On the eating of one's words

Back in the day, when I was an undergrad at the University of St. Thomas, I was still very much a vert paleo chauvinist, just getting my toes wet in the Decorah. I'd been going through some of the old journals and textbooks, and was dismayed by the lack of coverage of vertebrates (well, dinosaurs). Everything seemed to be about invertebrates, particularly those with some kind of useful economic function (biostratigraphy) or with extensive fossil records permitting the testing of pet evolutionary hypotheses. While discussing this with my professors, I said something to the effect of "A brachiopod can't bring you love. A trilobite, maybe, but not a brachiopod."

Two decades later, I am the proud namesake of a brachiopod, specifically (in both senses) Ivdelinia (Ivdelinia) tweeti Blodgett et al. 2022: "The species name is in honor of Justin S. Tweet, paleontologist dedicated to the documentation, preservation, and study of National Park Service fossils." Thank you, Robert, Valeryi, and Vince!

A handsome fellow, isn't it? (Scale bar is 1 cm; Figure 6 in Blodgett et al. 2022).

I. tweeti comes from the Emsian-age (late Early Devonian) rocks of the Shellabarger Limestone in Denali National Park. The formation itself is also newly minted in Blodgett et al. (2022), and is part of the Mystic sequence of the Farewell Terrane. If you're not familiar with the geology of Alaska, it's almost entirely made up of bits and pieces of crust that collided with each other during the Phanerozoic. Characteristics such as biogeography have been used to reconstruct where the crustal fragments came from and the timing of their journeys. In this case, the Shellabarger Limestone brachiopods and other invertebrates show more of an affiliation to northeast Russia than to North America, indicating the fragment rifted from Siberia before arriving at what became Alaska (Blodgett et al. 2022).

References

Blodgett, R. B., V. V. Baranov, and V. L. Santucci. 2022. Two new late Emsian (latest Early Devonian) pentameridine brachiopods from the Shellabarger Limestone (New Formation), Shellabarger Pass, Denali National Park and Preserve, south-central Alaska. New Mexico Museum of Natural History and Science Bulletin 90:73–83.