Every few months or so, I go through a period of wondering why I am doing what I am doing (as a scientist, that is). It usually happens when I am talking to, or listening to a talk by, another scientist who is studying the mechanism underlying a specific feature of biology. For example, the exact mutations underlying a given disease, the specific cause of a newly emerging disease, or the cascade of interacting hormones that influences a plant’s response to the environment. In other words, when I hear other researchers who are trying to answer questions that have clear-cut answers.
Evolutionary biology is a very stimulating, but often unsatisfying field of study. There are no answers, per se, because we are working to explain phenomena or patterns that are almost certainly the result of multiple interacting factors (and not always in the same way!) We are seeking to describe how selection in the past led to the evolution of the phenotypes we see in the present and ultimately to predict how populations will evolve in response to particular selective forces in the future. Therefore, most of the action either happened well before we were born or will happen well after we are dead, and we are unlikely to find out whether we are “right.”
So why bother? Well, every researcher will have a different answer to this question. But for me, there are (at least) three very exciting reasons. First, because evolution is happening all around us, all the time – we just need to know how to look. Second, because of the new inroads being laid that allow us to understand how our and other genomes evolved millions of years earlier. And third, because experimental evolution allows us to explicitly test how evolution works and what its limits might be. Over the next few posts, I will highlight some of my favorite new work from each of these research avenues and (hopefully) explain why being an evolutionary biologist is not nearly as futile of a task as it might first appear.
Okay, so what does any of this have to do with my decision to change degrees while I was at UVA? Well I thought I wanted to study human psychology; in particular, the role that biology plays in shaping our behavior (oh if my former self could have known that microbes play a role in this, she’d have been too excited to sleep!). I sat through some really great courses, and found the whole field incredibly fascinating. By my third year I had hypotheses… lots of them. I wanted answers. Unfortunately, every paper I read used statistics to attempt to account for confounding factors – like socioeconomic status or how much support a child received from their parents – and I found this very unsatisfying indeed. I wanted to test hypotheses directly. I needed control. Of course, I agree that it is unethical to randomly assign one twin to be raised in one way and another in a different way (or to teach a sick child to be terrified of rabbits), but how else can we satisfy our curiosity? And that is why I dropped out of psychology and became an evolutionary biologist.
Some of my favorite psychology studies:
Two classic studies exploring human cruelty:
1) Stanley Milgrim’s experiment where subjects give electric shocks to others despite their screams.
For a really interesting take on this, with some new insight, I highly recommend the Radiolab podcast: http://www.radiolab.org/2012/jan/09/
2) The Stanford prison experiment.
3) Why was psychology so much cooler before the advent of ethics committees? (Thanks to Jason Mansel for sharing this!)
4) The broken window effect: exploring when crime begets crime (and this one has great control treatments!)
Keizer, K., Lindenberg, S., & Steg, L. (2008). The Spreading of Disorder Science, 322 (5908), 1681-1685 DOI: 10.1126/science.1161405
And good coverage of the study: http://www.economist.com/node/12630201?story_id=12630201