• JasonDJ@lemmy.zipEnglish
    33·
    6 days ago

    Do you secrete milk from mammary glands?

    Bc that’s like legit the only requirement. We set the bar low. Not like those elitist avians.

    • prole@lemmy.blahaj.zoneEnglish
      3·
      5 days ago

      I was always taught live birth was also one of the requirements. Are there any other exceptions besides platypus?

    • WhiskyTangoFoxtrot@lemmy.worldEnglish
      51·
      5 days ago

      Well, you have to be descended from a particular branch of the evolutionary tree that has the ability to secrete milk from mammary glands. If, say, a mollusc independently evolved milk production that wouldn’t make it a mammal.

      • JasonDJ@lemmy.zipEnglish
        2·
        5 days ago

        They wouldn’t independently evolve mammary glands, because only mammals have mammary glands, and they are not mammals, but mollusca.

        I’d say that’s a bit of a chicken/egg situation, but I don’t think we need to bring in more classes.