🚀 go-pugleaf

  Another bit of trivial but possibly interesting information from the
article, which I forgot to include, so I'm doing it now, is:-
    
        WhY did brain size remain unchanging for 150 million years?

Mammal brain size barely changed between 200Ma (when mammals evolved)
until 65 Ma. Why?
A possible answer comes from some studies conducted on modern birds.
It was found that songbirds which stored food had a much bigger 
hippocampus than in non-storers.  Birds most active at twilight have 
larger olfactory bulbs than other species.

    The strange thing is that for all these birds the total brain
size is about the same.  Enlargement of one area is always accompanied 
by a reduction in size of one or more other areas.  This indicates that 
there might be constraints on total size.

   Whatever the solution of this is, it might explain why entire classes
of animals have approximately the same brain size.   It would then raise
the importance of those special times (200 Ma and 65 Ma for mammals and
2.5Ma for humans) during which groups of species broke out of their
contraints on brain size.