Generally, I find little to complain about when reading
anything published by Penguin, and this is a quibble, I suppose, but Gorgon, by
Peter D. Ward (Penguin, 2004), once finished, seemed somewhat deceptively
titled. The rather long subtitle (The Monsters That Ruled the Planet Before
Dinosaurs and How They Died in the Greatest Catastrophe in Earth’s History)
might better have been something like “Deciphering the Greatest Catastrophe in
Earth’s History” as the book focuses not on the animals per se but on the
author’s involvement in work in South Africa researching the great Permian
extinction (an earlier and more pervasive extinction than the better known and
much later Cretaceous–Tertiary mass extinction that killed off the dinosaurs
about 65 million years ago; the Permian extinction occurred about 250 million
years ago). While fossilized gorgons and other animals play a role in the story
as chronological markers, the book tells us little about what these creatures
were like—failing to satisfy expectations raised by the title and by text on
the back cover of the book. I also noted six or seven typographical errors,
which is quite unusual in a Penguin publication. Penguin texts are generally
perfect in a typographical sense.
The book is worth reading nevertheless—for its examination
of the causes of the Permian extinction—including a new (at the time of
publication) theory to explain it—and for its look at some of the men and women
who endure hardship in remote places to try to find answers to questions about
the biological history of our planet. At the same time, it includes some nicely
wrought descriptions of South Africa’s Karoo desert region and of the political
and social climate of South Africa shortly after Nelson Mandela’s release from
prison and the end of Apartheid in the country he later presided over.
Research by Ward and others seems to point to a number of
important conclusions. First, it refutes the idea that the Permian extinction
was slow and gradual (until lately, a widely accepted notion). At the same
time, the data seem to refute the idea that it was primarily the result of a
massive meteor impact, now the generally accepted explanation for the later
Cretaceous–Tertiary extinction. Ward lays out a theory suggesting that the mass
extinction was caused by a rapid increase in atmospheric temperature and carbon
dioxide and an attendant decline in oxygen levels, these changes the results of
a number of factors, which may have included an asteroid impact, although not
one big enough to have been responsible for the extinction on its own.
He suggests that the survival and later flourishing of the
dinosaurs can be explained by pre-existing adaptations in precursor species
that allowed them to acquire oxygen more efficiently than competitors, and this
is consistent with the idea that birds (with similar adaptations: mainly
complex lung systems with ancillary airsacs that extend even into hollow bones
in some parts of the body) are the descendants of certain types of dinosaur.
Essentially, he believes the Permian extinction reflects a wholesale failure of
life on Earth to survive a sudden increase in heat coupled with a decline in
available oxygen. He closes the book asking whether the period of abnormally
low oxygen beginning around the time of the Permian extinction might have
implications for the development of other adaptations—namely live birth and
warm-bloodedness. I have yet to encounter any subsequent material that
discusses these ideas (this book is already 15 years old, and based on research
done as much as 25 years ago), so it’s hard for me to judge the reception they
have found. I would be interested to learn what further evidence the scientific
community has turned up (or not) since Ward’s conclusions were advanced.