What do you think is the main evolutionary driver behind human intelligence?

Question

Adaptability has made us very successful as a species. Language and tool making has given us continuity of knowledge and technology. But what part of our evolutionary journey do you think played a key role in developing intelligence in the first place?

(Just my thoughts: Is empathy a survival trait that triggered intelligence? The need to put oneself in another's position to predict what he might do necessitates reason and logic for accuracy. The ability to hold two or more opposing ideas in one's head also necessitates conflict resolution and reinforcement learning. Empathy is also associated with social groups and cooperation.)

Answer 1

It is argued that protein is what caused our intelligence to boost and our brain encephalization to increase.  Once we began eating meat in large quantities we could then develop a more complex brain.

"But size of brains alone does not explain intelligence" brain encephalization has nothing to do with brain size and is everything to do with intelligance.

Answer 2

I think evolution of intelligence was sped up the most quickly by warfare.   That was also a main cause for a much greater degree of social behavior that extended beyond the local groups.  The ones that could field the most males to attack competitors would become dominant.  Relationships with much larger groups meant there was potentially much more to learn and thus intelligence became more important.

Answer 3

Most mammals have higher cognitive abilities than the other animals out there, and are generally better at things like pattern recognition, memory, social interaction, etc. Humans just happen to be generally way more gifted than the other mammals in this respect, to the point where we manage to take things like pattern recognition into full blown abstract symbolism. This could be a simple case of specialization. We can swing with the monkeys, and swim with the fish, but we can't swing like the monkeys, or swim as well as the fish. Similarly, the fish and monkeys have their brains, but they can't think like a human. The fossil record, as in/complete as it is, shows a slow, steady progression of cognitive functionality in human ancestors over time. At a certain point, a little bit of intelligence goes a long way over the other animals; so much, in fact, that humans essentially filled the nich.

A lot of things could have caused this, but big brains wouldn't have gotten bigger had they not been somewhat successful in the first place. The need for 3D vision for swinging through trees probably contributed a lot to our early complexity, and whatever group of early primate-ape-humans thought it might be a good idea to eat the tasty meat that the big predators left on kills (or in the bones of those kills) seem to have taken it from there. Bigger mammals, like those animals would have been, would need an edge if they were to get to kills before the other scavengers. Reading the signs of an impending kill, even from a distance (who was the first one of these creatures to notice the carrion birds in the sky as a marker for a kill?), and then knowing the terrain in the mind, would have done just that. I think that's one good way the brain got a kickstart in an evolutionary sense, and then there are a lot of examples you could pull that suggest high intelligence was outright rewarded (both in cultural and evolutionary senses) at different times in human history.

Answer 4

Bipedalism

Answer 5

food, water and s*x... the more complicated it becomes to get this stuff, the more complicated we become.  Everything else is just guff around the edges.

:)

Not much too it really.

Answer 6

Necessity and the instinct to reproduce the species  in an ever changing environment.

You answered your own question but life is an amazing, thought provoking conquest.  Great conversation fodder.

Peace.

Answer 7

You can't give any one trait special credit.  It is all built on a sort of trial basis and many have come about as by products. These by products have lead to other by products. One thing leads to another, communication> art> beauty> nobility> religion and so on. Here this site says a little about my train of thought.

http://cogweb.ucla.edu/Debate/Gould.html

Thanks for the good question.

Answer 8

I think it is curiosity or put another way, the desire to know why, played an important part in increasing intelligence. Empathy is something the psychopath or sociopath doesn't have, but they can be among the most intelligent of humans & can emulate empathy. Humans are unique in that from an early age they will repeat expierments until they determine why something works that way.  We know many animals have a better memory than does the human, but I know of no data indicating other animals will try to understand something just for the fun of understanding how or why something happens.

EDIT:

You invited further comment, so I'd like to point out that language processing... both speach & understanding led to more rapid evolution by passing information to others.  However this would not have been effective without the inate curiosity so characteristic to humans. Questions obviously led to the formation of religion & closer bonds as ideas were discussed/debated.

more: 5/24

My hypothesis suggests some bipedal ancestor scavenged a bone from a predator kill, & after eating the meager amount of meat on it, cracked the bone open with a rock to find it contained marrow that the predator could not reach. Therefore they found a method of obtaining high quality protien that allowed for accellerated brain growth.  Now, was the use of that rock on a bone calculated, or was our ancestor just curious?

Answer 9

You answered your own question. The social evolution of intelligence is my favorite theory.

Thought experiment. See how many social interactions you go through in a day with just the amount of people that would be the number populating a small band. And, how you keep all this in mind and memory.

Answer 10

Greed, is the driving force!