Life, um, finds a way—except when it doesn’t

This week the LA Review of Books has my review of Unnatural Selection, a nifty new book in which ecological toxicologist Emily Monosson describes how living things evolve their way around the things we humans do to try and contain them.

… the introduction of the insecticide DDT rapidly led to the evolution of resistant mosquitoes, houseflies, and, yes, bedbugs. Decades of farming with the herbicide glyphosate, better known under the brand name Roundup, have led to the evolution of resistance in dozens of weed species. One after another, Monosson ticks off cases, dividing them into chapters corresponding roughly to biological classification. She goes beyond these headline examples to describe lesser-known triumphs of “resistance evolution,” such as viruses evading human immune responses and inadequate vaccination, cancer cells overcoming chemotherapy, and fish that survive water polluted by biochemical toxins.

This hits some of the same themes as that recent review about using evolutionary biology to solve major problems in the coming century, though I might have liked it if Unnatural Selection spent a bit more time discussing the cases when life doesn’t find a way—the myriad reasons we’re in the middle of the sixth mass extinction in the history of the planet. But I highly recommend the book for the folks in your life who may not realize how personal evolutionary biology can be.

Best. Broader impact. Ever.

Like everyone with an Internet connection, earlier this month I heard a fair bit about U.S. 7th Circuit Court Judge Richard Posner’s ruling striking down bans on same-sex marriage in Indiana and Wisconsin. As Mark Joseph Stern put it at Slate, “Posner … sounds like a man who has listened to all the arguments against gay marriage, analyzed them cautiously and thoroughly, and found himself absolutely disgusted by their sophistry and rank bigotry.” Here’s a choice sample from the full opinion:

The challenged laws discriminate against a minority defined by an immutable characteristic, and the only rationale that the states put forth with any conviction—that same-sex couples and their children don’t need marriage because same-sex couples can’t produce children, intended or unintended—is so full of holes that it cannot be taken seriously.

What I hadn’t heard before is that Posner’s opinion also includes a short run-down on research about the biological basis of sexual orientation, and it has more than one familiar citation:

Although it seems paradoxical to suggest that homosexuality could have a genetic origin, given that homosexual sex is non-procreative, homosexuality may, like menopause, by reducing procreation by some members of society free them to provide child-caring assistance to their procreative relatives… There are other genetic theories of such attraction as well. See, e.g., Nathan W. Bailey and Marlene Zuk, “Same-Sex Sexual Behavior and Evolution,” forthcoming in Trends in Ecology and Evolution

That’s actually a reference to a 2009 review, which is online in PDF format—it covers the diversity of same-sex sexual behaviors across the animal kingdom. It hardly mentions Homo sapiens, but it is one of the sources I give to people who want a solid introduction to current scientific thinking about how same-sex attraction could have evolved. If you ask me, one could do a lot worse than having a paper cited in a groundbreaking legal ruling. And it’s a reminder to those of us studying the history of life in general that our work can have unexpected consequences beyond the lab.

To thrive in the twenty-first century, can we learn to steer evolution?

Cliff Swallow in flight

Cliff swallow in flight. (Flickr: Don DeBold)

Many of the biggest challenges humanity faces in the next hundred years are biological: dwindling wild lands and disappearing biodiversity, antibiotic-resistant bacteria, and emerging new viruses, but also feeding nine billion people or more a healthy diet in a climate-changed world. As Theodosius Dobzhansky famously remarked—and as this very website’s name proclaims—nothing in biology makes sense except in the light of evolution. So are there evolutionary answers to all these biological challenges? According to a big new review article just released online ahead of print in the journal Science, the answer is emphatically yes.

The long list of authors, led by Scott P. Carroll and including Ford Denison, whose lab is just down the hall from my office at the University of Minnesota, explicitly connect evolutionary principles to global goals for sustainable development. These include the reduction of both “chronic lifestyle” diseases and infectious diseases, establishment of food and water security, clean energy, and maintenance of healthy ecosystems. Carroll and his coauthors divide the applications of evolution to these problems into cases where evolution is the problem, and those where evolution may offer the solution.

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Why the whale kept its hips

Mystice pelvis (whale).png


A bowhead whale’s highly (but not entirely) reduced pelvis. Image via Wikimedia Commons.

Thanks to a remarkably good fossil record, it’s now well established whales and dolphins evolved from land mammals, their forelimbs adapting into flippers, and their hind-limbs almost entirely disappearing. If you’d asked me yesterday what’s going on with that almost—the last vestiges of the hip bones that whales retain, which have no legs to support or direct contact with the rest of their skeletons—I’d have told you they were evolutionary leftovers, and probably going to disappear in another million years or so. I think a lot of other evolutionary biologists (those who aren’t whale specialists, anyway) would’ve agreed with me. But it turns out we’d have been wrong.

As Carl Zimmer describes, a paper recently published in the journal Evolution points out that whales’ hips do have one remaining function, an important one—they anchor muscles that control the penis. And that function is under ongoing sexual selection.

The more promiscuous a [whale] species was, the bigger its pelvis bones tended to be. The scientists also found that as whales evolved to become more promiscuous, their pelvic bones changed shape. These changes weren’t part of some general change to their skeleton, however. The ribs near the hips didn’t show the same patterns of size and shape change.

I strongly recommend Zimmer’s whole article, and you can also read the original research article in Evolution.

Hawk moths in action, and how biologists study them

As a follow-up to CJ’s post about hummingbird moths—more generally known as hawk moths—let me recommend this episode of Plants are Cool, Too, which features the work of Chicago Botanic Garden conservation scientist Krissa Skogen. At White Sands National Monument, Skogen tracks the nectar rewards that attract hawk moths, and how far the moths carry pollen.

The #IceBucketChallenge, and iced-up budgets for scientific research [Updated]

Ice bucket screenshot

For science!

Well, it had to happen some time, I guess. A friend tagged me on Facebook in the “ice bucket challenge” to raise funds for the ALS Association. It’s gone massively viral: post a video of yourself getting soaked in ice water, donate to ALSA, and nominate more folks to do the same. So far, it’s raised more than $70 million, and it’s not slowing down yet.

My grandfather died of ALS, so I’m all in favor of funding research to find a cure. But as a working biologist, the idea of financing research in spurts of social media enthusiasm worries me a little. As Felix Salmon notes at Slate:

You need to fund scientists year in and year out; throwing a large grant at them in 2014 and then going away would probably end up causing more harm than good. As a result, most of this money will (and should) probably end up simply sitting on the ALS Association balance sheet, maybe earning some modest rate of interest, getting doled out very slowly over many years.

In terms of bang for the buck, then, giving money to the ALS Association is not much better than giving it to Harvard. Rather than being front-loaded and effective, it’s going to be back-loaded and (sadly, given the results of the $100 million that the ALS Association has spent to date) probably ineffective.

The real foundation of science in the U.S. is funding agencies like the National Science Foundation and the National Institutes of Health. And those agencies have had a rough decade.

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