So if it turns out that the alleles in ASPM and microcephalin are causing our brains to evolve, what might the outcome be? We might like to think that there's nothing but bigger and better things ahead of us, but British researchers have claimed that our brain is already operating at maximum capacity. After creating models of how our brain works now, it seems that we've reached our maximum ability to process information, or we're probably within 20 percent of that number [source: Ward]. If our brain did get bigger, other organs would have to grow as well, particularly the heart, which would have to work harder to power a bigger brain.
The researchers also found that we're facing a bit of a vicious circle in terms of increased intelligence. For the brain to take in more information, the connections between brain cells would have to become wider, so as to speed up the rate of the brain's information superhighway. But to support that, we'd need more insulation for those connections, as well as more blood flow to the brain to support the connections. That, in turn, leaves less room for the expanded connections. And if the brain became bigger, the messages would only have farther to go, slowing down our already efficient processing times [source: Ward]. Other research suggests that the metabolic demands necessary for evolution mirror genetic changes that occur in schizophrenia, perhaps indicating that neurological disorders accompany brain evolution [source: BioMed Central].
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.
And if we wanted to improve our intelligence? Some are starting to stay that if we want to do that, we may have to form an alliance with computers. Roboticists at Carnegie Mellon University estimated that computers will surpass our processing capacity by 2030 [source: Lavelle]. After we exhaust genetic engineering mechanism to improve our brains, we may have to supplement our minds with a computer interface. A futurist named Ian Pearson has considered how an evolution with the aid of computer parts might proceed.
First, Pearson suggests, 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.
The thought of Homo machinus may make you uncomfortable, particularly if you've seen a little film called "The Terminator." But you can already sense how our reliance on computers is growing; consider, for example, a job applicant who shows up without basic computer skills. That candidate likely doesn't stand a chance against applicants who could whip up PowerPoint presentations or Excel spreadsheets in their dreams. Similarly, humans that try to opt out of machine-based parts may find themselves unable to compete successfully with the new species.
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.
So yes, the human brain could evolve and change. The question is, will we still be humans after it happens?
More Great Links
- Associated Press. "Study Suggests Human Brain Still Evolving." LiveScience. Sept. 8, 2005. (Aug. 13, 2008)
- Atkins, C.E. "Seed Interview: Bruce Lahn." Seed Magazine. Sept. 11, 2006. (Aug. 13, 2008)
- BioMed Central. "Schizophrenia: Costly By-product of Human Brain Evolution?" ScienceDaily. Aug. 5, 2008. (Aug. 13, 2008)
- Hofman, Michel A. "Limits to Human Brain Evolution." Netherlands Institute for Brain Research. (Aug. 13, 2008)
- Holmes, William. "Expanding the Human Mind: The Future of the Brain." The Futurist. July/August 2007.
- Kouprina, Natalay, Adam Pavlicek, Ganeshwaran H. Mochida, Gregory Solomon, William Gersch, Young-Ho Yoon, Randall Collura, Maryellen Ruvolo, J. Carl Barrett, C. Geoffrey Woods, Christopher H. Walsh, Jerzy Jurka, Vladimir Larionov. "Accelerated Evolution of the ASPM Gene Controlling Brain Size Begins Prior to Human Brain Expansion." PLoS Biology. May 2004. (Aug. 13, 2008)
- Lavelle, Peter. "The Human Brain: Should We Upgrade?" ABC Science. Sept. 19, 2007. (Aug. 13, 2008)
- Myslinksi, Norbert R. "The Future of the Brain." World & I. August 2000.
- Pearson, Ian, Chris Winter and Peter Cochrane. "The Future Evolution of Man." BT Labs. 1995. (Aug. 13, 2008)
- Wade, Nicholas. "Brain May Still Be Evolving, Studies Hint." New York Times. Sept. 9, 2005. (Aug. 13, 2008)
- Ward, Mark. "End of the road for brain evolution." New Scientist. Jan. 25, 1997. (Aug. 13, 2008)