Humans-omnivores or herbivores?

[Infinity Blade]

I don't usually talk on general discussion because frankly, I'm not extremely well versed on many topics pertaining to it. But this is a topic which I think I sort of am, so do you think we're naturally omnivores or herbivores?

[creature386]

I believe we are omnivores:

I said:

We have no tangible adaptations towards the consumption of flesh (object if you will), and a plethora in favor of vegetation digestion (again, feel free to refute).

Blaze explained that in the "Homo sapiens- A herbivorous species?". You don't need obvious adaptations (claws, power) when you can help yourself otherwise (by using weapons). Digesting is no problem either. You gave the response in your comment (cooking).

That having been said, chimpanzees are not even all that omnivorous. Less than three percent of a common chimpanzee's diet is composed of meat; the figure is significantly reduced for the bonobo. The overwhelming majority of their diet, of course, is fruit. That goes for four of the six great ape species, excluding humans. All orangutan and chimpanzees prefer fruit over all other foods, and if it is available ubiquitously and continuously, they will gladly subsist as exclusive frugivores. The two remaining species, the gorillas, rely mainly on foliage, but eat fruits as well. All species consume insects on occasion, but I doubt that is the focal point of our discussion. So applying your very own logic, we are undoubtedly frugivores. If you wish to betray your argument, be my guest, but otherwise, my point is proven by means of your own.

I didn't know about that. I knew that chimps mostly eat fruits, but I thought that insects or small apes would make up at least 10% of their diet. At least Wikipedia called it an "omnivorous frugivore" (if you have evidence for the "undoubtable" frguivore, feel free to post it).
Maybe you don't like Wikipedia, so here a science paper:
link.springer.com/article/10.1007/BF02347830
The first sentence already supports what I wrote about the omnivorous chimp. Maybe by far not as omnivorous as humans, but far from a herbivore.
You can read what the paper said. They are undoubtable primarily fruit eaters (that's what I would also recommend to a good human diet BTW), but meat makes up a significant portion of their diet (click "Look inside" and read the introduction). Also, they are far from inept when it comes to digestion of meat (this of course mean uncooked meat):
onlinelibrary.wiley.com/doi/10.1002/ajp.1350180105/abstract
I am very well aware that a partially carnivorous diet is not the rule in most primates though, but chimps are more closely related to us than gorillas or orang utans and bonobos (which are about as closely related to us as chimps) also consume some meat ( www.eva.mpg.de/fileadmin/content_files/staff/barbara_fruth/pdf/Hohmann_Fruth_Prey_MeatEating_Folia2008.pdf ).

I don't know how you can claim it allowed our ancestors to become stronger; primeval hominids will negligible meat consumption were obviously stronger than us, and animals further up the line, such as the australopithecines, were extremely superior physically (but, obviously, ate vegetation in bulk).

I can very well claim this:

A study of human and pre-human diet history shows that for a period of at least 2 million years the human ancestral line had been consuming increasing quantities of meat. During that time, evolutionary selection was in action, adapting our genetic make up and hence our physiological features to a diet high in lean meat. This meat was wild game meat, low in total and saturated fat and relatively rich in polyunsaturated fatty acids (PUFA). The evidence presented in this review looks at various lines of study which indicate the reliance on meat intake as a major energy source by pre-agricultural humans.

link.springer.com/article/10.1007/s003940050005

There is a common myth that eating meat allowed our brains to become larger. This is incorrect, as far as I have uncovered, and believe me, I have researched the claim thoroughly. It appears that accelerated brain growth (evolutionarily speaking) began to take place around the time we developed fire. This also coincides with increased meat consumption, because it is difficult to consume raw for unnatural omnivores, but overall, the benefit of fire is that it allowed food to be digested with great ease, and thus, the energy yield was greater, and so less time had to be allotted to meeting caloric intake requirements. This in turn allowed a larger brain to be more practical, as it could more easily be fueled, but it certainly did not magically procure the genetic arrangements required for such an adaptation, and we had been tending toward larger brains for a long time to begin with anyway, so I can say assuredly that we would have been more or less physically equivalent to our current selves without meat having played a role (maybe even superior, judging from our primate kin!).

