Andrew Altieri
Postdoctoral research associate, Bertness Lab
Ph.D., Email: Andrew Altieri@brown.edu

Emanuel (Manny) Azizi
Ph.D., Organismic and Evolutionary Biology, University of Massachusetts, Amherst, 2005. Thesis title: “ Biomechanics of salamander locomotion.” The primary theme of my research is the form and function of the musculoskeletal system in vertebrates. Specifically I am interested in how the spatial organization (architecture) of muscle fibers determines the mechanical output of muscle-tendon units during locomotion. My work combines geometric modeling, in situ physiological techniques and in vivo measurements during locomotion in order to better understand the functional significance of muscle architecture. By developing a comprehensive understanding of muscle architecture, I aim to integrate the mechanical demands of locomotion with the physiological constraints of the vertebrate sarcomere. My doctoral work was primarily focused on the form and function of segmented axial musculature in fishes and salamanders during swimming. For my post-doctoral work I have been using wild turkeys as a model system for understanding the dynamic behavior of pinnate muscles during running. In addition to my primary research interests, I also have ongoing collaborations focused on the ontogeny of locomotor performance in amphibians, phenotypic plasticity of locomotor structures, and underwater walking in tetrapods.

David Baier

Regina Campbell Malone
Ph.D., Biological Oceanography, 2007
MIT/Woods Hole Oceanographic Institution Joint Program, Cambridge/Woods Hole, MA
Michael J. Moore, advisor Thesis title: Biomechanics of North Atlantic Right Whale Bone: Mandibular Fracture as a Fatal Endpoint for Blunt Vessel-Whale Collision Modeling
B.S., Biological Sciences, 2000, State University of New York at Buffalo, Buffalo, NY

Current Research: I study the biomechanical behavior of bone in an effort to understand the relationship between the form (gross and microscale) and function of bone in various taxa from an evolutionary perspective. I am presently investigating the structure of trabecular and cortical bone in extant marine mammals. My preliminary studies indicate that mandibular bone from the North Atlantic right whale (Eubalaena glacialis) exhibits a cross-sectional density gradient between the trabecular interior and the cortical shell. This is in stark contrast to the abrupt transition between trabecular and cortical bone when viewed in cross-section in terrestrial mammals. I plan to explore the anatomical distribution (beyond the mandible), evolutionary history and the functional/mechanical significance of this novel structure. I will also explore how widespread this structure is taxonomically in order to determine whether it may have adaptive significance for secondarily aquatic mammals. In addition to bone biomechanics, my research interests include cetacean life history, conservation and management, cetacean feeding mechanics and secondary adaptations to aquatic and marine life.

Joaquin Chaves
My current research at Brown University focuses on how hydrological mechanisms and pathways may contribute to the larger set of geologic processes (e.g. uplift, erosion) that affect soil age and the availability of phosphorus in tropical landscapes. A fundamental question in our project is how does soil residence time vary between locations in different erosional environments and how that, in turn, affects soil fertility. We are exploring these questions in two contrasting tropical settings: the Guyana Shield in Venezuela and the Coto Brus Valley in southwestern Costa Rica, which occupy the extremes of erosion and uplift rates, and presumably, soil ages. We hope to contribute to the understanding of factors that affect the nutrient status of tropical forest and how these systems are going to respond to global change.

Thomas Flatt
B.Sc., Biology, University of Basel, 1994
M.Sc., Population Biology, University of Basel, 1999
Ph.D., Evolutionary Biology, University of Fribourg, 2004. Thesis title: "The effects of juvenile hormone on trait architecture in Drosophila melanogaster"
Research: I am interested in the evolution and mechanisms of senescence and the cost of reproduction using Drosophila as a model system
Link to personal website

Pedro Flombaum
B.S. Biology, Universidad de Buenos Aires, 1997
Ph.D. Brown University, 2007 My PhD project was focused on the effects of plant species diversity on ecosystem functioning, for which I conducted some manipulative experiments in the Patagonian steppe, Argentina. I found that primary production was positively associated with the diversity of plant species. In addition, the biodiversity effect in this natural ecosystem was much larger than previously reported for artificial ecosystems. The loss of biodiversity may have larger consequences for the functioning of natural ecosystems than previously thought.

Erica Garcia

Nickolay Hristov

Jennifer Knies

Colin Meiklejohn

Kristi Montooth
Ph.D., Genetics, Cornell, 2005. “An evolutionary genetic analysis of metabolic pathways and physiological performance in Drosophila.” Andy Clark, advisor
Email: Kristi_Montooth@brown.edu.

