This spider is doing very well in an urbanized environment, thanks for asking

Spider with lil' spiders

Nephilia plumipes. Photo by Henry Oon.

Urbanization is one of the most dramatic changes humans make to natural habitats. Cities are concentrations of tall buildings, paved landscape, air pollution, and everything else that we do to make life easier for ourselves. But some living things do quite well in these highly altered conditions—think rats and cockroaches, but also red foxes and crows. As the Popular Science blog Eek Squad notes, there’s a new entry on that list: golden orb spiders, Nephila plumipes.

Lowe and colleagues found the city-dwelling arachnids were bigger than their country kin, and the most fertile spiders were found in neighborhoods with the highest socioeconomic status.

Why? The most likely explanation is that cities are warmer, which can lead to bigger invertebrates, and there’s more prey available. The latter is partly because of leaf litter and food for the prey, but it’s also because of a city-related scourge: Artificial light at night. Large spiders were found nearby, or living on, structures like light posts. Insects are drawn to sources of light at night, which could mean more meals for spiders living under bright lights in the big city.

Note that this isn’t necessarily an evolutionary change in response to urban habitats—the spiders probably just find conditions much more favorable in the city, and grow bigger as a result. But that change in resource availability could certainly lead to evolutionary changes over the long term. Go check out the whole Eek Squad post, and have a look at the original scientific article, which is freely available on PLOS ONE.

Population geneticists to Nicholas Wade: You know nothing of our work!

Okay, I’m paraphrasing in that headline, but only barely. From Science Insider:

A best-seller by former New York Times science writer Nicholas Wade about recent human evolution and its potential effects on human cultures has drawn critical reviews since its spring publication. Now, nearly 140 senior human population geneticists around the world, many of whose work was cited in the book, have signed a letter to The New York Times Book Review stating that Wade has misinterpreted their work.

The letter is online, and it doesn’t mince words:

Wade juxtaposes an incomplete and inaccurate account of our research on human genetic differences with speculation that recent natural selection has led to worldwide differences in I.Q. test results, political institutions and economic development. We reject Wade’s implication that our findings substantiate his guesswork. They do not.

We are in full agreement that there is no support from the field of population genetics for Wade’s conjectures.

To those of us who’ve been complaining about Wade’s misappropriation of basic population genetics in support of his ideas about what people of different races may or may not be “adapted” to do, this is the equivalent of that scene from Annie Hall, except with more than a hundred Marshall McLuhans. Updated to add: The full list of 139 folks who signed the letter is posted here.

Sometimes, life is kinda like that. Hat tip to Jennifer Ouellette for the Science Insider story.

Updated to add: See also coverage by Nature, with some choice quotes from signatories; and by Jennifer Raff, who writes, “A strong blow has been dealt to scientific racism today.” Also, from Ed Yong:

Selecting for a butterfly of a different color

Bicyclus anynana 20110217 022654 5455M.JPG

Bicyclus anyana in its low-key natural look. Photo by Gilles San Martin, via Wikimedia Commons

Via NPR: a paper published online this week ahead of print at PNAS reports the results of an artificial selection experiment that changed butterflies’ wings from brown to blue.

We used artificial selection on a laboratory model butterfly, [Bicyclus] anynana, to evolve violet scales from UV brown scales and compared the mechanism of violet color production with that of two other Bicyclus species, Bicyclus sambulos and Bicyclus medontias, which have evolved violet/blue scales independently via natural selection.

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Pangolins are weird, adorable … and very endangered

Pangolins, or scaly anteaters, are delightfully weird. They have many of the adaptations we associate with anteaters—powerful front claws for breaking into anthills, a narrow snout for nosing into broken-open anthills, long tongues and sticky saliva for slurping up ants*—plus a sleek coat of overlapping scales. And, as you’ll see in this clip from the BBC’s The Life of Mammals, they’re (kind of) bipedal!

Pangolins are so different from other mammals, in fact, that all eight species are in a single genus Manis, which is the only genus in the family Manidae. As of this week the IUCN classifies every species in that family of weird adorable mammals as endangered, critically endangered, or vulnerable to extinction—because, apparently, they’re also pretty tasty.

As a review published in this week’s issue of Science describes in detail, we’re in the middle of the sixth mass extinction (that we know about) since life began on Earth, this one caused by the changes we’ve made to the planet. Pangolins are hardly going to be the only potential victims of that mass extinction—they’d be about 2% of the 322 terrestrial vertebrates estimated to have gone extinct since 1500.

(Sad hat-tip to Alex Wild.)

* Or termites, or other insects that hang out in burrows or rotting wood.

This boring-looking grass can occupy an extra 10,000 square miles, thanks to a helpful fungus

Mutualisms, in which two or more species provide each other with services or resources that they can’t produce on their own, are everywhere you find living things. Mutualists offer protection, help transport pollen, and provide key nutrients.

Even when a mutualist’s services aren’t absolutely vital, they can help make stressful environments tolerable. That’s the insight behind a new study that finds the help from one group of mutualists could allow an unremarkable-looking species of grass to colonize more than 25,000 square kilometers (almost 10,000 square miles) of territory where it otherwise wouldn’t survive.

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Fossil hunting with the Brain Scoop

We’re big fans of Emily Graslie’s natural history video series The Brain Scoop. The latest episode goes right to the source of the museum specimens that usually take center stage—a fossil hunting expedition.

