How melanism affects the sensitivity of lizards to climate change

Sebastian Mader, Jonathan Goldenberg, Federico Massetti, Karen Bisschop, Liliana D’Alba, Rampal S. Etienne, Susana Clusella-Trullas, Matthew D. Shawkey

Research output: Contribution to journalArticlepeer-review

Abstract

The impact of climate change on global biodiversity is firmly established, but the differential effect of climate change on populations within the same species is rarely considered. In ectotherms, melanism (i.e. darker integument due to heavier deposition of melanin) can significantly influence thermoregulation, as dark individuals generally heat more and faster than bright ones. Therefore, darker ectotherms might be more susceptible to climate change. Using the colour-polyphenic lizard Karusasaurus polyzonus (Squamata: Cordylidae), we hypothesized that, under future climatic projections, darker populations will decrease their activity time more than brighter ones due to their greater potential for overheating. To test this, we mechanistically modelled the body temperatures of 56 individuals from five differently coloured populations under present and future climate conditions. We first measured morphological traits and integumentary reflectance from live animals, and then collected physiological data from the literature. We used a biophysical model to compute activity time of individual lizards as proxy for their viability, and thereby predict how different populations will cope with future climate conditions. Contrary to our expectations, we found that all populations will increase activity time and, specifically, that darker populations will become relatively more active than bright ones. This suggests that darker populations of K. polyzonus may benefit from global warming. Our study emphasizes the importance of accounting for variation between populations when studying responses to climate change, as we must consider these variations to develop efficient and specific conservation strategies. A free Plain Language Summary can be found within the Supporting Information of this article.

Original languageEnglish
Pages (from-to)812-825
JournalFunctional Ecology
Volume36
Issue number4
DOIs
Publication statusPublished - 2022 Apr
Externally publishedYes

Bibliographical note

Funding Information:
S.M. was aided by the Marco-Polo Grant of the University of Groningen. J.G. was funded by the Special Research Fund of Ghent University (BOF), supported by the Platform for Education and Talent (Gustave Boël-Sofina Fellowship) and by the King Leopold III Fund for Nature Exploration and Conservation. F.M. was funded through the Stellenbosch University's Botany & Zoology Department Scholarship for international students. K.B. was supported by the NWA-ORC Project 400.17.606/4175. This work was supported by the Research Foundation-Flanders (FWO) grant GOG2217N, FWO/South Africa NRF Research Cooperation grant-FLGR160625174165 and AFOSR FA9550-18-1-0477. This project significantly benefited by the help in the field of Sarah de Gruchy, Ashley Koopman, Cécile Vansteenberghe, Matthew Brandon Arendse and Tristan de Vos. The authors especially thank Karla Alujević and Svana Rogalla for helping to set up the project. They are deeply grateful to Marius Burger, Michael Bates and Chad Kates for providing field site information. They extend their gratitude to all farmers and landowners who granted them access to their lands and helped them with collection (for poaching issues, we are omitting those names). They thank Michael Kearney and Diederik Strubbe for constructive discussions.

Funding Information:
S.M. was aided by the Marco‐Polo Grant of the University of Groningen. J.G. was funded by the Special Research Fund of Ghent University (BOF), supported by the Platform for Education and Talent (Gustave Boël‐Sofina Fellowship) and by the King Leopold III Fund for Nature Exploration and Conservation. F.M. was funded through the Stellenbosch University's Botany & Zoology Department Scholarship for international students. K.B. was supported by the NWA‐ORC Project 400.17.606/4175. This work was supported by the Research Foundation‐Flanders (FWO) grant GOG2217N, FWO/South Africa NRF Research Cooperation grant‐FLGR160625174165 and AFOSR FA9550‐18‐1‐0477.

Publisher Copyright:
© 2021 The Authors. Functional Ecology published by John Wiley & Sons Ltd on behalf of British Ecological Society.

Free keywords

  • global warming; activity time
  • integument absorptivity
  • Karoo Girdled lizard
  • mechanistic model
  • niche model

Fingerprint

Dive into the research topics of 'How melanism affects the sensitivity of lizards to climate change'. Together they form a unique fingerprint.

Cite this