CogBlog

One factor worthy of consideration is the different life spans of fruit flies/insects versus humans. Fruit flies are born, reach reproductive age, lay eggs, and die all within only a few weeks. Humans, on the other hand, average a lifetime expectancy of seventy to eighty years. Consequently, there are varying degrees of risk associated with an ability to learn for each of these organisms. Fruit flies have adapted to rely on instinct because that is the mechanism by which they can most efficiently reproduce and propagate their genes. Humans, however, have an extensive lifespan and live in complex social groups. Humans require more than just instinct to become contributing and successful group members. The risks imposed by learning ability are negligible in comparison to the necessity of humans to be able learn and adapt to their changing environments over a lifespan. A longer life also provides greater opportunity for pursuing goals outside of reproduction. Humans explore a world of friendships, careers, and culture. All these elements demand an enhanced ability to learn, even if there are some risks.

The last two students discussed a majority of the information given from the article so I feel that repeating this would be unnecessary. I'd like to mention some things I found interesting while reading the article.

It was interesting to see the difficulties that arose for some generations who were taught to learn compared to those who performed by instinct. Although it is obvious that humans have amassed a huge potential in brain capacity, it's interesting to see why humans were able to sustain this brain size as well. Maybe it's a wrong question to discover, but I found the discovery that learning capabilities and its relation to life expectancy thought provoking. The article mentions flies who were selected for long life were 40% worse at learning and those who learned faster had 15% shorter lives. I thought it was interesting to relate this to the idea that as humans become smarter, brain size increases, and humans become better at learning, the article suggests life expectancy should be shortened. However, it seems that shortened life expectancy in humans can be countered with technological advances in medicine. Could it be that this is some sort of vicious cycle, that as we are getting better at learning from the collection of more knowledge that we have to balance it with medicine and other discoveries gained from that intelligence?

I found this article to be fascinating, for I, like many others, had previously assumed that everything insects did was instinctual. In addition, I had never before considered that learning is not always worth the costs--I assumed that furthering one's intelligence, regardless of the species, could be nothing but beneficial.

Developing a bigger brain in order to learn more requires that a greater percentage of energy be contributed to the cognitive process. For small creatures, such as fruit flies, this may not be in the biological budget. Fruit flies need to use their energy to gather food and to escape from predators--for there are a great meany predators preying on all types of insects. For humans, the continual development of a larger brain has been beneficial due to the establishment of civilization, but in primitive times a larger brain could have been detrimental. In the days of our ancestors when birth could come hand-in-hand with death, a larger head would have been risky. In addition, more energy was required for hunting and gathering; these are two things that humans no longer need use energy on due to the existence of grocery stores.

It seems that in a relatively stable environment, it would be much more advantageous to rely on instinct rather than taking the time and energy to learn about the environment. However, the article suggests that in environments which change quickly, like that of the bees who learn to extract nectar from many different flowers, learning may be worth the cost.

Clearly, for our ancestors, the benefits of learning and bigger brains were worth the heavy cost. The article mentions that the disproportionate size of an infant's head endangers the mother's life when she gives birth. Similarly, since the brain is so big it requires an exorbitant amount of calories to function properly. This required our ancestors to hunt more (and thus put themselves in more danger) in order to sustain their larger brains. The article also mentions that the larger brain could result in more diseases. Obviously, mental illness is more of a concern when you have a larger brain -- since the brain is bigger and doing so much work, there are more opportunities for something to go wrong. Despite its safety risk and greater effort to maintain, the larger brain prevailed. Perhaps because humans with larger brains could plan and organize how to do these tasks (giving birth, hunting, caring for diseased individuals, etc.) more efficiently and safely than their smaller-brained counterparts, the larger brain survived, despite the negative effects of their more developed brain.