Rapid Changes in Coloration in Adult Field Crickets in Response to Climate Change
Poster Number
60
Faculty Mentor Name
Zach Stahlschmidt
Research or Creativity Area
Natural Sciences
Abstract
The animal kingdom displays a diverse array of colors. The ability to express different types of melanin-based coloration may be crucial for animals’ adaptation to climate change. For example, insects can adopt lighter coloration to limit heat absorption from solar radiation (‘thermal melanism hypothesis’). Other environmental factors, such as water availability and predation risk, may also affect melanism or dark coloration. Cuticular melanin plays a role in many adaptive responses in insects, such as reducing water permeability, so darker insects can exhibit reduced rates of water loss during drought (‘water conservation hypothesis’). Insects also rely on crypsis or camouflage to reduce predation risk, with dark environments potentially increasing melanization and light environments reducing it (‘crypsis hypothesis’). Here, we used a factorial design to manipulate temperature (20℃ or 30℃), water availability (with or without drinking water), and environmental color (white or black background) during early adulthood in the variable field cricket (Gryllus lineaticeps), which naturally exhibits a range of coloration, from pale tan to red to black. We measured melanization in the crickets' wing pads to test the relative importance of temperature, water availability, and crypsis in the plasticity of coloration, as well as potential interactive effects between these factors. Preliminary results indicate strong support for the thermal melanism hypothesis, no support for the crypsis hypothesis, and contradictory support for the water conservation hypothesis. Our research will clarify how plasticity in coloration may respond to ongoing climate change and urbanization, which continue to alter temperature, water availability, and predation risk worldwide.
Location
University of the Pacific, DeRosa University Center
Start Date
26-4-2025 10:00 AM
End Date
26-4-2025 1:00 PM
Rapid Changes in Coloration in Adult Field Crickets in Response to Climate Change
University of the Pacific, DeRosa University Center
The animal kingdom displays a diverse array of colors. The ability to express different types of melanin-based coloration may be crucial for animals’ adaptation to climate change. For example, insects can adopt lighter coloration to limit heat absorption from solar radiation (‘thermal melanism hypothesis’). Other environmental factors, such as water availability and predation risk, may also affect melanism or dark coloration. Cuticular melanin plays a role in many adaptive responses in insects, such as reducing water permeability, so darker insects can exhibit reduced rates of water loss during drought (‘water conservation hypothesis’). Insects also rely on crypsis or camouflage to reduce predation risk, with dark environments potentially increasing melanization and light environments reducing it (‘crypsis hypothesis’). Here, we used a factorial design to manipulate temperature (20℃ or 30℃), water availability (with or without drinking water), and environmental color (white or black background) during early adulthood in the variable field cricket (Gryllus lineaticeps), which naturally exhibits a range of coloration, from pale tan to red to black. We measured melanization in the crickets' wing pads to test the relative importance of temperature, water availability, and crypsis in the plasticity of coloration, as well as potential interactive effects between these factors. Preliminary results indicate strong support for the thermal melanism hypothesis, no support for the crypsis hypothesis, and contradictory support for the water conservation hypothesis. Our research will clarify how plasticity in coloration may respond to ongoing climate change and urbanization, which continue to alter temperature, water availability, and predation risk worldwide.
