The “scientific” argument used by vegginists is that since we are not made like carnivores, we are then herbivores. Meat eaters are encouraged to look to the science of our anatomy, to learn how our bodies work “naturally”. We are told that if we do, we’ll find we are an herbivorous species.
So I looked.What I found was an oversimplification of information that resulted in jumbled “facts” and false conclusions. I found language manipulations, twisted logic and outright lies. When looked at closely, much of the “science” behind the plant-based movement is propaganda: manipulated, inconclusive or untrue.
This is disturbing, because people’s lives depend on this information.
“If it looks like a duck…” is not good science. Whales are mammals and they look like fish. The largest animal on the planet is a carnivore and it has no teeth. There is a huge variety of digestive systems per eating habit; a duck is an omnivore, as is a bear, and they look nothing alike, inside or out.
Science can get complicated. Dumbing down anatomy, physiology and biochemistry to superficial comparisons only leads to confusion. We aren’t cows, elephants, lions or dogs; we are primates.
I feel the proper question to ask would be “What do the Western scientific authorities have to say about primates and human digestion? What do they say regarding the “science” propagated by plant-based advocates?
Science says our most closely related primate relatives are omnivore
According to Western scientific authorities, among the primates living today, we are most closely related to the chimpanzee. Out of the two chimps in existence, the bonobo (Pan paniscus) is our true living cousin.
The bonobo live in an isolated area in the Congo, a land ravaged by war shortly after the animal’s existence as a separate species was discovered, so there was no real chance for observation and study. But because academic dogma says that small/no canines means the subject eats no meat, the bonobo’s diet has been assumed to be herbivorous. However, observations in the wild and fecal samples, have disproved this assumption. The bonobo has been observed to regularly hunt small mammals like monkeys, squirrels and duiker (small forest antelopes); both as individuals, and as a pack.
Our closest primate cousin, the bonobo chimpanzee, hunts.
Also according to science, our closest ancestral hominid relations, the australopithecines and early homo, have been found to have “a generalist, more baboon-like, dietary adaptation”. A “generalist” diet is an omnivore diet. Baboons are omnivorous.
So the primates we can make a scientifically valid comparison with humans, our ancient ancestors of millennia ago and our contemporary cousin the chimpanzee, both have omnivorous diets eating plants, fruit and meat, on a regular basis.
Actually, science says that “there is broad consensus among paleoanthropologists that meat-eating played a key role in the evolution of Homo“. They also say that “vertebrate predation is a synapomorphy of these sister taxa“. This means that environment and availability is what most likely gave rise to plant eating, as carnivory seems to be a natural characteristic in the primate family.
Per western scientific authorities.
Science says chewing or jaw/tooth structure may not define diet
Another scientific-sounding story used to uphold the idea of evolutionary adaptation to plant food is our jaw movement. Plant-based proponents claim we are herbivorous because of the way we chew: humans chew vertically (chopping up/down, like dogs) as well as laterally (sideways grinding, like cows). Plant-based proponents state that because carnivores have limited to no lateral chewing action, humans are made to eat plants.
The logic goes something like this:
“Carnivores chop and swallow. Herbivores chew. Humans chew. Therefore, humans are herbivore.”
This is not only superficial, but it’s illogical. If it looks like a duck and walks like a duck, it could still be a goose. What is interesting is that even when considered seriously, this argument doesn’t hold water.
Comparative studies between our ape relatives have found that the musculature of the face and jaw, as well as the dentition strength, is much less in the primates who tend to eat softer foods.
For example, the gorilla has stronger dentition and musculature than the bonobo. This means the bonobo may not have the strength in muscle and dentition to eat saplings, branches and pith as the gorilla do, but it has more than enough muscle and dentition for what it normally eats: foliage, fruit, bugs and small mammals.
Being primates, our facial muscles and dentition are similar to the apes, meaning ours work for what we eat and how we eat it. However, because our jaws and dentition are weaker than that of the bonobo, we need softer foods than even they would eat.
