No, it doesn’t upset the applecart. But the view that Evo-Devo (Evolutionary Developmental Biology) gives us is potentially as exciting as the microscope and the telescope were in the seventeenth century. It is the study of the deep genetic relationships between different organisms, and it has led to some astounding insights in evolution and the way it works . And of course the knowledge gained could help us in all sorts of ways.
Ever since the early nineteenth century, scientists had noticed the remarkable similarities between the embryos of wildly different creatures such as sea squirts and elephants. But the was no molecular or genetic explanation as to why. However, the twentieth century revolution in molecular genetics and it associated technologies have changed all that to reveal some astounding insights:
*The same genes have been conserved for hundreds of millions of years, for the same purposes. For example the Distal-less gene complex is implicated in the structures which let such diverse creatures as flies, fish, chickens and sea urchins to get about. And everything else of course.
* So the main structural genes seem to evolve little and slowly. The big changes seem to be in the way they are switched on and off
* This in turn suggests it could be possible to to produce a reliable genetic portrait of the last common ancestor of all animals and the way it moved. Could this have been in the late Pre-Cambrian Ediacaran fauna?
*Is it possible that, at least early on, environmental influences were being “picked up” and conserved by the epigenetic systems around the core genomes? Well bless my Lamarckian socks if that one’s true!
This article in Wikipedia is a great starting point , but there’s plenty more out there if you want to give it a try. Go on-thinking about things in new ways will keep you young!
#evolutionary developmental biology #precambrian #ediacaran #repressor #dna #rna #genes #epigenetics
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