Integrative Paleoecology
An animal's diet is one of the most critical aspects of their ecology and can help clarify hunting/foraging strategies, where an animal persists, how animals interact (via competition and/or predation), and vulnerabilities to climate change, predation, food scarcity, and/or extinction. The use of paleoecological proxies, including stable isotopes and dental wear patterns, have improved our understanding of mammalian diets beyond analyses of the size and shape of skull, dental, and skeletal features (i.e. morphology, which reveals potential but not realized diets).
You are what you eat and drink (plus a few per mil). In short, what an animal eats is incorporated into their tissues (e.g., stable isotopes), can affect the microscoping and macroscopic wear on teeth (e.g., dental microwear textures, dental mesowear, dental macrowear), and ultimately can affect the skull and dental features an animals exhibits (e.g., their morphology, via evolutionary processes). While most paleontologists focus on morphological features, we supplement morphological studies with other tools that can move beyond what an animal was suited to eat (based on morphology) and infer what an animal actually ate during its lifetime.
All of the tools mentioned can individually provide insight into the ancient ecology of predators and their prey and have required extensive testing on extant mammals to establish their efficacy. When possible, we employ multiple tools to test prevailing morphological hypotheses and clarify the ancient ecology of Cenozoic mammals. We collaborate with students and colleagues from institutions across the globe who are interested in using our surface profiler (confocal microscope) and also collaborate with colleagues who have expertise in finite element analysis to test relationships between form (morphology) and function (diet). For example, tapirs were re-visited in a recent study (in collaboration with an international team of tapir and hominin experts) to assess the function of sagittal crests (the large crest where jaw muscles attach to aid in chewing) in relation to diet - of relevance to the diet of early hominins. See our work in Scientific Reports, and relevant press.
Tools employed by the DREAM Lab. Image credit: Larisa DeSantis
Multi-proxy Approaches
Stable isotopes, dental microwear textures, dental mesowear, dental macrowear, morphology (including FEA), radiometric dating, and more, are all useful tools and techniques aimed at assessing the ecology and behavior of ancient life. Due to the presence of both C3 and C4 trees/shurbs and both C3 and C4 grasses in Australia, DeSantis first employed DMTA methods as part of a collaborative study on the giant short-faced kangaroo Procoptodon goliah. They identified P. goliah as a C4 browser, a consumer of salt-bush, which made them more vulnerable to extinction due to their need to consume water from watering holes (which may have been fewer in number, further apart, and dangerous due to predation by crocodiles and/or humans). Collaborative work on Cuddie Springs, led DeSantis and co-authors to conclude that climate change, notably aridification, was a potential driver of megafaunal extinctions. Without the combined use of multiple tools, the ecology of numerous animals would not be possible (as is the case for nearly all of the Australia work, plus work at Rancho La Brea). The DREAM Lab is one of the few research labs in the world where students are able to be trained in stable isotope analysis, dental microwear texture analysis, dental mesowear methods, morphological methods, and more (including work with databases; see Macroecology, below).
See Predators Past and Present
See An Arid World
Dental microwear textures of a modern coyote from Alaska, a surface included in DeSantis et al. 2019 (Current Biology). Image credit: Larisa DeSantis
Paleoecological Methods
Before any of the stable isotope, dental microwear, or dental mesowear/macrowear methods can be employed on fossils, we must first demonstrate their efficacy in extant mammals (where we can observe their diet and are aware of local climatic conditions). For example, oxygen isotopes can provide unique insights regarding past climates, including how arid it was in the past—but some animals track aridity better than others. We work to identify how carbon and oxygen isotopes from a variety of fossil taxa and modern mammals record their local environment.
The formation of dental microwear has also been debated. Some researchers attributing microscopic wear patterns on teeth as being caused by the food consumed by animals (e.g., phytoliths in grass or the textural properties of food, tough vs. hard) while others suggest grit on food in the primary driver. We investigate this debate via:
experimental studies—e.g., feeding pigs different diets with different grit loads (see Human Evolution, below)
model organisms—e.g., studying koalas who ate leaves lacking phyotliths yet yield dental microwear indicative of tough food consumption
field studies—e.g., studying animals throughout their range to record if microwear is tracking climate (rainfall) or diet
Due to rapid climate change over the past century, we also study modern and historic extant mammals to clarify dietary responses to climate change.
See An Arid World
Former VU graduate students working on macroecological research. Image Credit: Joe Howell/Vanderbilt University.
Macroecology
Paleoecological and macroecological studies have sought to understand how animals adjusted their spatial distributions, physiology, and/or behavior to cope with ecosystem change in the past. A species may change its geographic range to track its preferred climatic conditions, or it may remain in the same location and adapt its physiology or behavior to compensate for environmental change, or a species may do both: move and adapt. Alternatively, species not able to move or adapt may go extinct locally or as a species. In March of 2018, Melissa Paridi (a NSF postdoctoral scholar) and I began clarifying how climate and environmental changes over the past 35,000 years impacted mammalian communities in North America by integrating DREAM Lab tools with the niche modeling expertise of Pardi.
As part of graduate courses (Paleoecological Methods, Macroecology and Biogeography, and Macroevolution) we conduct primary research that resulted in peer-reviewed publications. For example, we demonstrate niche conservatism over deep time and suggest that intrinsic life history variables may help buffer families from dramatic fluctuations in range size (PLoS ONE). Additionally, we assessed the ubiquity of Rapoport’s rule (i.e. species have broader latitudinal ranges at higher mean latitudes) in deep time , demonstrating that dramatic cooling (particularly Pleistocene glaciations) was likely responsible for the Rapoport rule patterns we observe today (Biology Letters). Other projects were methods based including work on oxygen as an aridity indicator in Pleistocene North America (Paleobiology), and testing the efficacy of dental microwear (PLoS One).
Finite element analysis models of extant and extinct tapirs. Published in Scientific Reports. Image credit: DeSantis et al. 2020.
