A primary anti-predator adaptation is crypsis, in which animals lower their visibility to predators—often through camouflage—to reduce the risk of predation. Alternatively, prey species may employ strategies such as aposematism (advertising unpalatability) or mimicry (imitating other organisms). Given that domestic animals typically experience reduced predation pressure compared to their wild counterparts, they are expected to exhibit less developed cryptic coloration. To test this prediction, we compared dorsal and ventral crypsis between domestic and wild black-spotted frogs (Pelophylax nigromaculatus). Our results showed that domestic males displayed significantly weaker dorsal crypsis than wild males. In contrast, no statistically significant difference in dorsal crypsis was observed between domestic and wild females. These findings suggest that the reduction in dorsal crypsis among domestic males may be attributed to relaxed predation pressure and shifts in dietary resources within human-modified environments.
Wen Bo Liao (2026) studied this question.