Journal of Comparative Physiology A

, Volume 199, Issue 12, pp 1093–1104

Evaporative respiratory cooling augments pit organ thermal detection in rattlesnakes

Authors

  • Viviana Cadena
    • Department of Biological SciencesBrock University
  • Denis V. Andrade
    • Departamento de ZoologiaUniversidade Estadual Paulista
    • Instituto Nacional de Ciência e Tecnologia em Fisiologia Comparada
  • Rafael P. Bovo
    • Departamento de ZoologiaUniversidade Estadual Paulista
    • Department of Biological SciencesBrock University
    • Instituto Nacional de Ciência e Tecnologia em Fisiologia Comparada
Original Paper

DOI: 10.1007/s00359-013-0852-4

Cite this article as:
Cadena, V., Andrade, D.V., Bovo, R.P. et al. J Comp Physiol A (2013) 199: 1093. doi:10.1007/s00359-013-0852-4

Abstract

Rattlesnakes use their facial pit organs to sense external thermal fluctuations. A temperature decrease in the heat-sensing membrane of the pit organ has the potential to enhance heat flux between their endothermic prey and the thermal sensors, affect the optimal functioning of thermal sensors in the pit membrane and reduce the formation of thermal “afterimages”, improving thermal detection. We examined the potential for respiratory cooling to improve strike behaviour, capture, and consumption of endothermic prey in the South American rattlesnake, as behavioural indicators of thermal detection. Snakes with a higher degree of rostral cooling were more accurate during the strike, attacking warmer regions of their prey, and relocated and consumed their prey faster. These findings reveal that by cooling their pit organs, rattlesnakes increase their ability to detect endothermic prey; disabling the pit organs caused these differences to disappear. Rattlesnakes also modify the degree of rostral cooling by altering their breathing pattern in response to biologically relevant stimuli, such as a mouse odour. Our findings reveal that low humidity increases their ability to detect endothermic prey, suggesting that habitat and ambush site selection in the wild may be influenced by external humidity levels as well as temperature.

Keywords

ThermosensationPit organThermal imagingRespiratory coolingHeat detection

Copyright information

© Springer-Verlag Berlin Heidelberg 2013