1/35
  • Home

  • Group photo

  • Registration and Costs

  • Abstract Submission

  • Geronimo Event Center

  • Schedule

  • More

    The Costs of Being Cool: Panting Thresholds, Thermal Limits, and Evaporative Cooling In Southwestern Lizard Communities

    Loughran, Caleb L.

    Wolf, Blair O.

     

    University of New Mexico

    Department of Biology

    University of New Mexico

    Albuquerque, NM USA

    loughran@unm.edu

     

    In the American Southwest, operative environmental temperatures (Te) often exceed what is physiologically tenable for many reptilian species. When faced with extreme environmental temperatures, lizards must either retreat to thermal refugia or attempt to maintain or lower body temperature (Tb) through evaporative processes such as open-mouth panting. Currently, the capacities for evaporative heat dissipation are largely unknown as are the relative efficiencies of evaporative cooling for various species. To better understand the role of panting in body temperature defense against extreme environmental temperatures, we measured thermoregulatory performance for a variety of lizard species native to the southwest. We used flow-through respirometry to gather data on standard metabolic rate (SMR) and evaporative water loss (EWL) at air temperatures (Ta) that ranged from 35°C to 50°C. Concurrently, we used a live-streaming camera to monitor lizard activity, and panting initiation, and Tb in real-time using thermocouples that were inserted into the lizard’s cloaca. We found SMR and EWL, increased steeply following the onset of panting, with the ability to maintain a gradient between Ta and Tb strongly associated with EWL rate. Species inhabiting hot desert environments had higher panting thresholds, were much more efficient at dissipating heat, and tolerated higher Ta’s and Tb’s for longer periods than species adapted to more mesic environments. Identifying the onset of panting, the capacity for heat defense and its relationship to critical thermal limits should provide valuable insight into how climate warming may impact lizard activity and hence water and energy budgets under future climates.

    Please reload

    Accepted Abstracts

     

     

     

    Urban Ecology of Desert Spiny Lizards

    Higher Temperature Tolerance in Ectotherms Facing Threats from an Invasive Predator

    Major Features of Lizard Evolution

    Limb Development of a Limbless Skink

    Embryonic Development of the Musculo-skeletal System of the Madagascar Ground Gecko Paroedura pictus

    Thermal Ecophysiology and Vulnerability to Global Climate Change in a Population of Phrynosoma sherbrookei from Guerrero, Mexico

    Distribution of the Gila Monster in Southwestern New Mexico

    Reproductive Phenology, Distribution and Climate Change in Viviparous Phrynosoma: Implications for the Future Thermal Refugia

    Life in the Thornscrub: Movement, Home Range, and Territoriality of the Reticulate Collared Lizard

    Home Range and Habitat Associations of the Spot-Tailed Earless Lizard

    Please reload

    Contact Us or ask a Question

    Copyright 2018, Biology of Lizards, all rights reserved 
    email smithcf@wofford.edu  for usage information 
    Logo design, Website design, and content: Chuck Smith 
    Website development:
    Chuck Smith

    photo credits: Will Wells and Jack Goldfarb

    ​

    Completed registration forms: admins only