Science online, don't drink the sapa edition

Wood thrush, or mercury-poisoning canary? Photo by dermoidhome.

• New at Nothing in Biology Makes Sense! Making sense of humans' role in the extinction of North America's big ice age mammals and the evolution of multicellularity.
• Splenda suddenly doesn't seem so bad. The ancient Romans created the world's first artificial sweetener. It was a lead compound. And we can still see the resulting poisoning in Roman skeletal remains.
• Not a feeding frenzy; more like a bridge club. Observational evidence suggests that sharks have social lives.
• Silvery spring. Increasing—and worrying—levels of mercury have been detected in common songbirds in the northeastern U.S.
• Sleep on it. Separating good ideas from bad ones requires taking time to not think about them.
• Black, apparently. Reconstructing the color of Archaeopteryx feathers.
• However, the Moon must still hit your eye like a big pizza pie for amore as we know it. Life as we know it probably doesn't require the Moon as we know it.
• In your pants. Are modern grooming habits creating an extinction crisis?
• Infant mortality, mental illness, and drug use. Just some of the bad things that increase along with greater income inequality.
• Calibrated unfocusedness. Jumping spiders judge distances using blurry vision.

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Counterfactualizing for truth

Something kind of incredible is going on over at Ta-Nehisi Coates's place: Bouncing off some typically reprehensible and ahistorical remarks by Ron Paul—who apparently thinks that (1) the U.S. Civil War was started by the North, (2) for the express purpose of ending slavery, even though (3) nonviolent means, such as "compensated emancipation," could have accomplished that end—Coates is not simply rounding up the contrary evidence, but actually trying to work out whether and how a nonviolent end to the "peculiar institution" could have worked. It's like a Harry Turtledove novel, except fascinating and good and informative.

Nevertheless, the saving of people is, indeed, a noble goal, and Paul is not without at least the rudiments of a case. Enslaved black people were constructed into an interest representing $3 billion. ($70-75 billion in 21st century money.) But including expenditures, loss of property, loss of life (human capital,) the war, according to Ransom, costs $6.6 billion.

The numbers are clear--the South's decision to raise an army, encourage sedition among its neighbors, and fire on federal property, was an economic disaster for white America. Moreover, the loss of 600,000 lives, in a war launched to erect an empire on the cornerstone of white supremacy and African slavery, was a great moral disaster for all corners of America.

In the most crude sense, it would have been much "cheaper" for the government to effect a mass purchase. But how?

Spoiler alert: compensated emancipation doesn't look very practical, especially considering that Southern slaveholders were pretty damned hostile to the idea. But getting to that conclusion is enlightening, and the discussion in Coates's famous comments section is as well worth your time as the posts. ◼

Baby steps versus long jumps: The "size" of evolutionary change, and why it matters

Evolution can make leaps—but how frequently? Photo by Flavio Martins.

Does evolutionary change happen in big jumps, or a series of small steps? The question may seem a little esoteric to non-scientists—how many mutations can dance on the head of a pin?—but it has direct implications for how we identify the genetic basis of human diseases, or desirable traits in domestic plants and animals.

That's because the evolutionary path by which a particular phenotype, or visible trait, first evolved in a population is closely related to the genetics that underlie the trait in the present. Phenotypes that arose in a single mutational jump will probably remain connected to one or a few genes with large effects; phenotypes that evolved more gradually do so because they are created by the collective action of many genes. So what kind of evolutionary change is most common will determine which kind of gene-to-phenotype relationships we should expect to find.

In an excellent recent review article for the journal Evolution, Matthew Rockman, a biologist with the Department of Biology and Center for Genomics and Systems Biology at New York University, makes the case that the era of genomics has, so far, been much too focused on finding genes of large effect. Fortunately, Rockman also sees the beginnings of a new movement towards acknowledging the importance of small-effect genes—one which may ultimately make genomic association studies more useful.

Change happened

Between this and a kick-ass State of the Union address, I'm feeling pretty damned optimistic, all of a sudden. It's a weird sensation. I think I may be a bit light-headed. ◼

I want to see mountains again ...

Watch this on full screen mode, or don't watch it at all. All of a sudden, I need an excuse to go west.



Via Line Out. ◼

Nothing in Biology Makes Sense: Making sense of the origins of multicellularity

Experimental evolution of multicellularity. Photo by Nothing in Biology Makes Sense!

In this week's new post at the group blog Nothing in Biology Makes Sense!, Sarah Hird discusses the recently published experimental evolution study that used laboratory yeast to tackle one of the biggest questions in reconstructing the history of life:

Some of the biggest questions in evolutionary biology deal with the origin of life. For example, if I go back one generation, I find my parents. Two generations, my grandparents. Ten generations are human beings who may or may not have looked like me. Five hundred thousand are, oh, I don’t know. Maybe a bipedal hominid? Anyway, if we continue going backward like this, we inevitably get to time zero and encounter some big-time questions that can really cause a brain to cramp up.

I promise you, if you read the whole thing, you will not experience brain cramps. Quite the opposite, in fact.

In other news, Nothing in Biology Makes Sense! has put out a call for guest contributors. If you work in biology—anything from medicine to plant breeding—and you've been thinking about giving this science blogging thing a try, send us an e-mail!  ◼

Winter weather warning

Between the fact that it's been a record-setting-ly mild winter, and the fact that I usually take the bus, I'd gone nearly seven months living in Minnesota without this happening.

Time to cross another item off the ol' bucket list.  ◼