F Rosa Rubicondior: Bird Chicks Can Be Reverted To Grow Dinosaur Feet

Wednesday 27 May 2015

Bird Chicks Can Be Reverted To Grow Dinosaur Feet

Image credit: Universidad de Chile
Skeletal plasticity in response to embryonic muscular activity underlies the development and evolution of the perching digit of birds - Scientific Reports.

Following close on the publication of a paper showing that if a couple of genes are switched off in their embryological development, hen chicks can be reverted to develop a dinosaur face instead of a chicken face, comes the equally devastating news for creationists that a developing chick can be reverted to develop dinosaur feet.

It would be the act of an idiot designer to design birds as dinosaurs first, then have to have a new layer of design to switch the dinosaur design off and make a bird instead. It would be a bit like designing a car but leaving the shafts for the horse on, only to have to saw them off before the car could be driven. Such a designer could barely be trusted to design a teapot, let alone a Universe.

But, if we are to believe the Intelligent Design' hoax, this is the sort of designer they claim is omniscient. It would be laughable if so many poor dupes hadn't been fooled into thinking this hoax is not only a science but a science which proves they are so important that a magic designer made them especially and created a Universe just for them.

Meanwhile, science continues to put up evidence that not only falsified the entire hoax but makes it look more and more ridiculous. And the creationist industry has to become more and more inventive and devious to keep people believing the hoax and stumping up money for the hoaxers. This paper is just one example:

Most birds have an opposable digit 1 (hallux) allowing the foot to grasp, which evolved from the non-opposable hallux of early theropod dinosaurs. An important morphological difference with early theropods is the twisting of the long axis of its metatarsal. Here, we show how embryonic musculature and the onset of its activity are required for twisting of metatarsal 1 (Mt1) and retroversion of the hallux. Pharmacologically paralyzed embryos do not fully retrovert the hallux and have a straight Mt1 shaft, phenocopying the morphology of early tetanuran dinosaurs. Molecular markers of cartilage maturation and ossification show that differentiation of Mt1 is significantly delayed compared to Mt2-4. We hypothesize on how delayed maturation may have increased plasticity, facilitating muscular twisting. Our experimental results emphasize the importance of embryonic muscular activity in the evolutionary origin of a crucial adaptation.


What this paper shows is that a small change occurred in bird development which keeps a small bunch of cartilage cells dividing for longer than they did in dinosaurs, so, when the developing chick's muscles start to work, the rear toe is twisted by muscle action and develops into a rear-facing opposable toe so the bird can grip a perch. In theropod dinosaurs, this toe was almost vestigial, rather like a dog's dewclaw.

The researchers paralysed developing chicks' muscles at the key time, and the chicks grew a dinosaur foot instead. Incidentally, this is also a good example of how muscle action can bring about a morphological change, especially in the developing embryo.

I know I keep asking this sort of question and never get a rational answer (lots of abuse of course but nothing remotely sane) but I'll ask it yet again, if only to illustrate the vacuosity of the Intelligent Design hoax and its complete lack of any explanatory powers, but is there an Intelligent Design hoxer of one of their dupes who can give a rational answer to why any designer, let alone a supposedly intelligent, omniscient one would be so stupid?


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