It’s going to be a long semester

Tuesdays I have a morning class and an afternoon lab; sandwiched in between was a discipline meeting. I think I’m plum wore out today.

Just to make it more awful, the first genetics assignment is due tomorrow, and I made an awful hash of it, trying to juggle multiple textbook editions, so the students are all confused. So I made an announcement that the assignment is basically cancelled, ignore everything I said, and I’ll come in tomorrow with a whole new problem set that we’ll work on together. What a mess. I’m exhausted just thinking of sorting it all out.

A whole lot of chompin’ and sexin’ going on

This is a beautiful video about the arachnids of Uruguay — great videography and information, and some spectacular closeups of spiders in action. They do seem to spend a lot of time murdering insects and sucking them down, and the sex scenes, especially in the sexually dimorphic species, can be graphic and moderately distressing — tiny males scurrying up to the abdomens of huge females, it’s like trying have sex with a wall topped with fangs that can descend when you’re done and kill you.

It’s all still pretty, and now I want to visit South America. I’ve been to Ecuador, but that was before I discovered the wonders of spiders. I should go again, except…damn this legal weight on my shoulders.

Everyone needs more training to deal with racists

Adam Rutherford is coming out with a new and timely book, How to Argue with a Racist, expected here in the US in early February. I’ve already pre-ordered a copy, and if you’re interested, you can get a taste of the story in The Guardian.

In the 19th century, Darwin’s half-cousin Francis Galton and others tightened their scientific arguments for race though, as Darwin noted, no one could agree on how many races there actually were, the range being between one and 63. Galton was an amazing scientist, and a stunning racist. The most delicious irony about him is that the field he effectively established – human genetics – is the branch of science that has demonstrated unequivocally that race is not biologically meaningful. Modern genetics clearly shows that the way we colloquially define race does not align with the biology that underpins human variation. Instead, race is a cultural taxonomy – a social construct. This doesn’t mean it is invalid or unimportant, nor does it mean that race does not exist. Humans are social animals, and the way we perceive each other is of paramount importance. Race exists because we perceive it.

That’s one message I wish I could get across to all the so-called “scientific” racists. The consensus of real, honest science is that the artificial categories people assign to races don’t exist as biological phenomena. You only find it in the pages of racist ideologues like Charles Murray or hothouse niches on the internet for dishonest cranks like Steve Sailer. Or right-wing think-tanks. Or misinformed YouTubers who got millions of views by parroting bigotry.

I think this book ought to be required reading for journalists and other media spokespeople who seem to be responding to the rise of racism among people with power with nothing but rank credulity and reporting that just echoes the biases without criticism. Maybe the Democratic presidential nominee, whoever it might be, ought to read it to be prepared for debates with our racist president.

The one that got away…in the Mesozoic

It was a bad day for both the squid, Plesioteuthis, and the Rhamphorhynchus that was skimming over the water, trying to snag dinner. The squid got stabbed by a sharp fang, and the reptile lost a tooth and a meal. We know this because of the beautiful fossil found with a broken off tooth preserved in its mantle.

Plesioteuthis subovata from the Late Jurassic Solnhofen Archipelago. An adult specimen, 28 cm long, preserved with ink sac and duct, arm-head complex, well-preserved mantle musculatures (transverse striation) and a pterosaur tooth. (B) Close-up of the 19 mm long, slightly curved Rhamphorhynchus muensteri tooth crown under normal light. (C) Ultraviolet (UV) light reveals that the tooth apex is partially covered with now phosphatized mantle tissue.

Ouch.

Direct evidence of successful or failed predation is rare in the fossil record but essential for reconstructing extinct food webs. Here, we report the first evidence of a failed predation attempt by a pterosaur on a soft-bodied coleoid cephalopod. A perfectly preserved, fully grown soft-tissue specimen of the octobrachian coleoid Plesioteuthis subovata is associated with a tooth of the pterosaur Rhamphorhynchus muensteri from the Late Jurassic Solnhofen Archipelago. Examination under ultraviolet light reveals the pterosaur tooth is embedded in the now phosphatised cephalopod soft tissue, which makes a chance association highly improbable. According to its morphology, the tooth likely originates from the anterior to middle region of the upper or lower jaw of a large, osteologically mature individual. We propose the tooth became associated with the coleoid when the pterosaur attacked Plesioteuthis at or near the water surface. Thus, Rhamphorhynchus apparently fed on aquatic animals by grabbing prey whilst flying directly above, or floating upon (less likely), the water surface. It remains unclear whether the Plesioteuthis died from the pterosaur attack or survived for some time with the broken tooth lodged in its mantle. Sinking into oxygen depleted waters explains the exceptional soft tissue preservation.

So now we know that Pterosaurs ate soft-bodied cephalopods.

