A revolution in the understanding
of the evolutionary process is taking place.
Epigenetic modification takes place on a generational basis in response
to changing environmental conditions. In
short, if you need fur, the organism can turn fur on in its offspring. This is of course, is called intelligent
design, although I am sure that this is not what the creationists ever had in
mind.
I imagine that some time or the
other we will determine that the brain is able to direct those changes.
It is also important to
understand that all the necessary genes are sitting there waiting for the to-go
sign. Thus the real question is to determine
if new genes are ever created above the level of a single cell. They can obviously be imported thereafter
into a higher organism.
I always though that the best way
to deal with the creationist crowd was to merely agree with them, while showing
them how it all worked. This does it
quite nicely and perhaps we can now forget all the silly controversy of the
past decades.
30,000-year-old bison bone yields new clues on climate-change
adaptation
BY RANDY BOSWELL, POSTMEDIA NEWS JANUARY 31, 2012
Thirty-thousand-year-old
permafrost bison bones from the Yukon region
of Canada
Photograph by: Handout, University
of Adelaide
A 30,000-year-old bison bone plucked from the thawed permafrost inside
a Yukon
A study published in the latest issue of the journal PLoS One describes
the Canadian specimen — a bone from the extinct steppe bison, an ancient
buffalo that disappeared at the end of the last ice age — as key to unravelling
a mystery about how "epigenetic" DNA adjustments can occur more
rapidly than full-scale genetic changes in an ecologically stressed species.
The team of six researchers, including scientists from the Australian
Centre for Ancient DNA at the University of Adelaide, made their
"world-first" findings by probing genetic markers from the remains of
six steppe bison specimens unearthed at the Yukon mine.
One of the bison bones produced high-resolution evidence that
epigenetic modifications — the switching on or off of genes, without altering a
species' fundamental DNA sequence — were occurring in the steppe bison during
the Pleistocene era, when woolly mammoths and other megafauna were
vanishing from their Arctic and sub-Arctic habitats.
"These 'epigenetic' changes can occur rapidly between generations
— without requiring the time for standard evolutionary processes," states
a summary of the research.
To reach their conclusions, the Australian team compared the bison bone
to other genetic material drawn from a 30-year-old mummified cow from New Zealand
"Epigenetics is challenging some of our standard views of
evolutionary adaptation, and the way we think about how animals use and inherit
their DNA," added project leader Alan Cooper, director of the ancient DNA
centre. "In theory, such systems would be invaluable for a wide range of
rapid evolutionary adaptation, but it has not been possible to measure how or
whether they are used in nature, or over evolutionary time scales."
ACAD researcher Bastien Llamas, lead author of the study, noted that
"standard genetic tests do not detect epigenetic changes, because the
actual DNA sequence is the same."
But he explained in the summary that the research team was "able
to use special methods to show that epigenetic sites in this extinct species
were comparable to modern cattle."
Llamas added: "There is growing interest in the potential
evolutionary role of epigenetic changes, but to truly demonstrate this will
require studies of past populations as they experience major environmental
changes."
In 2007, the mummified remains of a steppe bison from about 14,000
years ago were found in the Northwest
Territories
And in 2009, a team of Canadian scientists published a study in the
high-profile journal GSA Today detailing the scientific riches yielded over the
years by Klondike-area gold mines, where mining excavations have unearthed a
motherlode of ice age fossils, including mammoths, an ancient type of horse and
other extinct species.
"A concentration of mining exposures, with relict permafrost that
is locally more than 700,000 years old, provides exceptional preservation of
paleoenvironmental archives," said the study, led by University of Alberta
"Since the discovery of placer gold in the Klondike in 1896 and
the subsequent gold rush, mining has produced tremendous exposures of surficial
sediments within the Klondike goldfields,
along with the recognition of abundant Pleistocene fossil bones," the
study noted. "Hundreds to thousands of fossils are still produced every
year from placer gold mining and provide an invaluable research resource."
rboswell@postmedia.com
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