High temperatures are associated with decreased immune system performance in a wild primate

Rising temperatures due to climate change are predicted to threaten the
persistence of wild animals, but there is little evidence that climate
change has pushed species beyond their thermal tolerance. The immune
system is an ideal avenue to assess the effects of climate change because
immune performance is sensitive to changes in temperature and immune
competency can affect reproductive success. We investigate the effect of
rising temperatures on a biomarker of non-specific immune performance in a
wild population of capuchin monkeys and provide compelling evidence that
immune performance is associated with ambient temperature. Critically, we
found that immune performance in young individuals is more sensitive to
high temperatures compared to other age groups. Coupled with evidence of
rising temperatures in the region, our results offer insight into how
climate change will affect the immune system of wild mammals.