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 Evolution is usually omitted in scientific projections of how
global warming will affect the planet in coming decades because
genetic changes happen too slowly to help larger creatures such as
cod, tuna or whales.
Sunday's study found that a type of microscopic algae that can
produce 500 generations a year - or more than one a day - can still
thrive when exposed to warmer temperatures and levels of ocean
acidification predicted for the mid-2100s.
The Emiliania huxleyi phytoplankton studied are a main source of
food for fish and other ocean life and also absorb large amounts of
carbon dioxide, the main greenhouse gas, as they grow. Their huge
blooms can sometimes be seen from space.
"Evolutionary processes need to be considered when predicting the
effects of a warming and acidifying ocean on phytoplankton,"
according to the German-led study in the journal Nature Climate
Change.
Thorsten Reusch, an author of Sunday's study at the GEOMAR
Helmholtz-Centre for Ocean Research in Kiel, cautioned the findings
about were only for one species of algae in a laboratory test, in
water with no predators or disease.
He said it was not an argument that global warming was less serious
than expected. Longer-lived creatures, from fish to shellfish, would
not be able to evolve their way out of trouble.
A U.N. panel of scientists says that man-made greenhouse gases
emitted into the atmosphere are warming the planet. And carbon
dioxide, the main gas, turns into a weak acid when it dissolves in
water, slowly acidifying the oceans.
Last year, a study by 540 experts said that acidification was a
silent storm in the oceans and threatening life from coral reefs to
fish stocks. It said the seas could become 170 percent more acidic
by 2100 compared to levels before the Industrial Revolution.
Sunday's study showed that algae, taken from water 15 degrees C (59
Fahrenheit) warm off Norway, tended to evolve to a smaller size in
higher temperatures in experiments lasting more than a year but also
grew faster, producing a larger mass overall.
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Stephen Palumbi, a professor of biology at Stanford University, said
there was evidence that some coral reefs or sea urchins could be
more resilient than expected to ocean changes.
"What we don't know is how far these mechanisms will go. I suspect
personally that they will not solve the future climate problem
because climate is changing far too fast."
"But perhaps these abilities will give some important marine life a
few more decades than we previously thought," he said.
A U.N. panel of scientists says it is at least 95 percent probable
that manmade emissions of greenhouse gases are the main cause of
global warming since 1950, causing more heatwaves, droughts and
rising sea levels.
Opinion polls, however, indicate that many voters believe that
natural variations are to blame. The mismatch between scientific and
public opinion complicates a plan by almost 200 governments to work
out a deal to limit global warming at a summit in late 2015 in
Paris.
(Reporting By Alister Doyle; Editing by Rosalind Russell)
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