Reproductive meltdowns underlie arthropod extinctions in the face of climate change

To persist on our warming planet, arthropods will need to be able to survive and successfully reproduce under the new temperature conditions. However, whereas most prior research has considered whether rising temperatures will cause species to surpass their lethal thermal limits, recent work shows that thermal disruptions to reproduction can also lead to arthropod extinction. Here, we summarize evidence for the 'reproductive meltdown' of arthropod populations and describe the mechanisms that could underlie these extinctions. In some cases, reproductive meltdowns appear to occur when rising temperatures cause adults to forgo breeding activity in favor of thermoregulation. Reproductive meltdowns also arise when heat sterilizes adults. Additionally, new work shows that a species' exaggerated weaponry and colorful ornamentation can influence its heating and cooling rates, thereby modifying its extinction risk on a warmer planet. Ultimately, by ignoring thermal disruptions to reproduction, we are likely to underestimate the threat that climate change poses to arthropods and overestimate the extent of suitable habitat for species in the coming years.