November 11, 2008
Posted: 01:29 PM ET
Galapagos tortoises and finches may be the first creatures that come to mind when we think of evolution. But as intriguing as Charles Darwin’s discoveries were, he didn’t write the only book on evolution. In fact, a lot of books on the subject haven’t even been written yet.
New understanding of evolutionary concepts could help humans understand contemporary problems, from renewable energy to health care. (Photo by Matt Cardy/Getty Images)
Scientists have only discovered and named about ten percent of the plant and animal species on earth.
“There’s a huge amount to learn, we have not scratched the surface,” said Professor David Lynn, chair of the chemistry department at Emory University.
Lynn was among organizers of an Emory workshop, “Evolution Revolution: Science Changing Life.” It was aimed at high school teachers trying to rev up their students’ interest in how evolution is changing our world now.
The gathering is getting a head start on celebrating Darwin’s 200th birthday next year. It’s also the 150th anniversary of “On the Origin of the Species,” Darwin’s pioneering research on one of the most important concepts in science.
Darwin described natural selection, the concept that individuals who are better adapted to their current environment have an advantage over those not so well adapted. "Survival of the fittest" is sometimes used to describe natural selection. But it's not always the biggest and toughest who win in the long run. Evolutionary fitness sometimes involves cooperation with other organisms and the ability to reproduce and pass those genes on. Researchers in scores of different fields are constantly updating this elegant idea.
“Technology moves very quickly, and even scientists have a hard time keeping up,” said Lynn, professor of biomolecular chemistry. That’s why the evolution workshop reached out to the community, and to people in the arts as well as science.
Understanding evolution today could help with contemporary challenges, from harnessing new biofuels to understanding communicable diseases to developing new strategies for health care.
(And before you ask, yes, the Emory scientists did discuss with teachers how to answer questions about creationism and “intelligent design.” But no, that wasn’t the focus of their meetings. )
Mostly, said Lynn, “Teachers were interested in the best way to teach this marvelous discovery, with questions like, ‘How do I explain this concept to my tenth graders in a digestible, artistic way?’”
Wilson is known as the “father of biodiversity” (as well as the guy who is so passionate about ants he wrote a 700+ page book about their behavior that earned him the Pulitzer prize for literature).
Wilson provided a glimpse into Darwin’s life, including his five- year journey on H.M.S. Beagle, from 1831-1836.
“He was a 21 year old, newly escaped from Cambridge University, on a five year journey with no TV, no radio, no newspapers,” said Wilson.
The world, Wilson said, was Charles Darwin’s to possess. And perhaps, during his six weeks in the Galapagos Islands, came his “aha” moment. The captain pointed out that the turtles, and the finches, were different from island to island. Which got Darwin thinking, “Maybe they’re changing?”
By 1838 Darwin had conceived of evolution by natural selection. In 1871 he published “The Descent of Man,” applying the theory directly to human beings. But members of Victorian society were limited in their embrace of scientific theory. Most folks were okay with plants and other animals evolving. But, said Wilson, “They were scandalized by apes as OUR ancestors.”
But the reason Darwin’s work holds up today, said Wilson, was because he was the epitome of a disciplined scientist.
“This man was irritatingly accurate. He was very careful.”
November 10, 2008
Posted: 09:29 AM ET
The ozone hole over the Antarctic, which grows to its maximum annual size in September, peaked at the fifth-highest size ever since measurements began in 1979 this year, according to scientists at the National Oceanic and Atmospheric Administration.
But experts say that the "fifth-largest" designation may not necessarily be bad news at all. They're sticking to predictions that the ozone hole will repair itself over the rest of the 21st Century. Colder-than-average temperatures and strong high level winds helped widen the hole this season. Warmer weather as the Antarctic summer starts up helps close up the hole each year.
It's been nearly four decades since the first research drew links between man-made chemicals and destruction of ozone in the upper atmosphere. Chlorofluorocarbons and freon - once widely used in air conditioners and spray cans respectively, were among the substances that broke down stratospheric ozone - the key to protecting us from harmful solar radiation. Projections indicate that a thinning ozone layer could lead to increases in human skin cancer, eye cataracts, and other maladies. Dutch scientist Paul Crutzen and Americans Mario Molina and Sherwood Rowland shared the 1995 Nobel Prize for Chemistry for their discoveries.
Global concern over ozone damage led to what is widely regarded as a remarkably successful international treaty. The Montreal Protocol was ratified in 1987 and took full effect nine years later, banning most uses of ozone-destroying chemicals.
Scientists have reported a substantial reduction in the levels of ozone-destroying chemicals reaching the stratosphere. But CFC's, freon, bromides, and other ozone-eaters are particularly long-lasting, and may take much of the rest of this century to dissipate. "The decline of these harmful substances to their pre-ozone hole levels ... will take decades," said NOAA chemist Stephen Montzka.
Translation: Don't lose the sunscreen. Ozone layers have thinned planet-wide, and during the late-winter weather in either hemisphere, ozone protection reaches its lowest levels near the poles. Less ozone in the upper atmosphere means more exposure to the ultraviolet radiation that can cause skin cancer.
NOAA's Ozone measurements page can be found here
NASA offers daily updated graphics and animations on the size of the ozone hole here.
Peter Dykstra Executive Producer CNN Science, Tech & Weather
November 7, 2008
Posted: 11:06 AM ET
Squirrels at the University of California-Davis have it made.
5300 acres of lush habitat.
