Last night on PBS, a new series premiered called "The Shape of Life." I
thought that it was surprisingly well done. Even more relevant to this group
perhaps is that it was sponsored primarily by the David and Lucille Packard
Foundation, with other funding coming from the National Science Foundation
and the John D. and Catherine MacArthur Foundation.

It's a six-part series. The first two hour-long episodes aired last night. I
think that its thematic construction is very clever: it's the  first
<whatever>. The first episode dealt with the evolution and organization of
the first animals, the basal root to all subsequent animal species, the
sponges. Although sponges lack almost all of the qualities that we associate
with higher animals, they were the first multicellular colonial, cellularly
task-partitioned animals on the planet.

The second episode dealt with the cnidarians (sea anenomes, jellyfish,
corals, etc.) (don't pronounce the "c" in Cnidaria). These animals were the
animals first to invent muscularization and innervation (nerves). The
following link illustrates (and somewhat obscures at the same time) the
relationship of all animals (called the "Metazoa") to one another, in order
of their invention:

  http://tolweb.org/tree?group=Animals&contgroup=Eukaryotes&dynnodeid=2406

The diagram is drawn as a cladogram, a common format in biology. What
cladograms do not convey well is a sense of time and sequential invention.
Rather, all they are meant to illustrate is a sense of connectedness and
relationship of one group to another. You have to supply a sense of history
and time, meaning tens of millions of years, when you view these diagrams.

The next two hours of the series will focus on the first hunters (predators)
and the first animal invaders of land.

The Packard Foundation is the major supporter of the Monterey Bay Aquarium
and its research arm, the Monterey Bay Aquarium Research Institute
(http://www.mbari.org/) and this series very subtly supports both its mission
and its results, but that's perfectly natural too (in every sense of the
word). Life began in the oceans, with three primary body plan architectures
resulting: exoskeletons, endoskeletons, and hydroskeletons. The calcification
of tissues that makes up our hard structure began a half billion years ago in
the coral cnidarians.

Wirt Atmar

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