• merc@sh.itjust.works
    link
    fedilink
    English
    arrow-up
    1
    ·
    1 year ago

    But there is no good phylogenetic definition because all the animals we call “fish”

    The challenge was to come up with a group “which includes both trout and sharks but not humans”. It seems like “gills” satisfies that pretty well.

    • Strawberry
      link
      fedilink
      English
      arrow-up
      1
      ·
      1 year ago

      Animals with gills do not form a monophyletic group.