Science says the human digestive system is different from carnivores… and herbivores
Further research into the digestive process showed that many carnivores, like the cat, don’t need to chew their food. They just need to make it small enough to swallow. Their digestion happens all in the stomach. They have short, simple guts that processes their food quickly. On average, they make about .5 to 1.5 liters (less than a gallon) of saliva a day.
Cows, on the other hand, chew abundantly. They are ruminant, which means they have a complex digestive system, usually compartmentalized, and most of them eat their food more than once. The first few chew breaks down tough plant fibers and mixes it with saliva to make it more welcoming to microbes. They then “chew their cud” by regurgitating (spitting up or vomiting) this pre-digested stuff so as to chew it again. They can repeat this process a couple of times before they finally swallow and feed from the resulting mass. For this process cows need to create about 100 quarts of saliva daily. That’s 25 gallons of spit a day.
Since cats and cows are the examples vegginists most often use in their propaganda, that’s where I started. However, there is more digestive variety among animals than that.
For example, non-ruminant herbivores, like the rabbit, make cecotropes: little balls of predigested food they poo and eat. Other non-ruminant herbivores have large cecums that ferment plant matter and allows the animal to ingest the result internally. This is why the horse doesn’t chew their cud or eat their poo, they feed from their cecum privately.
Birds have organs mammals don’t, like gizzards, crops, and proventriculi. But it’s interesting to note that while they don’t have a “carnivore’s” digestive system or canines, they can be carnivorous. Ducks, geese, loons, storks, hawks, owls, eagles; even chickens and crows, hunt and eat meat.
When you “look at the science”, the human digestive system is different from all other animals. We are not as simple as carnivores nor are we as complex as herbivores, or birds. We don’t swallow chunks of meat like lions, nor do we chew our cud all day like cows, because our digestive systems just don’t work that way.
When cooking is not involved, human digestion begins in the mouth. We chew our food into a bolus, a combination of food and saliva, mashed into a soft, small, oval pellet that’s starting to digest even before we swallow. For this process we create about 1-1.5 liters of saliva daily. Objectively speaking, that’s less than a gallon, and much closer to a cat than a cow.
Plant-based advocates are right in saying that our digestive system is different from carnivores. The lie is when they insist that we are like herbivores. Not only are we “set up” differently, but we definitely don’t digest our food like they do.
Science tells us that humans process our food differently from other animals. Science says human beings process our food like human beings.
Other objective observations of our digestive differences
Further evolutionary fabrication includes the “gut length theory”. The logic goes like this: longer intestines means an herbivorous diet and a shorter one means a carnivorous diet. Since human intestines are longer than that of a dog, we are herbivores.
Science says that while this gut length ratio may be common, it’s not a norm. The panda is an herbivore and it has “carnivore length” intestines. The seal is a carnivore and it has “herbivore length” intestines. There are even fish and lizards that adapt their guts to their diet. An objective observation of the human digestive system as compared to other animals will show that, yes, human intestines are “too long” for a carnivore, but they are also way “too short” for an herbivore.
And these are not the only differences.
Have you ever wondered why the cow, the horse or the gorilla have such huge tummies?
It’s because they are herbivore!
That big belly houses multiple stomachs and extra organs, all necessary for heavy ingestion and processing of plant material, which is “…tough, and…difficult to digest“. Plant matter is also incomplete and offers less nutrition for the amount of work the body needs to put into digesting it. It’s why humans living on plants only, need supplementation, fortified and enriched foods. It’s why herbivores spend most of their waking time eating. And it’s why the herbivore’s digestive system and process is so ridiculously different from ours. The roughage herbivores eat has to either remain in the body a long time or be re-ingested and processed more than once, to give the gut bacteria the opportunity to break it down and allow the animal to feed. And when you really look at it, you find that cows may eat grass, but they live off their internal bacteria!
Comparing human digestive anatomy with that of a cow, shows how immensely different we are.
True carnivores, like cats, have mostly shorter, simpler digestive systems, because meat is easy for the body to digest. They have one large stomach that leads to short intestines that make quick energy from their meals. They don’t have extra organs like rumens. But interestingly enough, because obligate carnivores get all their nutrition from meat, they have no cecums, either.
Herbivores and omnivores do.
I found the cecum interesting as it is a necessary organ for digesting plant matter.
