William Atkins
Sunday, 05 April 2009 20:18
Science -
Biology
Page 2 of 3
Greene and Oliver are calling their new hypothesis the “Genomic Drive” hypothesis. In it, they propose that species with plenty of junk DNA are more likely to survive, evolve, and diversity, than are species without a high presence of TEs (transposable elements).
The Murdoch article explains,
“Without this DNA junk, a species is effectively frozen and faces eventual extinction.”
The article compares humans and bats with respect to percentages of DNA junk. It states that the human genome contains about 46% of TEs (DNA junk).
However, bats possess less, with around 40%. Therefore, bats have less of a chance for survival, evolution, and diversity than humans.
The Murdoch researchers state that species lacking in sufficient numbers of TEs simply lacked the ability to adapt, change (such as to changing climate), and diversity.
Dr. Greene states,
“If you don’t have this junk in your genome then you can’t evolve and are stuck, thereby remaining in what is termed evolutionary stasis.” [Murdoch]
He adds,
“This would explain why almost all species control their TEs rather than eliminate them….And of course having these TEs in a genome doesn’t mean a lineage will necessarily diversify. What it does mean is that it has a much greater potential to do so.” [Murdoch]
The Genomic Drive hypothesis by Greene and Oliver also overcomes a perceived weakness in the theory of evolution, that of it not being able to reconcile fossil records with the facts of the theory.
Specifically, Dr. Greene is paraphrased in the Murdoch University article as having said,
“… current evolutionary theory, which assumed biological lineages evolved by the slow accumulation of adaptive mutations, did not tally with the fossil record.”
“However, the ‘Genomic Drive’ theory provided a significant explanation for the way new species arose abruptly and periodically.”
Page three continues.
