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And for a response to those challenges, Shubin looks back to starting out in the field, as a TA for Stephen Jay Gould

Shubin recounts his decision to focus on the tetrapod transition to land, and the plan of paleontology to look for fossils that might capture that transition

Basically, at one point in the stratigraphy we have lobe-finned fishes, a little higher (more recently) we have terrestrial tetrapods… what’s in between?

Shubin’s early-90s startup funding was enough to cover Pennsylvania turnpike tolls (LOL) to get him and his students to Devonian rocks in the “Catskills Formation” exposed by highway cuts

(Growing up in central Pennsylvania, I actually went fossil-hunting on highway cuts about the same time, not sure it was this same stratum— I found some nice mollusks, no groundbreaking transitional vertebrates)

When the Catskill formation didn’t yield what Shubin was looking for, he zeroed in on another Devonian formation in the Canadian Arctic, which he only found described in passing in an oil/gas exploration report

(Great old school digging-in-the-library story there)

Some photos of truly desolate field-camp sites in the course of this Arctic hunt, tents lost in the wind, casual mention of polar bear hazards

And credit to an undergrad assistant who found a trove of promising fossils, captured in a totally fortuitous landscape photo… then YEARS of excavation

The first Tiktaalik skeleton was discovered snout-first, Shubin says he recognized it as fish bone, not rock, because of the texture

“This is 2004, there’s an intelligent design trial going on in Pennsylvania” incredible evolution lore crossover

Tiktaalik in cladogram with a lobe-finned fish and two Devonian tetrapods — not exactly a “missing link” but a cousin

It was a partial skeleton a first, Shubin’s team only got a femur a couple years ago!

And they found it fully in the surface with the skeleton, and both femora, exposed by wind weathering — the next day camp got hit with a “polar cyclone” and had to be evacuated

(I am barely clinging to comprehension of the skeletal anatomy thanks to TAing mammalogy fully two decades ago)

Shubin’s walking us through (ha) a reconstruction of the hip joint that’s still work In Prep.

“Every time you bend your wrist, every time you shake your hand, you can thank lobe-finned fish”

“When you’re a fish biologist, you look at this [photo of Albert Einstein] and see a big, fat, bipedal, big-brained fish.”

I think that’s a “yes” to my question bsky.app/profile/jbyo...

Shubin closes with a reminder of the vital importance of shared evolutionary history in basic biomedical research: we’re learning how to cure human disease thanks to work on fruit flies, worms, and even fish