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re: tiny gekko quiz: results



David Peters (davidrpeters@earthlink.net) wrote:

<A couple of days ago I challenged all those who thought they could
determine juvenile from adult by sight by posting a line drawing of a
gekko at www.pterosaurinfo.com/gekko.html. I asked if anyone could
identify the size and the ontogenetic age, whether in days or years.

  No one even tried.

  Case closed. (Really, it was pretty darn near impossible. )>

  Eh, a gekko specialist probably could. This is a dinosaur mailing list,
coulda tried that with lizard specialists or herpetology mailing lists.
Case closed because no non-specialist could tell the difference? Naw.
'Sides, more than a few lizard groups have been developmentally recalled
as paedomorphic, while I am not sure wether this occurs in gekkonids.
Recall the paedomorphic mud puppy (*Necturus*), which at adulthood retains
its gills and juvenile breathing apparatus, despite other amphibians
showing development through neoteny.

<BTW the snout vent length of the traced gekko is 11mm. It is a hatchling.
And it was photographed on the tip of someone's finger. Pretty amazing.
It's about as small as amniotes get.>

  There's an adult lizard in Cuba called *Sphaerodactylus* that gets about
as small, two can curl on a dime. Hatchlings are far smaller.

  My own BTW: while the feline anatomy comparison continues, despite
looking for a new apartment and a computer that hates me, check out:

  Andrew Abbie (1947), Headform and human evolution. _Journal of Anatomy_
81: 233-258. In it there is a wonderful figure showing hominoid braincase
transformation both ontogenetically and from monkeys (*Macacus*) to us
(*Homo*). There is a peculiar ontogenetic as well as neotenic change in
calvarium shape, the formation of the chin, dental arcade, and facial
angle.

  Cheers,

=====
Jaime A. Headden

  Little steps are often the hardest to take.  We are too used to making leaps 
in the face of adversity, that a simple skip is so hard to do.  We should all 
learn to walk soft, walk small, see the world around us rather than zoom by it.

"Innocent, unbiased observation is a myth." --- P.B. Medawar (1969)


                
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