Form and Function
Functions (e.g., diet, behavior) are often inferred from morphological forms. For example, wide and narrow muzzles in herbivorous ungulates are correlated with grass and browse (leaf, trees, shrubs) diets, respectively. Functional hypotheses can be tested using modern analogues (extant mammals with skull morphologies and diets that can be quantified) and using finite element analysis (FEA) where biomechanical stresses and strains can be inferred. In collaboration with FEA experts (e.g., Jack Tseng, Alana Sharp, Stephen Lautenschlager and others), we combine FEA and dental microwear texture analysis (DMTA) methods to infer dietary niches and test hypotheses relating to morphological form and function. In collaboration with tapir and hominin experts, we used tapirs as model organisms to understand the relationships between the sagittal crest (which allows for large chewing muscles) and diet—of broad implication to the diet of the hominin Paranthropus boisei (Scientific Reports).
By combining FEA, DMTA, and other tools (e.g., macrowear, morphology) the DREAM team and colleagues have clarified the dietary niches of spotted hyenas from China (Paleobiology) and suggest unique dietary behavior of the marsupial sabertooth Thylacosmilus atrox - a potential soft-organ specialist that may have opened up carcasses and slurped out the guts of its prey (PeerJ).
Image of Paranthropus boisei. Image credit: © Roman Yevseyev.
Human Evolution
It is widely understood that the evolution of our earliest ancestors was strongly influenced by diet, and yet there has been surprisingly strong disagreement about precisely which types of foods they were eating. In particular, it is unclear whether the massive jaws and huge teeth of robust hominins (i.e. humans and our immediate ancestors) evolved to process hard foods like nuts and seeds, or tough, fibrous foods that might have included grasses. An important piece of evidence in this debate comes from the microscopic damage done to teeth by food, and particles of grit that may adhere to food. In collaboration with David Strait (Washington University) and Robert Scott (Rutgers University) we are conducting experiments designed to evaluate how patterns of dental microwear should be interpreted (via a recently funded NSF Biological Anthropology grant). Experiments use suid models (due to the similarity of their teeth to humans) to evaluate the effect of foods with varying toughness and hardness on tooth surfaces, as well as the hardness and size of abrasive particles like sand, seed shell fragments and other very hard plant parts. This, in turn, will allow an evaluation of the causes of damage patterns seen in the teeth of fossil humans, which will in turn allow a more precise assessment of the diets of early humans.
Sled dogs in Fairbanks, Alaska. Image Credit: Larisa DeSantis
Archaeological Studies
Paleontologists are often mistaken for archaeologists, and vice versa. Paleontologists study ancient life while archaeologists study human civilizations (via their artifacts). The DREAM lab enjoys collaborating with archaeologists on a variety of projects, especially when the tools we employ can help reveal the behavior of ancient human civilizations. We have worked in collaboration with archaeologists who specialize on the Andes (in South America), others who work in Tennessee (e.g. Coats-Hines Lichy Site), a team of researchers working in South Africa (in the Cape Flora Biome), and others who work more broadly on human-dog interactions (in North America).
Our collaborations have helped clarify the dietary behavior of humans at Huace Prieta and Paredones mounds in Peru (in collaboration with Tom Dillehay, Tiffiny Tung), documenting some of the earliest maize consumption in the Americas via stable isotopes and dental microwear. In Tennessee, the DeSantis Lab collaborated with Jesse Tune and Michael Waters to complete the faunal and isotopic analysis of the Coats-Hines-Litchy Site which contains mammoths, giant ground sloths, and LOTS of turtles. Human-dog interactions have also been examined with Amanda Burtt, including the degree to which humans provisioned dogs with food. Work in the Cape Flora Biome is currently on-going, work led by Tyler Faith and David Braun.
Relevant Papers & Press (Organized by Methods)
Papers may be listed more than once, under different categories.
(*graduate student, **undergraduate student) Bold = lab members
Integrative Paleoecology
Janis, C.M., Figueirido, B., DeSantis, L.R.G., Lautenschlager, S. 2020. An eye for a tooth: Thylacosmilus was not a marsupial “saber-tooth predator.” Peer J 8:e9346 (https://doi.org/10.7717/peerj.9346)
Featured in National Geographic, Smithsonian, and global news coverage, including Atlas Obscura and the New York Times.
DeSantis, L.R.G. §, Sharp, A.C., Schubert, B.W., Colbert, M.W., Wallace, S.C., Grine, F.E. 2020. Clarifying relationships between cranial form and function in tapirs, with implications for the dietary ecology of early hominins. Scientific Reports 10:8809 (https://doi.org/10.1038/s41598-020-65586-w)
Featured in Vanderbilt News, Notizie Scientifiche, and RPP Noticias.
DeSantis, L.R.G. §, Feranec, R.S., Fox-Dobbs, K., **Crites, J.M., Farrell, A.B., Harris, J.M., Takeuchi, G.T., Cerling, T.E. 2020. Reply to Van Valkenburgh et al. The validity of stable isotope data from tooth enamel to interpreting the ecology of ancient predators and their prey. Current Biology 30:R151-R152 (https://doi.org/10.1016/j.cub.2020.01.011)
Scholtz, E.J.**, DeSantis, L.R.G. §. 2020. Invasive species, not environmental changes, restrict the population and geographical range of the quokka (Setonix brachyurus). Journal of Zoology 311:106-115 (https://doi.org/10.1111/jzo.12765)
Featured by UPI , Futurity, The Epoch Times, and more. Also, this work is being featured on a forthcoming podcast on The Wild Life. See the associated blog we wrote, published in the Journal of Zoology Blog.
Smith, G.J.*, DeSantis, L.R.G. § 2020. Extinction of North American Cuvieronius (Mammalia, Proboscidea, Gomphotheriidae) driven by dietary resource competition with sympatric mammoths and mastodons. Paleobiology 46:41-57 (https://doi.org/10.1017/pab.2020.7)
DeSantis, L.R.G. §, **Crites, J.M., Feranec, R.S., Fox-Dobbs, K., Farrell, A.B., Harris, J.M., Takeuchi, G.T., Cerling, T.E. 2019. Pleistocene megafaunal extinctions, climate change, and mesopredator dietary release. Current Biology 29: 2488-2495 (https://doi.org/10.1016/j.cub.2019.06.059)
Featured in National Geographic, CNN, Smithsonian, LA Times, Ars Technica, and numerous news outlets. Also, see Curiosity Stream's tv documentaries featuring our work: Saber-tooth Brawl (English), Lucha Entre Dientes De Sable (Spanish), and Tops Science Stories of 2019.
