WEAKNESS IN NUMBERS 

Earth's human population will reach 7 billion later this year, according to a new report based on U.N. data, with the 7 billionth person expected to be born in India sometime around Oct. 31. This population boom is heavily concentrated in developing nations such as India, China and Brazil, the report notes, due partly to new vaccines, antibiotics and other public-health gains that have increased life expectancy. But despite such benefits, the surging number of humans on Earth may be undermining their own success, experts warn, by outpacing the planet's ability to sustain them.

"Every billion people we add to the planet makes life more difficult for everyone and will do more damage to the environment," John Bongaarts, a demographer at the New York-based Population Council, tells Discovery News. "Can we support 10 billion people? Probably. But we would all be better off with a smaller population." Humanity reached the 1 billion mark in 1800 — fueled by the fledgling Industrial Revolution — and hasn't looked back since. There were 2 billion of us by 1925, and the global population grew by 293 percent during the 20th century, compared with an average of 22 percent each of the previous nine centuries. The number had ballooned to 6 billion by 1999, and now it's poised to hit 7 billion just 12 years later. According to the new study, published in the journal Science, another 2.3 billion people will be added by 2050, and there will be more than 10 billion humans on Earth at the end of the century.

Population growth isn't occurring evenly around the world, though, with researchers forecasting the planet's "demographic center of gravity" will shift from developed to developing regions. About 97 percent of the next 2.3 billion people will live in developing countries, according to the study, with nearly half of them in Africa. "The demographic picture is indeed complex, and poses some formidable challenges," says David Bloom, a Harvard University economist and lead author of the study. "Those challenges are not insurmountable, but we cannot deal with them by sticking our heads in the sand. ... It's just plain irresponsible to sit by idly while humankind experiences full force the perils of demographic change."

(Sources: CNN, UPI, Discovery News, Bloomberg News, ScienceDaily)

CARS 2 

Within the next 15 years, the average American car should be twice as fuel-efficient as it is today, according to a historic deal between automakers and the Obama administration. Under the new plan, unveiled Friday by President Obama Friday, U.S. vehicles must meet a fuel-economy standard of 54.5 miles per gallon by 2025, up from the current 27 mpg. As the New York Times reports, that's the largest increase in U.S. mileage rules since federal regulation of fuel consumption began in the 1970s.

Automakers have vigorously fought such regulations for decades — arguing they would make cars too small and expensive, and even cost jobs — but their bargaining position was eroded by the economic crisis of 2008 and government bailouts of General Motors and Chrysler. Reluctant to attack an administration that saved their industry from collapse just a few years ago, executives from major U.S. automakers have embraced the new efficiency standards, marking an "extraordinary shift in the relationship between the companies and Washington," as the Times puts it. But their recent economic humbling isn't the only reason — automakers have also become more adept at building popular small cars that use gasoline more efficiently, and six of the 10 best-selling vehicles in the U.S. are now small or midsize cars. "This was no time to fight these regulations," one unidentified Detroit auto executive tells the Times. "And you're starting to see these fundamental shifts in the market that play a huge role in this."

Since the new requirements should reduce oil consumption and therefore curb emissions of carbon dioxide, many environmental groups are heralding the deal as a milestone. "The auto companies' level of vitriol and rhetoric has changed," Dan Becker of the Safe Climate Campaign tells the Times. "We welcome all epiphanies." Still, it's a step down from the 62 mpg standard the White House originally sought, and some experts say it could be further watered down along the way. "This seems to be how the game is played — they put a big fuel economy number out there and then introduce loopholes," Jeremy Anwyl, CEO of Edmunds.com, tells Bloomberg News. "They want to try to keep everyone happy."

(Sources: New York Times, Detroit Free Press, Bloomberg News, CNET)

COLD SHOULDER 

A government scientist known for studying how melting sea ice affects polar bears has been placed on administrative leave, the Alaska Dispatch reports, while officials at the U.S. Bureau of Ocean Energy Management, Regulation and Enforcement investigate "integrity issues" possibly related to his research. Wildlife biologist Charles Monnett was suspended with pay on July 18, and barred from contacting any of his colleagues or even entering any offices of the U.S. Interior Department.

