Spiny lava lizards, a species native to South America, spend less time wooing mates and choose their partners more hastily when exposed to warmer-than-usual temperatures, according to a study conducted by Nicola Rossi and his colleagues at the National University of Córdoba in Argentina.
During hot weather, the lizards tend to move around more during the cooler parts of the day, possibly missing out on mating opportunities with other lizards. The researchers found that in the hottest midday hours, the lizards in warmer areas were less active compared to those in cooler areas.
In a laboratory setting, male lizards did just as many push-ups regardless of temperature, but their head bobs were sporadic at hotter temperatures. Males also sought shady refuges more in the warmest condition, reducing the time they spent interacting with females. Females, on the other hand, showed a decrease in their preference for males with colorful flanks, which is a sign of sexual fitness. They also did fewer head bobs when it was hotter.
This study suggests that spiny lava lizards may not adapt quickly enough to cope with the future rate of temperature increase. As ectothermic animals, lizards are vulnerable to dramatic temperature swings that can push them beyond their physical limits.
Insights:
The study highlights how temperature affects the courtship behavior of spiny lava lizards. During hotter weather, the lizards prioritize avoiding excessive heat over mating, leading to changes in their movements and partner selection.
Males exhibit sporadic head bobs and seek shady refuges, reducing their interactions with females. Females, on the other hand, become less selective in choosing mates, which may negatively impact their reproductive success. These behavioral changes could have long-term consequences for the species, particularly as temperatures continue to rise in the future.
