h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

"You may also be interested to know that currentl it is thought that HOX genes were very important in the Cambrian explosion. Organisms are thought to have gone from 1 to 2 to 4 to 8 etc in terms of the number of their HOX genes and hence were able to have an exponential increase in the diversity of their morphology."

I am - any pointers for more information?
Frogbit.

Hi, actually I'm very much less than an expert on the subject. These genes were first found in Drosophila fruitflies and were described by the way their deletion affected the growth of the fly embryos. Hence 'Hedgehog' and 'Wingless' are two of them.
The same guys later found that these same genes were in any creature that exhibited cellular diversity. From fish upwards they are the same in all animals I believe.
I got the cambrian explosion bit from the Horizon programme I saw on it. They got the Nobel prize for medicine for their work in around 1995. The human variant of Hedgehog (rather sillyily named 'Sonic Hedgehog' was at one point on clinical trials for the treatment and even reversal of Alzheimers disease as it can be injected into - say - a muscle cell and the cell is transformed into a neuron.

A web search for HOX (short for Homeotic Box) will probably illuminate you further.

Thanks for that Orcus. Poor old drosophela, she always gets it in the neck.
The reason for my interest was the HOX idea in relation to the Cambrian Explosion. Previous to HOX, it has always had people scratching their heads in perplexion. And I'm sure it will continue to do so...
What's Josh's game then? I notice he very rarely pops his head up in the PR thread. Perhaps he's just trying to found converts
Not much luck here, then.

Well the cambrian explosion bit is only theory, but then, anything relating to something that happened 4000 million years ago is likely to forever remain that way.
It is a nice way of explaining why there was suddenly an explosion in the diversity of species - a rapid increase in transcription factors allows a rapid increase in cell diversity and hence morphological complexcity.
Put this with the fact that the cambrian explosion happened rather soon after the mass exticntion of the trilobites and other creatures then theory also says that there were massive new habitats for creatures to suddenly exploit as everything else had suddenly been wiped out. Plenty of room therefore for new and exciting creature to suddenlt evolve and fill niches.

I think rather more kindly of Josh. I have no objection to someone putting in an article on creation theory and saying why people believe in it. I also have no objection to people pointing out holes in Darwinism and more advanced evolutionary theory. That is why I did not object before.
However, if you're going to debunk science then getting it utterly wrong and displaying a complete lack of understanding of the subject is not the way to go about it. How can you demonstrate something is wrong if you have not the first clue of why it is wrong? Also, he's been told so many times that I got a bit fed up really

True. I wasn't being unkind, but maybe joking at his expense.
Have you read 'Wonderful Life' by Stephen J. Gould? This details the discovery of the Burgess shale and the Cambrian explosion.

No, I haven't read that, I must put it on my reading list

Hmm, despite the removal of *that thread* from peer review yesterday, our Josh has reposted it again! Sigh. Fondness might start wearing thin, even nice researchers like Witty Ditty are getting the hatchets out now