Calling citizen scientists: more data needed to protect echidnas

These masters of disguise are some of the world's oldest surviving mammals, but they are threatened by habitat loss, traffic and feral cats - and they need our help

They may be one of the world's oldest surviving mammals - around for at least 25m years - but scientists don't know much about echidnas. Now researchers believe the remaining Australian population may be threatened and they need citizen scientists' help to save them.

Related: 'Fantasy documents': recovery plans failing Australia's endangered species