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Goldstein, Bob

December 14, 2023

We are interested in understanding how cells develop into organisms. We love the nematode C. elegans, because it allows us to readily combine a great number of useful techniques, including techniques of cell biology, direct manipulation of cells, forward and reverse genetics, biochemistry, molecular biology, biophysics, and live imaging of cells and their dynamic, cytoskeletal components. Current work in the lab addresses several fundamental questions in cell and developmental biology — how cells move to specific positions during development, how cells change shape, how developmental patterning mechanisms tell cell biological mechanisms what to do where and when, how intercellular signals act to polarize cells, and how the mitotic spindle is positioned in cells.

We have also been developing a relative of C. elegans and Drosophila, a water bear (tardigrade), to study how developmental mechanisms can evolve to produce organisms with different forms and how biological materials can survive unusual extremes.

C. elegans and tardigrades

Riddell, Eric

August 17, 2023

Our lab uses physiology to understand how animals respond to environmental change. Our research blends experimental biology with simulation-based computer models to identify the physiological processes driving species’ distributions, extinction, and adaptation. The approach requires insight from behavior, physiology, and physics, providing an integrative perspective into organismal biology. Through the synthesis of these disciplines, we provide a comprehensive understanding of organisms, from genes to geographic ranges, while improving our capacity to predict the impact of climate change.

Johri, Parul

January 19, 2023

The Johri Lab is interested in how evolutionary processes like changes in population size, recombination rate, direct and indirect effects of selection and factors such as genome architecture shape patterns of genomic variation. Work in the lab involves employing computational and theoretical approaches or statistical method development or using an empirical approach to perform evolutionary inference and ask fundamental questions in population genetics. Here are some questions that we are interested in:

  • How much do adaptive vs. non-adaptive evolutionary processes contribute to genome-wide patterns of variation?
  • How does selection shape patterns of variation at nearby linked sites?
  • What does the distribution of fitness effects of new mutations look like across species? How can we infer its shape from population-genetic data?
  • What are the selective forces acting on other types of mutations like gene duplicates?
  • Publications

    Weakley, Alan S.

    September 6, 2011

    I am a plant systematist, plant community ecologist, biogeographer, and conservation biologist focused on the species and systems of the Southeastern United States.  Students in my lab focus on the systematics and biogeography of the Southeastern United States, community classification developing the U.S. National Vegetation Classification, and land management, conservation planning, and environmental policy questions involving the conservation of Southeastern United States ecosystems and species. Prior to coming to UNC in 2002, I had an extensive career in applied conservation biology, working with the North Carolina Natural Heritage Program, The Nature Conservancy, and NatureServe (the Association for Biodiversity Information).  My conservation interests and activities continue, with my service as Trustee of the N.C. Natural Heritage Trust Fund ( from 2008-2013 (which has provided $328 million through 518 grants to support the conservation of more than 298,000 acres of natural areas in North Carolina), Chair of the N.C. Plant Conservation Program’s Scientific Advisory Committee (, and Chair of the N.C. Natural Heritage Program Advisory Committee ( I am the author of Flora of the Southern & Mid-Atlantic States (, a taxonomic manual covering about 7000 vascular plant taxa, now the standard in use across much of the Southeastern United States.  With J. Chris Ludwig and Johnny Townsend, I am co-author of the Flora of Virginia (, published in 2012 and awarded the Thomas Jefferson Award for Conservation, and am also an active author, editor, reviewer, and director of the Flora of North America project (  I was a co-founder of the Carolina Vegetation Survey (, and continue as one of its four organizers.

    Hurlbert, Allen

    July 14, 2011

    In the Hurlbert Lab we ask questions about the structure of ecological communities, and the processes that are responsible for determining the patterns of diversity, composition, turnover and relative abundance both within local assemblages and across the globe. Our work spans vertebrate, invertebrate, and plant communities, and we use a variety of approaches from manipulative experiments to modeling to working with global scale datasets. Current projects in the lab use

    “Ecological patterns, about which we construct theories, are only interesting if they are repeated. They may be repeated in space or in time, and they may be repeated from species to species. A pattern which has all of these kinds of repetition is of special interest because of its generality, and yet these very general events are only seen by ecologists with rather blurred vision. The very sharp-sighted always find discrepancies and are able to say that there is no generality, only a spectrum of special cases. This diversity of outlook has proved useful in every science, but it is nowhere more marked than in ecology.”

    –Robert MacArthur, 1968

    Hedrick, Tyson L.

