We speak to Chase Brownstein, runner-up of the 2025 Biology Letters Early Career Researcher Competition for the research paper Night lizards survived the Cretaceous–Palaeogene mass extinction near the asteroid impact
Tell us about yourself and your research article
I am a third year PhD candidate at Yale University in the Department of Ecology and Evolutionary Biology, where I also graduated college in 2023. I am super interested in reconstructing deep time evolutionary history using phylogenetics.
I actually got the idea for our paper on night lizard evolution when I was doing a study abroad in Paris during my junior year of undergrad. I remember sleeping in this tiny bunk bed and getting this idea at about 3am in the morning that a time-calibrated tree of xantusiid night lizards (which are just really, really awesome-looking animals) that incorporated fossils would be so cool. I had just started writing our 2023 paper on lamprey evolution (Brownstein and Near, 2023; https://www.cell.com/current-biology/fulltext/S0960-9822(22)01918-2) in the courtyard of the small school we were lodging in, so I think tip-dated phylogenies were on my mind. By tip-dating, I mean using fossils as actual species in the time-calibrated tree, not just using them to enforce minimum age bounds on the common ancestors of living species.
Xantusiid night lizards themselves are a group of fewer than 40 species of lizards only found in North America, Central America, and Cuba. They are actually closely related to skinks among lizards, but last share a common ancestor with other lizards perhaps more than 125 million years ago. So, they are what we like to call a long naked branch: not many species, and not very closely related to anything. What's even cooler is the present distribution and fossil record of night lizards suggests that the common ancestor of living species might have survived the asteroid impact that killed the dinosaurs in the blast zone.
What we were able to come up with in a seminar led by two professors on my committee (Thomas Near, Martha Muñoz) was a tip-dated phylogeny of these really odd lizards that (1) demonstrated they did in fact survive the asteroid impact that killed the non-avian dinosaurs despite being only found right in the immediate blast zone and (2) that the low clutch sizes observed in living species actually represent the ancestral condition. This work wouldn't have been possible with my collaborators on this project!
Did you expect to be a finalist in our competition? And do you recommend that other early career researchers enter this year’s competition?
I didn't! This was really just a fun article to put together and I totally recommend folks enter!
What’s next for you and your work?
A whole bunch! Making phylogenies of a bunch of big groups of charismatic vertebrates is taking center stage in my current research. I am also still in love with fossils and am working on a bunch of exciting projects involving extinct species.
And finally, do you have any advice for upcoming generations of scientists in your field?
Keep curious! There's no better way to make sure the lighting strikes you than wandering in an open field, and the same is true in my opinion for research. If you don't keep curious, you will never stumble into something interesting!
The 2026 competition is now open and will run until Tuesday 31 March. Please see our terms and conditions before entering or contact the editorial office with your questions.
Photo credit: Chase Brownstein