I wouldn’t have recognized this spider from last week!

Before I left for the Twin Cities this weekend, I’d fed the spider colony fat juicy waxworms, and they fell upon them furiously. Today I checked on them, and boy were there a lot of bloated, indolent spiders lounging about in their webs, reluctant to even move. One surprise…I took a peek at Yara, who I’ve photographed before, and the change was striking, not just in her size, but in her pigment patterns.

Look how dark she is! This isn’t just the lighting, either — I tinkered a fair bit to get good illumination. Compare it to the previous photo, where she’s much lighter in color, and I would have said she was one of the more lightly pigmented members of the colony. Now I’m wondering how rapidly they can change color and what prompts it, especially since I’ve been following pigment development in the babies.

I was also looking at cobwebs today. There might be some potential for student projects here.

My wife went to Colorado and all I got was… #SpiderSunday

Mary has been away the last few weeks, helping Skatje and Kyle handle a ravening, demanding 15-month old, Iliana. She finally got back home last night, and she brought me a present! It was a spider. No one is surprised.

Well, I was, a little bit. Spiders show so much variation — I’m pretty sure this is Steatoda triangulosa, as it’s obviously a theridiidid, and it’s got that pretty pair of zig-zag stripes down the abdomen, but it’s so golden, and it’s got more zigs than I usually see in S. triangulosa here in Minnesota, and the patterns break up in a messy and different way. Species are so goddamned complicated. Why did I ever leave my nice, inbred, isolated zebrafish?

Anyway, she was guarding a nest in my daughter’s garage, and Mary brought back 6 egg sacs, all of the fluffy type we see with S. triangulosa. Most, probably all, are hatched out, but I’ll find out when I take them into the lab later.

Spidercloth!

I need this:

It’s spidercloth, a single piece of silky fabric made from silk drawn from a million spiders. It might be a little bit labor intensive.

To produce this unique golden cloth, 70 people spent four years collecting golden orb spiders from telephone poles in Madagascar, while another dozen workers carefully extracted about 80 feet of silk filament from each of the arachnids. The resulting 11-foot by 4-foot textile is the only large piece of cloth made from natural spider silk existing in the world today.

So I can’t pick up a spidercloth cloak at Target?

We’re going to have to figure out the chemistry, and we also have to figure out the machinery in spinnerets.

Of course, spending four years to produce a single textile of spider silk isn’t very practical for scientists trying to study the properties of spider silk or companies that want to manufacture the fabric for use as a biomedical scaffold or an alternative to Kevlar armor. Several groups have tried inserting spider genes into bacteria (or even cows and goats) to produce silk, but so far, the attempts have been only moderately successful.

Part of the reason it’s so hard to generate spider silk in the lab is that it starts out as a liquid protein that’s produced by a special gland in the spider’s abdomen. Using their spinnerets, spiders apply a physical force to rearrange the protein’s molecular structure and turn it into solid silk.

Well? Get right on that!

WWII was comprehensible as adaptations of the lineages in question. Christ.

I guess Richard Dawkins has limits on where he’ll allow the Intellectual Dork Web to take him. This is a conversation between Dawkins and Bret Weinstein, from a Pangburn debate a few years ago, where Weinstein rambles insanely about World War II as an exercise in population genetics, as if “German”, “Jew”, and “Russian” are distinct, non-overlapping sets of alleles marching off to replace each other.

…you had the Fatherland effectively raping Mother Russia … what this was was a lineage level phenomenon in which a population [Germans] went after two other populations [Jews and Russians] …understood from the perspective of German genes, vile as these behaviors were, they were completely comprehensible from the level of fitness.

That is nuts. “German genes”…what “German genes” acquired an advantage by murdering their neighbors? This is extreme reductionism assembled on a framework of simplistic and false assumptions. It is embarrassing that a biologist would flaunt his ass this nakedly.

One good thing about it is that at least Richard Dawkins demonstrates some good sense. He looks very uncomfortable during Weinstein’s monolog, and manages to utter a hesitant, mild rebuke of the former Evergreen College professor.

I think nationalism might be an even greater evil than religion. And I’m not sure that it’s actually very helpful to talk about it in Darwinian terms.

It was a net gain for Evergreen to get rid of that guy.

The creationist Paul Nelson reviewed the debate, and sad to say, chose to chide Dawkins for being insufficiently Darwinian…because Nelson seems to share with Weinstein a cartoonish version of evolution. Good work, Weinstein, you’ve got the Discovery Institute on your side.

Watch the planet breathe

This is a dramatic video of arctic ice growing and shrinking.

It was presented at Davos, as if those rich assholes matter. We should spend less effort trying to persuade the wealthy to do the right thing, and more effort stripping the wealthy of their power. Let’s make the rich irrelevant!