Evo Devo

[foodchain]

Personally I find this area of research to be fascinating. I simply could not digest all to well the idea of just genes alone when viewing life as many would have it. I don’t think such research undermines the role of genes or the overall importance they hold in life, I just could not simply digest evolution as just genes alone. Here is a wiki article on some of it, of course the internet alone is full of information on the subject for anyone interested.

"Among the more surprising and, perhaps, counterintuitive (from a neo-Darwinian viewpoint) results of recent research in evolutionary developmental biology is that the diversity of body plans and morphology in organisms across many phyla are not necessarily reflected in diversity at the level of the sequences of genes, including those of the developmental genetic toolkit and other genes involved in development. Indeed, as Gerhart and Kirschner have noted, there is an apparent paradox: "where we most expect to find variation, we find conservation, a lack of change".[10]

 

Even within a species, the occurrence of novel forms within a population does not generally correlate with levels of genetic variation sufficient to account for all morphological diversity. For example, there is significant variation in limb morphologies amongst salamanders and in differences in segment number in centipedes, even when the respective genetic variation is low.

 

A major question then, for evo-devo studies, is: If the morphological novelty we observe at the level of different clades is not always reflected in the genome, where does it come from? Apart from neo-Darwinian mechanisms such as mutation, translocation and duplication of genes, novelty may also arise by mutation-driven changes in gene regulation. The finding that much biodiversity is not due to differences in genes, but rather to alterations in gene regulation, has introduced an important new element into evolutionary theory.[11] Diverse organisms may have highly conserved developmental genes, but highly divergent regulatory mechanisms for these genes. Changes in gene regulation are "second-order" effects of genes, resulting from the interaction and timing of activity of gene networks, as distinct from the functioning of the individual genes in the network.

 

The discovery of the homeotic Hox gene family in vertebrates in the 1980s allowed researchers in developmental biology to empirically assess the relative roles of gene duplication and gene regulation with respect to their importance in the evolution of morphological diversity. Several biologists, including Sean B. Carroll of the University of Wisconsin-Madison suggest that "changes in the cis-regulatory systems of genes" are more significant than "changes in gene number or protein function".[12] These researchers argue that the combinatorial nature of transcriptional regulation allows a rich substrate for morphological diversity, since variations in the level, pattern, or timing of gene expression may provide more variation for natural selection to act upon than changes in the gene product alone.

 

Epigenetic alterations of gene regulation or phenotype generation that are subsequently consolidated by changes at the gene level constitute another class of mechanisms for evolutionary innovation. Epigenetic changes include modification of the genetic material due to methylation and other reversible chemical alteration [13], as well as nonprogrammed remolding of the organism by physical and other environmental effects due to the inherent plasticity of developmental mechanisms.[5] The biologists Stuart A. Newman and Gerd B. Müller have suggested that organisms early in the history of multicellular life were more susceptible to this second category of epigenetic determination than are modern organisms, providing a basis for early macroevolutionary changes.[14]"

 

http://en.wikipedia.org/wiki/Evolutionary_developmental_biology

[immortal]

We find conservation of genes instead of variation because the genes which are conserved helps in providing variation during several life stages of an organism. One such conservation is of microRNA which are conserved in both humans and mice. MicroRNA inhibit the mRNA and there by regulating the genes but having said that both humans and mice have similar regulating mechanisms but still we find a huge morphological difference may be factors like when and where the mRNA was inhibited may come into account and also not to forget about the Jumping genes (the transposons) which alter the genome. So its very easy to digest evolution if you look at it in an broad way and see junk things has precious. Its very hard to imagine life without these junk genes (someone has to change this name).

[foodchain]

Well I think more advances will be made along every line of biology as science gets better and better and being able to view the molecular basis of life. I think the major hurdle will be getting the ability to view wild types also, which will have to be conquered in a lab somewhere. Another issue that I am not sure of is diversity of how evolution may come about in regards to species or genomes overall.

 

"An experiment which forced E. coli bacteria to adapt or perish showed that, in a pinch, they were capable of improvising a novel molecular tool to save their skins."

 

http://www.scienceagogo.com/news/20040122185500data_trunc_sys.shtml

 

To me it would seem a large part of the role of genetics has it purely as a one way street, or genes-->organism with no model of genes<--->organism, even while the genes are a part of the organism. More novel roles of RNA are being discovered and I am sure the discoveries in molecular biology/biochemistry and evolution are simply no numerous to digest. Evo Devo just seems like the tip of the iceberg I think in what will eventually be a more profound understanding of evolution in regards to organisms if not nature in general.