Cooking certainly helped to consume more energy, but meat is nevertheless a factor which scientists take into account on this matter:

www.cnr.berkeley.edu/miltonlab/pdfs/meateating.pdf
If there was more than one factor, the single factors may be less significant than if they were alone, but it does not assure you that they were irrelevant.

carnivoraforum.com/topic/10061750/3/#post8638452

[Infinity Blade]

I too believe we're omnivores.

Obviously there's more to the "humans are herbivores" notion than just our physical characteristics, but I'll just weigh in on a couple arguments that pertain to this.

There's the claim that humans don't have sharp teeth, claws, or particularly large mouths. However, since Homo has/had the ability to fashion tools that aid in carcass dismemberment, anatomical structurs that fulfill the same function are quite unnecessary. Even then however, our dentition is not entirely unsuited to consuming meat. Our incisors have shearing crests that allow us to shear off a piece of food, whether it's a piece from a fruit or a piece of meat. And although our canines are reduced in size and not the fearsome fangs of say, a big cat, they still have a clear pointed morphology that allows them to puncture and tear. I think it would be accurate to describe our canines and incisors as 'generalist' in function, which is in line with omnivory.

There's also the claim that we humans can move our jaws in a lateral motion and hence masticate, something carnivores are unable to do. Well, we're not arguing that we're carnivores, we're arguing that we're omnivores. We of course need to be able to chew the plant matter in our diets. Moreover, some people have even brought up the possibility that the ability to move the jaws laterally is not as developed in humans as it is in true obligate herbivores. If true, then that too points to generalist jaw capabilities.

[blaze]

After doing basic research the only ones that can still content that we are herbivores are deluded vegetarians/vegans that only read blogs by other people with their same unsupported bias, how else can myths that fail human digestion 101 become so widespread such as "meat rots in your stomach" and "we suck at digesting meats and fats"? which are actually the opposite of reality.

[creature386]

It is interesting how Marek called my points "the most repeated fallacies on the Internet".

[theropod]

Why is there a herbivore option, but not a carnivore one? We are just as much carnivores as we are herbivores (i.e. we are obviously omnivores). Herbivorous (not omnivorous!) Primates tend to have very obvious adaptions of their masticatory system (take Gorilla, or Paranthropus).
We on the other hand have descended from facultative carnivores, most of us eat meat if they can get it (and unless you are one of those deluded vegetarians blaze mentioned, you’ll acknowledged that that’s within the diet we are adapted for), and our closest living relatives are facultative carnivores as well. There’s really not the slightest doubt that humans are omnivores.

[Infinity Blade]

Why is there a herbivore option, but not a carnivore one?

Because I've never heard of anyone that argues that we are natural obligate carnivores.

[theropod]

There’s no sane person who argues that we are naturally obligate herbivores either. And there are fully carnivorous people (peoples living in polar regions) as well as fully herbivorous ones (vegans).

[Infinity Blade]

Sept 1, 2014 23:16:49 GMT 5 blaze said:

After doing basic research the only ones that can still content that we are herbivores are deluded vegetarians/vegans that only read blogs by other people with their same unsupported bias, how else can myths that fail human digestion 101 become so widespread such as "meat rots in your stomach" and "we suck at digesting meats and fats"? which are actually the opposite of reality.

I've been looking into this subject more. I still hold my original opinion, but could you elaborate more on the "meat rotting in your stomach" part? Also, could you explain the whole thing with vitamin B12 and our stomachs as well (I want a better understanding of it)?

References would be utterly awesome too.

[Venomous Dragon]

What kind of obligate herbivore would be so awful at digesting cellulose?

[blaze]

@macronectes

I think this is a very good summary of what's up with vitamin B12 in plant foods, it includes references: link
Long story short: plants neither store nor produce vitamin B12, in the cases where some have been found to contain it, it is by contamination from bacteria. Some contain analogues (derived from symbiosis with bacteria) but none have been found to be active in humans so they are useless to us.

The meat rotting in your stomach part came from some vegan blogs I was reading at the time, arguing that once meat reaches our digestive tract it sits there for long periods of time (several days or even weeks) and it has to rot before your body can break it down, it will take me a while to track down specific references from the literature but from what I've read, meat and fat is easily digested by the enzymes produced by our bodies(up to 97%), plant matter on the other hand, what our own enzymes can't brake drown (most of it) is left for our gut bacteria to process and our bodies then absorbe their waste, still, as we don't have specialized hervibore guts nor the right gut bacteria, a significant portion of the plant is left undigested (cellulose).

