what is a term for egg laying mammals
Echidnas and the platypus are the only egg-laying mammals, known as monotremes. The neocortex makes up half of the echidna's brain, compared to 80% of a human brain. Due to their low metabolism and accompanying stress resistance, echidnas are long-lived for their size; the longest recorded lifespan for a captive echidna is 50 years, with anecdotal accounts of wild individuals reaching 45 years.