Thoughts on Evo-Devo ....I feel that evo-devo offers some fascinating insights into our biological origins. It is interesting that on a genetic level, organisms can share nearly identical genomes, but their morphologies are distinctly different. What factors account for the shift and drift of gene expression? are internal or external factor more determining?....I would infer that environment must be a key factor; if an organism could not survive in a given environment with the activation of X gene, but could with the XX gene, then it makes sense that the XX gene would be dominant. A good example of this can be found in the artilce we read in class on the Galapagos island and the finches---their beak structure is believed to have changed in order to adapt to environmental changes (The article does not mention if there was any change in the finch's genes...but I would infer that there was not, but rather that one gene for 'beak' was being expressed more than another?) To me, this seems more like a 'passive' change in morphology due to environmental pressures. But I do wonder about the intelligence of genes....For example, viruses. The influenza virus is segmented and has the ability to 'trade', or reassort, its genes with other strains of the flu virus. This 'shift' could result in a more virulent flu strain, or even a new strain that could jump species. The influenza virus also undergoes (or, initiates?) 'antigenic drift'---alteration of its surface proteins which allow it to enter and exit host cells, as well as evade immune response. For this reason, a new flu vaccine must be developed each year. Are these shifts and drifts of the influenza virus accidental, as in 'genetic error', or deliberate for survival and proliferation? The HIV virus is a classic example of 'genetic error'---its reverse transcriptase process is highly error prone resulting in antigenic variation, thus it has an unusually high mutation rate which allows it to develop drug resistance and therefore proliferate and thrive. I do think that genes have a very certain intelligence, but that there is some greater force directing their expression and suppression. When I think about the influence that environment, an external factor, must have, I have one of those deep breathe moments one has when they realize there is no interior/exterior ....that all is connected. Sigh and Wonder.
How does Darwinism matter to me? ....I think that Darwinism ('natural selection', 'survival of the fittest') was a ground-breaking evoltionary theory for its time, but like all theories, has undergone some necessary challenges by modern day biologists. I feel that environment plays a key role in evolution, but I also feel that there are other factors involved, as discussed above. Namely, the possibility of genetic intelligence and genetic error. Biologists have illustrated that differing morphologies do not always translate into differing genomes, and more research is necessary to understand the connections (or disconnections, as the case may be). Darwin cracked the egg.
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Your blog makes me wonder too, that if some genes are able to adapt as quickly as one generation, what happens when we drastically change our environment? These species and their traits are all for the purpose of adaptability and survival. We have been altering the environment in unnatural ways for centuries. What if the green movement picked up so quickly that green house gases were eliminated twice as fast as they were created? What will happen to those species that have evolved or morphed to adapt to those gases? What happens to our natural processes of evolution when the earth could be too hot for this generation then too cold for the next?
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