The manner and timing of Monnett's suspension has led to accusations the move is politically motivated, the Dispatch reports. The research in question, an article about drowned polar bears that Monnett and a colleague saw, is from 2006, and was an "observational note" published in an obscure journal, not a peer-reviewed study. It's odd for the issue to be raised five years later, Monnett's supporters say, except that Shell Oil and other companies are currently seeking permits from BOEMRE to drill in the Arctic next summer — permits that could theoretically be easier for BOEMRE to approve if research like Monnett's is discredited. "You have to wonder: This is the guy in charge of all the science in the Arctic and he is being suspended just now as an arm of the Interior Department is getting ready to make its decision on [skipwords]offshore drilling[/skipwords] in the Arctic seas," says Jeff Ruch, president of Public Employees for Environmental Responsibility. "This is a cautionary tale with a deeply chilling message for any federal scientist who dares to publish groundbreaking research on conditions in the Arctic."

Ruch's group filed an official complaint Thursday on Monnett's behalf, accusing federal officials of interfering with his research and trying to intimidate him. It seeks for Monnett to be reinstated, and to be issued an apology, but a spokeswoman for BOEMRE tells the Guardian that the investigation will be objective and untainted by political motives. "All of the scientific contracts previously managed by Mr. Monnett are being managed by the highly qualified scientists at BOEMRE," says agency spokeswoman Melissa Schwartz, adding that the review is being led by the inspector general, who is independent.

(Sources: Alaska Dispatch, New York Times, Associated Press, Guardian)

FINS DE SEMANA 

[skipwords]"Shark Week," the Discovery Channel's famous week of shark-centric programming that began back in 1986, will launch into its 24th year this weekend. The event has snowballed into a cultural tradition in the U.S., making sharks "the Betty Whites of the water," according to Entertainment Weekly. Shark Week 2011 kicks off Sunday night, starting with "Great White Invasion" at 9 and "Jaws Comes Home" at 10.

2011 has already been a big year for sharks, even without Shark Week to buoy their popularity. Taiwan, Chile, Fiji and the Bahamas have all passed or proposed laws to ban or restrict shark finning this year, following a recent example set by Palau, the Maldives and Honduras. The process of shark finning — in which the ancient fish are caught only for their fins, considered a delicacy in China — has decimated global shark populations, with up to 73 million of the animals reportedly killed around the world every year for their fins. This has caused some populations to fall by nearly 90 percent, and combined with other changes occurring in the Earth's seas, including ocean acidification and rising temperatures that are destabilizing the marine food web, experts say many shark species are in danger of dying off within decades. To help address this problem, Shark Week has begun to focus on shark conservation as well as sensationalism.

Still, Shark Week is ultimately about ratings, so the Discovery Channel isn't exactly making it into an academic pursuit. Hosted by Andy Samberg of "Saturday Night Live," the week includes a variety of shows like "Rogue Sharks," "Killer Sharks" and "10 Deadliest Sharks" that perhaps overemphasize the animals' threat to humans. But other shows like "Shark City" and "Jaws of the Pacific" examine the science of sharks, and the Shark Week website also includes a section, sponsored by Oceana and the Pew Charitable Trusts, that's dedicated to shark conservation.[/skipwords]

(Sources: Entertainment Weekly, USA Today, Discovery Channel)

THIS DAY IN HISTORY

The U.N. International Atomic Energy Agency is founded, Moscow suffers a record heat wave, and more.

Russell McLendon

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Photo (Earth's city lights seen from space): NASA

Photo (car's fuel gauge): U.S. Energy Department

Photo (polar bear on sea ice): NASA Earth Observatory

Photo (jumping great white shark): ZUMA Press

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