By STEVE ZARA
Added: Fri, 24 Dec 2010 22:38:45 UTC

I was shopping in a local Morrisons when the label on a packet of frozen food caught my eye: "Turkey dinosaurs". They are some vague pulp of turkey made into dinosaur shapes so as to appeal to children. A bit of fun.

It is good taxonomy though? From what we know of birds, it seems a tautology, because as far as most experts are concerned, birds aren't descended from dinosaurs, birds are dinosaurs. Specifically, therapod dinosaurs. Even more specifically, birds are coelurosaurs, a group which includes Tyrannosaurs.

This gives a new perspective to the mass extinction of 65 million years ago. The object (asteroid or comet) that hit the Earth has been mis-named as the Dinosaur Killer. One of its main effects seems to be to wipe out most of the larger species. Animals which could burrow, or swim, or were in very large numbers seem to have been the survivors of the extinction event. Those animal species included small dinosaurs.

Millions of years later large dinosaurs re-appeared, such as Gastornis - up to two metres tall, and with a savage beak that may indicate that it was a predator. Other dinosaurs continued evolving and spreading into all kinds of niches.

Perhaps "bird" is an arbitrary label for post-extinction dinosaurs. What we do know is that dinosaurs remain a fantastically successful group of animals. They are the great flyers, and migrators. They can even live in vast numbers on lands that few mammals can deal with (think of penguins).

Some dinosaurs show considerable intelligence (the corvids). Another dinosaur can come close to speech (parrots). One dinosaur is a symbol of peace (the dove), another of summer (the swallow).

For 230 million years dinosaurs have been a dominant form of life on our planet, and there is no sign of an end to the dominance.

So now we eat dinosaur flesh shaped into dinosaur shapes to entice children.

At a time of year when millions will be cooking and eating the traditional meal of roast dinosaur, I'll wish you all a very happy Christmas!

TAGGED: BIOLOGY, EVOLUTION