J Pardo

O primeiro maxilar de "pelicossauro" encontrado na América do Sul. #FossilFriday

As with Venezuela, I would feel a lot better if even one or two of the hot takes on the war with Iran appearing in my feed came from Iranians.

To add, liver (regardless of source) is not actually a substantially cheaper option. Beef liver is only slightly cheaper than ground beef. Chicken livers are only slightly cheaper than chicken thighs or quarters.

I enjoy organs meats but the idea these are economic choices in 2026 is just not true.

FAQ for NSF Graduate Research Fellowship Program (NSF GRFP) return without review (RWR)

NSF's FAQ about Graduate Research Fellowship applications returned without review (RWR) ... does not inspire confidence, I have to say www.nsf.gov/funding/info...

There have in fact been a lot of Palaeozoic papers published in Nature and Science during this period of time, but many have not named new taxa. e.g. in early tets, many papers on prev. described taxa (Tiktaalik, Elspistostege, Acanthostega, etc) but only a handful of new ones (Parmastega, Gaiasia)

It's not that similarly important faunas aren't present in other regions, but key taxa out of those sites were already named before the period of time these statistics represent, even though important studies on, say, Burgess Shale animals have appeared in Nature and Science in this interval of time

A huge part of this overall pattern is driven by unique insights into mammal and bird origins thanks to the Liaoning lagerstatten. Additional major insights clearly come from the Cambrian lagerstatten at Chengjiang and the Silurian-Devonian transition in south China. Critically important localities.

This specific map here illustrates a specific pattern of historical worker bias. There are plenty of papers in Nature and Science reporting on new specimens or studies of historical specimens, but in most cases they are not NAMING those species. Strong bias in favor of new localities/regions.

Early synapsids from the Cisuralian (lower Permian) Pedra de Fogo Formation, Parnaíba Basin, Brazil: the first definitive South American “pelycosaurs” The paleotropics of Euramerica provide nearly our entire picture of Permo–Carboniferous terrestrial tetrapod evolution. The geographic sampling bias inherent in this record obscures important event...

Early synapsids from the Cisuralian (lower Permian) Pedra de Fogo Formation, Parnaíba Basin, Brazil: the first definitive South American “pelycosaurs”: Journal of Vertebrate Paleontology: Vol 0, No 0 - Get Access www.tandfonline.com/doi/full/10....

Early synapsids from the Cisuralian (lower Permian) Pedra de Fogo Formation, Parnaíba Basin, Brazil: the first definitive South American “pelycosaurs” The paleotropics of Euramerica provide nearly our entire picture of Permo–Carboniferous terrestrial tetrapod evolution. The geographic sampling bias inherent in this record obscures important event...

Novo artigo quentinho, recém saído do forno com @jdpardo.bsky.social . Nada menos que os primeiros "pelicossauros" do Gondwana. www.tandfonline.com/doi/full/10.... +

Useful affiliation for them, that would give them access to the flagship facilities in Amherst.

I call this "Operation Starvard"

Some of this might be the depositional environment: we have mostly focused effort on a fossil lacustrine/sabka system that has abundant fish and amphibians but relatively rare amniotes. More field effort will clarify this. But for now we can say they were there. And that's a step forward.

One important one is that large synapsids do seem to be rare. We do not see abundant neural spines of Dimetrodon, which is common in the early Permian of North America. Additionally, we have only identified two fragmentary synapsids of over ~1000 vertebrate fossils, so synapsids are very rare.

What does this mean about biogeography? Hard to say at the moment, but we do show that synapsids were present in Gondwana by the later parts of the early Permian. There was some diversity, and that diversity is probably consistent with some of the diversity seen in North America, with some caveats.

We report here a few very fragmentary fossils from northeast Brazil that we can definitively assign to synapsids: a maxilla from a carnivorous sphenacodontid and an impression of a trunk vertebral centrum and arch (no spine) which resembles edaphosaurs. Not much, but a first glimpse.

Synapsids are an important part of this story...when and where did therapsids originate? Were early synapsids restricted to the tropics or were they also present at higher latitudes? But a lack of fossils has really limited our ability to even ask these questions.

So, sampling from Gondwana gives us an external check on whether these patterns are global or are regional. but we have only just started to characterize these Gondwanan assemblages, which include a mix of typical North American forms and unexpected surprises.

Part of this story has always been the origin & diversification of synapsids (mammal forerunners). We have a relatively coherent story of the origin of hypercarnivory & herbivory as part of terrestrialization of ecosystems across this equatorial transect, but this ignores most of the world.

One big outstanding question we have had for a long time is that our best picture of the Carboniferous-Permian transition, and the diversification of amniotes, comes from a narrow span of equatorial Pangaea, mostly North America and West/Central Europe. (pic from Pardo et al. 2020)

Early synapsids from the Cisuralian (lower Permian) Pedra de Fogo Formation, Parnaíba Basin, Brazil: the first definitive South American “pelycosaurs” The paleotropics of Euramerica provide nearly our entire picture of Permo–Carboniferous terrestrial tetrapod evolution. The geographic sampling bias inherent in this record obscures important event...

New paper with @cisneros.bsky.social and others. We report the first pelycosaur-grade synapsid fossils from South America, which happen to also be the oldest synapsids from Gondwana.

www.tandfonline.com/doi/full/10....

Cambrian preservation window

🧵 This gets at a pet peeve of mine: the term “literature review” itself.

The main reasons we discuss “the literature” are: 1) to establish a puzzle or controversy, 2) relatedly, lay out alternative explanations or interpretations, and 3) create scaffolding for your arguments.

Argument can be made that fandom has evolved to fill some of the same social roles as religious identification. Criticism of a media product becomes criticism of a the fundamental identity of the individual, hence the rankling.

A covarion model for phylogenetic estimation using discrete morphological datasets https://pubmed.ncbi.nlm.nih.gov/41728927/

He was always smiling. He loved his family and his cats. His absence will leave a giant hole in the field. He will be missed.

I've known Hans since I was a little high school kid at the Carnegie. We were never especially close but we had a few collaborations here and there and a few more on the go. He had an enthusiasm and curiosity that is a rare thing in our science.

Noooooo

This is such a great game.

Big cichlid personality in a manageable cichlid size. Such a great fish.