We now have access to genome sequence as well as maps of the biochemical pathways underlying cellular processes for many organisms. The challenge remains to integrate gene and biochemical network information to identify connections between genetic variation and complex trait variation in natural populations. My interests lie in the population and evolutionary genetics of traits that depend upon energy flow through metabolic pathways. My research employs a candidate pathway approach to investigate the quantitative genetics of flight metabolism and the evolutionary implications of interactions between ethanol, acetic acid and phospholipid metabolism in Drosophila.

In David Rand’s lab I am extending this approach to include flux through the oxidative phosphorylation complexes. Oxidative phosphorylation requires cooperation between mitochondrial and nuclear genomes, both through physical interactions within the complexes and in the coordinated regulation of cytosolic and mitochondrial metabolism. I am currently investigating the physiological consequences of disrupting the co-evolved relationship between mitochondrial and nuclear genomes in Drosophila and the role that diet and naturally-occurring nuclear genetic variants play in mediating this disruption.

Daniel Riskin

Daniel K. Riskin Ph.D., Zoology, Cornell University, 2006. M.Sc., Biology, York University, 2000. B.Sc., Zoology, University of Alberta, 1997. I am interested in the way in which the bodies of different species are shaped by the biomechanical consequences of their divergent life histories. Bats are ideal for this system of study because while all >1,200 species share a body plan that permits flight, there are striking differences among them in almost every other aspect of behaviour and ecology. Previously, I have investigated the influence of morphology on roosting ecology, and on terrestrial locomotion. Since coming to Brown, I have focused on flight, with particular interest in how the body motions (kinematics) of bats differ among species with different body sizes and shapes. My personal website has more information about my research, along with some photos and movies of the bats that I love working with so much (http://www.noctilio.com).

Brian Sage
Ph.D. in Biological Sciences, Carnegie Mellon University, September 2004
e-mail: Brian_Sage@brown.edu
personal web page/CV

Research: I utilize Drosophila and cell culture to study the molecular mechanisms of aging. I am particularly interested in two factors that have been shown to influence aging across a variety of species, dietary restriction and the insulin/insulin-like growth factor signaling pathway. My goal is to further elucidate the genes and pathways that result in these factors' affect on aging.

Gregory Sawicki
Ph.D., Kinesiology and Mechanical Engineering, University of Michigan, Ann-Arbor, 2007. Thesis title: “Mechanics and energetics of walking with powered exoskeletons” My post-doctoral research will focus on the mechanics, energetics and neural control of the muscle-tendon complex. I will use simple mechanical models to explore the role of tendon in shaping the muscle-length trajectory during cyclic contraction. Model predictions will be tested experimentally in (1) the human Achilles tendon-triceps surae complex (using ultrasound) and (2) the bullfrog Achilles tendon-plantaris complex (using direct measurements). My ultimate goal is to establish an academic research program using biological principles to develop better lower-limb robotic devices to assist both healthy and impaired human locomotion.-->Link to Greg's Website

Justin Schaefer

Juliet Simpson

Eugenia Villa-Cuesta

Amity Wilczek: Ph.D. Harvard University, 2004. Thesis title: "The Roles of Life History and Environmental Heterogeneity in the Evolution of Maternal Effects in Plants."
e-mail: Amity_Wilczek@brown.edu
Research: My research interests lie in how plants integrate complex cues and signals into an environmentally appropriate response. For plants that occupy a wide range of habitats, what consitutes an appropriate response to a given environmental cue in one habitat may not be adaptive in another. My current research seeks to elucidate how geographic variation in selection pressures shapes plant response through a combination of phenotypic and genetic analyses. In the Schmitt Lab I am studying geographic variation in natural selection in the annual plant and genetic model system Arabidopsis thaliana, which has established successful populations throughout a wide geographic and climatic range in Europe, Asia and North America. Due to its broad habitat range, different populations of A. thaliana experience wildly different season lengths and growing temperatures. Arabidopsis thaliana shows substantial natural variation in germination timing, date and season of flowering and lifespan, but the exact geographic pattern of these life history traits and their consequences for fitness remain unclear. In collaboration with Arabidopsis laboratories at five field sites in Spain, Germany, England, and Finland (in Europe,) we will test the prediction that variation in climate favors different flowering responses in different regions. At each site and in multiple seasons we will measure fitness of a large set of genetically diverse lines including ecotypes drawn from throughout A. thaliana's range as well as controlled background genotypes harboring alternate alleles of key genes in flowering time pathways. These data will further our understanding of the geographic variation in natural selection on life history across the native range of Arabidopsis thaliana, the relationship between natural genetic variation and local adaptation, and the role that different developmental pathways play in shaping adaptive responses.

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