Study Reveals Male 'Hoff Crabs' Use Larger Claws to Compete for Mates

Researchers find sexual dimorphism in claw size among Antarctic crabs living near deep-sea hydrothermal vents, a first for their species family.

The 'Hoff crab,' officially named Kiwa tyleri, is a deep-sea crustacean found near hydrothermal vents in the Antarctic's East Scotia Ridge.
Male Hoff crabs grow significantly larger claws than females, likely to compete for mating opportunities, marking the first observed sexual dimorphism in claw size within the Kiwaidae family.
These crabs thrive in harsh environments by farming bacteria on their hairy chests, which provide sustenance in nutrient-scarce conditions.
The study compared Hoff crabs to another yeti crab species, Kiwa puravida, which lacks claw dimorphism, suggesting differing ecological or behavioral adaptations.
Understanding these crabs' adaptations offers insights into evolution in extreme conditions and could inform research on species' responses to environmental changes.