Evolution in the changing oceans

I teach evolution. Yes, in Georgia. Here at the University of Georgia, we have 300-400 students a year taking undergraduate evolutionary biology, and some of the Honors students at UGA take an extra discussion section for credit. This year I picked up the Honors section as well as the lecture class, and decided to have some fun with it. Instead of “read a paper, summarize a paper, discuss the paper”, one of our goals as educators should be to stimulate discussion and bring some sense of community to the classroom. One way to do that is to establish a collaborative project for the students, and I’m a fan of what motivated people can do when unleashed on a wiki.

A back story to my contribution here was a workshop held on Santa Catalina Island in 2010. Led by Gretchen Hoffmann, Brian Helmuth, Amy Moran, and David Hutchins, along with Phil Taylor and David Garrison from NSF, a group of scientists gathered for some really intriguing discussions about the role of evolutionary processes in altering some of the predicted trajectories for species and communities given the range of environmental and climate change scenarios that we face today. The meeting was fantastic, some good ideas were taken away (and certainly acted on by some of the participants), but I hadn’t had a chance to do anything with these ideas myself.

Back to teaching. College students, for the most part, get climate change. And even though most or all of the students in Honors evolution at UGA have not had an introductory ecology class (bummer!) or much formal training in environmental biology, we are surrounded by the evidence for climate change. Not just in the news and on the web: Georgia is in the midst of either one of its greatest droughts in history  – or is this the new normal?

So, I gave the students a particular theme for the semester: we would pick up the discussion about evolution and climate change, and to keep me content we would continue to focus on marine biology! It turns out there are many good reasons for that marine focus beyond my background [e.g. Sunday’s work showing a tigher latitudinal fit for marine ectotherms than terrestrial organisms, given their thermal tolerances]. The other challenge I gave them: we would build a website together.

This latter challenge required a few tweaks to the standard read-and-discuss format. First of all, I asked the students to become experts in an area of their choice. The first week, we discussed environmental and societal facets or influences on climate change, listed those and assigned one to each student, and each week – in addition to the one or two papers the class read and discussed – they were asked to find another resource relating to their “beat” that they could consider and add to the discussion, so that gradually as the semester progressed we had a class with an expert on extreme weather, ocean acidification, gene flow, and so on. The other thing we had to do was gradually learn how to use the wiki I’d set up.

I have a Mac OS X server that I use for data management on some of my NSF projects, and the OS X Server software includes some really nice tools for collaboration, including a wiki server. I’ve had experience managing wikis using MediaWiki (what runs Wikipedia), and 3-4 other wiki packages that run on python or other data resources. I even use VoodooPad for my personal ‘brain dump’ (or, if you are into Harry Potter, my pensieve). All of these have their merits and deficiencies, but what usually stymies colleagues is ANY level of having to learn some form of mark-up language, as is necessary for Wikipedia editing. So the Mac OS X flavor was good in this respect – very easy to use. It also allows, as with any wiki, for multiple editors at once; to track and compare changes over time; and to identify who has made which edits.

This last bit was important. Since this was a class, I wanted to be able to watch what the students were doing to the website. I have to emphasize that I attempted to keep my hands off the website, other than the syllabus and main ‘splash’ page, and a few minor edits or comments to encourage the students. I set it up so that anybody can see the page, anybody can comment (but I moderate the comments, and sometimes I forget to check them for a few days…), but only I and my class can edit it. The other reason it was important to be able to see what the students were doing, not only so I could assess progress and even assign credit through the semester for their contributions (generally just a flat 0 or 1 – did they contribute in a given week or not?), was so that they understood that ANYTHING they did, anywhere on the page (intellectual, editing, reorganization, and so on), could be a contribution.

Honors students are funny animals, as many of you know. The initial instinct, as the website took shape, was for each of them to stake out their own page on the wiki and add brief summaries from the papers they had read. Essentially saying, “Dr. Wares, this is my space, and here is a standard short summary of a paper as I’ve been taught to do in other classes.”  But of course, a good resource to the public doesn’t involve an endless list of summaries; it is a synthesis. I kept encouraging them, that they could edit and link to and combine material from each others’ pages and resources, that I could see it all and give them credit. I told them that they needed to view this page not as their homework for me to see, but as a resource that others might be able to come across, read, and if interested click a link and learn more.

It took a while, but here at the end of the semester we have a pretty damned good resource for anybody who is interested in climate change and how organisms may respond to climate change. In particular, our focus was of course on the potential for marine organisms to adapt, and so the students learned very well by the end of the semester the importance of large effective population size, of what we could learn by looking at reaction norms across temperatures and across developmental stages, of what heritability really means, of how biodiversity works together in an endless beautiful (if now disrupted) cycle. Part of this exploration involved them coming to a critical realization that evolution isn’t entirely the answer: some organisms won’t be able to adapt in time. Many organisms will probably respond with changes in their geographic range more rapidly than they could respond with changes in allele frequencies. And some won’t respond at all.

All of which makes it that much more interesting to think, in a dispassionate way, about what change we will actually see in the biosphere in the coming decades. Compared to what was, this change is bad. We all have reasons to protect and fight for a cleaner, sustainable future. However, as scientists we also can see the coming decades as a time to understand better how this whole thing works (or worked). This is what a good education is supposed to lead to: the more you learn, the more curious you become. And I’m not making any great claims about my teaching, but this class led to some really good discussion and discovery. Most of these kids are pre-health in some way or another, but a better understanding of evolutionary biology (think: viruses and antibiotic-resistant bacteria) and environmental biology (how do we guard against a toxic environment for our own good, if not the good of other species?) is good to see in any student heading out into this great big world.

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