*Bradham, J., DeSantis, L.R.G. §, Jorge, M.L.S.P., Keuroghlian, A. 2018. Dietary variability of extinct tayassuids and modern white-lipped peccaries (Tayassu pecari) as inferred from dental microwear and stable isotope analysis. Palaeogeography, Palaeoclimatology, Palaeoecology 499: 93-101 (https://doi.org/10.1016/j.palaeo.2018.03.020)
DeSantis, L.R.G. §, Tseng, J., Liu, J. **Hurst, A., Schubert, B.W., Jiangzuo, Q. 2017. Assessing niche conservatism using a multi-proxy approach: dietary ecology of extinct and extant spotted hyenas. Paleobiology 43: 286-303 (https://doi.org/10.1017/pab.2016.45)
DeSantis, L.R.G. §, Field, J.H., Wroe, S. Dodson, J. 2017. Dietary responses of Sahul (Pleistocene Australia-New Guinea) megafauna to climate and environmental change. Paleobiology Letters - Rapid Communications 43: 181-195 (https://doi.org/10.1017/pab.2016.50)
Rapid Communications are reserved for papers that represent "non-incremental research advancements of broad interdisciplinary interest." Featured in Scientific American and other news outlets including Smithsonian, Forbes, and several others.
**Jones, B.D., DeSantis, L.R.G. § 2017. Dietary ecology of ungulates from the La Brea tar pits in southern California: a multi-proxy approach. Palaeogeography, Palaeoclimatology, Palaeoecology 466: 110–127 (https://doi.org/10.1016/j.palaeo.2016.11.019)
Prideaux, G.J. §, Ayliffe, L.K., DeSantis, L.R.G., Schubert, B.W., Murray, P.F., Gagan, M.K., Cerling, T.E. 2009. Extinction implications of a chenopod browse diet for a giant Pleistocene kangaroo. PNAS 106: 11646-11650 (http://www.pnas.org/content/106/28/11646.full)
Featured in BBC News and several other on-line, print, and radio shows (including PRI).
DeSantis, L.R.G. §, MacFadden, B.J. 2007. Identifying forested environments in Deep Time using fossil tapirs: evidence from evolutionary morphology and stable isotopes. Courier Forschungsinstitut Senckenberg 258: 147-157
Invited contribution to a Special Issue Honoring David L. Dilcher and Jack A. Wolfe titled, Advances in Angiosperm Paleobotany and Paleoclimatic. Featured in Wired Science .
Reviews and/or Method Development
Braun, D., Faith, J. T., Douglass, M., Davies, B., Power, M., Aldeias, V., Conard, N., Cutts, R., DeSantis, L., Dupont, L., Esteban, I., Kandel, A., Levin, N., Luyt, J., Parkington, J., Pickering, R., Quick, L., Sealy, J., Stynder, D. Ecosystem engineering in the Quaternary of the West Coast of South Africa. Evolutionary Anthropology (In revision)
*Larmon, J.T., McDonald, H.G., Ambrose, S., DeSantis, L.R.G. , Lucero, L.J. 2019. A year in the life of a giant ground sloth during the Last Glacial Maximum in Belize. Science Advances 5 (2): eaau1200 (https://doi.org/10.1126/sciadv.aau1200)
Featured in The New York Post, Fox News, Smithsonian, and numerous news outlets.
DeSantis, L.R.G. §, **Alexander, J., *Biedron, E.M., *Johnson, P.S., **Frank, A.S., **Martin, J.M., **Williams, L. 2018. Effects of climate on dental mesowear of extant koalas and two broadly distributed kangaroos throughout their geographic range. PLoS ONE 13(8): e0201962. (https://doi.org/10.1371/journal.pone.0201962)
Featured in EveryONE, PLoS ONE's Blog, and News Channel 5.
*Tanis, B.P., DeSantis, L.R.G., Terry, R.C. 2018. Dental microwear textures across cheek teeth in canids: implications for dietary studies of extant and extinct canids. Palaeogeography, Palaeoclimatology, Palaeoecology 508: 129-138 (https://doi.org/10.1016/j.palaeo.2018.07.028)
DeSantis, L.R.G. §, **Hedberg, C. 2017. Stable isotope ecology of the koala (Phascolarctos cinereus). Australian Journal of Zoology 64: 343-349 (https://doi.org/10.1071/ZO16057)
**Hedberg, C., DeSantis, L.R.G. § 2017. Dental microwear texture analysis of extant koalas: clarifying causal agents of microwear. Journal of Zoology 301: 206-214 (http://onlinelibrary.wiley.com/doi/10.1111/jzo.12413/full)
*Arman, S., Ungar, P., Brown, C., DeSantis, L.R.G., Schmidt, C., Prideaux, G. 2016. Minimizing inter-microscope variability in dental microwear texture analysis. Surface Topography: Metrology and Properties 4: 024007 (http://iopscience.iop.org/article/10.1088/2051-672X/4/2/024007/meta)
Invited contribution for a special issue titled, Exposing the past: what surfaces and their measurement can teach us about extinct species and the lives of ancient people.
DeSantis, L.R.G. § 2016. Dental microwear textures: reconstructing diets of fossil mammals. Surface Topography: Metrology and Properties 4: 023002 (http://iopscience.iop.org/article/10.1088/2051-672X/4/2/023002)
Invited Review Paper for a special issue titled: Exposing the past: what surfaces and their measurement can teach us about extinct species and the lives of ancient people.
DeSantis, L.R.G. §, Schubert, B.W., *Schmitt-Linville, E., Ungar, P., *Donohue, S., *Haupt, R.J. 2015. Dental microwear textures of carnivorans from the La Brea Tar Pits, California and potential extinction implications. Science Series of the Natural History Museum of Los Angeles County 42: 37-52 (https://nhm.org/site/sites/default/files/pdf/contrib_science/lacm-42.pdf)
Invited contribution for a special volume titled, La Brea and Beyond: the Paleontology of Asphalt-Preserved Biotas, in commemoration of the 100th anniversary of the Natural History Museum of Los Angeles County's excavations at Rancho La Brea. Featured in Forbes magazine (Are The Dire Wolves From Game of Thrones Real Animals?).
