Science

Cat Domestication Traced to Chinese Farmers 5,300 Years Ago

Five-thousand years before it was immortalized in a British nursery rhyme, the cat that caught the rat that ate the malt was doing just fine living alongside farmers in the ancient Chinese village of Quanhucun, a forthcoming study in the Proceedings of the National Academy of Sciences has confirmed.
Results of the study show that the village of Quanhucun was a source of food for the cats 5,300 years ago, and the relationship between humans and cats was commensal, or advantageous for the cats. The evidence for this study is derived from research in China led by Yaowu Hu.  Using radiocarbon dating and isotopic analyses of carbon and nitrogen traces in the bones of cats, dogs, deer and other wildlife unearthed near Quanhucan, the research team demonstrated how a breed of once-wild cats carved a niche for themselves in a society that thrived on the widespread cultivation of the grain millet.
Recent DNA studies suggest that most of the estimated 600 million domestic cats now living around the globe are descendants most directly of the Near Eastern Wildcat, one of the five Felis sylvestris lybica wildcat subspecies still found around the Old World. 

Music Brings Memories Back to the Injured Brain

In the first study of its kind, two researchers have used popular music to help severely brain-injured patients recall personal memories. Amee Baird and Séverine Samson outline the results and conclusions of their pioneering research in the recent issue of the journal Neuropsychological Rehabilitation.
Although their study covered a small number of cases, it's the very first to examine 'music-evoked autobiographical memories' (MEAMs) in patients with acquired brain injuries (ABIs), rather than those who are healthy or suffer from Alzheimer's disease.
In their study, Baird and Samson played extracts from 'Billboard Hot 100' number-one songs in random order to five patients. The songs, taken from the whole of the patient's lifespan from age five, were also played to five control subjects with no brain injury. All were asked to record how familiar they were with a given song, whether they liked it, and what memories it invoked.
Doctors Baird and Samson found that the frequency of recorded MEAMs was similar for patients (38%-71%) and controls (48%-71%). Only one of the four ABI patients recorded no MEAMs. In fact, the highest number of MEAMs in the whole group was recorded by one of the ABI patients. In all those studied, the majority of MEAMs were of a person, people or a life period and were typically positive. Songs that evoked a memory were noted as more familiar and more liked than those that did not.
The authors hope that further studies of both healthy people and those with other neurological conditions to learn more about the clear relationship between memory, music and emotion; they hope that one day we might truly "understand the mechanisms underlying the unique memory enhancing effect of music."

Mothers See Their Youngest as Shorter Than They Are

Many parents say when their second child is born that their first child suddenly appears to have grown overnight. Now, researchers reporting in the Cell Press journal Current Biology on December 16 have an explanation: until the birth of the new child, those parents were subject to a "baby illusion," routinely misperceiving their youngest child as smaller (and younger) than he or she really was.
Researchers at Swinburne University of Technology in Australia made the discovery first by asking 747 mothers if they remembered experiencing a sudden shift in their first child's size after the birth of a new infant. The researchers found that 70% of the mothers did.
To further explore that perceptual shift, the researchers asked mothers to estimate the height of one of their young children (aged 2 to 6) by marking a blank wall. When the researchers compared those height estimations to the child's real height, they found something very interesting: mothers significantly underestimated the height of their youngest child by 7.5 cm on average. In contrast, height estimates for the eldest child were almost accurate.
The findings are a useful reminder of just how filtered our own perceptions of the world around us can be. Researchers concluded that in many cases, we cannot rust the accuracy of our perceptions. 

Inkblots Improve Security of Online Passwords

The GOTCHA password system developed at Carnegie Mellon University incorporates randomly generated inkblots (Courtesy: Carnegie Mellon University)

Carnegie Mellon University computer scientists have developed a new password system that incorporates inkblots to provide an extra measure of protection when, as so often occurs, lists of passwords get stolen from websites.
This new type of password, dubbed a GOTCHA (Generating panOptic Turing Tests to Tell Computers and Humans Apart), would be suitable for protecting high-value accounts, such as bank accounts, medical records and other sensitive information.
To create a GOTCHA, a user chooses a password and a computer then generates several random, multi-colored inkblots. The user describes each inkblot with a text phrase. These phrases are then stored in a random order along with the password. When the user returns to the site and signs in with the password, the inkblots are displayed again along with the list of descriptive phrases; the user then matches each phrase with the appropriate inkblot.
These puzzles would prove significant when security breaches of websites result in the loss of millions of user passwords -- a common occurrence that has plagued such companies as LinkedIn, Sony and Gawker. These passwords are stored as cryptographic hash functions, in which passwords of any length are converted into strings of bits of uniform length. A thief can't readily decipher these hashes, but can mount what's called an automated offline dictionary attack. Computers today can evaluate as many as 250 million possible hash values every second.