Quote:
Originally Posted by fri2219
Most species on the earth are not charismatic megafauna or plants, and reproduce asexually, since they're Prokarya.
Open Reading Frames and iRNA coding regions hop intra/inter chromosomally all the time, and even move to and from organelle genomes fairly frequently. Inter/intra chromosomal re-arrangements not only happen as an side reaction of normal regulation, especially in immune response, but as a product of unequal chromosomal replication and recombination due to retroviruses and other mobile elements such as transposons. If you're interested, look up the work of Barbara McClintock, Howard Temin, and David Baltimore.
The tempo/mode problem of evolutionary clocks has more to do with generation time than physical time. It's too ugly to explain here, but look up what Ernst Mayr has to say about it if you're really motivated. What constitutes an instant is 10 years if you're an insect, or 10 days if you're a bacterium- and the two of them make up 99.9% of the biomass on the planet.
Sorry about the graduate level molecular genetics discussion, I need to get out of my mother's basement laboratory more often.
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I was assuming megafauna for the sake of discussion, where sex is the rule rather than the exception. I'm not that dense. :P
As for chromosomal jumping, there wouldn't be any reason for jumps to just happen in one direction, right? (Sorry, I'm more familiar with macro-level evo, more used to dealing with genes as the smallest unit. XD)
That makes sense in regards to the clock, I was probably better off saying "geologic time". But either way, my point still holds, because human generation time is extremely long and few huge changes (Like the elimination of maleness) could be made in a thousand years.
Re: B-Mage
All the (human) Y-Chromosome needs to distinguish maleness (I think, someone correct me if I'm wrong) is a testosterone receptor and whatever genes are necessary to develop a rudimentary set of gonads. I hazard to think that mutations in those regions could be so destructive as to irreparably destroy those regions without correction, given that DNA is extremely high-fidelity. A series of mutations like that would be the equivalent of the Cretaceous meteor.