruminococcus spp., Clostridium sp., and two unidentified strains. The mean concentration of hemicellulolytic bacteria, estimated with larchwood xylan as a substrate, was 1.8 X 10(10)/ml of feces. The hemicellulose-degrading bacteria included Butyrivibrio sp., Clostridium sp., Bacteroides sp., and two unidentified strains, as well as four of the five cellulolytic strains. This work demonstrates that many humans harbor intestinal cellulolytic bacteria and that a hydrated cellulose source such as AHP-WS is necessary for their consistent detection and isolation.
http://www.researchgate.net/publica...nd_hemicellulolytic_bacteria_from_human_feces
can't handle a lot of common plant based toxins like a lot of obligate herbivores
Cit your evidence.
can't manufacture vitamin b12 in high enough quantity to not need animal supplementation or cultivated through modern bred yeasts
And you're claiming that humans' inability to "manufacture vitamin B12 in high enough quantity" distinguishes humans from herbivorous mammals? I mean, really?
No fungi, plants, nor animals (including humans) are capable of producing vitamin B12. Only bacteria and archaea have the enzymes needed for its synthesis. Some plant foods are a natural source of B12 because of bacterial symbiosis.
https://en.wikipedia.org/wiki/Vitamin_B12
