Shards of pottery with traces of mare's milk, mass gravesites for horses, and drawings of horses with plows and chariots: These are some of the signs left by ancient people hinting at the importance of horses to their lives. But putting a place and date on the domestication of horses has been a challenge for archaeologists. Now, a team of geneticists studying modern breeds of the animal has assembled an evolutionary picture of its storied past.

Horses, the scientists conclude, were first domesticated 6000 years ago in the western part of the Eurasian Steppe, modern-day Ukraine and West Kazakhstan. And as the animals were domesticated, they were regularly interbred with wild horses, the researchers say.

"This is a very good paper," says biologist Michael Hofreiter of the University of York in the United Kingdom. "Nobody has applied this method of population modeling to horses before."

Throughout their history, horses have been interbred, traded between populations of people, and moved across continents. All of this makes their genetic history hard to follow. Moreover, the wild ancestor of horses, Equus ferus, is extinct, complicating researchers' efforts to compare the genetics of domestic animals with wild ones. Previous research nailed down a broad area - the Eurasian Steppe, which stretches from Hungary and Romania through Mongolia - as the region where horses originated and were domesticated. But earlier genetic studies relied mostly on mitochondrial DNA, which is inherited only from a mother, to try to understand horses' evolutionary history.

A new analysis of an old human ancestor fossil indicates that human brains started growing 2.5 million years ago, about the time humans started walking upright.

An unfused seam on the fossil's head indicates the skull was still pliable for several years after birth, giving the brain time to grow. An imprint of the brain on the inside of the skull also gave researchers a good view of the developing human brain.

"These findings are significant because they provide a highly plausible explanation as to why the hominin brain might grow larger and more complex," study researcher Dean Falk, of Florida State University, said in a statement. When humans started walking upright, it put pressure on infant skulls to stay flexible, allowing them to continue to grow for several years, the researchers suggest.

Small bones

Belonging to a 3- to 4-year-old Australopithecus africanus, nicknamed "Taung Child," the fossil skull was discovered in 1924 and dates back to about 2.5 million years ago. The specimen was initially discovered in a lime mine in South Africa, and was the first specimen of this species of hominin.

The researchers used three-dimensional scans to analyze the skull, which includes most of the face, jaw and teeth, as well as a natural internal cast of the braincase; they also compared their results with other hominid skulls, including those of chimpanzees and bonobos.

Such scans allowed the researchers to determine that the joints between the child's skull plates (called the metopic suture) hadn't fully fused, a uniquely human trait.

One of the largest sunspot groups in years rotated over the sun's northeastern limb this weekend. With a least four dark cores larger than Earth, AR1476 sprawls more than 100,000 km from end to end, and makes an easy target for backyard solar telescopes. Amateur astronomer Alan Friedman sends this picture of the behemoth from his backyard in Buffalo, NY:
"AR1476 is firecrackler," says Friedman. Indeed, the active region is crackling with impulsive M-class solar flares. Based on the sunspot's complex 'beta-gamma' magnetic field, NOAA forecasters estimate a 70% chance of more M-flares during the next 24 hours. There is also a 5% chance of powerful X-flares.

"This one is going to be fun as turns to face us!" predicts Friedman. He might be right.

Fido's expressive face, including those longing puppy-dog eyes, may lead owners to wonder what exactly is going on in that doggy's head. Scientists decided to find out, using brain scans to explore the minds of our canine friends.

The researchers, who detailed their findings May 2 in the open-access journal PLoS ONE, were interested in understanding the human-dog relationship from the four-legged perspective.

"When we saw those first [brain] images, it was unlike anything else," said lead researcher Gregory Berns in a video interview posted online. "Nobody, as far as I know, had ever captured images of a dog's brain that wasn't sedated.

This was [a] fully awake, unrestrained dog, here we have a picture for the first time ever of her brain," added Berns, who is director of the Emory University Center for Neuropolicy.

He added, "Now we can really begin to understand what dogs are thinking. We hope this opens a whole new door into canine cognition, social cognition of other species."

Legal and technology researchers estimate that it would take about a month for Internet users to read the privacy policies of all the Web sites they visit in a year. So in the interest of time, here is the deal: You know that dream where you suddenly realize you're stark naked? You're living it whenever you open your browser.

There are no secrets online. That emotional e-mail you sent to your ex, the illness you searched for in a fit of hypochondria, those hours spent watching kitten videos (you can take that as a euphemism if the kitten fits) - can all be gathered to create a defining profile of you.

Your information can then be stored, analyzed, indexed and sold as a commodity to data brokers who in turn might sell it to advertisers, employers, health insurers or credit rating agencies.

And while it's probably impossible to cloak your online activities fully, you can take steps to do the technological equivalent of throwing on a pair of boxers and a T-shirt. Some of these measures are quite easy and many are free. Of course, the more effort and money you expend, the more concealed you are. The trick is to find the right balance between cost, convenience and privacy.

Before you can thwart the snoopers, you have to know who they are. There are hackers hanging around Wi-Fi hot spots, to be sure. But security experts and privacy advocates said more worrisome were Internet service providers, search engine operators, e-mail suppliers and Web site administrators - particularly if a single entity acts in more than one capacity, like Google, Yahoo, Facebook and AOL. This means they can easily collect and cross-reference your data, that is, match your e-mails with your browsing history, as well as figure out your location and identify all the devices you use to connect to the Internet.

Threats range from governments trying to control citizens to the rise of Facebook and Apple-style 'walled gardens'

The principles of openness and universal access that underpinned the creation of the internet three decades ago are under greater threat than ever, according to Google co-founder Sergey Brin.

