Evolutionary biologist · Data scientist

Ava Ghezelayagh

AI + Science Postdoctoral Scholar
Data Science Institute & Department of the Geophysical Sciences, University of Chicago

I am an AI + Science Postdoctoral Scholar at the Data Science Institute and the Department of the Geophysical Sciences at the University of Chicago, where I work with David Jablonski. My research applies genomic data to explore historical patterns relevant to evolutionary theory and to the conservation of aquatic biodiversity, especially in the face of today’s heightened extinction risk.

At UChicago I use machine learning to build a comprehensive evolutionary framework for living and extinct bivalves: mussels, oysters, scallops and their relatives. I completed my BS and PhD in Ecology & Evolutionary Biology at Yale University in the lab of Thomas Near. There I specialized in the systematics, phylogenomics and macroevolution of fishes, from the radiation of spiny-rayed fishes after the end-Cretaceous extinction to species limits in North American darters.

Contact: ghezelayagh@uchicago.edu

Publications

2026

  1. The macroevolutionary impact of an innovation reversal

    Brownstein, …, A Ghezelayagh, …

    bioRxiv preprint, 2026

    Maps repeated losses of the swim bladder across spiny-rayed fishes and traces their timing through the Paleocene–Eocene hyperthermals.

    Read paper

  2. Linking fluvial barriers and habitat specialization in the evolution of microendemism in riverine fishes

    MF Stokes, D Kim, BW Albanese, DJ MacGuigan, MB Davidson, A Ghezelayagh, TJ Near

    Evolution 80 (9), 2030, 2026

    In the Holiday Darter species complex, specialization to high-elevation streams on metamorphic rock, together with knickpoints that block dispersal between tributaries, created the isolation that produced microendemic lineages.

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  3. Alternative pathways into the deep sea: patterns in Bivalvia

    A Ghezelayagh, SM Edie, D Jablonski

    Proceedings of the Royal Society B, 2026

    Deep-sea endemic lucinid clams arrived piecemeal through as many as 16 independent entries, whereas mussels entered only four times and then diversified in place. The contrast may trace back to differences in ancestral feeding mode.

    Read paper UChicago NewsPhys.org

  4. Genomic and phenotypic delimitation of species in a temperate aquatic biodiversity hotspot

    DJ MacGuigan, A Taylor, A Ghezelayagh, JE Wood, JW Simmons, JM Mollish, TJ Near

    Systematic Biology, 2026

    Combines genomic and morphological data to delimit species of freshwater fishes in eastern North America, one of the world's temperate hotspots of aquatic diversity.

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2025

  1. Comparative species delimitation of a biological conservation icon

    A Ghezelayagh, JW Simmons, JE Wood, T Yamashita, …, TJ Near

    Current Biology 35, 398–406, 2025

    Genomic and morphological evidence shows that the Snail Darter, the fish at the centre of a landmark 1970s Endangered Species Act fight over the Tellico Dam, is a population of the Stargazing Darter rather than a distinct species.

    Read paper Free full text Yale NewsSmithsonian

2024

  1. Synergistic innovations enabled the radiation of anglerfishes in the deep open ocean

    CD Brownstein, KL Zapfe, S Lott, RC Harrington, A Ghezelayagh, A Dornburg, TJ Near

    Current Biology 34 (11), 2541–2550, 2024

    Anglerfishes moved into the midnight zone 50–35 million years ago, during a period of global warming. Sexual parasitism, size dimorphism and the loss of adaptive immunity worked together to fuel their radiation.

    Read paper Free full text Yale EEB

2023

  1. Species-level recognition and redescription of the Kentucky Arrow Darter, Etheostoma spilotum Gilbert (Percidae: Litocara)

    MR Thomas, RE Blanton, A Ghezelayagh, TJ Near

    Bulletin of the Peabody Museum of Natural History 64 (1), 39–80, 2023

    Meristic, morphometric and genetic data support recognising the threatened Kentucky Arrow Darter as a distinct species.

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  2. Phylogenomics of Acanthomorpha: from ancient radiations to the tips of the tree

    A Ghezelayagh

    PhD dissertation, Yale University, 2023

    Phylogenomic studies of spiny-rayed fishes, from Mesozoic and Cenozoic radiations down to species delimitation.

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2022

  1. Prolonged morphological expansion of spiny-rayed fishes following the end-Cretaceous

    A Ghezelayagh, RC Harrington, ED Burress, MA Campbell, JC Buckner, …, TJ Near

    Nature Ecology & Evolution 6 (8), 1211–1220, 2022

    A time-calibrated phylogeny built from ultraconserved elements and sampling 91% of acanthomorph families shows that the major lineages arose before the K–Pg extinction, but their body shapes expanded long afterward.

    Read paper Free full text

  2. Accelerated diversification explains the exceptional species richness of tropical characoid fishes

    BF Melo, BL Sidlauskas, TJ Near, FF Roxo, A Ghezelayagh, …

    Systematic Biology 71 (1), 78–92, 2022

    1,288 ultraconserved element loci across 293 species reveal that Neotropical characoid fishes reached their exceptional richness through accelerated recent diversification.

    Read paper Free full text

In the news

Get in touch

I'm always happy to talk about phylogenomics, fishes, bivalves, or machine learning in evolutionary biology.

ghezelayagh@uchicago.edu