I don't know if one of the newbies is interested, the books looked unread to me, or whether someone is planning an expedition into the interior during the summer looking for feathered dinosaurs. If he, or she, is then he, or she, is most welcome to it. The interior of the continent is cold and as dry as a bone; think death valley at minus forty. It is not a place I would care to go. I have enough trouble sitting on this ice sheet; thank God for feathers!
Anyways, I have a certain fascination with dinosaurs ever since I came across a Nature or Scientific American paper written in the early seventies by Bob Bakker, who used to be John Ostrom's PhD student (you'll see the significance of Ostrom later), which, in effect, was one of the catalysts for the so-called 'Dinosaur Renaissance'; Bakker effectively said, mirroring Ostrom's views, was that everything you were ever taught about dinosaurs was wrong and a reappraisal was required.
Two of the books which I picked up, out of perhaps half a dozen or so, were a book on feathered dinosaurs and their link to birds, ie birds are the therapod's, small carniverous dinosaurs, descendents, written by a journalist (who at least has a science degree) and another about pterosaurs, flying cousins to the dinosaurs, which was written and illustrated by a professional palaeontologist; and mighty fine illustrations they are.
Now, Thomas Henry Huxley (we have met him before in Is God a Beetle?) was one of first to make a connection between dinosaurs, specifically small, predatory raptors, and birds on account of their shared anatomy; he was examining the 'London specimen' of Archaeopteryx, the so-called first bird, at the time. THH was ignored and the idea fell into oblivion; the dinosaurs were lumbering, slow-witted reptiles who grew to immense size.
To be fair to the Victorians, who had yet to fully embrace Darwin's theory of evolution by natural selection, this was not an unreasonable assumption. Most of the fossils that were found were of huge proportions, or at least that is what the press reported; fueled as they were by Cope and Marsh's so-called 'bone wars' and when confronted with Dippy, the Diplodocus carnegii, which Andrew Carnegie spent enormous sums of money creating casts of, which he could then ship out to museums around the globe, it is scarcely surprising that with brachiosaurs, stegosaurs, apatosaurs, tyrannosaurs and ceratopsians, the general concensus was big and small-brained.
Some seventy or eighty years later, enter John Ostrom; a professor of palaeontology at Yale University. In the mid-sixties, Ostrom uncovered a relatively small predatory dinosaur, about 3m in length including the tail, and about 1.5m at the shoulder, Deinonychus. (Terrible claw; named after the five inch sickle-shaped claw on its second toe which could be articulated upwards so that it didn't touch the ground when running and thereby blunt it.) The importance of this find should not be underestimated; it did after all provide the basis of the depiction of the 'velociraptor' in Jurassic Park.
Ostrom noted certain similarities between what Ostrom assumed to be a bi-pedal, running on the rear legs only, ankle joint and the ankle joint of modern birds; other correlates could also be found, not least in archaeopteryx. And so began the search to find a link between birds and dinosaurs. Although Ostrom had said that, in the absence of marked feather impressions, archaeopetryx may be easily identified as a coelurosaurian dinosaur; few paid little attention, just like THH.
And then in 1996 (until the present), finds started to accumulate from Liaoning province in China, which date to the early to mid-cretaceous and preserve fossils to a remarkable degree, much like the Solnhofen limestone which thrust archaeopteryx onto an unsuspecting world. These fossils clearly showed bird like feathers on 'reptilian' bodies as well as what can only be considered proto-feathers; the first stages to forming a true feather capable of aerodynamic flight.
The concensus is forming that not only did (at least) therapod dinosaurs, the stem clade which includes T-Rex, have active metabolisms (why else have insulation, which feathers are, irrespective of display characteristics) but they, at some point, not necessarily in the Cretaceous, maybe before, gave rise to the lineage that we call birds, or more accurately flight-capable therapods, and hence dinosuaria. There are still some dissenters, although not many, and most researchers now think that the 'feather innovation' rests entirely within the 'dinosaur/therapod' clade and that birds are now the sole survivors of a dynasty that lasted 150 million years and continues, after another 65 million years, to outnumber the number of species, mammalian to avian, by four to one. If it is 'true' (what is?) then dinosaurs stalk the earth still; they are are just not as big as they once were; thankfully!
It would be comforting, I think in a small way, to envisage Huxley and Ostrom up in Heaven, looking down and saying to themselves over a quiet beer: "We told you so! But you wouldn't listen!'
I have gone on far too long and what I have to say about my aerial cousins, the pterosaurs, will have to wait for another day; they are, however, truly wonderful illustrations. The guy has talent!
* Do you like the latin? I thought it really cool. I got it from Private Eye!
With thanks to John Pickrell (Isn't that a fish? A small pike?) for 'Flying dinosaurs'; a really good summation of current research, condensed into a easily-digested format. Pity there are no 'papers' cited, which would have been helpful for those who have subscriptions, albeit not their own, to the relevant journals
With thanks to John Pickrell (Isn't that a fish? A small pike?) for 'Flying dinosaurs'; a really good summation of current research, condensed into a easily-digested format. Pity there are no 'papers' cited, which would have been helpful for those who have subscriptions, albeit not their own, to the relevant journals
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