Easy. Their harassing behavior affects the evolution of females. This isn’t sexual selection, it’s just that the juvenile females are disguising themselves with male plumage to escape harassment. These birds, white-necked jacobins, are typically sexually dimorphic, but juvenile females maintain a male-like coloration, because females with adult female coloration face more aggressive assaults from males. Adopting the male coloration allows them to feed uninterrupted, while putting on the sexy female green coat brings on a plague of annoying, obnoxious males.

Ornamentation is typically observed in sexually mature adults, is often dimorphic in expression, and is most apparent during breeding, supporting a role for sexual selection in its evolution. Yet, increasing evidence suggests that nonsexual social selection may also have a role in the evolution of ornamentation, especially in females. Distinguishing between these alternatives remains challenging because sexual and nonsexual factors may both play important and overlapping roles in trait evolution. Here, we show that female ornamentation in a dichromatic hummingbird, the white-necked jacobin (Florisuga mellivora), cannot be explained by sexual selection. Although all males are ornamented, nearly 30% of females have male-like plumage. Remarkably, all juveniles of both sexes express ornamented plumage similar to adult males (androchromatism), but 80% of females acquire non-ornamented plumage (heterochromatism) as they age. This unique ontogeny excludes competition for mates as an explanation for female ornamentation because non-reproductive juveniles are more likely to be ornamented than adults. Instead, avoidance of social harassment appears to underlie this female-limited polymorphism, as heterochrome taxidermy mounts received more aggressive and sexual attention than androchrome mounts from this and other hummingbird species. Monitoring electronically tagged birds at data-logging feeders showed that androchrome females accessed feeders more than heterochrome females, presumably because of reduced harassment. Our findings demonstrate that ornamentation can arise purely through nonsexual social selection, and this hypothesis must be considered in the evolution of not only female-limited polymorphism but also the spectacular ornamentation often assumed to result from sexual selection.

They’re evolving to be able to eat dinner in peace.

Boy birds should be ashamed of their behavior, is all I can say. They can’t even leave a taxidermy dummy alone!

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Falk et al., 2021. Male-like ornamentation in female hummingbirds results from social harassment
rather than sexual selection. Current Biology 31, 4381–4387. https://doi.org/10.1016/j.cub.2021.07.043

I tell my intro biology students this on Day One:

Fantastic success, everyone! Two of the pairs of spiders featured in my spider porn video from last week have produced egg sacs! Stri7 & Stri4, and Stri2 & Stri5, to be precise. This is huge. It may be the start of, finally, a self-sustaining colony. I’ve been struggling with this for the past few years — I get a few thriving spiders, a few egg sacs, and then over the winter they die off and I need to replenish the stocks in the spring with wild-caught adults. This is no way to do genetics. Well, it is, but that’s a different kind of genetics than I want to do.

Now I can start making plans. It will be about a month before spiderlings emerge, and then another month or two (depending on how well my fortified fruit fly diet works) to reach adulthood, which means I could have a Gen IV by Hallowe’en, or Thanksgiving at the outside. Exciting! I could be doing crosses by spring term!

Also, right now I’ve got so many spiders and spiderlings I have exceeded my lab’s capacity. In another first, while in previous years I have raided my garage for new spiders, today I took a container of about 50 Steatoda triangulosa spiderlings and released them into my garage. Sorry, babies, I can’t take care of you all, so you’re going to have to forage for yourself in the hard cruel world. Winter is coming, grow up fast.

I should look up from the spiders now and then. I did not know what was happening to forests.

Global trade and climate change are poised to make the spread and severity of arboreal plagues and pestilence worse. The hills around Syracuse are silhouetted with pale ash trees slain by emerald-colored borers. Ancient bristlecone pines out West are succumbing to bark beetle outbreaks triggered by rising temperatures. As many as 1 in 6 trees native to the Lower 48 states are at risk of extinction.

I should know. We bought a house 20 years ago that had a yard full of impressive trees, which we’ve watched steadily decline. Every few years it seems the city splashes another one with neon paint and we’re told it has to come down. But there’s hope! Science rides to the rescue, maybe! The article is about the American Chestnut, and how it’s been wiped out by a fungus.

All it takes is one gene.

The fungus infecting chestnut trees thrives by secreting a chemical called oxalic acid, which kills cells and allows the pathogen to feast on the dead tissue. But many other plants, including bananas, strawberries and wheat, avoid that fate by producing an enzyme called oxalate oxidase that breaks down the toxin.

