Tara Smiley

Indiana University Bloomington | IUB · Environmental Resilience Institute & Dept of Earth and Atmospheric Sciences

Stable carbon, nitrogen, hydrogen, and oxygen isotopes have been used to infer aspects of species ecology and environment in both modern ecosystems and the fossil record. Compared to large mammals, stable isotopic studies of small-mammal ecology are limited; however, high species and ecological diversity within small mammals presents several advant...

Topographically complex regions on land and in the oceans feature hotspots of biodiversity that reflect geological influences on ecological and evolutionary processes. Over geologic time, topographic diversity gradients wax and wane over millions of years, tracking tectonic or climatic history. Topographic diversity gradients from the present day a...

For mammals today, mountains are diverse ecosystems globally, yet the strong relationship between species richness and topographic complexity is not a persistent feature of the fossil record. Based on fossil-occurrence data, diversity and diversification rates in the intermontane western North America varied through time, increasing significantly d...

We investigate geographic patterns across taxonomic, ecological and phylogenetic diversity to test for spatial (in)congruency and identify aggregate diversity hotspots in relationship to present land use and future climate. Simulating extinctions of imperilled species, we demonstrate where losses across diversity dimensions and geography are predic...

We investigate how oxygen isotopes in equid teeth can be used as a record of seasonality. First, we use in situ laser ablation and conventional microsampling techniques to understand time-averaging of environmental signals in intra-tooth isotope profiles in modern feral horse teeth (n = 5) from Mongolia, where there is a large seasonal gradient in...

American robins and dark-eyed juncos migrate across North America and have been found to be competent hosts for some bacterial and viral pathogens, but their contributions to arthropod-borne diseases more broadly remain poorly characterized. Here, we sampled robins and juncos in multiple sites across North America for arthropod-borne bacterial path...

The Cenozoic landscape evolution in southwestern North America is ascribed to crustal isostasy, dynamic topography, or lithosphere tectonics, but their relative contributions remain controversial. Here we reconstruct landscape history since the late Eocene by investigating the interplay between mantle convection, lithosphere dynamics, climate, and...

American robins and dark-eyed juncos migrate across North America, but their contributions to arthropod-borne disease remain poorly characterized. We identified novel Rickettsia spp. in one wintering migrant per bird species related to bellii, transitional, and spotted fever group rickettsiae and suggest spring migration could disperse these pathog...

As society confronts a multitude of wicked problems without clear solutions, transdisciplinary research institutes have the opportunity to meet the increasingly important challenge to foster research capable of addressing such problems — that is, cross-disciplinary and societally relevant research. There is a growing body of literature on how to co...

Simulations are playing an increasingly important role in paleobiology. When designing a simulation study, many decisions have to be made and common challenges will be encountered along the way. Here, we outline seven rules for executing a good simulation study. We cover topics including the choice of study question, the empirical data used as a ba...

Billions of animals migrate annually in pursuit of food, safety, and reproduction. Long-distance migration can be energetically expensive, which can force tradeoffs with investment in other physiological systems (e.g., suppressing immunity). Understanding the physiological impacts of migration is important to predict when and where such animals may...

More than half of present‐day continental mammals occur in montane regions. This concentration of diversity in regions of high topographic complexity compared to adjacent lowlands and plains constitutes the topographic diversity gradient, one of the major biogeographic patterns across continents today. Several biogeographic processes have shaped th...

Major changes to landscapes, climate, and mammalian faunas occurred at the regional scale in western North America during the Miocene Climatic Optimum (MCO) between ∼17 and 14Ma, but few studies have looked at how the MCO affected basin-scale environments. Paleoenvironmental reconstructions coupled with mammalian fossil assemblages from the Crowder...

Paleoecology investigates the ecology of extinct organisms in relation to their environments and community assemblages. Major aims of paleoecology include the documentation of taxonomic occurrences and abundances across time and space and the reconstruction of species- to community-level ecological traits. Although methodologically similar to the t...

The middle Miocene from 17 to 14 Ma was a time of elevated mammalian diversity in western North America that coincided with the regional development of topographic complexity and the last global warming interval of the Neogene. Understanding the evolutionary and ecological processes that govern past diversity trends and contribute to modern diversi...

The middle Miocene from 17 to 14 Ma was a time of elevated mammalian diversity in western North America that coincided with regional tectonic extension, the development of topographic complexity, and the last major warming interval of the Neogene, the Miocene Climatic Optimum (MCO). Multiple processes govern species richness from local to regional...

The alternating mountain ranges and desert basins of the Great Basin in the western United States support higher species diversity of mammals than any other region of comparable area in temperate North America. Topographically complex regions have strong environmental gradients and heterogeneous habitats that result in fragmented geographic ranges...

The Eocene-Oligocene Lyre, Quimper, and Marrowstone formations on the northeast Olympic Peninsula of Washington are an important sedimentary sequence whose age has long been controversial. They were thought to span the Eocene-Oligocene transition. In addition, previous paleomagnetic studies on the underlying volcanic rocks produced a counterclockwi...