    June 14, 2011

    How do animals produce and control movement? How does a network of muscles, rigid elements and neurons – components of varying quality and with temporally varying responses – generate robust outputs in the face of uncertain circumstances? For example, the flight of the sphingid moth Manduca sexta is enabled by a complex, hierarchical biological system that involves processes and components at several different levels: the nervous system of the moth activates a suite of 20 flight muscles which actuate mechanical structures (the wings) that do work on the surrounding fluid (air), generating forces to support and propel the moth. These forces lead to changes in position and orientation which are detected by the sensory system and then used, along with underlying feedforward patterns as the basis for future muscle activation patterns, continuing the process and keeping the moth in the air.

    Specific Areas of Research:

    • Aerodynamics of bird and insect flight
    • Neuromuscular and sensory control in animal flight
    • Computational approaches to organismal biomechanics

    I apply both experimental and computational modeling approaches to these questions, iterating between the two approaches. For example, the figure below shows the wingbeat to wingbeat variation in wing motion during stable hovering flight for both a real moth and a computational model of the moth. In both the model and organism, steady flight behaviour requires continuous slight adjustments.

    In addition to investigating the underlying variation of steady locomotion, I also make direct measurements from animals engaged in maneuvering or other unsteady movements. Figure 2 (below) outlines the basis of roll damping in the flapping flight of birds. Surprisingly high roll damping coefficients allow birds to control roll orientation with simple changes in wingbeat amplitude and passively dissipate roll velocity once symmetric flapping resumes.

    Pfennig, Karin

    June 14, 2011

    At a Glance

    Environment-dependent behavior, hybridization, mating behavior evolution, sexual selection, speciation and species distributions.



    The overarching goal of my research is to understand how behavior drives the origins and distribution of biodiversity. Because mate choice is a potent selective force that can be critical in the formation of novel phenotypes and new species, I focus on the evolution of mating behavior and its role in ecological and evolutionary processes. I work with natural populations and use a variety of approaches ranging from behavioral experiments to genetic analyses. For more details, including references, please go to my lab website.

    Pfennig, David W.

    June 14, 2011

    I’m broadly interested in the interplay among evolution, ecology, and development.  My current research focuses on three main topics.

    First, I study the causes and consequences of a common feature of development: its tendency to be responsive to changes in the environment.  Although biologists have long known that an individual organism’s appearance, behavior, and physiology can be modified by its environmental conditions, the implications of such developmental (or phenotypic) plasticity for ecology and evolution remain poorly understood. Moreover, the underlying genetic and developmental mechanisms that foster plasticity’s evolution are unclear.  I seek to understand the impacts of plasticity on diversification and evolutionary innovation, as well as how and why plasticity arises in the first place.

    Second, I study the role of competition in generating and maintaining biodiversity.  I’m particularly interested in unravelling whether and how competition promotes trait evolution and the impacts of any such evolution on the formation of new traits and new species.

    Finally, I study a striking form of convergent evolution known as Batesian mimicry, which evolves when a palatable species co-opts a warning signal from a dangerous species and thereby deceives its potential predators. Such instances of “life imitating life” provide an ideal opportunity to assess natural selection’s efficacy in promoting adaptation.

    For more details on my lab and research, please visit my lab page by clicking on the link above.

    Kier, William M.

    June 14, 2011

    William M. Kier is interested in the comparative biomechanics of marine invertebrates. He is especially interested in the functional morphology of musculoskeletal systems, in the structure, function, development and evolution of muscle, and in invertebrate zoology, with particular emphasis on the biology of cephalopod molluscs (octopus and squid). His research is conducted at a variety of levels and integrates the range from the behavior of the entire animal to the ultrastructure and biochemistry of its tissues. A variety of techniques are used including normal and high-speed video, histological and histochemical methods, light and transmission electron microscopy, electromyography, muscle mechanics, biochemistry and molecular techniques. His research concerns the role of the musculature of cephalopods (squid, octopus, nautilus) in both creating movement and providing skeletal support. The principles derived from this analysis have been applied to other structures such as the tongues of mammals and lizards and the trunk of the elephant. More recently, these insights have been used in collaboration with engineers and biologists in the design and construction of novel robotic mechanisms. He is also investigating the mechanisms of the evolution of muscle specialization, especially the evolution of fast contraction in the muscle of cephalopods. Please visit the Kier Lab home page for more information on these topics.

    Prospective Graduate Students: Applications for graduate study should be submitted directly to the Department of Biology, rather than to the Biological and Biomedical Sciences Program (BBSP). Information on applying to the Department of Biology graduate program in Evolution, Ecology and Organismal Biology is available here.

    Photograph of histological cross-section of the tentacle of Loligo pealei.
    Photograph of newly molted blue crab, Callinectes sapidus. Dr. Jennifer Taylor, a recent Ph.D. student in the Kier lab, showed that many crustaceans switch to a hydrostatic skeleton immediately following shedding of the rigid skeleton. For more information please visit the Kier Lab home.