A way evolution can happen—that is, how information gets shared
|July 10, 2013||Posted by News under Evolution, News, horizontal gene transfer|
from The Scientist , we learn,
In what appears to be a novel form of bacterial gene transfer, or conjugation, the microbe Mycobacterium smegmatis can share multiple segments of DNA at once to fellow members of its species, according to a study published today (July 9) in PLOS Biology. The result: the generation of genetic diversity at a pace once believed to be reserved for sexual organisms.
The researchers found that, after the transfers, up to a quarter of the recipient bacteria’s genomes were made up of donated DNA, scattered through the chromosomes in segments of varying lengths.
According to the authors, the diversity resulting from distributive conjugal transfer approaches that achieved by meiosis, the process of cell division that underlies sexual reproduction. “The progeny were like meiotic blends,” said Derbyshire. “The genomes are totally mosaic.”
As to where the “original” information came from, in a sense, that is like asking how life itself originated. It is a separate question from the evolution of life thereafter.
That is, if we want to study evolution, we want to study the mechanisms by which life forms change over time. We can do so even if we do not know how the information they have altered, traded, or expunged* originated. Good thing, that, as it is likely much harder to find that out.
Note: Perhaps expunged only temporarily, as in the case of the blind cave fish whose offspring’s eyes reappeared when they were hybridized.