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Warren Porter

Warren P. Porter

Research|Teaching |Publications| Outreach
Niche Mapper™

207 Zoology Research
Office: (608)262-1719
Lab: (608)262-0029


Molecular and Environmental Toxicology
The Nelson Institute: Conservation Biology and Sustainable Development
Engineering Physics

email Warren           Warren Porter CV pdf  CV

Research Interests

    Goals: To understand

    1. how spatially explicit climate, topography, and vegetation interact with ectotherm and endotherm morphology, physiology and behavior, disease.
    2. how low level contaminant/pesticide mixtures affect potential for survival, growth, reproduction and how that affects population dynamics, community structure and food web structure in time and space.
    3. how low-level contaminant/pesticide mixtures at environmentally relevant concentrations affect/alter developmental processes, neurological function (learning abilities and aggression levels), immune function, and endocrine function.
    4. the process of infection and the biochemical responses to bacterial and viral infections

    This past year has been an exceptional one for our lab in all three areas of our research. 

    • Modeling Animal Landscapes: This has been the most exciting year ever. We documented our ability to design digital 3-D animals, animate them, insert them into computational fluid dynamics, then Niche Mapper™, then quantitatively evaluate on land and/or at sea their energetics, behavior and distribution in the past, present and future at local and global scales. 1) We were able to demonstrate this ability for sea turtles thanks to the excellent collaboration of colleagues Drs. Jeanette Wyneken, T. Todd Jones and Riccardo Bonazza and the remarkable work of my graduate student, Peter Dudley. Collectively we obtained experimental data to validate calculated sea turtle drag and heat transfer, behavior, energetics and distribution limits derived from designing sea turtles in 3-D, animating them, swimming them in virtual reality and computing their drag and heat transfer properties and use that information to compute current and future distributions across the globe as well as suitable nesting sites currently and in the future. We were awarded entry into the ANSYS Hall of Fame for this achievement using leatherbacks. Only one other academic research group in the world also entered that Hall of Fame this year. 2) We have also published a paper documenting our ability to reconstruct microclimates across the globe above and below ground typically within 1°C and as a worst-case approximately 2.5° C as compared to on-site measurements in Australia, Europe and North America.

      Our recent work with leatherback sea turtles establishes our globally unique capacity to create animated virtual 3-D fossil or living animals of any geometry from initial creation to landscape scale energetics, behavior and distribution limits. Our new collaborative paper on tracking hatchling loggerhead sea turtles in the Atlantic and how their ‘riding’ sargassum gives them ‘hot’ islands in the ocean for faster growth and development was covered by BBC, Science news and Scientific American, among others. Our collaborative work contributing to the discovery of koalas hugging trees to stay cool was also covered by multiple global news agencies. Our Niche Mapper model made it possible to prove what they were doing was cooling them and how much it helped them.

    • Subtle Biological Effects of Environmental Contaminants: In collaboration with Dr. Fariba Assadi-Porter, the lead person in this research, we have a paper in Obesity that uses NMR and our breath biomarker technology to identify metabolic changes induced by a thyroid hormone related molecule that increases fat burning and induces weight loss in the absence of changes in food consumption.
    • Early detection of infectious or chronic diseases: We have a new paper describing the first clinical trial at UW Hospitals for early infection detection. It shows that our early detection of infection technology works in humans in a clinical setting. I am a founder and board member of an off-campus company, Isomark, LLC, that has licensed our early detection technology. Two other papers, again led by Dr. Assadi-Porter, use stable isotopes in breath to show PCOS women can’t oxidize lipids and the other confirms that we can use our technology to identify changes in energy balance and substrate utilization in real time. There are more than 3500 citations to our work according to the ISI Web of Knowledge.



    Zoology 504:  Modeling Animal Landscapes
    Zoology 486: New methods in Environmental Toxicology
    Zoology 956: Seminar - Ecology

    Note to prospective graduate students:

    I look for high intelligence, independence, creativity, and imagination in my students. I also look for broad interests, someone who likes personal challenges, and a synthetic capacity.
    Opportunities in my lab are largely limited by time and the student's capacity to learn.  We do interdisciplinary research and collaborate with faculty in engineering sciences, global climate and vegetation modeling, medical and veterinary sciences, and the physical sciences.

