I found Ed Yong’s TED Talk, Suicidal Wasps, Zombie Roaches and other Parasite Tales, the most interesting of the videos we watched. I enjoyed it because we don’t talked much about parasites in our biology classes, but the way they have evolved to profit at the expense of another organism is so complex, but seems very simple and elegant from a distance.
It’s fascinating that parasites can play such a large role in the behavior of organisms, such as causing brine shrimp to swarm together and make them more visible to flamingos. I’ve always assumed that animals are fairly conscious of their actions, or at least that their impulse to behave in a certain way is their own, not a form of biological mind control by a parasite. It was also crazy to me that the emerald cockroach wasp injects venom into very specific regions of the cockroach’s brain, altering its behavior by eliminating its desire to run away from danger.
As Yong stated in the talk, this does bring up the question of whether humans are totally in control of their own actions. While I’m not convinced that our actions are controlled by parasites, it’s worth considering the idea that we don’t have as much freedom in our actions as we’d like to believe. Everything that we do—all of our experiences—shape who we are and ultimately our perspective. I think that our past can strongly influence our reactions to the present. Our behavior is based partly on how we perceive the situation, and interpretations vary from individual to individual. In a way, we are not totally in control of our behaviors because our automatic appraisal stems from events that have already transpired and cannot be changed. That isn’t to say we are mindless, head-banging zombies like the caterpillar in the TED Talk, we do have a lot of freedom of thought, but I do think there is a small component of our behavior that is programmed by our past.