Science News
Discovery of 2.8-million-year-old jaw sheds light on early humans
Arizona State University
A fossil lower jaw found in the Ledi-Geraru research area, Afar Regional State, Ethiopia, pushes back evidence for the human genus -- Homo -- to 2.8 million years ago, according to a pair of reports published March 4 in the online version of the journal Science. The jaw predates the previously known fossils of the Homo lineage by approximately 400,000 years. It was discovered in 2013 by an international team led by Arizona State University scientists Kaye E. Reed, Christopher J. Campisano and J Ramón Arrowsmith, and Brian A. Villmoare of the University of Nevada, Las Vegas.
For decades, scientists have been searching for African fossils documenting the earliest phases of the Homo lineage, but specimens recovered from the critical time interval between 3 and 2.5 million years ago have been frustratingly few and often poorly preserved. As a result, there has been little agreement on the time of origin of the lineage that ultimately gave rise to modern humans. At 2.8 million years, the new Ledi-Geraru fossil provides clues to changes in the jaw and teeth in Homo only 200,000 years after the last known occurrence of Australopithecus afarensis ("Lucy") from the nearby Ethiopian site of Hadar.
|
'Extinct' bird rediscovered: Last seen in 1941
Wildlife Conservation Society
A scientific team from WCS, Myanmar's Nature and Wildlife Conservation Division -- MOECAF, and National University of Singapore (NUS) has rediscovered a bird previously thought to be extinct.
Jerdon's babbler (Chrysomma altirostre) had not been seen in Myanmar since July 1941, where it was last found in grasslands near the town of Myitkyo, Bago Region near the Sittaung River.
The rediscovery was described in the recently published issue of Birding Asia, the magazine of the Oriental Bird Club.
The team found the bird on 30 May 2014 while surveying a site around an abandoned agricultural station that still contained some grassland habitat. After hearing the bird's distinct call, the scientists played back a recording and were rewarded with the sighting of an adult Jerdon's babbler. Over the next 48 hours, the team repeatedly found Jerdon's babblers at several locations in the immediate vicinity and managed to obtain blood samples and high-quality photographs.
|
Technology News
Strength in numbers: First-ever quantum device that detects and corrects its own errors
University of California - Santa Barbara
When scientists develop a full quantum computer, the world of computing will undergo a revolution of sophistication, speed and energy efficiency that will make even our beefiest conventional machines seem like Stone Age clunkers by comparison.
But, before that happens, quantum physicists like the ones in UC Santa Barbara's physics professor John Martinis' lab will have to create circuitry that takes advantage of the marvelous computing prowess promised by the quantum bit ("qubit"), while compensating for its high vulnerability to environmentally-induced error.
In what they are calling a major milestone, the researchers in the Martinis Lab have developed quantum circuitry that self-checks for errors and suppresses them, preserving the qubits' state(s) and imbuing the system with the highly sought-after reliability that will prove foundational for the building of large-scale superconducting quantum computers.
|
The Most Logical (And Craziest) MH370 Conspiracy Theories
Jordan Golson
This weekend marks the one-year anniversary of the disappearance of Malaysia Airlines Flight 370. No physical evidence of the Boeing 777 has been found, and other clues—logs of automated satellite communications and from military radar—have delivered more questions than answers. The 239 passengers and crew on board are presumed dead, and the official stance on the fate of the plane is that it crashed—somewhere—into the Indian Ocean, for unknown reasons.
Flight 370 departed from Kuala Lumpur, Malaysia for Beijing, China early on March 8, 2014. It disappeared from air traffic control radar a few hours later, before popping up on a few military radar screens and finally disappearing over the Andaman Sea. A comprehensive search was undertaken across tens of thousands of square miles of ocean in a number of different regions, and the current search efforts are focused on the bottom of the Indian Ocean more than a thousand miles southwest of Perth, Australia.
|
Environmental News
Nutrient pollution damages streams in ways previously unknown, ecologists find
University of Georgia
An important food resource has been disappearing from streams without anyone noticing until now.
In a new study published March 6 in the journal Science, a team of researchers led by University of Georgia ecologists reports that nutrient pollution causes a significant loss of forest-derived carbon from stream ecosystems, reducing the ability of streams to support aquatic life.
The findings show that the in-stream residence time of carbon from leaves, twigs and other forest matter, which provide much of the energy that fuels stream food webs, is cut in half when moderate amounts of nitrogen and phosphorus are added to a stream.
"This study shows how excess nutrients reduce stream health in a way that was previously unknown," said the study's lead author Amy D. Rosemond, an associate professor in the UGA Odum School of Ecology.
|
El Niño Forms, but Forecasters See Little Weather Impact
By HENRY FOUNTAIN
Federal government scientists say that a long-anticipated El Niño weather pattern formed in the Pacific Ocean last month, but that it will most likely have little significant impact worldwide.
In an El Niño, prevailing winds slacken, allowing a buildup of warm water in the eastern Pacific that can disrupt high-atmosphere winds and other elements that affect weather. Researchers with the National Oceanic and Atmospheric Administration had suggested last year that an El Niño was likely but that it would probably be weak.
