Dwindling Florida panthers get help
FREDERICK, Md., Sept. 23 (UPI) -- The population of endangered Florida panthers has tripled, thanks largely to a genetic infusion courtesy of the animals' Texas cousins, wildlife experts say.
Hybrids of the Florida cats and cousins of the same species from a wild-caught Texas population have twice the genetic variety and far fewer of the genetic defects that were known in Floridian panthers before the introduction of the cats from Texas, ScienceNews.org reported.
Thanks to the genetic infusion and other conservation measures, the adult panther population in Florida has tripled, geneticist Warren Johnson of the National Cancer Institute in Fredrick, Md., says.
Now panthers of mixed-state background live about twice as long as the pure Floridians do, researchers say.
Wildlife managers now put adult panther numbers in the 90s, sometimes pushing into three digits during a banner year.
"This work can be a good model for other severely depleted populations of carnivores," cat conservation biologist Howard Quigley, based in Bozeman, Mont., said.
But Florida's panthers are far from safe, scientists say.
A troubling question is whether Florida can provide enough habitats for a population to survive. A mere hundred Florida panthers do not make a viable population in the long term.
"The Florida panther represents the increasing reality for many large carnivores in the world.
Groundwater depletion rate said doubled
WASHINGTON, Sept. 23 (UPI) -- The rate at which humans are drawing from vast underground stores of groundwater on which billions rely has doubled in recent decades, a Dutch researcher says.
Findings published in the journal Geophysical Research Letters say water is rapidly being pulled from fast-shrinking subterranean reservoirs essential to daily life and agriculture in many regions.
So much water is being drawn from below ground that its evaporation and eventual precipitation accounts for about 25 percent of the annual sea level rise across the planet, the researchers said.
Global groundwater depletion threatens potential disaster for an increasingly globalized agricultural system, Marc Bierkens of Utrecht University in Utrecht, the Netherlands, said.
"If you let the population grow by extending the irrigated areas using groundwater that is not being recharged, then you will run into a wall at a certain point in time, and you will have hunger and social unrest to go with it," Bierkens says. "That is something that you can see coming for miles."
The researchers say the rate at which global groundwater stocks are shrinking has more than doubled between 1960 and 2000, increasing the amount lost from 30 cubic miles to 68 cubic miles per year.
Because the total amount of the world's groundwater is unknown it's hard to estimate how fast the global supply would vanish at this rate, but if water was drained as rapidly from the Great Lakes they would go bone-dry in around 80 years, scientists say.
Study: Cities 'evolved' disease resistance
LONDON, Sept. 23 (UPI) -- A genetic variant that protects against diseases such as tuberculosis is more prevalent in populations with long histories of city living, scientists say.
University College London researchers have found that in areas with a long history of urban settlements, today's inhabitants are more likely to possess the genetic variant that provides resistance to infection, a university release said.
In ancient cities, poor sanitation and high population densities would have provided an ideal breeding ground for the spread of disease.
Natural selection should mean humans would have developed resistance to disease in longstanding urbanized populations over time.
UCL researchers tested the theory by analyzing DNA samples from 17 different human populations living across Europe, Asia and Africa.
Past exposure to pathogens in urban environments led to disease resistance spreading through populations, with ancestors passing their gene variant resistance to their descendants, they say.
"The results show that the protective variant is found in nearly everyone from the Middle East to India and in parts of Europe where cities have been around for thousands of years" UCL Professor Mark Thomas says.
It's a perfect example of human evolution, another researcher says.
"This seems to be an elegant example of evolution in action," biologist Ian Barns says. "It flags up the importance of a very recent aspect of our evolution as a species, the development of cities as a selective force.
"It could also help to explain some of the differences we observe in disease resistance around the world," Barnes said.
China keeps up busy space launch schedule
BEIJING, Sept. 23 (UPI) -- In the latest effort in China's feverish pace of space exploration activities, it has successfully launched a secret military payload, authorities said.
It was the fifth launch in less than two months for China and the second launching in that time period of a clandestine Yaogan reconnaissance satellite, SPACE.com reported Thursday.
China's recent rush to space includes a mysterious orbital rendezvous, an upcoming lunar probe and preparations for continued human missions.
Wednesday's blastoff of a Long March 2D rocket from the Jiuquan space center in the desert of northwestern China placed Yaogan 11 and two smaller satellites on a path nearly 400 miles above Earth.
The Yaogan 11 will conduct scientific experiments, survey land resources, estimate crop yields and contribute to natural disaster response efforts, the state-run Xinhua news agency reported.
The Yaogan satellites are believed to provide the Chinese military with high-resolution reconnaissance imagery, experts say.
Next year, China plans to send its Tiangong 1 module to space.
A series of unmanned and manned Shenzhou capsules will visit the module, forming a modest space station for long-duration research missions by Chinese astronauts, SPACE.com said.
