I’ve been naughty. I haven’t been keeping up with my intended schedule of one video per week. But finally I got something done.
There have been lots of distractions, but honestly? This is tough for me. There are days I don’t want to look at my face or hear my voice, and making these videos compels me to sit down and wrestle with my lack of charisma. I’ll keep plodding along, mainly as therapy — I do enjoy the process, it’s just that final step of subjecting it to the eyeballs of the world that is hard.
er, there ARE spiders that “thwip” though (Scytodidae).
“Real spiders don’t THWIP!”? What next, they don’t have secret identities, live with their Aunt May, and secretly crush on their best friend, who no-so-secretly crushes on their super-hero alter ego? Go on, crush all our fantasies, PZ. Crush them all.
Then I suppose Spider-Man doesn’t really do this, either? Man, you scientist types are real sticklers for, you know, reality and stuff.
@1 Ichthyic,
The image of Spider-Man spitting his web and swinging building-to-building holding on with his teeth will now never leave my brain.
Pretending to lack charisma is a very charismatic thing to do …
“Did that come out of your butt?”
PZ, congratulations on another very good video. I’ll stop short of “excellent” only because you didn’t give us any literature references.
So I’m not sure whether numbers on the branches of the phylogeny that you showed are bootstrap support values. If they are, or even if they are Bayesian posterior probabilities, 47% support for Araneae from these data is suggestive but not firm, while 10% support for monophyly of Uraraneida is very dubious. So you were right to suggest in the video that Uraraneida was probably a paraphyletic group.
Looking for the tree you posted, I did not find it, but came across these two back-to-back papers:
Bo Wang, Jason A. Dunlop, Paul A. Selden, Russell J. Garwood, William A. Shear, Patrick Müller & Xiaojie Lei. 2018. Cretaceous arachnid Chimerarachne yingi gen. et sp. nov. illuminates spider origins. Nature Ecology & Evolution 2: 614–622 (2018)
Diying Huang, Gustavo Hormiga, Chenyang Cai, Yitong Su, Zongjun Yin, Fangyuan Xia & Gonzalo Giribet. 2018. Origin of spiders and their spinning organs illuminated by mid-Cretaceous amber fossils. Nature Ecology & Evolution 2: 623–627 (2018) |
In the phylogenies inferred in the latter paper, Uraraneida is often paraphyletic.
Another point that worried you in your video was multiple origins of complex structures like spinnerets and the flagellum. I suspect that the reconstructions of ancestral states for those traits were done assuming that change back and forth was equally likely. But loss of a complex trait is much easier than gaining it. Taking that into account, the ancestral reconstructions might be instead that the trait was gained once and lost multiple times.
I will consider it a personal affront if your work does not result in a real-life Spider-Man.
The literature reference was added this morning — it is the Huang paper.
There is a Web comic called Spinnerette where the protagonist gets bitten by a radioactive spider a la Spider-Man but the effects are somewhat more dramatic in that she grows 4 extra limbs and the web comes from her abdomen. I read it for a while but kind of lost interest.