Watch the whole thing, and you’ll learn some nifty paleontology jargon, like:

“It’s called the 18-inch layer.”

“Is it because it’s 18 inches?”

“Yeah.”

Scientists at work among the Joshua trees

When he’s not dismantling racist pseudoscience, Chris Smith studies the evolutionary ecology of species interactions. Willamette University sent along a videographer on Chris’s last field trip to study Joshua trees and the moths that pollinate them in central Nevada, and the result is now posted on Vimeo. It’s mainly geared toward showcasing how Willamette undergraduate students participate in the fieldwork, but I’d say it makes the desert look mighty good, too.

A guide to the science and pseudoscience of A Troublesome Inheritance, part III: Has natural selection produced significant differences between races?

This is the third in a series of guest posts in which Chris Smith will examine the evolutionary claims made in Nicholas Wade’s book A Troublesome Inheritance. You can read part I here, and part II here. Chris is an Associate Professor of Evolutionary Ecology at Willamette University. He uses population genetic approaches to understand coevolution of plants and insects, and he teaches the interdisciplinary course “Race, Racism, and Human Genetics” with Emily Drew.

A Troublesome Inheritance was published in 2014 by Penguin Books. Cover image via Google Books.

This spring former New York Times science writer, Nicholas Wade, released his latest book on human evolution, A Troublesome Inheritance: Genes, Race, and Human History. In it, Wade argues that genetic studies completed in the eleven years since the Human Genome Project was completed reveal real and important differences between human races. Unsurprisingly, the book’s release has been met with a sharply divided critical reception.Whereas the book has been widely embraced by those on the political right, and by the white identity movement, it has been panned by anthropologists, evolutionary biologists, and population geneticists. For the last two weeks at Nothing in Biology Makes Sense, I’ve been looking in depth at the literature that Wade uses to support his ideas. Last week I considered Wade’s argument that natural selection acting on the MAO-A gene – a neurotransmitter implicated in aggression and impulsivity – has led to behavioral differences between races. This week I will consider Wade’s larger claim that natural selection has produced numerous differences between races.

Throughout the book Wade continually repeats the mantra that natural selection on humans has been “recent, copious, and regional.” It would be hard to find an evolutionary biologist that would disagree with these rather vague pronouncements. Indeed, there are a multitude of studies showing that natural selection has acted on humans, and there is persuasive evidence that selection has caused evolutionary changes in human populations as we have adapted to diverse environments over the course of the last several thousand years (see, for example, Yi et al., 2010).

However, scratching the surface reveals that when he says that natural selection has been “recent, copious, and regional,” what Wade actually means is that natural selection has been “radical, complete, and racial.” By Wade’s account, natural selection has dramatically reshaped the human genome, producing major differences between races. This much more dramatic interpretation is entirely unsupported by the literature, however. In truth, Wade vastly overstates the portion of the human genome that shows evidence for natural selection, and where there has been recent natural selection acting on humans, its effect has primarily been to create genetic differences between members of the same race, and similarities between people of different races.

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Friday coffee break: Meeting David Attenborough, the best case ever for keeping your samples organized, and hope against the frog-killing fungus

birds

Here’s what we’ll be talking about while we’re waiting in line for a latte.

From Noah: The BBC’s new nature documentary host had an embarrassing meeting with her most famous predecessor.

From Sarah: A proposed bill of rights for science students, and terrifying news about increasing use of the strongest antibiotics as bacteria evolve to resist them.

From CJ: The NIH found some smallpox samples stashed in an old storage room. Oops? And meet the coywolf.

From Jeremy: There may be some hope that amphibians can develop immunity to the infectious fungus that’s been devastating global frog and salamander populations. And arctic shorebirds are shifting their nesting dates to accommodate warmer temperatures.

A guide to the science and pseudoscience of A Troublesome Inheritance, part II: Has natural selection favored violent behavior in some human populations?

This is the second in a series of guest posts in which Chris Smith will examine the evolutionary claims made in Nicholas Wade’s book A Troublesome Inheritance. You can read part I here. Chris is an Associate Professor of Evolutionary Ecology at Willamette University. He uses population genetic approaches to understand coevolution of plants and insects, and he teaches the interdisciplinary course “Race, Racism, and Human Genetics” with Emily Drew.

A Troublesome Inheritance was published in 2014 by Penguin Books. Cover image via Google Books.

Last week at Nothing In Biology Makes Sense, I began critiquing Nick Wade’s latest book, A Troublesome Inheritance. The book has produced a firestorm of criticism, largely because it argues that evolution has produced significant cultural and behavior differences between races.

Wade makes many sweeping claims, among them: that natural selection has made the English inherently fiscally prudent and more likely to defer gratification by saving for tomorrow, that events early in the history of Judaism caused the Jews to evolve features predisposing them to careers in banking, and that genetic variation in certain neurochemicals has made Africans inherently more violent.

Wade hangs these seemingly bizarre conclusions on the mantle of modern population genetics, which he claims confirms the existence of ‘three primary races,’ that have evolved real and significant cultural differences between them. By heavily referencing the scientific literature, Wade manages, as Mike Eisen put it, to “give the ideas that he presents… the authority of science… What separates Wade’s theories – in his own mind – from those of a garden variety racist is that they are undergirded by genetics.”

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