How the echidna lost its venom

Physiological, molecular and fossil evidence suggests that ancestors of both platypuses and echidnas were venomous.

Male platypuses and echidnas both secrete from spurs in their hind quarters. Platypuses inject venom into competitors, but the function of the echidna’s spur and secreted substance has been unclear until now.

Collaborative research undertaken by the University of Sydney revealed that the echidna’s spur has evolved to be more like a scent gland, used to communicate during breeding.

Read more at University of Sydney