Experimental support for the cost-benefit model of lizard thermoregulation

Gabor Herczeg, Abigel Gonda, Jarmo Saarikivi, Juha Merilä

Research output: Contribution to journalArticleScientificpeer-review


According to Huey and Slatkin's [Q Rev Biol 51:363-384, 1976] cost-benefit model of behavioural thermoregulation, lizards should adjust their thermoregulatory strategy between active thermoregulation and thermoconformity (no thermoregulation) according to the costs (time and energy spent thermoregulating, exposure to predators), benefits (optimised physiological performance) and thermal quality of environment associated with a given situation. However, Gilchrist's [Am Nat 146:252-270, 1995] model of thermal specialisation suggests that apparently costly mechanisms of behavioural thermoregulation can greatly increase fitness if the optimal body temperature is achieved. Field studies of ectotherm thermoregulatory strategies under extreme cold conditions and experiments testing the effects of cool environments on thermoregulatory behaviour are surprisingly scarce. We conducted laboratory experiments to test if common lizards Zootoca vivipara (an active thermoregulator in the field) are able to switch between active thermoregulation and thermoconformity in response to different thermal environments. We found that lizards in treatments with an opportunity to reach their preferred body temperature thermoregulated accurately, maintained their level of daily activity and improved their body condition considerably. In contrast, lizards in the treatment where the preferred body temperature could not be reached became thermoconformers, decreased their daily activity (except for gravid females) and did not increase their body condition. Our results show that lizards can indeed change their thermoregulatory strategy but stress that maintaining the preferred body temperature and, thus, optimising the physiological performance have high priority in lizard behaviour.
Original languageEnglish
JournalBehavioral Ecology and Sociobiology
Issue number3
Pages (from-to)405-414
Number of pages10
Publication statusPublished - 2006
MoE publication typeA1 Journal article-refereed

Fields of Science

  • 118 Biological sciences

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