The eastern fox squirrel is living large on the University of California Davis campus. Wildlife scientists will use a contraceptive vaccine to try to control the population. Photo courtesy UC Davis
More than a few crumbs from students and faculty who enjoy meals and snacks outside.
(And we're not talking the average "frugal student" ramen noodles and peanut butter and jelly. UC-Davis is home to The Robert Mondavi Institute for Wine and Food Science.)
With nary a predator, there's been a population explosion of the non-native eastern fox squirrels, from zero to about 400 in the past seven years. And now there's worry the critters might get more aggressive, biting the collegiate hands that feed them. Squirrels can carry bacteria that is harmful to humans. And an unchecked population could become a threat to the regional economy, spreading to nearby farmland and chomping away at the local fruits and nuts.
When college officials searched for answers to these potential nuisances, they had to go no further than scientists on campus.
And as one might expect from a campus in California, the plan is to control the population with no harm to the animals involved.
"This new birth control method may potentially help control squirrels or other species, such as white tailed deer," said Sara Krause, a doctoral student in ecology who designed the plan.
"If we can test a birth control method and find it safe and effective, there's a possibility of it being a breakthrough method in both urban and suburban areas," she said.
Continued unchecked procreation and expansion of their territory could mean farmers and ranchers would put an end to the invasive fox squirrels permanently. Squirrels can do serious damage to almond and walnut orchards.
The birth control method being used is a vaccine, called GonaCon.
Krause explained that it's an immunocontraceptive vaccine, blocking the pathway to the production of sperm and eggs. One shot leaves the animals sterile for about two years. And the same vaccine works on both males and females.
(Now there's a concept that every female on the planet can appreciate.)
Krause and others have just begun placing 20-40 humane traps around the campus. The traps will be checked two to four times a day. On this first round, captured animals will be examined, marked with a nontoxic dye, and let go. The squirrels will be observed until next summer, when they'll be re-captured. Then, some will get the contraceptive injection, others a placebo. Again, they'll be set free to roam the campus.
If the experiment works as planned, the number of squirrels will decline to a sustainable number within ten years. And federal wildlife biologists could use the contraceptive on other prolific progeny producers.
November 5, 2008
Posted: 12:22 PM ET
An eight-year presidency is coming to an end, and so is a two-year campaign full of hope, mud, hockey moms and long-forgotten candidates (Where have you gone, Vilsack and Tancredo?). But in the end, "change" is the word of the day.
What will an Obama presidency mean for science and tech?
The transition from a Bush Administration to a Barack Obama Administration implies enormous policy differences in just about every one of the issues we cover in this blog.
Here are some questions for the next four years:
Science: The Bush Administration drew heavy criticism for allegedly censoring or softening federal scientific reports on global warming, endangered species, and other issues when the science didn't match Administration policy. Will Obama clean this up? Or will he draw fire from the opposite political direction?
Space: The Space Shuttle faces mandatory retirement in two years. Is Obama, and is America, ready to commit the money to continue exploration in the wake of our financial meltdown?
Tech: From the classroom to the R&D lab, concerns are mounting that America has lost its research and innovation mojo. Can the new administration turn this around?
Environment: Both Obama and McCain drew sharp distinctions with the Bush Administration on addressing global warming. Obama's campaign called for 80 percent reductions in U.S. greenhouse gas emissions by the year 2050. Are we ready? Can he deliver?
Energy: Obama belatedly, and not too enthusiastically, embraced the possibility of expanding offshore drilling during the campaign. He did so after the polls showed McCain scoring points with the "Drill, Baby Drill!" mantra. Did Obama really mean what he said? And now that gas is under $2.50 a gallon again for most Americans, do we still care?
Here are quick links to President-Elect Obama's campaign pledges on energy/global warming, environment, technology, and space. Feel free to hang on to these links to see how many campaign promises are broken or kept.
And let us know what you think.
–Peter Dykstra, Executive Producer, CNN Science, Technology & Weather
November 3, 2008
Posted: 11:02 AM ET
It seems rain DOES make a difference when deciding an election. As matter of fact it might have cost Al Gore the White House in 2000.
Election Day weather across the U.S. looks mostly dry - a good sign for Democrats?
According to Florida State University researcher Brad Gomez (along with Thomas G. Hansford and George A. Krause), just an inch of rain can make a big difference in a tight race. (Gomes, who recently joined the faculty at FSU, did his research while at the University of Georgia).
The researchers studied the past 14 presidential elections using simulated weather conditions for those dates based on data from more than 22,000 weather reporting stations. They found that while 1 inch of rain drops overall voter turnout by less than 1 percent, the Democratic turnout drops by 2.5 percent. There was significant rain in the Florida panhandle during the controversial 2000 election when George W. Bush beat Gore by just hundreds of votes in Florida to win the presidency. If it hadn’t rained, enough additional Democrats might have voted in Florida to give Gore the White House.
Other interesting findings in the study show that younger voters are less likely to vote in bad weather while older voters are more inclined to vote rain or shine. (Once again we need to follow the lead of our elders and vote - regardless of the weather!!!)
So where might weather play a role during Tuesday's voting? The weather map looks pretty simple: The battleground state of North Carolina, where both the presidential race and a U.S. Senate race are competitive, will see some rain along the coast. The rest of the eastern half of the country should be dry. Areas west of the continental divide will see some valley rain and mountain snow.
Does that mostly dry forecast bode well for Barack Obama and the Democrats this time? We'll soon find out.
Filed under: Weather
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