About 2.5 million years ago, hominids started out with abrain weighing approximately 400-450 grams (approximately 1 pound), but around 200,000 to 400,000 years ago, our brains became much bigger than those of other primates [source: Kouprina et al.]. Now, we humans walk around with brains tipping the scales at 1350 to 1450 grams (approximately 3 pounds) [source: Kouprina et al.].
More work is needed on the role of ASPM, microcephalin and other genes involved in the growth of our brain, but one reason why scientists are so interested in brain size is that it has been linked with intelligence. Bigger brains might portend bigger IQs. So if the ASPM and microcephalin alleles are in fact causing our brains to evolve, what are the possible destinations? Will we be bigger-brained and smart enough to realize some amazing inventions? Or is mankind on a slippery slope down to Stupidtown?
There are still many facts about our brain that people would not mind to eliminate, such as depression, diseases, and so on. Many researchers suggested that human’s brain has reached a certain level that would not be needed to evolve, however some recent reports say it differently.
ASPM andmicrocephalin. When mutations in these genes occur, brain size is affected. Since ASPM seems to have evolved faster in apes than in creatures such as mice, it's possible that it may have something to do with how our brains evolved.
But wait, where is ASPM going with this?
But no one wants to imagine a future in which we become dumber, right? That means the next step for our brains may not be a natural evolution so much as a genetic engineering to ensure that our brains are the best possible brains they can be. Think of how our society already relies on antidepressants and other drugs to correct brain malfunctions. Eventually, we may be able to engineer defects out of existence.
We are going to become terminators
we'd become a species called Homo cyberneticus, a human species that's slightly assisted by some silicon enhancements. As this species proves successful, we'd use the practice more, to the point where our "brain" was entirely computer-based. This species would be known as Homo hybridus, as it would have a body similar to ours. But Pearson foresees one major flaw with Homo hybridus-- eventually, the organic parts of the individual would wear out and die. This will lead to the rise of Homo machinus; this species will be made entirely out of silicon and will essentially have immortality. The brain will be able to back itself up, and parts will be repaired or replaced.
And sure, there will probably be things we'll lose forever in this transition, some attributes that those computer brains can never have, like creativity. But really, one could argue that with the glut of reality shows that are already on the air, creativity may already have died.