Thursday, January 05, 2006

Tiger, tiger, burning bright

In the forests of the night,
What immortal hand or eye
Could frame thy fearful symmetry?

Anyone who thinks "Darwinism" is "just a theory" can read this and weep.
This NYT article "DNA Offers New Insight Concerning Cat Evolution" uses that old "E" word - evolution -- without a blink or a demur.
And the story is such a fascinating one -- it would be a pretty dull story to attribute the cat to so-called "intelligent design", AKA "creationism", compared to what really happened:

About nine million years ago - two million years after the cat family first appeared in Asia - these successful predators invaded North America by crossing the Beringian land bridge connecting Siberia and Alaska . . . Later, several American cat lineages returned to Asia. With each migration, evolutionary forces morphed the pantherlike patriarch of all cats into a rainbow of species, from ocelots and lynxes to leopards, lions and the lineage that led to the most successful cat of all, even though it has mostly forsaken its predatory heritage: the cat that has induced people to pay for its board and lodging in return for frugal displays of affection.
This new history of the family, known as Felidae, is based on DNA analyses of the 37 living species . . . Before DNA, taxonomists had considerable difficulty in classifying the cat family. The fossil record was sparse and many of the skulls lacked distinctiveness . . . [the research team]has been able to reconstruct a series of at least 10 intercontinental migrations by which cats colonized the world. The cheetah, for instance, now found in Africa, belongs to a lineage that originated in North America and some three million years ago migrated back across the Bering land bridge to Asia and then Africa. Dr. O'Brien said the cats were very successful predators, second only to humans, and quickly explored new territories as opportunity arose. Sea levels were low from 11 million to 6 million years ago, enabling the first modern cats, in paleontologists' perspective (saber-tooth tigers are ancient cats), to spread from Asia west into Africa, creating the caracal lineage, and east into North America, generating the ocelot, lynx and puma lineages.
The leopard lineage appeared around 6.5 million years ago in Asia. The youngest of the eight lineages, which led eventually to the domestic cat, emerged some 6.2 million years ago in Asia and Africa, either from ancestors that had never left Asia or more probably from North American cats that had trekked back across the Bering land bridge.
Sea levels then rose, confining each cat species to its own continent, but sank again some three million years ago, allowing a second round of cat migrations. It was at this time that the ancestors of the cheetah and the Eurasian lynxes colonized the Old World from the New . . .
Even the most deeply religious person should be able to see the hand of God in such a fascinating history.
Did He smile His work to see?
Did He who made the lamb make thee?
Tiger, tiger, burning bright
In the forests of the night,
What immortal hand or eye
Dare frame thy fearful symmetry?

(Thanks to Americablog for highlighting this story.)

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