**Loffredo, L., DeSantis, L.R.G.§ 2014. Cautionary lessons from assessing dental mesowear observer variability and integrating paleoecological proxies of an extreme generalist herbivore. Palaeogeography, Palaeoclimatology, Palaeoecology 395: 42-52 (https://doi.org/10.1016/j.palaeo.2013.12.020)
*Donohue, S.L., DeSantis, L.R.G. §, Schubert, B.W., Ungar, P.S. 2013. Was the giant short-faced bear a hyper-scavenger? A new approach to the dietary study of ursids using dental microwear textures. PLoS ONE 8: e77531 (https://doi.org/10.1371/journal.pone.0077531)
*Yann, L.T., DeSantis, L.R.G. §, *Haupt, R.J., **Romer, J.L., **Corapi, S.E., **Ettenson, D.J. 2013. The application of an oxygen isotope aridity index to terrestrial paleoenvironmental reconstructions in Pleistocene North America. Paleobiology 39: 576-590 (http://dx.doi.org/10.1666/12059)
DeSantis, L.R.G. §, Scott, J.R., Schubert, B.W., *Donohue, S.L., *McCray, B.M., **Van Stolk, C.A., *Winburn, A.A., **Greshko, M.A., **O'Hara, M.C. 2013. Direct comparisons of 2D and 3D dental microwear proxies in extant herbivorous and carnivorous mammals. PLoS ONE 8: e71428 (https://doi.org/10.1371/journal.pone.0071428)
*Haupt, R.J., DeSantis, L.R.G. §, Green, J.L., Ungar, P.S. 2013. Dental microwear texture as a proxy for diet in xenarthrans. Journal of Mammalogy 94: 856-866 (http://dx.doi.org/10.1644/12-MAMM-A-204.1)
DeSantis, L.R.G. § 2011. Stable isotope ecology of extant tapirs from the Americas. Biotropica 43: 746-754. (http://onlinelibrary.wiley.com/doi/10.1111/j.1744-7429.2011.00761.x/full)
MacFadden, B.J. §, DeSantis, L.R.G., Labs Hochstein, J., Kamenov, G.D. 2010. Physical properties, geochemistry, and diagenesis of xenarthran teeth: prospects for interpreting the paleoecology of extinct species. Palaeogeography, Palaeoclimatology, Palaeoecology 291: 180-189 (https://doi.org/10.1016/j.palaeo.2010.02.021)
Schubert, B.W. §, Ungar, P.S., DeSantis, L.R.G. 2010. Carnassial microwear and dietary behaviour in large carnivorans. Journal of Zoology 280: 257-263 (http://onlinelibrary.wiley.com/doi/10.1111/j.1469-7998.2009.00656.x/full)
DeSantis, L.R.G. §, Feranec, R.S., MacFadden, B.J. 2009. Effects of global warming on ancient mammalian communities and their environments. PLoS ONE 4: e5750
Featured in msNBC and numerous other media outlets including Wired Science, Science Now.
Macroecology & Ecology
Badgley, C., Smiley, T.M., Davis, E.B., DeSantis, L.R.G., Fox, D.L., Hopkins, S.B., Jezkova T., Matocq, M.D., Matzke, N., McGuire, J.L., Mulch, A., Riddle, B.R., Roth, V.L., Samuels, J.X., Strömberg, C.A.E., Terry, R., Yanites, B.J. 2017. Biodiversity and topographic complexity: modern and geohistorical perspectives. Trends in Ecology and Evolution 32: 211–226 (http://dx.doi.org/10.1016/j.tree.2016.12.010)
**Veter, N.M., DeSantis, L.R.G. §, *Yann, L.T., *Donohue, S.L., *Haupt, R.J., **Corapi, S.E., *Fathel, S.L., **Gootee, E.K., **Loffredo, L.F., **Romer, J.L., **Velkovski, S. 2013. Is Rapoport's rule a recent phenomenon? A deep time perspective on potential causal mechanisms. Biology Letters 9: 20130398 (http://rsbl.royalsocietypublishing.org/content/roybiolett/9/5/20130398.full.pdf)
DeSantis, L.R.G. §, *Beavins Tracy, R.A., *Koontz, C.S., *Roseberry, J.C., *Velasco, M.C. 2012. Mammalian niche conservation through deep time. PLoS ONE 7: e35624 (https://doi.org/10.1371/journal.pone.0035624)
Featured in the French Tribune (http://frenchtribune.com/teneur/1210846-diversity-best-way-mammals-adapt-environmental-changes), in addition to other on-line media sources.
DeSantis, L.R.G. §, Bhotika, S., Putz, F.E., Williams, K. 2007. Sea-level rise and drought interactions accelerate declines on the Gulf Coast of Florida, USA. Global Change Biology 13: 2349-2360 (http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2486.2007.01440.x/full)
Featured in UPI .
Stable Isotopes
DeSantis, L.R.G. §, Feranec, R.S., Fox-Dobbs, K., **Crites, J.M., Farrell, A.B., Harris, J.M., Takeuchi, G.T., Cerling, T.E. 2020. Reply to Van Valkenburgh et al. The validity of stable isotope data from tooth enamel to interpreting the ecology of ancient predators and their prey. Current Biology 30:R151-R152 (https://doi.org/10.1016/j.cub.2020.01.011)
Scholtz, E.J.**, DeSantis, L.R.G. §. 2020. Invasive species, not environmental changes, restrict the population and geographical range of the quokka (Setonix brachyurus). Journal of Zoology 311:106-115 (https://doi.org/10.1111/jzo.12765)
Featured by UPI , Futurity, The Epoch Times, and more. Also, this work is being featured on a forthcoming podcast on The Wild Life. See the associated blog we wrote, published in the Journal of Zoology Blog.