In an interview with the Guardian, Brin warned there were "very powerful forces that have lined up against the open internet on all sides and around the world". "I am more worried than I have been in the past," he said. "It's scary."

The threat to the freedom of the internet comes, he claims, from a combination of governments increasingly trying to control access and communication by their citizens, the entertainment industry's attempts to crack down on piracy, and the rise of "restrictive" walled gardens such as Facebook and Apple, which tightly control what software can be released on their platforms.

Are we governed by unconscious processes? Neuroscience believes so - but isn't the human condition more complicated than that? Two experts offer different views

David Eagleman, neuroscientist at Baylor College of Medicine in Texas and bestselling author

It is clear at this point that we are irrevocably tied to the 3lb of strange computational material found within our skulls. The brain is utterly alien to us, and yet our personalities, hopes, fears and aspirations all depend on the integrity of this biological tissue. How do we know this? Because when the brain changes, we change. Our personality, decision-making, risk-aversion, the capacity to see colours or name animals - all these can change, in very specific ways, when the brain is altered by tumours, strokes, drugs, disease or trauma. As much as we like to think about the body and mind living separate existences, the mental is not separable from the physical.

This clarifies some aspects of our existence while deepening the mystery and the awe of others.

For example, take the vast, unconscious, automated processes that run under the hood of conscious awareness. We have discovered that the large majority of the brain's activity takes place at this low level: the conscious part - the "me" that flickers to life when you wake up in the morning - is only a tiny bit of the operations. This understanding has given us a better understanding of the complex multiplicity that makes a person. A person is not a single entity of a single mind: a human is built of several parts, all of which compete to steer the ship of state. As a consequence, people are nuanced, complicated, contradictory. We act in ways that are sometimes difficult to detect by simple introspection. To know ourselves increasingly requires careful studies of the neural substrate of which we are composed.

A 25-year-old San Francisco laboratory researcher was killed last week after contracting the deadly bacteria strain which he had been studying, various media outlets have reported.

According to Victoria Colliver of the San Francisco Chronicle, the man, who was identified by officials at the medical examiner's office as Richard Din, was employed at the Northern California Institute for Research and Education (NCIRE), a nonprofit dedicated to advancing veterans' health research at the VA hospital, for the past six months.

Colliver reports that he died at that facility just 17 hours after falling ill due to a bloodstream infection caused by Neisseria meningitidis, a rare strain of bacterium which has been known to cause blood infections and meningitis. She reports that he had been handling the bacterium for "several weeks" prior to his passing, and that while it was "unlikely" that the infection came from a different source, the cause of death was still under investigation.

Researchers in Spain have found that at least some of the individuals claiming to see the so-called aura of people actually have the neuropsychological phenomenon known as "synesthesia" (specifically, "emotional synesthesia"). This might be a scientific explanation of their alleged ability.

In synesthetes, the brain regions responsible for the processing of each type of sensory stimuli are intensely interconnected. Synesthetes can see or taste a sound, feel a taste, or associate people or letters with a particular color.

The study was conducted by the University of Granada Department of Experimental Psychology Óscar Iborra, Luis Pastor and Emilio Gómez Milán, and has been published in the journal Consciousness and Cognition.

This is the first time that a scientific explanation has been provided for the esoteric phenomenon of the aura, a supposed energy field of luminous radiation surrounding a person as a halo, which is imperceptible to most human beings.

In basic neurological terms, synesthesia is thought to be due to cross-wiring in the brain of some people (synesthetes); in other words, synesthetes present more synaptic connections than "normal" people.

"These extra connections cause them to automatically establish associations between brain areas that are not normally interconnected," professor Gómez Milán explains. New research suggests that many healers claiming to see the aura of people might have this condition.

A stream of highly charged particles from the sun is headed straight toward Earth, threatening to plunge cities around the world into darkness and bring the global economy screeching to a halt.

This isn't the premise of the latest doomsday thriller. Massive solar storms have happened before - and another one is likely to occur soon, according to Mike Hapgood, a space weather scientist at the Rutherford Appleton Laboratory near Oxford, England.

Much of the planet's electronic equipment, as well as orbiting satellites, have been built to withstand these periodic geomagnetic storms. But the world is still not prepared for a truly damaging solar storm, Hapgood argues in a recent commentary published in the journal Nature.

Hapgood talked with The Times about the potential effects of such a storm and how the world should prepare for it.

What exactly is a solar storm?

I find that's hard to answer. The term "solar storm" has crept into our usage, but nobody has defined what it means. Whether a "solar storm" is happening on the sun or is referring to the effect on the Earth depends on who's talking.

I prefer "space weather," because it focuses our attention on the phenomena in space that travel from the sun to the Earth.

People often talk about solar flares and solar storms in the same breath. What's the difference?

Solar flares mainly emit X-rays - we also get radio waves from these things, and white light in the brightest of flares. They all travel at the same speed as light, so it takes eight minutes to arrive. There are some effects from flares, such as radio interference from the radio bursts.

But that's a pretty small-beer thing. The big thing is the geomagnetic storms [on Earth] that affect the power grid, and that's caused by the coronal mass ejections [from the sun].

Coronal mass ejections are caused when the magnetic field in the sun's atmosphere gets disrupted and then the plasma, the sun's hot ionized gas, erupts and send charged particles into space. Think of it like a hurricane - is it headed toward us or not headed toward us? If we're lucky, it misses us.