By 2014, Powell and Maynard successfully added the wheat gene to chestnuts and were growing infection-resistant trees. The pair dubbed one line Darling 58, in honor of Herb.

Many plants use oxalate oxidase as a defense mechanism. It catalyzes the oxidation of oxalic acid into CO₂ and peroxides — reactive oxygen species. Is that going to have a side effect? I don’t know. Barley makes multiple forms of oxalate oxidase, and it doesn’t seem to harm beer production.

“Making a transgenic tree — I hate to say it like this, but it isn’t that hard,” Newhouse said. The most difficult hurdle for Darling 58, he said, is winning regulatory approval.

Well. This is sort of true. Making transgenic organisms is relatively easy nowadays, EXCEPT…the difficult part is figuring out what gene to use, and since most traits have complex origins, and since the expression of the gene is going to have multiple effects on the organism, it’s difficult to predict all of the consequences. There are good reasons regulatory approval is tough to get.

But in this case, they seem to have found a relatively simple way to confer fungus resistance on a tree, and it’s been tried experimentally, and they have successfully produced healthy, blight resistant chestnut trees. However, I think uncertainty about possible outcomes is a good reason to go slow, and regulatory agencies are doing the right thing by putting the brakes on the process.

There are also bad reasons for resisting the transgenic trees, and there seem to be a lot of people blocking it. Their primary argument is this weird idea that “natural” mechanisms like breeding hybrid trees are somehow “better” than transgenic methods — this is the same reasoning that has led to GMO labeling in our grocery stores, as if somehow the fact that an agricultural scientist has intentionally tweaked a plant is bad, while wholesale, random interbreeding of varieties is more pure. I don’t get it. Don’t people realize that all of the crop plants producing your food have been extensively modified by centuries or millennia of intentional manipulation of their genomes? Everything in the supermarket is a mutant, GMO or non-GMO. I’d argue that the genetically modified plants have undergone less drastic changes than those produced the old-fashioned way.

…Powell countered that crossbreeding transfers far more genes between species. “Genetic engineering is actually a less-risky procedure than a lot of things that we’ve done in the past,” he said. “We are very precise. We’re only moving one, two — just a small number of genes into the tree.”

That the changes are small are not a reason to dismiss regulatory oversight, of course. The reason they can use only one or two genes is that they have specifically selected target genes of very large effect.

Of course, re-creating vast chestnut forests would also be a huge effect.

So that’s where the weird speech patterns come from: Tucker Carlson is Jiminy Glick, fictional comedic character.

i noticed the similarities about a year ago but remained silent. today the dam finally burst pic.twitter.com/Pwf3E9OQA6

— John Kerr (@JohnnyHeatWave) August 19, 2022

It’s uncanny.

The big difference is that Glick didn’t lie as much as Carlson. Science magazine went through the full transcript of one of Carlson’s recent tirades, and almost everything Tucker Carlson said about Anthony Fauci this week was misleading or false. I never watch Carlson’s show, so I had no idea how unhinged and divorced from reality his opinions have become. A taste:

Carlson asserted Fauci had committed very serious crimes and said he apparently engineered the single most devastating event in modern American history. Carlson, infamous for assailing people’s looks, also called Fauci a an even tinier version of the Dalai Lama and a Stalinist midget.

Carlson seems to relish criticisms of his comments, which inevitably draw more attention to him and his show. But at the risk of playing into his hand, Science fact-checked his criticisms of Fauci. The analysis shows Carlson took facts out of context and cited long-debunked studies or reports to attack Fauci. He also repeatedly blamed Fauci and other scientists for changing their minds based on new evidence—the bedrock of scientific progress. In Carlson’s calculus, such reversals equal lying.

Obviously, Fauci has committed no crimes, especially not serious ones, and did not engineer the COVID pandemic (which, I thought, Fox News belittled anyway — now it’s the single most devastating event in modern American history?) His ideas about Fauci’s appearance are his to hold, but I don’t think there’s anything Stalinist about him, and hey, what’s wrong with looking like a Tibetan or being a little person anyway?

The article goes through Carlson’s claims line by line and shows that they’re bogus. It’s astonishing that he’s the flagship commentator for a news organization. It’s almost as if Fox has nothing to do with “news”.