Smith, G.J.*, DeSantis, L.R.G. § 2020. Extinction of North American Cuvieronius (Mammalia, Proboscidea, Gomphotheriidae) driven by dietary resource competition with sympatric mammoths and mastodons. Paleobiology 46:41-57 (https://doi.org/10.1017/pab.2020.7)
Lundelius, E.L., Thies, K.J., Graham, R.W., Bell, C.J, Smith, G.J.*, DeSantis, L.R.G. 2019. Proboscidea from the Big Cypress Creek Fauna, Deweyville Formation, Harris County, Texas. Quaternary International 530-531:59-68 (https://doi.org/10.1016/j.quaint.2019.11.018)
DeSantis, L.R.G. §, **Crites, J.M., Feranec, R.S., Fox-Dobbs, K., Farrell, A.B., Harris, J.M., Takeuchi, G.T., Cerling, T.E. 2019. Pleistocene megafaunal extinctions, climate change, and mesopredator dietary release. Current Biology 29: 2488-2495 (https://doi.org/10.1016/j.cub.2019.06.059)
Featured in National Geographic, CNN, Smithsonian, LA Times, Ars Technica, and numerous news outlets. Also, see Curiosity Stream's tv documentaries featuring our work: Saber-tooth Brawl (English), Lucha Entre Dientes De Sable (Spanish), and Tops Science Stories of 2019.
*Larmon, J.T., McDonald, H.G., Ambrose, S., DeSantis, L.R.G. , Lucero, L.J. 2019. A year in the life of a giant ground sloth during the Last Glacial Maximum in Belize. Science Advances 5 (2): eaau1200 (https://doi.org/10.1126/sciadv.aau1200)
Featured in The New York Post, Fox News, Smithsonian, and numerous news outlets.
*Bradham, J., DeSantis, L.R.G. §, Jorge, M.L.S.P., Keuroghlian, A. 2018. Dietary variability of extinct tayassuids and modern white-lipped peccaries (Tayassu pecari) as inferred from dental microwear and stable isotope analysis. Palaeogeography, Palaeoclimatology, Palaeoecology 499: 93-101 (https://doi.org/10.1016/j.palaeo.2018.03.020)
*Tune, J.W., Waters, M.R.§, Schmallec, K.A., DeSantis, L.R.G., Kamenove, G. 2018. Assessing the proposed pre-last glacial maximum human occupation of North America at Coats-Hines-Litchy, Tennessee, and other Sites. Quaternary Science Reviews 186: 47-58 (https://doi.org/10.1016/j.quascirev.2018.02.018)
DeSantis, L.R.G. §, **Hedberg, C. 2017. Stable isotope ecology of the koala (Phascolarctos cinereus). Australian Journal of Zoology 64: 343-349 (https://doi.org/10.1071/ZO16057)
DeSantis, L.R.G. §, Field, J.H., Wroe, S. Dodson, J. 2017. Dietary responses of Sahul (Pleistocene Australia-New Guinea) megafauna to climate and environmental change. Paleobiology Letters - Rapid Communications 43: 181-195 (https://doi.org/10.1017/pab.2016.50)
Rapid Communications are reserved for papers that represent "non-incremental research advancements of broad interdisciplinary interest." Featured in Scientific American and other news outlets including Smithsonian, Forbes, and several others.
**Jones, B.D., DeSantis, L.R.G. § 2017. Dietary ecology of ungulates from the La Brea tar pits in southern California: a multi-proxy approach. Palaeogeography, Palaeoclimatology, Palaeoecology 466: 110–127 (https://doi.org/10.1016/j.palaeo.2016.11.019)
*Yann, L., DeSantis, L.R.G. §, Koch, P.L., Lundelius, E.L. 2016. Dietary ecology of Pleistocene camelids: Influences of climate, environment, and sympatric taxa. Palaeogeography, Palaeoclimatology, Palaeoecology 461: 389–400 (https://doi.org/10.1016/j.palaeo.2016.08.036)
*Yann, L., DeSantis, L.R.G. § 2014. Effects of Pleistocene climates on local environments and dietary behavior of mammals in Florida. Palaeogeography, Palaeoclimatology, Palaeoecology 414: 370-381 (https://doi.org/10.1016/j.palaeo.2014.09.020)
Feranec, R.S. §, DeSantis, L.R.G. 2014. Understanding specifics in generalist diets of carnivorans by analyzing stable carbon isotope values in Pleistocene mammals of Florida. Paleobiology 40: 477-493 (http://dx.doi.org/10.1666/13055)
*Yann, L.T., DeSantis, L.R.G. §, *Haupt, R.J., **Romer, J.L., **Corapi, S.E., **Ettenson, D.J. 2013. The application of an oxygen isotope aridity index to terrestrial paleoenvironmental reconstructions in Pleistocene North America. Paleobiology 39: 576-590 (http://dx.doi.org/10.1666/12059)
DeSantis, L.R.G. § 2011. Stable isotope ecology of extant tapirs from the Americas. Biotropica 43: 746-754. (http://onlinelibrary.wiley.com/doi/10.1111/j.1744-7429.2011.00761.x/full)
DeSantis, L.R.G. §, Feranec, R.S., MacFadden, B.J. 2009. Effects of global warming on ancient mammalian communities and their environments. PLoS ONE 4: e5750
Featured in msNBC and numerous other media outlets including Wired Science, Science Now.
Prideaux, G.J. §, Ayliffe, L.K., DeSantis, L.R.G., Schubert, B.W., Murray, P.F., Gagan, M.K., Cerling, T.E. 2009. Extinction implications of a chenopod browse diet for a giant Pleistocene kangaroo. PNAS 106: 11646-11650 (http://www.pnas.org/content/106/28/11646.full)
Featured in BBC News and several other on-line, print, and radio shows (including PRI).
DeSantis, L.R.G. §, Wallace, S.C. 2008. Neogene forest from the Appalachians of Tennessee, USA: geochemical evidence from fossil mammal teeth. Palaeogeography, Palaeoclimatology, Palaeoecology 266: 59-68 (https://doi.org/10.1016/j.palaeo.2008.03.032)
DeSantis, L.R.G. §, MacFadden, B.J. 2007. Identifying forested environments in Deep Time using fossil tapirs: evidence from evolutionary morphology and stable isotopes. Courier Forschungsinstitut Senckenberg 258: 147-157
Invited contribution to a Special Issue Honoring David L. Dilcher and Jack A. Wolfe titled, Advances in Angiosperm Paleobotany and Paleoclimatic. Featured in Wired Science .
See Book Chapters on Publications Page.
