Cladistic language concepts

[Ghiselin, Michael]

----------------------------Original message----------------------------
          Dear Prof. Hewson,
               An amphibian is generally a sort of compromise between
          two kinds of functional demands that allow it to switch back
          and forth between one and another habitat.  Penguins swim
          well but they waddle on land and otherwise do not do very
          well there.  Bilingual persons supposedly are adept at both
          tongues.
               Another possibility that comes to mind is
          hermaphroditic organisms.  They can function as either sex
          or both depending on the circumstance.  A lot of them are
          "sequential" hermaphrodites, switching from one role to
          another.  But there are simultaneous hermaphrodites in a
          fully functional sense: donating and receiving male gametes
          at the same time.  I suppose that bilingual persons mainly
          switch from one language to another but perhaps not
          entirely.  I am not sure whether such speculation is apt to
          lead anywhere.  But thanks.
          MG