In male echidna there are nine sex chromosomes while platypus has an even 10. The male echidna has five X chromosomes, but only four Y chromosomes, whereas the male platypus has five X and five Y).

In male echidna there are nine sex chromosomes while platypus has an even ten. The male echidna has five X chromosomes, but only four Y chromosomes; whereas, the male platypus has five X and five Y).

Scientists captured images of an elusive echidna named after the British biologist Sir David Attenborough for the first time in over 60 years. Attenborough's long-beaked echidna was last recorded ...