Dental Microwear
Louys, J.§, Zaim, Y., Rizal, Y., Aswan, M.P., Trihascaryo, A., Price, G.J., Petherick, A.**, Scholtz, E.**, DeSantis, L.R.G. § Sumatran orangutan diets in the Late Pleistocene as inferred from dental microwear texture analysis. Quaternary International (In press; https://doi.org/10.1016/j.quaint.2020.08.040)
Janis, C.M., Figueirido, B., DeSantis, L.R.G., Lautenschlager, S. 2020. An eye for a tooth: Thylacosmilus was not a marsupial “saber-tooth predator.” Peer J 8:e9346 (https://doi.org/10.7717/peerj.9346)
Featured in National Geographic, Smithsonian, and global news coverage, including Atlas Obscura and the New York Times.
DeSantis, L.R.G. §, Sharp, A.C., Schubert, B.W., Colbert, M.W., Wallace, S.C., Grine, F.E. 2020. Clarifying relationships between cranial form and function in tapirs, with implications for the dietary ecology of early hominins. Scientific Reports 10:8809 (https://doi.org/10.1038/s41598-020-65586-w)
Featured in Vanderbilt News, Notizie Scientifiche, and RPP Noticias.
DeSantis, L.R.G. §, Feranec, R.S., Fox-Dobbs, K., **Crites, J.M., Farrell, A.B., Harris, J.M., Takeuchi, G.T., Cerling, T.E. 2020. Reply to Van Valkenburgh et al. The validity of stable isotope data from tooth enamel to interpreting the ecology of ancient predators and their prey. Current Biology 30:R151-R152 (https://doi.org/10.1016/j.cub.2020.01.011)
Scholtz, E.J.**, DeSantis, L.R.G. §. 2020. Invasive species, not environmental changes, restrict the population and geographical range of the quokka (Setonix brachyurus). Journal of Zoology 311:106-115 (https://doi.org/10.1111/jzo.12765)
Featured by UPI , Futurity, The Epoch Times, and more. Also, this work is being featured on a forthcoming podcast on The Wild Life. See the associated blog we wrote, published in the Journal of Zoology Blog.
Smith, G.J.*, DeSantis, L.R.G. § 2020. Extinction of North American Cuvieronius (Mammalia, Proboscidea, Gomphotheriidae) driven by dietary resource competition with sympatric mammoths and mastodons. Paleobiology 46:41-57 (https://doi.org/10.1017/pab.2020.7)
DeSantis, L.R.G. §, **Crites, J.M., Feranec, R.S., Fox-Dobbs, K., Farrell, A.B., Harris, J.M., Takeuchi, G.T., Cerling, T.E. 2019. Pleistocene megafaunal extinctions, climate change, and mesopredator dietary release. Current Biology 29: 2488-2495 (https://doi.org/10.1016/j.cub.2019.06.059)
Featured in National Geographic, CNN, Smithsonian, LA Times, Ars Technica, and numerous news outlets. Also, see Curiosity Stream's tv documentaries featuring our work: Saber-tooth Brawl (English), Lucha Entre Dientes De Sable (Spanish), and Tops Science Stories of 2019.
Stydner, D.D.§, DeSantis, L.R.G., *Donohue, S.L., Schubert, B.W., Ungar, P.S. 2018. A Dental Microwear Texture Analysis of the Early Pliocene African Ursid Agrotherium africanum (Mammalia, Carnivora, Ursidae). Journal of Mammalian Evolution 26: 505-515 (https://doi.org/10.1007/s10914-018-9436-y)
DeSantis, L.R.G., Fortelius, M., Grine, F., Janis, C., Kaiser, T.M, Merceron, G., Purnell, M.A., Schulz-Kornas, E., Saarinen J., Teaford, M., Ungar, P.S., Žliobaité, I.§ 2018. The phylogenetic signal in tooth wear: what does it mean? Ecology and Evolution (https://doi.org/10.1002/ece3.4541)
*Tanis, B.P., DeSantis, L.R.G., Terry, R.C. 2018. Dental microwear textures across cheek teeth in canids: implications for dietary studies of extant and extinct canids. Palaeogeography, Palaeoclimatology, Palaeoecology 508: 129-138 (https://doi.org/10.1016/j.palaeo.2018.07.028)
*Bradham, J., DeSantis, L.R.G. §, Jorge, M.L.S.P., Keuroghlian, A. 2018. Dietary variability of extinct tayassuids and modern white-lipped peccaries (Tayassu pecari) as inferred from dental microwear and stable isotope analysis. Palaeogeography, Palaeoclimatology, Palaeoecology 499: 93-101 (https://doi.org/10.1016/j.palaeo.2018.03.020)
*Smith, G.J., DeSantis, L.R.G. § 2018. Dietary ecology of Pleistocene mammoths and mastodons as inferred from dental microwear textures. Palaeogeography, Palaeoclimatology, Palaeoecology 492: 10-25 (https://doi.org/10.1016/j.palaeo.2017.11.024)
Green, J.L.§, DeSantis, L.R.G., *Smith, G.J. 2017. Regional variation in the browsing diet of Pleistocene Mammut americanum (Mammalia, Proboscidea). Palaeogeography, Palaeoclimatology, Palaeoecology 487: 59-70. (https://doi.org/10.1016/j.palaeo.2017.08.019)
Featured in Scientific American
DeSantis, L.R.G. §, Patterson, B.D. 2017. Dietary behaviour of man-eating lions as revealed by dental microwear textures. Scientific Reports 7: 904 (https://www.nature.com/articles/s41598-017-00948-5)
Featured in Science and 65+ news outlets including National Geographic, Smithsonian, Discover, Newsweek, The Washington Post, Chicago Tribune, and numerous other radio (e.g., Voice of America, BBC, Futureproof, live-news radio), print, and TV shows (The Daily Planet, Discovery Channel in Canada).
DeSantis, L.R.G. §, Tseng, J., Liu, J. **Hurst, A., Schubert, B.W., Jiangzuo, Q. 2017. Assessing niche conservatism using a multi-proxy approach: dietary ecology of extinct and extant spotted hyenas. Paleobiology 43: 286-303 (https://doi.org/10.1017/pab.2016.45)
DeSantis, L.R.G. §, Field, J.H., Wroe, S. Dodson, J. 2017. Dietary responses of Sahul (Pleistocene Australia-New Guinea) megafauna to climate and environmental change. Paleobiology Letters - Rapid Communications 43: 181-195 (https://doi.org/10.1017/pab.2016.50)
Rapid Communications are reserved for papers that represent "non-incremental research advancements of broad interdisciplinary interest." Featured in Scientific American and other news outlets including Smithsonian, Forbes, and several others.
