Millions of us will be sitting down to enjoy a good meal and great company today, followed by gravy drenched sandwiches for the rest of the week. The centerpiece of the traditional Thanksgiving feast on many US tables will be a stuffed and roasted Meleagris gallopavo, better known as the domestic descendant of the American wild turkey. It's an appropriate choice. M. gallopavo was highly valued by Native Americans and is a true blue, red-blooded American meal. One founding father was so taken with it that he proposed the turkey as our national bird, instead of what he considered the less admirable Bald Eagle:
For the Truth the Turkey is in Comparison a much more respectable Bird, and withal a true original Native of America ... a Bird of Courage, and would not hesitate to attack a Grenadier of the British Guards who should presume to invade his Farm Yard with a red Coat on. -- Benjamin Franklin January 26, 1784
Birds have one of the most interesting evolutionary tales in all the animal kingdom. If it could be summed up in one word, that word might be ... dinosaur! It happens that early paleontologists were keen on the dino-bird relationship. But over the next few decades, as larger and less bird-like terrible lizards were unearthed, the dino-bird idea faded away. Now it's come roaring back and it's easy to see why.
Artist's impression based on the feathered dinosaur fossil Anchiornis huxleyi, discovered in north-eastern China, Courtesy of the Guardian.
Fossils of dinos in all shapes and sizes with beautifully preserved feathers have been found! Complex structures like feathers could hardly have evolved twice. Not all paleo-ornithologists are convinced that birds evolved from dinos -- which came first, the chicken ancestor or the raptor egg? -- but most everyone agrees that either birds evolved from a type of raptor or some species of what we call raptors evolved from early birds. The smart money is on the former, but the two ideas are not completely exclusive. In the later Jurassic and early Cretaceous, with a young, rich, and shallow Atlantic ocean a few hundred miles wide sprinkled liberally with tropical islands and archipelagos, natural selection had ample opportunity to sculpt and whittle away on isolated populations of flightless birds. It's possible that early birds, many still equipped with atavistic teeth and claws, could have given rise to species that are dead ringers for traditional terrestrial dinos.
One of the neatest things about birds is their supercharged respiratory system. Because of a complex system of bony air pockets and some innovative piping, fresh oxygenated air flows over avian lung tissue when they inhale and when they exhale. If birds inherited that nifty adaptation from early dinos, it helps explain why birds are such powerhouse fliers today and why dinos came charging out of the gate and quickly grew to dominance in the oxygen depleted aftermath of the devastating Permian-Triassic extinction 250 million years ago. It also suggests your average raptor may have had the best of both metabolic worlds; able to rest with the efficiency of a crocodile but rev up and chase down prey like a lion.
In fact, birds are so closely related to dinos that our best shot for creating a living analogue lays not in cloning Velociraptors from ancient DNA, but in the genes of a modern avian like the scrumptious one sitting on your holiday table. By suppressing some genes and freeing others, it's conceivable that a sort of dino-chicken combo might be created. Imagine a giant muscular carnivorous turkey, maybe with a mouth full of big pointy teeth and four feathered limbs tipped with razor sharp claws. The kind of creature that might turn the tables on us hairy bipedal rats, giving a newer, macabre meaning to gobble-gobble: For thou art crunchy and taste good with ketchup.