An evolutionary "loophole" might explain why males of many species live shorter lives than their female counterparts, a new study finds.

The loophole lies in the mitochondria, the energy-generating parts of our cells. The mitochondria have their own DNA, separate from the DNA that resides in the nucleus of the cell that we usually think of when we think of the genome. In almost all species, the mitochondria DNA is passed down solely from mother to child, without input from dad.

This direct line of inheritance may allow harmful mutations to accumulate, according to a new study detailed today (Aug. 2) in the journal Current Biology. Ordinarily, natural selection helps keep harmful mutations to a minimum by ensuring they're not passed down to offspring. But if a mitochondrial DNA mutation is dangerous only to males and doesn't harm females, there's nothing to stop mom from passing it to her daughters and sons.

"If a mitochondrial mutation pops up that is benign in females, or a mutation pops up that is beneficial to females, this mutation will slip through the gates of natural selection and go through to the next generation," said study researcher Damian Dowling, an evolutionary biologist at Monash Univeristy in Australia.

The result: a load of mutations that don't harm females, but add up to a shorter life span for males.

Elephants' deepest calls can thunder up to 6 miles (10 kilometers) away. Now, researchers have learned for the first time how the massive animals produce these sounds.

It turns out that they do it in the same way that humans talk, pushing air through their vocal cords to make them vibrate. Elephants can go much lower than humans, however, because their vocal cords are eight times longer.

"The sounds the elephants make are off the piano keyboard," said study researcher Christian Herbst, a voice scientist at the University of Vienna, Austria. In fact, at less than 20 hertz in frequency, the main components of these ultra-deep calls aren't detectable to the human ear.

Until now, researchers weren't sure how elephants produced such low sounds. In fact, it's difficult to study voice production in animals in general, Herbst told LiveScience. In humans, researchers can insert cameras through the throat into the larynx, or voicebox, while people make different sounds. Animals tend to be less cooperative on that front, Herbst said.

There are two ways to produce sound by vibrating the vocal cords (or vocal folds, as scientists call them). The first is called active muscular contraction, or AMC. With this method, the throat muscles actively contract to vibrate the vocal folds. AMC is how cats purr.

The other method of sound production is called the myoelastic-aerodynamic (MEAD) mode. The MEAD mode uses air from the lungs to vibrate the vocal folds. MEAD is how humans talk and sing.

© USGSThis crack in the Earth was left by the 2004 Parkfield earthquake that ruptured along the San Andreas Fault.

Ambient noise monitored to see if cataclysmic events can be forecast at all

Forecasting earthquakes has long been an elusive goal for geoscientists, even along the San Andreas Fault, one of the most well-studied and active earthquake faults on Earth.

Detecting changes in the Earth's crust before a quake is one way to determine whether faults send out early warning signals, which could offer the possibility of short-term earthquake predictions.

One way to potentially detect these warning signals is using a process called ambient noise tomography. Vibrations from ocean waves and the wind make the Earth constantly hum. Scientists can tease out detailed images of the Earth's crust from the murmuring as the velocities of the vibrations change as they move through different rock types.

"The ambient noise in the Earth is just sound waves. It illuminates the structures in the Earth like ambient light illuminates a room," said seismologist David Schaff, a professor at Columbia University's Lamont Doherty Earth Observatory in New York.

The past decade has been plagued with what seems to be a cluster of large earthquakes, with massive quakes striking Sumatra, Chile, Haiti and Japan since 2004. Some researchers have suggested that this cluster has occurred because the earthquakes may be "communicating" across large distances, possibly triggering each other. But a new analysis by Tom Parsons and Eric Geist of the US Geological Survey concludes that the cluster could just as well be the result of random chance.

Each of the devastating quakes in the 2000s drew huge media coverage and required extensive rebuilding and economic restoration. The intense interest in the earthquakes has led some to wonder if we are living in the middle of an "age of great quakes," similar to a global cluster of quakes in the 1960s. It's important to know whether these clusters occur because big earthquakes trigger others across the world, Parsons and Geist say, in order to predict whether more severely destructive quakes might be on the way. To determine if the quake clusters in the 1960s and 2000s could be attributed to random chance, the researchers looked at the timing between the world's largest earthquakes--magnitude 8.3 and above--at one-year intervals during the past 100 years. They compared simulated lists of large quakes and the list of real quakes during this time with the between-quake intervals expected from a random process. The intervals between the real-life large quakes are similar to what would be expected from a random process, they found. In other words, the global hazard of large earthquakes is constant in time. Except in the case of local aftershocks, the probability of a new large quake occurring isn't related to past global quakes.

A NASA space telescope designed to hunt for black holes and other mysteries of the universe passed a key test in orbit last week, setting the stage for the X-ray observatory to begin its prime science-gathering mission, NASA says.

NASA's Nuclear Spectroscopic Telescope Array, or NuSTAR for short, passed a post-launch review of its hardware, instruments and calibration in orbit last week. The observatory will begin gathering science data for its main science operations phase in August, NASA officials said in a statement.

NuSTAR is designed to observe high-energy, short-wavelength X-ray light from some of the most dynamic objects in space, including black holes and supernova remnants.