**Hedberg, C., DeSantis, L.R.G. § 2017. Dental microwear texture analysis of extant koalas: clarifying causal agents of microwear. Journal of Zoology 301: 206-214 (http://onlinelibrary.wiley.com/doi/10.1111/jzo.12413/full)
**Jones, B.D., DeSantis, L.R.G. § 2017. Dietary ecology of ungulates from the La Brea tar pits in southern California: a multi-proxy approach. Palaeogeography, Palaeoclimatology, Palaeoecology 466: 110–127 (https://doi.org/10.1016/j.palaeo.2016.11.019)
**Jones, B.D., DeSantis, L.R.G. § 2016. Dietary ecology of the extinct cave bear (Ursus spelaeus): evidence of omnivory as inferred from dental microwear textures. Acta Palaeontologica Polinica 61 (4): 735–741 (http://dx.doi.org/10.4202/app.00253.2016)
*Arman, S., Ungar, P., Brown, C., DeSantis, L.R.G., Schmidt, C., Prideaux, G. 2016. Minimizing inter-microscope variability in dental microwear texture analysis. Surface Topography: Metrology and Properties 4: 024007 (http://iopscience.iop.org/article/10.1088/2051-672X/4/2/024007/meta)
Invited contribution for a special issue titled, Exposing the past: what surfaces and their measurement can teach us about extinct species and the lives of ancient people.
DeSantis, L.R.G. § 2016. Dental microwear textures: reconstructing diets of fossil mammals. Surface Topography: Metrology and Properties 4: 023002 (http://iopscience.iop.org/article/10.1088/2051-672X/4/2/023002)
Invited Review Paper for a special issue titled: Exposing the past: what surfaces and their measurement can teach us about extinct species and the lives of ancient people.
DeSantis, L.R.G. §, Schubert, B.W., *Schmitt-Linville, E., Ungar, P., *Donohue, S., *Haupt, R.J. 2015. Dental microwear textures of carnivorans from the La Brea Tar Pits, California and potential extinction implications. Science Series of the Natural History Museum of Los Angeles County 42: 37-52 (https://nhm.org/site/sites/default/files/pdf/contrib_science/lacm-42.pdf)
Invited contribution for a special volume titled, La Brea and Beyond: the Paleontology of Asphalt-Preserved Biotas, in commemoration of the 100th anniversary of the Natural History Museum of Los Angeles County's excavations at Rancho La Brea. Featured in Forbes magazine (Are The Dire Wolves From Game of Thrones Real Animals?).
DeSantis, L.R.G. §, *Haupt, R.J. 2014. Cougars’ key to survival through the late Pleistocene extinction: insights from dental microwear texture analysis. Biology Letters 10 (4): 20140203 (http://rsbl.royalsocietypublishing.org/content/10/4/20140203)
Featured in The Economist (print and on-line), National Geographic, and numerous other on-line, print, and radio outlets including MSN UK, Discovery News, ABC News, BBC World Service Radio, Quirks & Quarks (Radio Show, CBC), Scientific America - 60-second Science Podcast and a National Geographic Wild television special called Future Cats.
*Donohue, S.L., DeSantis, L.R.G. §, Schubert, B.W., Ungar, P.S. 2013. Was the giant short-faced bear a hyper-scavenger? A new approach to the dietary study of ursids using dental microwear textures. PLoS ONE 8: e77531 (https://doi.org/10.1371/journal.pone.0077531)
DeSantis, L.R.G. §, Scott, J.R., Schubert, B.W., *Donohue, S.L., *McCray, B.M., **Van Stolk, C.A., *Winburn, A.A., **Greshko, M.A., **O'Hara, M.C. 2013. Direct comparisons of 2D and 3D dental microwear proxies in extant herbivorous and carnivorous mammals. PLoS ONE 8: e71428 (https://doi.org/10.1371/journal.pone.0071428)
*Haupt, R.J., DeSantis, L.R.G. §, Green, J.L., Ungar, P.S. 2013. Dental microwear texture as a proxy for diet in xenarthrans. Journal of Mammalogy 94: 856-866 (http://dx.doi.org/10.1644/12-MAMM-A-204.1)
DeSantis, L.R.G. §, Schubert, B.W., Scott, J.R., Ungar, P.S. 2012. Implications of diet for the extinction of saber-toothed cats and American lions. PLoS ONE 7: e52453 (https://doi.org/10.1371/journal.pone.0052453)
Featured in msNBC, in addition to numerous on-line (e.g., Huffington Post, National Geographic), radio (Up all Night, BBC; As it Happens, CBC) and TV media including a National Geographic Wild special called Future Cats.
Schubert, B.W. §, Ungar, P.S., DeSantis, L.R.G. 2010. Carnassial microwear and dietary behaviour in large carnivorans. Journal of Zoology 280: 257-263 (http://onlinelibrary.wiley.com/doi/10.1111/j.1469-7998.2009.00656.x/full)
Prideaux, G.J. §, Ayliffe, L.K., DeSantis, L.R.G., Schubert, B.W., Murray, P.F., Gagan, M.K., Cerling, T.E. 2009. Extinction implications of a chenopod browse diet for a giant Pleistocene kangaroo. PNAS 106: 11646-11650 (http://www.pnas.org/content/106/28/11646.full)
Featured in BBC News and several other on-line, print, and radio shows (including PRI).
See Book Chapters on Publications Page.
Dental Mesowear
Cohen, J.E., DeSantis, L.R.G. Lindsey, E.L., Meachen, J.A., O’Keefe, F.R., Southon, J.R., Binder, W.J. Dietary stability inferred from dental mesowear analysis in large ungulates from Rancho La Brea and opportunistic feeding during the Late Pleistocene. Palaeogeography, Palaeoclimatology, Palaeoecology (In revision)
DeSantis, L.R.G. §, **Alexander, J., *Biedron, E.M., *Johnson, P.S., **Frank, A.S., **Martin, J.M., **Williams, L. 2018. Effects of climate on dental mesowear of extant koalas and two broadly distributed kangaroos throughout their geographic range. PLoS ONE 13(8): e0201962. (https://doi.org/10.1371/journal.pone.0201962)
Featured in EveryONE, PLoS ONE's Blog, and News Channel 5.
