Liliana M. Dávalos is Professor of Conservation Biology at Stony Brook University’s Department of Ecology and Evolution. Her research interests include molecular evolution, phylogenetics and tropical biology. She leads the Tropical Biology group, which studies extinction and survival in deep time, functional genetics in non-model mammals, and deforestation.
Interests
Molecular Evolution
Phylogenetics
Conservation Biology
Education
PhD in Ecology, Evolution,and Environmental Biology, 2004
Columbia University (New York, New York)
Certificate in Environmental Policy Studies, 2001
Columbia University (New York, New York)
BSc in Biology (emphasis on Genetics), 1997
Universidad del Valle (Cali, Colombia)
Experience
Professor Stony Brook University
May 2008 - Present · New York
Responsibilities include:
Project leadership
Course design, instruction & assessment
Service
Lecturer Open University
January 2007 - May 2008 · Milton Keynes
To answer the question of how the shrew shrinks and then regrows its brain, we will establish this unusual species as a new model, by studying the biological, molecular, biochemical and genetic processes behind this reversible size change.
Does not admit new students. We propose to develop a cross-scale research program that focuses on the relationships between phylogenetic diversity, genetic diversity and functional diversity of a biologically and economically important taxonomic group; bees. Switched to bats, summer of 2019.
Does not admit new students. We assembled a group of socio-environmental scientists to analyze and model the natural and human factors that determine the extinction and resilience of insular vertebrate fauna and leverage this understanding into metrics for use in conservation assessments.
Data available to new students. This project focuses on pairs of closely related bat species that sharply differ in their longevity. Detailed genome comparisons between closely related species with different life spans will test different theories of aging
This new training program responds to this challenge with an interdisciplinary set of new courses and a suite of activities united by the theme of “Scientific Training and Research to Inform DEcisions” (STRIDE).
Data available to new students. The project focuses on a relatively unexplored yet crucial aspect of plant-animal mutualisms; volatile chemical communication between plants and vertebrate frugivores.
Data available to new students. This project focuses on a diverse group of tropical bats in which various species evolved acute, specialized hearing, supersensitive eyes, the ability to smell subtle plant chemicals, or highly developed vomeronasal systems (thought to contribute to mating and social hierarchy).
Does not admit new students. The goal of this project was to discover the mechanisms underlying the survival of remnant populations in the WNS-affected area.
Does not admit new students. Noctilionoid bats comprise more than 200 species that span the entire ecological diversity of land mammals. They range from tiny insectivores and nectarivores to large carnivores, and even vampire bats. This is an unparalleled system for understanding how, when, and where bats evolved new diets, changed roosting habits and developed different kinds of echolocation. Together with the N. B. Simmons Lab, we are generating species-level phylogenies using molecular and morphological data, and including fossils of >20 extinct species. These phylogenies provide frameworks for investigating patterns and processes of ecological adaptation, speciation, and extinction across a hyperdiverse group of mammals.
Within‐clade allometric relationships represent standard laws of scaling between energy and size, and their outliers provide new avenues for physiological and ecological research. According to the metabolic level boundaries hypothesis, metabolic rates as a function of mass are expected to scale closer to 0.67 when driven by surface‐related processes (e.g., heat or water flux), while volume‐related processes (e.g., activity) generate slopes closer to one. In birds, daily energy expenditure (DEE) scales with body mass (M) in the relationship log (DEE) = 2.35 + 0.68 * log (M), consistent with surface‐level processes driving the relationship. However, taxon‐specific patterns differ from the scaling slope of all birds. Hummingbirds have the highest mass‐specific metabolic rates among all vertebrates. Previous studies on a few hummingbird species, without accounting for the phylogeny, estimated that the DEE‐body mass relationship for hummingbirds was log (DEE) = 1.72 + 1.21 * log (M). Contrary to theoretical expectations, this slope greater than 1 indicates that larger hummingbirds are less metabolically efficient than smaller hummingbirds. We collected DEE and mass data for 12 hummingbird species, which, combined with published data, represented 17 hummingbird species in eight of nine hummingbird clades over a six‐fold size range of body size (2.7 ‐ 17.5 g). After accounting for phylogenetic relatedness, we found daily energy expenditure scales with body mass as log (DEE) = 2.04 + 0.95 * log (M). This slope of 0.95 is lower than previously estimated for hummingbirds, but much higher than the slope for all birds (0.68). The high slopes of torpor, hovering and flight potentially explain the high interspecific DEE slope for hummingbirds compared to other endotherms.
Gene duplication is a key source of evolutionary innovation, and multigene families evolve in a birth-death process, continuously duplicating and pseudogenizing through time. To empirically test hypotheses about adaptive expansion and contraction of multigene families across species, models infer gene gain and loss in light of speciation events and these inferred gene family expansions may lead to interpretations of adaptations in particular lineages. While the relative abundance of a gene subfamily in the subgenome may reflect its functional importance, tests based on this expectation can be confounded by the complex relationship between the birth-death process of gene subfamily evolution and the species phylogeny. Using simulations, we confirmed tree heterogeneity as a confounding factor in inferring multi-gene adaptation, causing spurious associations between shifts in birth-death rate and lineages with higher branching rates. We then used the olfactory receptor (OR) repertoire, the largest gene family in the mammalian genome, of different bat species with divergent diets to test whether expansions in olfactory receptors are associated with shifts to frugivorous diets. After accounting for tree heterogeneity, we robustly inferred that certain OR subfamilies exhibited expansions associated with dietary shifts to frugivory. Taken together, these results suggest ecological correlates of individual OR gene subfamilies can be identified, setting the stage for detailed inquiry into within-subfamily functional differences.
