At The Molecular Ecologist today, I highlight a couple of recent literature reviews that seek to understand how natural populations are structured by the limitations of distance, and by local adaptation:
Taken together, these two papers are a nice compilation of a very large literature. If nothing else, they demonstrate that we’re well past the point of asking whether environmental isolation happens at all—in fact, it looks to be quite common—and we’re ready to start digging into the details of when and why it develops.
To see what broad patterns two different groups of authors were able to extract from their surveys of many population genetic studies, go read the whole thing.◼
The Life Sciences building at the University of Idaho. Photo by jby.
Over at Nothing in Biology Makes Sense! I’m confronting my discovery that the University of Idaho, where I received my Ph.D., has hired an outspoken proponent of young-Earth creationism to teach its introductory microbiology course this semester:
I can, at least in principle, imagine a creationist professor who taught the contents of a microbiology curriculum, complete with the common descent of life on Earth, and never breathed a word of his personal beliefs in the classroom. Could Gordon Wilson—of all people—be that “gold-star” creationist?
I decided the only way to answer that question was to ask Gordon Wilson.
The probable selective impact of Joshua tree’s pollinators is obvious—it easily catches in the sieve of our attention and our desire to work with interesting critters. But I think it’s also fair to ask how much an interaction as specialized as the Joshua tree pollination mutualism actually tells us about the evolution of much more common, much less finely co-adapted relationships.
Do you ever worry that your study system limits what you can, well, study? Go read the whole thing, and tell us in the comments there.◼
Welcome, pollinators! But, um, everyone else can just stay out, okay? Photo by Yeoh Thean Kheng.
Over at Nothing in Biology Makes Sense!, I’ve written about a neat study of the tropical vine Dalechampia scandens, which has to solve an evolutionary puzzle that confronts most flowering plants:
But there’s a downside to making a big, showy display to attract pollinators—you might also attract visitors who have less helpful intentions than gathering up some pollen and moving on to the next flower. Showy flowers might attract animals that steal the rewards offered to pollinators—or they might attract animals that eat the flowers themselves, or the developing seeds created by pollination.
To see how a team of biologists directly measured this evolutionary compromise (spoiler: it involves counting pollen grains with a hand lens) go read the whole thing.◼
At The Molecular Ecologist, guest contributor K.E. Lotterhos discusses an important consideration in designing studies that “scan” the genome for regions experiencing natural selection—to be truly informative, they must “triangulate” using independent data:
Let’s say a number of individuals were collected from heterogeneous environments on the landscape. Some SNPs were significant both in an FST outlier analysis and a [genetic-environement association]. Would we consider these SNPs to have two independent sources of evidence?
NO, because the two tests were performed on the same sets of individuals.
What counts as “independent” in this context? I think that’s still something of an open question—but go read the whole thing and se what you think!◼