Wednesday, December 8, 2010

What's the next "big thing" in evolution?

This is the type of question people ask all the time. Indeed, our Monday seminar speaker asked my opinion on this question in our one-on-one meeting. I'd be curious what some of you folks think. I gave a talk on this, specifically with respect to speciation (my research focus), at the Linnean Society of London last September.

Immature subfields thrive on dichotomies, and then they mature with realization that there are always exceptions to the "rules" (if "rules" even existed). For my evolution colleagues, think about these classic or even recent dichotomies- classical or balanced school? Does natural selection or genetic drift shape DNA sequence variation? Did species evolve via sympatric speciation or allopatric speciation? Is divergence driven by regulatory changes or amino acid coding changes? Case studies always come up to show "at least one" case of the putatively rarer type.

We then grow a little bit to ask about "relative frequencies." The question is sometimes then reworded slightly to "which is more important", but even that's a can of worms- is "rare" equivalent to "unimportant"? Surely not. Does it really make us rethink things if one happens 80% of the time vs. 20%? Or even 95% vs 5%? (I might concede 99.99% vs. 0.01%.)

Further maturation sometimes goes to, "What are the conditions that favor X over Y?" or "In what species/ types of genes/ networks/ whatever do we see X being more abundant than Y, and what does that tell us about their differences or trajectory?" thus changing the discussion from pattern-based to process-based. However, although these questions are more mature, they rarely grace the top "magazines" (Science and Nature) in which we often strive to publish. Instead, the magazines favor the primitive dichotomies, especially when the underdog theory can be demonstrated. A few years ago, an editor from Science magazine asked me what she should seek out. My answer was, "I don't know, but please DON'T publish another marginally stronger proposed case of sympatric speciation." (They actually did, the next year.)

Obviously, I'm overgeneralizing. There have been many very interesting observations in evolutionary biology that didn't fall into the dichotomization trap or follow the path I described. Elegant models have been developed and later strongly supported or conclusively falsified. And Nature and Science do sometimes publish "mature" results. But what IS the next big thing? Personally, I am skeptical it would be "an extended synthesis", as some have argued. I also doubt it's obvious in other recent "buzz-topics", like "evolutionary medicine" (which is useful but I don't see it as a paradigm change).

So, what is it? Thoughts?


  1. Next big thing: independent evolution of life forms that use alternative elements to either carbon, phosphorous, or nitrogen.

  2. From another Rich:

    I'm going to go out and a limb and say a "next big thing" is predicting the consequences of local extinction: specifically, if a species becomes locally extinct, will it be able to re-establish? Or will other species adapt to occupy the abandoned niche, expanding their own realized niches while blocking the re-establishment of a competitor. I don't view this as a simple L-V competition model, since the competition coefficients could change as a consequence of local extinction of a competitor. Perhaps some conservation biologists are thinking along these lines already.

  3. My two cents: Origin of life, epigenetics, evolvability, canalization, horizontal transfer, medical (e.g., cancer) applications. Other than that, mere filling gaps of the modern synthesis, the tree of life based on whole genomes of all living taxa, and looking for spectacular fossils.
    Pawel Michalak