Research
Dinosaur Growth
I use bone histology to study the evolution of growth at multiple spatial and temporal scales. Annual growth marks analogous to tree rings allow for estimation of an individual fossil's age at death and rate of growth through life. Some of my studies using this technique have been published in Science (2015, 2023), The Journal of Paleontology, Paleogeography, Paleoclimatology, Paleoecology, and the Journal of Systematic Paleontology.
evolution of bone at the Tissue and cellular scales
Fossil bone records the size, shape, density and orientation of bone cells and neurovasculature as they were in life, giving us a rich window into cellular biology and histology in deep time. I aim to discover form-function relationships at the cellular and histological scales to infer physiological traits such as growth and metabolic rates in extinct animals. Some of my studies using this technique have been published in Science, Bone, and Biology Letters.
evolution and paleoecology of tooth DEVELOPMENT
The rate of tooth formation and replacement is tied to a species' ecology and displays broad variation across reptiles. Periodic incremental lines in tooth dentine can be used to reconstruct these rates in extinct animals, allowing us to reconstruct paleoecology and diet. Much of my research using this technique has focused on sauropods and theropods as published in PLOS One, and I recently published a meta-analysis of tooth formation rates in Biology Letters.
mid-cretaceous faunal turnover
Around 100 million years ago, faunal turnover in North America occurred, involving the extinction of several archaic lineages and the appearance of many modern lineages. This occurred during a time when flowering plants were first radiating across the continent, a land bridge between Asia and North America was forming, and dramatic sea level increase was occurring that would later bisect North America into eastern and western subcontinents. My research seeks to untangle the effects of these events on the complex faunal turnover that occurred at the time, and has been published in the Journal of Vertebrate Paleontology, Bulletin of the Peabody Museum of Natural History, and twice in Paleogeography, Paleoclimatology, Paleoecology.
Evolution and function of unusual anatomical structures
Part of my research deals with the basic description and interpretation of anatomical structures that are new to science, including the surprisingly complex hyobranchial apparatus (bones of the tongue and throat) of some dinosaurs, which I published with colleagues in The Zoological Journal of the Linnean Society, the evolution and development of osteoderms ('skin-bones') in some sauropod dinosaurs, which I have published on with colleagues in Nature Communications and twice in the Journal of Vertebrate Paleontology, or the unusual ribs of marine reptiles known as mosasaurs, which I have published in Palaeontology.
I recently published a monographic treatment of a Late Jurassic sauropod skull referable to Brachiosaurus (D’Emic and Carrano, 2020). Click here to download the nexus file from that paper’s phylogenetic analysis, which is the latest iteration of my titanosauriform sauropod dinosaur matrix first published in 2012.