When we compare the relative size of the herbivore cecum, like those found in cows, elephants and horses, theirs are much larger than the cecum of omnivores, because their whole diet consists of cellulose and water. Omnivore cecums, like those found in the chimp and the dog are much smaller, because they get nutrition from sources other than plants. But it’s interesting to note that even among omnivores, the human cecum is incredibly small, meaning, according to science, we don’t depend on it as heavily as herbivores or even other omnivore do.
Comparing the human digestive anatomy to that of other primates shows our digestive system is still very different! Ours is smaller in relation to the rest of our bodies, even compared to chimps! Our stomachs are smaller, with short guts made mostly of small intestine, where other animals have mostly colon. Where chimps have a large, functional cecum, a human’s cecum is a 3.5 inch cul-de-sac corner of gut that was considered useless until just recently.
Looking into the science showed me that while human beings are similar to many animals, we are not the same. Humans seem to be somewhat unique in our digestion. And it makes sense when you consider that we are the only human species on the planet. Any comparison with another animal will always fall short.
Vegginists will often say the human stomach is not designed to eat meat due to a lack of stomach acidity and often misquote a natural stomach pH of around 4-5. Again, science does not support this opinion. According to western medical science, someone with a stomach pH over 3.5 would be diagnosed as diseased and treated medically.
All together I gathered that human digestive acidity varies, not only by the location you are studying (stomach vs colon) but also by age, diet and individual constitution. An infant is born with low stomach acidity because they won’t be chewing meat for a while. And as our bodies go aging, our stomach produces less acid. Beyond the limits of age or disease, a healthy, human adult has a stomach pH between 1.5 -3.5.
Scientific authorities say that human stomach acidity is a lot more similar to the acidity of “carrion feeders”; scavengers, like vultures (1.2), as opposed to that of herbivores, like cows (7).
This research was particularly interesting as it also demonstrated inconsistencies between stomach pH and dietary habits. For example: human stomachs are more acidic than that of cats (3.6), which is very interesting because cats are obligate carnivores. Also, there are other omnivores who have a higher pH than we do, like rats (4.4), dogs (4.5) and baboons (3.7); as well as herbivores with very low pH like rabbits (1.7) and beavers (1.9).
This inconsistency between stomach acidity and feeding discredits this vegginist propaganda. Both the rabbit (1.7) and the cow (7) are herbivore and yet their stomach acidity are extreme opposites. Could it be that this difference is because the rabbit eats it’s excrement and the cow doesn’t? This makes sense if our millennial ancestors were scavengers. It would correlate with those scientific findings that suggest our “stomach acidity evolved as a barrier to pathogen colonization“.
The amount of information I’ve gathered was too much for one post, so I will be sharing further findings as I go. But so far, what I’ve learned from “looking at the science” is that while we share superficial similarities with a variety of animals, our differences are fundamental to how we function. Ignoring these truths doesn’t make them go away. Ignoring them is already costing people their lives…
In “looking at the science” I sought to validate at least one or two vegginist claims because some of these stories sounded convincing, and let’s face it: everyone wants a magic solution. I made objective comparisons between the anatomy and digestive system of humans, to that of both herbivorous and carnivorous animals, and most especially to that of other primates. My results did not support the scientific sounding stories of how homo sapiens evolved herbivorous.
Instead, I was reminded as to how intimately interconnected we humans truly are with All Our Relations and the Planet. I learned how deeply we need each other and how easily humanity screws it up when we believe we know better and look to impose our own ways. We’ve seen this in the westerner’s never-ending colonization practices, in their land grabs, and in their wars for oil and dominance.
And the colonization continues even today, with our foods.
(c)A.Nanu Pagan, March 2018, revised, Jan 2020
More references for your own research
NOTE: This writing was split to make it a more comfortable read. You will find references both, as links in the writing, as well as below for both parts I and II. Enjoy!
https://www.sciencedirect.com/science/article/abs/pii/S0047248417301227- Chimpanzee vertebrate consumption: Savanna and forest chimpanzees compared
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5052503/ 1-1.5 litres daily
dairy products, beans, nuts and seeds