One in particular put
Solnhofen on the map: Archaeopteryx, long famous as the “first true
bird.” A single feather was discovered in 1860, a tantalizing glimpse of the
creature it fell from. Beginning the very next year, a series of Archaeopteryx
fossils began to come to light, at an irregular rate, and eleven specimens
are currently recognized (one from only a few months ago). From its many dinosaurian
skeletal features, its long bony tail, and the fine teeth in its jaws, Archaeopteryx
might easily have been identified as a small theropod dinosaur, and indeed
an amateur mistakenly classified one specimen as the small predatory dinosaur Compsognathus.
However, the marvelous preservation afforded by the Solnhofen limestone has
given us specimens of Archaeopteryx surrounded by imprints of their
feathers, showing that they looked rather like a modern magpie in their
plumage. Wing feathers are asymmetrical like those of modern birds’ flight
feathers, showing adaptation for aerodynamic use. So detailed are some of the
fossils that we can even detect the fine structure of some of these feathers, showing
for instance that the fibers of the large flight feathers of Archaeopteryx were
organized via the barb-and-barbule arrangement that makes modern bird feathers
so stable and structurally effective, despite their lightweight and delicate construction.
Several years ago I
first visited the Humboldt Museum (Museum für Naturkunde) in Berlin, the home
of arguably the most beautiful Archaeopteryx fossil in the world.
Discovered in 1876or 1877, it lies on its back with its wings widespread, tail
pointing down and head swung over its back. More important, the arms (or,
should I say, wings) and tail are surrounded by stunningly clear impressions of
feathers. If I had the opportunity to save any single fossil in the world, it
would be this one. It is simply stunning.
The roast turkey that
many of you might well partake on December 25th, is a direct descendant
of a distant maniraptoran theropod dinosaur. The expression “as rare as hen’s teeth” is
based upon the reality of socketed teeth growing in the jaws of birds, courtesy
of their ancestral toothy theropod dinosaur gene being activated and socketed
teeth growing during the chicken’s development. However, you don’t need ‘hens
teeth’ to make your turkey a dinosaur…as you tuck into your meal, take time to
nibble the ‘arm’ to reveal the fingers, often still tipped with tiny claws. As
you pull the wish-bone (fused clavicles) think of Velociraptor and T. rex…who
also share this very theropod character. Its food for thought, that 65 million
years ago, it was probably our ancestors that were on the menu for the turkeys
ancestors…vengeance is a dish best served 65 million years later!
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