the rest of the body associated with the evolution of the
slender snake form that are beyond the scope of this
article. Further evidence, such as new fossil discoveries
and modern genetic studies of evolutionary history and
biogeography, will likely turn much of what we think we
know beautifully on its head.
To illustrate; the members of the order Testudines (turtles,
tortoises, and terrapins) were traditionally considered to
be true anapsids because of their lack of temporal
fenestrae. Recent molecular studies suggest that testudines
are in fact diapsids that arrived at the typical anapsid skull
condition via convergent evolution rather than shared
ancestry. However, additional evidence casts doubt on this
conclusion. And just this year, a 99-million-year-old
snake, fossilized in amber, was found in Myanmar. It is
the first Mesozoic snake found in a forested environment,
changing our understanding of their ecology and biogeog-
raphy. Such is life. Further discoveries undoubtedly await
those with a keen eye for the intricate bones inside the
noggins of snakes, both extant and extinct!
Acknowledgments.
Many thanks to John Scanlon, John McGrath, Scott
Eipper, and Donna Hemsley for essential comments on
earlier drafts. My thanks again to Scott Eipper for the use
of his photographs.
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