Sallan uses big data analytics to study macroevolution, with a particular focus on palaeoichthyology.[10] She uses data mining to identify why some species of fish persist whilst others die off. She joined the University of Pennsylvania in 2014.[11] She leads a large research lab, which includes undergraduate and graduate students.[12] In 2015, she developed a dataset of fish fossils with then undergraduate student Andrew Galimberti.[1] Their analysis showed that during the Devonian period vertebrates gradually increased in size, obeying Cope's rule. She has continued to study the Hangenberg event, finding small-bodied species with rapid reproduction dominate post-extinction communities.[13] She investigated the fossils of the Aetheretmon and found how ray-finned fishes got their tail fins, which are distinct from the tails of land animals.[14] The fossils were recovered from Scotland, and included some of the smallest (3 cm long) and least studied species.[14]
Sallan compiled a comprehensive database of 3,000 fish fossils found between 360 and 480 million years ago.[15] By investigating these fossils, Sallan found that the earliest vertebrate fossils were found near the shore, perhaps due to stronger skeletons due to crashing waves.[16] She studied 31,526 fish species ad found the fastest species formation rates occurred in the coldest oceans.[17] Cold water fish form new species at twice the rate of tropical fish.[17][18] She was named the Martin Meyerson Assistant Professor in Interdisciplinary Studies at the University of Pennsylvania in 2017.[19] The position is for an "outstanding faculty member whose pursuits exemplify the integration of knowledge".[19]
Public engagement
Sallan was one of fifteen people to be selected as a TED fellow in 2017.[20] In April 2017 she delivered a talk entitled "How to win at evolution and survive a mass extinction".[21] She developed a TEDed class on why fish were fish shaped, and why they didn't swim upside down.[22][23] She was featured in the popular science book The Ends of the World, written by Peter Brannen.[24] In 2018 Sallan was awarded the University of Chicago Medical and Biological Sciences Distinguished Service Award.[3]
In 2019, Sallan was named as one of 10 TED Senior Fellows.[25] She gave a second TED Talk, "A brief tour of the last 4 billion years (dinosaurs not included)" at TEDSummit 2019 in Edinburgh, Scotland[26]