Locomotor behavior of wolf spiders in the paramo

Ectothermic animals depend on ambient temperature to regulate internal
temperature. This dependence affects their ecology and behavior, including
locomotion, foraging, and reproduction. Additionally, ectotherms are more
vulnerable in environments with extreme hourly temperature fluctuations,
and their activity patterns likely match those of favorable temperatures.
Here, we studied Pardosa wolf spiders (Lycosidae) in the highland tropical
paramos of Costa Rica. We tested two hypotheses to elucidate the drivers
of variation in locomotor behavior. First, we tested if locomotor behavior
is driven by temperature variation. Spiders experimentally exposed to
higher temperatures (30°C) moved 3.96 times faster than those exposed to
lower temperatures (7°C). Second, we tested if locomotor behavior is
modulated by the maternal care strategy of these spiders. Females carry an
egg sac externally by holding it with the distal spinnerets. The egg sac
can represent up to 36% of the spider's body size. Females moved at
the same speed regardless of whether they carried an egg sac or not. This
demonstrates that the maternal care strategy does not affect their
locomotor performance. In contrast, temperature plays a crucial role in
driving locomotion. These findings expand our understanding of how
temperature fluctuations in extreme environments challenge ectotherms’
ability to escape predators and locate potential mates and food.