The observatory was launched into space June 13 from near the Kwajalein Atoll in the South Pacific. Roughly a week later, NuSTAR stretched out its massive 33-foot (10-meter) mast, which separates its two X-ray light-gathering optics from a point where the light will be focused and collected by a camera.

The post-launch assessment, conducted at NASA's Jet Propulsion Laboratory in Pasadena, Calif., included a full checkout of the spacecraft and its deployed mast.

Riverside, California - For millennia, humans have pondered their mortality and whether death is the end of existence or a gateway to an afterlife. Millions of Americans have reported near-death or out-of-body experiences. And adherents of the world's major religions believe in an afterlife, from reincarnation to resurrection and immortality.

Anecdotal reports of glimpses of an afterlife abound, but there has been no comprehensive and rigorous, scientific study of global reports about near-death and other experiences, or of how belief in immortality influences human behavior. That will change with the award of a three-year, $5 million grant by the John Templeton Foundation to John Martin Fischer, distinguished professor of philosophy at the University of California, Riverside, to undertake a rigorous examination of a wide range of issues related to immortality. It is the largest grant ever awarded to a humanities professor at UC Riverside, and one of the largest given to an individual at the university.

"People have been thinking about immortality throughout history. We have a deep human need to figure out what happens to us after death," said Fischer, the principal investigator of The Immortality Project. "Much of the discussion has been in literature, especially in fantasy and science fiction, and in theology in the context of an afterlife, heaven, hell, purgatory and karma. No one has taken a comprehensive and sustained look at immortality that brings together the science, theology and philosophy."

The John Templeton Foundation, located near Philadelphia, supports research on subjects ranging from complexity, evolution and infinity to creativity, forgiveness, love, and free will.

Half of the $5 million grant will be awarded for research projects. The grant will also fund two conferences, the first of which will be held at the end of the project's second year and the second at the end of the grant period. A website will include a variety of resources, from glossaries and bibliographies to announcements of research conferences and links to published research. Some recent work in Anglo-American philosophy will be translated for German philosophers who, in the last 30 years, have been increasingly studying the work of American philosophers.

A study on possible effects of the 2010 BP oil spill indicates dispersants may have killed plankton - some of the ocean's tiniest plants and creatures - and disrupted the food chain in the Gulf of Mexico, one of the nation's richest seafood grounds.

Scientists who read the study said it points toward major future effects of the spill. One called its findings scary.

For the study, Alabama researchers pumped water from Mobile Bay into 53-gallon drums, then added oil, dispersant or both in proportions found during the oil spill to simulate the spill's effects on microscopic water-life in the bay.

Over more than 12 weeks in 2010, BP's well spewed nearly 200 million gallons of oil into the Gulf of Mexico. The company used more than 1.8 million gallons of dispersants - more than 770,000 gallons of it at the oil's source on the ocean floor - to break up the oil into tiny droplets. Earlier research hadn't found significant problems for the environment and marine life, but dispersants had never before been used a mile underwater or in such large amounts.

A robot baby being built as part of a neuroscience research program in Japan has just gotten a torso, including arms that flop around like an infant's sans swaddle.

Affeto, the robo-baby, is creepy in its realism, which is what the team from Osaka University aims to accomplish as they use robotics to study "how humans' higher cognitive functions develop," according to a project description.

Ultimately, the robot will be used in behavioral experiments. For now, the researchers are trying to "build a realistic child robot with a muscle-skeletal system."

The torso's flexibility comes from 22 pneumatic actuators in its body.

In the video below you can see that Affeto's torso is approaching the realistic stage. At one point, it hits itself in the face with "babyish looseness."

Rabies has been thought of as virtually 100-percent fatal unless treated immediately, but new research shows that a small number of isolated Peruvians have natural immunity from the animal-transmitted disease.

Researchers at the Centers for Disease Control and Prevention found that one in 15 people living in the remote Amazonian region in Peru were protected without medical intervention against the virus that kills more than 55,000 people globally every year.

Their trick: Vampire bats exposed the remote Peruvians to enough of the rabies virus to confer resistance, but not enough to kill them.

"Our results open the door to the idea that there may be some type of natural resistance or enhanced immune response in certain communities regularly exposed to the disease," Amy Gilbert, a researcher with the CDC's National Center for Emerging and Zoonotic Infectious Diseases and co-lead study author, said in a statement.

"This means there may be ways to develop effective treatments that can save lives in areas where rabies remains a persistent cause of death."

The first case of skin cancer in a wild marine fish population looks eerily similar to the melanoma that plagues humans, researchers report today (Aug. 1).

Coral trout living on Australia's Great Barrier Reef are directly beneath the Antarctic ozone hole, the world's largest, which is the result of the depletion of ozone in the atmosphere that normally protects humans from harmful UV rays.

"Further work needs to be carried out to establish the exact cause of the cancer, but having eliminated other likely factors such as microbial pathogens and marine pollution, UV radiation appears to be the likely cause," study researcher Michael Sweet, of Newcastle University in the United Kingdom, said in a statement.

Sweet and his colleagues examined 136 common coral trout (Plectropomus leopardus), and found 20 individuals, or 15 percent, showed dark skin lesions.

The lesions ranged in size from small (covering just 5 percent of the skin) to large, covering the fish's full body, they report online in the journal PLoS ONE.