El Niño conditions can bring more rain to California, but the researchers said this one was so weak that even though it could last into summer, it would provide little or no relief for the state, which is in the throes of an extreme drought. However, they said, the Gulf Coast may experience more precipitation than normal this spring.
|
Medical News
Phthalates potentially alter levels of a pregnancy hormone that influences sex development
University of Pittsburgh Schools of the Health Sciences
Exposure to hormone-altering chemicals called phthalates -- which are found in many plastics, foods and personal care products -- early in pregnancy is associated with a disruption in an essential pregnancy hormone and adversely affects the masculinization of male genitals in the baby, according to research led by the University of Pittsburgh Graduate School of Public Health.
The findings, presented today at the Endocrine Society's 97th annual meeting in San Diego and funded by the National Institute of Environmental Health Sciences, focus on the role of the placenta in responding to these chemicals and altering levels of a key pregnancy hormone. These results suggest that there may be reason to push routine clinical testing earlier in pregnancy to check for the effects of chemicals and help guide potential interventions to protect the health of the baby.
"Phthalates are pervasive," said Jennifer Adibi, M.P.H., Sc.D., assistant professor of epidemiology at Pitt Public Health. "Reducing exposure to phthalates and other hormone-disrupting chemicals is something that needs to be addressed at a societal level through consumer advocacy and regulation, and education of health care providers."
|
Last Known Ebola Patient in Liberia Is Discharged
By NORIMITSU ONISHI
Liberia’s last Ebola patient was discharged on Thursday after a ceremony in the capital, Monrovia, bringing to zero the number of known cases in the country and marking a milestone in West Africa’s battle against the disease.
Officials in Monrovia, the city where the raging epidemic littered the streets with bodies only five months ago, celebrated even as they warned that Liberia was at least weeks away from being officially declared free of Ebola. They also noted that the disease had flared up recently in neighboring Sierra Leone and Guinea, the two other countries hardest hit by it.
“It was touching, it was pleasing,” Tolbert Nyenswah, the deputy health minister in charge of Liberia’s fight against Ebola, said in a telephone interview about the ceremony. “There was a lot of excitement because we feel that this is a victory.”
|
Space News
Mars: The planet that lost an ocean's worth of water
European Southern Observatory - ESO
A primitive ocean on Mars held more water than Earth’s Arctic Ocean, and covered a greater portion of the planet’s surface than the Atlantic Ocean does on Earth, according to new results published today. An international team of scientists used ESO’s Very Large Telescope, along with instruments at the W. M. Keck Observatory and the NASA Infrared Telescope Facility, to monitor the atmosphere of the planet and map out the properties of the water in different parts of Mars’s atmosphere over a six-year period. These new maps are the first of their kind.
The results appear online in the journal Science today.
About four billion years ago, the young planet would have had enough water to cover its entire surface in a liquid layer about 140 metres deep, but it is more likely that the liquid would have pooled to form an ocean occupying almost half of Mars's northern hemisphere, and in some regions reaching depths greater than 1.6 kilometres.
"Our study provides a solid estimate of how much water Mars once had, by determining how much water was lost to space," said Geronimo Villanueva, a scientist working at NASA's Goddard Space Flight Center in Greenbelt, Maryland, USA, and lead author of the new paper. "With this work, we can better understand the history of water on Mars."
|
Why isn't the universe as bright as it should be?
Massachusetts Institute of Technology
A handful of new stars are born each year in the Milky Way, while many more blink on across the universe. But astronomers have observed that galaxies should be churning out millions more stars, based on the amount of interstellar gas available.
Now researchers from MIT and Michigan State University have pieced together a theory describing how clusters of galaxies may regulate star formation. They describe their framework this week in the journal Nature.
When intracluster gas cools rapidly, it condenses, then collapses to form new stars. Scientists have long thought that something must be keeping the gas from cooling enough to generate more stars -- but exactly what has remained a mystery.
|
Odd News
How big is the average penis?
By David Shultz
“I was in the pool!” George Costanza’s distress at the “shrinkage” of his penis after exiting a cold pool was hilarious in the 1994 Seinfeld episode, but for many men concern over the length and girth of their reproductive organ is no laughing matter. Now, a new study could assuage such worries with what may be the most accurate penis-size measurements to date.
Many earlier studies relied on self-reporting, which doesn’t always yield reliable results. “People tend to overestimate themselves,” says David Veale, a psychiatrist at the South London and Maudsley NHS Foundation Trust. So when Veale and his team set out to settle the score on penile proportions, they decided to compile data from clinicians who followed a standardized measuring procedure.
Published today in the British Journal of Urology International, their new study synthesizes data from 17 previous academic papers that included measurements from a total of 15,521 men from around the world. The data enabled the researchers to calculate averages and model the estimated distribution of penile dimensions across humanity. “It still just strikes me how many men have questions and insecurities and concerns about their own penis size. We actually do need good data on it,” says Debra Herbenick, a behavioral scientist at Indiana University, Bloomington, who was not involved in the study.
|