[Infinity Blade]

"There is a one paragraph report often cited in vegan literature for showing that B12 is found in the soil. Robbins et al. (25) (1950, New York) used Euglena gracilis var. bacillari as a microbiological assay for vitamin B12 "or its physiological equivalent." A considerable proportion of bacteria and actinomycetes (molds) in the soil were found to synthesize B12 analogues. B12 analogues were also found in the roots of plants (.0002-.01 µg B12/g of fresh material). Some stems had some B12 analogue, but leaves and fruit generally did not. B12 analogue was also found in pond water and pond mud. There was no indication in the report as to how many different soils were tested, but the impression was that it was all in one local area. It is not known whether these B12 analogues were active for humans.

Is this where that no vitamin B12 analogues have been found to be active in humans is derived from? Or was it from something else?

Edit: just gonna drop this here.

theethicalomnivoreblog.wordpress.com/2016/05/20/humans-are-omnivores-not-herbivores-not-carnivores/

[creature386]

Some people at my school today discussed his humans are obligate herbivores or not. I've heard stuff like "eating meat is as bad as smoking". And this is in fact not made up:
www.sciencedirect.com/science/article/pii/S155041311400062X
Their methodology (NHANES III surveys) has been criticized:
journals.plos.org/plosone/article?id=10.1371/journal.pone.0076632
But what about their other claims (such as testing the deleterious effects of amino acids/proteins on mice and unicellular organisms)?

[creature386]

Just found this:

• Human ancestral diets changed substantially approximately four to five million years ago with major climatic changes creating open grassland environments.
• We developed a larger brain balanced by a smaller, simpler gastrointestinal tract requiring higher-quality foods based around meat protein and fat.
• Anthropological evidence from cranio-dental features and fossil stable isotope analysis indicates a growing reliance on meat consumption during human evolution.
• Study of hunter-gatherer societies in recent times shows an extreme reliance on hunted and fished animal foods for survival.
• Optimal foraging theory shows that wild plant foods in general give an inadequate energy return for survival, whereas the top-ranking food items for energy return are large hunted animals.
• Numerous evolutionary adaptations in humans indicate high reliance on meat consumption, including poor taurine production, lack of ability to chain elongate plant fatty acids and the co-evolution of parasites related to dietary meat.

onlinelibrary.wiley.com/doi/10.1111/j.1747-0080.2007.00194.x/full

[rock]

i have substancial proof humans are not herbivores or carnivores , since the early stone age humans have been hunting and gathering this is first grade knowlage , we have been hunting buffulo and zebras and we have also been eating berries and fruits . we are not herbivores because we lack the digestive fluids to digest raw vegetation [grass , wheat, flowers] we are more on the omnivore side as our digestive system is more simalir to other omnivores [pigs , dogs , bears and chimps].





this image clearly shows that our digestive system is similar to dogs and pigs both of which are omnivores than it is to horses and sheeps both of which are herbivores . in additon it is a comman myth that vegans will live longer than omnivores or meat eaters . this is not true , they only live longer because they eat less fatty foods , unlike omnivores and meat eater who will tend to eat more fatty foods and more fatty meat . people have lived over 100 years by just eating cooked fish and others have survived by just eating insects . vegans tend to eat pure foods that are not saturated while meat eaters and omnivores on the most part tend to eat more fatty foods . also it is a misconspection that we must be herbivores because we can get high cholesterol , this is again not true , cats can get high cholesterol and so can dogs.

if you do not belive me go to these web pages


wagwalking.com/condition/high-cholesterol

canna-pet.com/causes-high-cholesterol-dogs/

wagwalking.com/cat/condition/high-cholesterol


i do not think anyone would say dogs and cats are not carnivores just because they can get high cholestroal .



in additon some people say we do not need meat because we make our own cholesterol , again this is not true , we can only make 90% of our own cholesterol we need another 20% that comes from eating meat or getting pills . so no we do need meat and we cannot produce   cholesterol all by its self without meat or at least pills.




for more on that check this video out


www.youtube.com/watch?v=MWWRbuypIXo




so no we are not herbivores and are not carnivores . hopefully this has cleared up the misconsception that we are herbivores and not omnivores . 



edit: i stand corrected , dogs are carnivores not omnivores just not as picky as cats who are strict carnivores.