Fire - Human Evolution

[Novidez]

Yesterday, I had a brief 'discussion' about fire. One person said this to me:

"Humans (species in the genus homo) are the only animals that cook their food and Wrangham argues Homo erectus emerged about two million years ago as a result of this unique trait. Cooking had profound evolutionary effect because it increased food efficiency which allowed human ancestors to spend less time foraging, chewing, and digesting. H. erectus developed a smaller, more efficient digestive tract which freed up energy to enable larger brain growth. Wrangham also argues that cooking and control of fire generally affected species development by providing warmth and helping to fend off predators which helped human ancestors adapt to a ground-based lifestyle. Wrangham points out that humans are highly evolved for eating cooked food and cannot maintain reproductive fitness with raw food."
Source: https://en.wikipedia.org/wiki/Catching_ ... e_Us_Human

How do you argue that? Is this completely a lie?
(I must be honest that this was my (enforced) reality too. And, probably, for everyone)

[Aytundra]

What about this perspective on brain size development?

The aquatic ape hypothesis (AAH), often also referred to as aquatic ape theory (AAT),
...
Encephalization: The human encephalization quotient, an expression of the size and complexity of the brain of a species, compared to its physical size and other factors, is considered the highest in the animal kingdom, followed by whales, in particular dolphins, other great apes, elephants, certain species of squid and some intelligent birds.[38]
...
It has been argued that aquatic mammals more often develop large brains, and that particularly grassland mammals conversely stagnate in brain development.[40] Morgan[33] and other authors[41][42][43] have suggested that the encephalization of the human brain was a response to increased consumption of seafood.
Source: https://en.wikipedia.org/wiki/Aquatic_ape_hypothesis

How do you argue that perspective?

[Kasper]

there was a study lately debunking this and saying the crucial part was humans to be able to cut food in smaller pieces and not cooking per se

[Novidez]

How do you argue that perspective?

I can't argue it. But when I was talking about this subject, I didn't know this .
The thing is when I was discussing about this, I am always wondering. But they were really convicted that this was the reality, that thousands of years people know about this. They just gulp this 'reality' and that's the holy truth.

Thank god, Wai Forum exists!

there was a study lately debunking this and saying the crucial part was humans to be able to cut food in smaller pieces and not cooking per se

Do you remember the source where you read that?

[Kasper]

http://www.nature.com/nature/journal/v5 ... 16990.html

"The origins of the genus Homo are murky, but by H. erectus, bigger brains and bodies had evolved that, along with larger foraging ranges, would have increased the daily energetic requirements of hominins1, 2. Yet H. erectus differs from earlier hominins in having relatively smaller teeth, reduced chewing muscles, weaker maximum bite force capabilities, and a relatively smaller gut3, 4, 5. This paradoxical combination of increased energy demands along with decreased masticatory and digestive capacities is hypothesized to have been made possible by adding meat to the diet6, 7, 8, by mechanically processing food using stone tools7, 9, 10, or by cooking11, 12. Cooking, however, was apparently uncommon until 500,000 years ago13, 14, and the effects of carnivory and Palaeolithic processing techniques on mastication are unknown. Here we report experiments that tested how Lower Palaeolithic processing technologies affect chewing force production and efficacy in humans consuming meat and underground storage organs (USOs). We find that if meat comprised one-third of the diet, the number of chewing cycles per year would have declined by nearly 2 million (a 13% reduction) and total masticatory force required would have declined by 15%. Furthermore, by simply slicing meat and pounding USOs, hominins would have improved their ability to chew meat into smaller particles by 41%, reduced the number of chews per year by another 5%, and decreased masticatory force requirements by an additional 12%. Although cooking has important benefits, it appears that selection for smaller masticatory features in Homo would have been initially made possible by the combination of using stone tools and eating meat."

[Novidez]

Thank you Kasper, really interesting!

it appears that selection for smaller masticatory features in Homo would have been initially made possible by the combination of using stone tools and eating meat."

They say "initially" which seems to suggest that cooked foods allowed that to continue and (maybe) progress even more... But, of course, this is a mere speculation of mine.

[Novidez]

I saw this video that promotes a Low-Carb diet: https://www.youtube.com/watch?v=VSRDfkt-wJY

There's this study that says our brain increased since we start eating meat.
https://courses.edx.org/c4x/WellesleyX/ ... issue_.pdf

According to Waysays,

Only when we started combining fruits with animal foods, between 3 and 2 million years ago, the size of our brains rapidly increased.
What made the capacity of our brain increase?
The combination of sugars and cholesterol. Simply because sugars are the main source of energy for the brain, and cholesterol is most essential to the brain for construction purposes.

Also, on that video, min 9:30, he explains we had big bellies. There's a thing he says that intrigues because it's true: how the fruits were completely different in the past comparing to nowadays. This is, they had much more fiber.
http://www.sciencealert.com/here-s-what ... cated-them

--\\--

What is this Stable Isotope Analysis about?
16:30, I don't like the way he says "he goes from the big game to a more marine animal kind of profile". I want to understand what he means by "big game". It clearly seems better than the "marine foods game".
However, we have this "It has been argued that aquatic mammals more often develop large brains, and that particularly grassland mammals conversely stagnate in brain development.[40] Morgan[33] and other authors[41][42][43] have suggested that the encephalization of the human brain was a response to increased consumption of seafood. "

[RRM]

... we had big bellies. ... the fruits were completely different in the past comparing to nowadays. This is, they had much more fiber.

Yes, more fiber, and thus bigger bellies.
Luckily, we have juicers and sieves now.
Raw seafood is also very easy to digest.
Juices and raw animal food; the perfect brainfood.

[Novidez]

Juices and raw animal food; the perfect brainfood.

It's interesting because, regarding evolution, it seems that if we somehow manage to bother our guts less (like on Wai xD), we will evolve even more.
However, there's this claim that our gut influences a lot our brains. Actually, they call it the second brain. If somehow we could make us not pooping at all, the gut would be taking some vacations, so to speak. Would that be really benefic or worse to our brains?
Also, even the act of chew, it is said that is important to transmit some signals to our bodies and make it function better. Maybe it is just a conspiracy... is it?

[RRM]

If somehow we could make us not pooping at all, the gut would be taking some vacations, so to speak.

Of course not, as the gut has to deal with all the nutrients.

[Novidez]

Juices and raw animal food; the perfect brainfood.

Isn't cooked animal food even easier for digestion?

[RRM]

Sure, but the carcinogens are not good for your brain, and the beta-carbolines impair brain chemistry.