DeSantis, L.R.G. §, Tseng, J., Liu, J. **Hurst, A., Schubert, B.W., Jiangzuo, Q. 2017. Assessing niche conservatism using a multi-proxy approach: dietary ecology of extinct and extant spotted hyenas. Paleobiology 43: 286-303 (https://doi.org/10.1017/pab.2016.45)
**Jones, B.D., DeSantis, L.R.G. § 2017. Dietary ecology of ungulates from the La Brea tar pits in southern California: a multi-proxy approach. Palaeogeography, Palaeoclimatology, Palaeoecology 466: 110–127 (https://doi.org/10.1016/j.palaeo.2016.11.019)
**Loffredo, L., DeSantis, L.R.G.§ 2014. Cautionary lessons from assessing dental mesowear observer variability and integrating paleoecological proxies of an extreme generalist herbivore. Palaeogeography, Palaeoclimatology, Palaeoecology 395: 42-52 (https://doi.org/10.1016/j.palaeo.2013.12.020)
Morphology
Faith, J. T., Braun, D., Davies, B., DeSantis, L., Douglass, M., Esteban, I., Hare, V., Levin, N., Luyt, J., Pickering, R., Power, M., Sealy, J., Stynder, D. Ecometrics and the paleoecological implications of Pleistocene faunas from the western coastal plaines of the Cape Floristic Region, South Africa. Journal of Quaternary Science (In revision).
Janis, C.M., Figueirido, B., DeSantis, L.R.G., Lautenschlager, S. 2020. An eye for a tooth: Thylacosmilus was not a marsupial “saber-tooth predator.” Peer J 8:e9346 (https://doi.org/10.7717/peerj.9346)
Featured in National Geographic, Smithsonian, and global news coverage, including Atlas Obscura and the New York Times.
DeSantis, L.R.G. §, Sharp, A.C., Schubert, B.W., Colbert, M.W., Wallace, S.C., Grine, F.E. 2020. Clarifying relationships between cranial form and function in tapirs, with implications for the dietary ecology of early hominins. Scientific Reports 10:8809 (https://doi.org/10.1038/s41598-020-65586-w)
Featured in Vanderbilt News, Notizie Scientifiche, and RPP Noticias.
Lundelius, E.L., Thies, K.J., Graham, R.W., Bell, C.J, Smith, G.J.*, DeSantis, L.R.G. 2019. Proboscidea from the Big Cypress Creek Fauna, Deweyville Formation, Harris County, Texas. Quaternary International 530-531:59-68 (https://doi.org/10.1016/j.quaint.2019.11.018)
*Tune, J.W., Waters, M.R.§, Schmallec, K.A., DeSantis, L.R.G., Kamenove, G. 2018. Assessing the proposed pre-last glacial maximum human occupation of North America at Coats-Hines-Litchy, Tennessee, and other Sites. Quaternary Science Reviews 186: 47-58 (https://doi.org/10.1016/j.quascirev.2018.02.018)
DeSantis, L.R.G. §, Tseng, J., Liu, J. **Hurst, A., Schubert, B.W., Jiangzuo, Q. 2017. Assessing niche conservatism using a multi-proxy approach: dietary ecology of extinct and extant spotted hyenas. Paleobiology 43: 286-303 (https://doi.org/10.1017/pab.2016.45)
Prideaux, G.J. §, Ayliffe, L.K., DeSantis, L.R.G., Schubert, B.W., Murray, P.F., Gagan, M.K., Cerling, T.E. 2009. Extinction implications of a chenopod browse diet for a giant Pleistocene kangaroo. PNAS 106: 11646-11650 (http://www.pnas.org/content/106/28/11646.full)
Featured in BBC News and several other on-line, print, and radio shows (including PRI).
DeSantis, L.R.G. §, MacFadden, B.J. 2007. Identifying forested environments in Deep Time using fossil tapirs: evidence from evolutionary morphology and stable isotopes. Courier Forschungsinstitut Senckenberg 258: 147-157
Invited contribution to a Special Issue Honoring David L. Dilcher and Jack A. Wolfe titled, Advances in Angiosperm Paleobotany and Paleoclimatic. Featured in Wired Science .
Archaeology
Braun, D., Faith, J. T., Douglass, M., Davies, B., Power, M., Aldeias, V., Conard, N., Cutts, R., DeSantis, L., Dupont, L., Esteban, I., Kandel, A., Levin, N., Luyt, J., Parkington, J., Pickering, R., Quick, L., Sealy, J., Stynder, D. Ecosystem engineering in the Quaternary of the West Coast of South Africa. Evolutionary Anthropology (In revision)
Faith, J. T., Braun, D., Davies, B., DeSantis, L., Douglass, M., Esteban, I., Hare, V., Levin, N., Luyt, J., Pickering, R., Power, M., Sealy, J., Stynder, D. Ecometrics and the paleoecological implications of Pleistocene faunas from the western coastal plaines of the Cape Floristic Region, South Africa. Journal of Quaternary Science (In revision).
*Tune, J.W., Waters, M.R.§, Schmallec, K.A., DeSantis, L.R.G., Kamenove, G. 2018. Assessing the proposed pre-last glacial maximum human occupation of North America at Coats-Hines-Litchy, Tennessee, and other Sites. Quaternary Science Reviews 186: 47-58 (https://doi.org/10.1016/j.quascirev.2018.02.018)
Dillehay, T.D. Bonavia, D., Goodbred, S., Pino, M., Vasquez, V., Rosales Tham, T., Conklin, W., Splitsoser, J., Piperno, D., Iriarte, J., Grobman, A., Levi-Lazzaris, G., Moreira, D., Lopez, M., Tung, T.A., Titelbaum, A., Verano, J., Adovasio, J., Cummings, L., Bearez, P., Dufour, E., Tombret, O., Ramirez, M., Beavins, R., DeSantis, L., Rey, I., Mink, P., Maggard, G., Franco, T. 2012. Chronology, mound-building and environment at Huaca Prieta, coastal Peru, from 13700 to 4000 years ago. Antiquity 86: 48-70 (https://doi.org/10.1017/S0003598X00062451)
See Book Chapters on Publications Page, many of which resulted form collaborations with Archaeologists.