    Graduate students currently supervised:

    • Stephanie Buxel-Florenzen - white nose syndrome and energetics in bats.
    • Megan Fitzpatrick, - Predicting Potential Habitat of the Endangered Whooping Crane (Grus americana) through Mechanistic Modeling.
    • Paul Mathewson – Mechanistic calculations of the energetics, behavior and habitat utilization of polar bears in modern and future climate scenarios.
    • Javier Velasco - Toxicity of plasticizers, PAH’s and other toxicants due to plastic ingestion in Leatherback Sea Turtles.**

    Students supervised who've recently earned graduate degrees:

    Julia Haviland -Impact of common low-level environmental contaminants on neurological, endocrine, immune, DNA methylation, metabolome phase portrait shifts and developmental processes in mice.

    Lucas Moyer-Horner - Present and past landscape ecology, energetics, behavior and distribution limits of yellow bellied marmots and pikas in western United States.

    Sue Vang, M.S. 2008  

    Mark Jankowski, Ph.D. 2007
    Environmental toxicology, immune suppression and infectious disease. 

    Joe Meisel, Ph.D. 2004
        How habitat fragmentation interacts with climate to affect distribution of insects and their avian predators in the tropics of Central America.

    Auston M. Kilpatrick, Ph.D.
        Aspects of community ecology, including: mechanisms generating patterns of mammalian diversity, spatial and temporal variation in competitive interactions, and the coevolution of avian malaria and native and introduced Hawaiian birds. (Abstract)

    Maria Fernanda Cavieres Fernandez, Ph.D.
        Reproductive and developmental toxicity of a commercial herbicide formulation in mice, (Abstract)

    Christopher R. Tracy, PhD
        Pattern and theory of geographic variation in physiology and body size in Sauromalus obesus. (Abstract)

    Elizabeth Sutherland, MS
        Dispersion of Timber wolves in north central Wisconsin

Selected Publications

Niche Mapper™

Niche Mapper™ is a patented collection of three mechanistic models that include a broadly applicable microclimate, ectotherm and endotherm model of heat and mass transfer and animal behavior. The microclimate model allows the translation of coarse spatial data, such as digital elevation models (DEMs), vegetation data, weather station data and spatially interpolated climate records, into microclimatic environmental variables relevant to the thermal and hydric ecology of organisms. These variables include air temperature, humidity and wind speed gradients above ground, soil thermal profiles and solar and thermal infrared radiation environments.

The ectotherm and endotherm models can use the output of the microclimate model, or user-collected data, to solve energy and mass balances for organisms contingent on the morphological, physiological and behavioral traits entered by the user. /Mass and heat balances are coupled, i.e. the heat balance specifies the mass flows that must occur through the gut and the respiratory system to sustain calculated metabolic/water loss rates that are dependent on the animal and local environmental properties./ The basic outputs include body temperature, metabolic rate and water loss rate in hourly time steps. These can be translated into functions of activity, dispersal, survival, growth and reproduction potential, landscape utilization patterns and distribution limits, as well as selection strengths in the context of spatial evolutionary studies.

The ectotherm model can also be used to simulate inanimate objects, such as ponds or water containers if the user chooses. Steady-state and transient (large thermal mass) scenarios can be run, and behavioral code is available for a range of organism behaviors (e.g. fossorial, arboreal, terrestrial, flying, diving, hibernating), although some ‘tweaking’ of the behavioral subroutines may be necessary for your organism. /The user may choose from an assortment of default geometries or may define their own set of geometries for the head, neck, torso, front legs and back legs.

The programs are Fortran executables. When used for landscape scale calculations, rather than point simulations, /there is a Perl program to communicate with MySQL databases for input and output and to call the Fortran executables. There is a set of user Niche Mapper™ instructions that is available as well as instructions for the use of MySQL to set up the databases and for Perl to interface the databases and the Fortran executable codes.

This site is under construction and we are working on developing more user friendly interfaces and a detailed manual. At this stage, please contact me via email for information about, and access to, the programs.

Businesses founded: potential conflicts of interest.

Dr. Porter is a co-founder and advisory committee member of Isomark, LLC. The company is currently in clinical trials using stable isotopes in breath to determine onset of infection non-invasively much earlier than other currently available technologies. Dr. Porter is a co-founder of Niche Mapper, LLC. The company is in beta testing of dairynichemapper, a GUI interface that is a decision support tool for dairy producers to optimize cow and environmental properties to maximize milk production and minimize production costs. It utilizes a modified version of the broadly tested generic Niche Mapper model for wild animals.


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