ScienceDaily: Top Science News

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• Oldest existing lizard-like fossil hints at scaly origins
• Genetic study pushes back timeline for first significant human population expansion
• Neurological basis for lack of empathy in psychopaths
• How stress can rewire brain making benign smells malodorous
• Late Cretaceous Period was likely ice-free
• Astronomers discover densest galaxy ever
• Chemists slide a splitting catalyst over DNA for first time
• Develop after-sex contraceptive pill for routine use, urge researchers: Political opposition biggest hurdle
• Caffeine consumption slows down brain development, rat study shows
• The dragon awakens: Colossal explosion from supermassive black hole at centre of galaxy revealed
• Brain may rely on computer-like mechanism to make sense of novel situations

Oldest existing lizard-like fossil hints at scaly origins Posted: 24 Sep 2013 04:36 PM PDT The fossilized remains of a reptile closely related to lizards are the oldest yet to be discovered. Two new fossil jaws discovered in Vellberg, Germany provide the first direct evidence that the ancestors of lizards, snakes and tuatara (known collectively as lepidosaurs), were alive during the Middle Triassic period -- around 240 million years ago.

Genetic study pushes back timeline for first significant human population expansion Posted: 24 Sep 2013 02:43 PM PDT Using new genetic tools, the authors conclude that the first significant expansion of human populations appears to be much older than the emergence of farming and herding, dating back to the Paleolithic (60,000-80,000 years ago) rather than Neolithic age (10,000 years ago). They also suggest that strong Paleolithic expansions may have favored the emergence of sedentary farming in some populations during the Neolithic.

Neurological basis for lack of empathy in psychopaths Posted: 24 Sep 2013 02:43 PM PDT When individuals with psychopathy imagine others in pain, brain areas necessary for feeling empathy and concern for others fail to become active and be connected to other important regions involved in affective processing and decision-making, reports a new study.

How stress can rewire brain making benign smells malodorous Posted: 24 Sep 2013 02:41 PM PDT In evolutionary terms, smell is among the oldest of the senses. New research shows how anxiety or stress can rewire the brain, linking centers of emotion and olfactory processing, to make typically benign smells malodorous.

Late Cretaceous Period was likely ice-free Posted: 24 Sep 2013 12:39 PM PDT For years, scientists have thought that a continental ice sheet formed during the Late Cretaceous Period more than 90 million years ago when the climate was much warmer than it is today. Now, researchers have found evidence suggesting that no ice sheet formed at this time. This finding could help environmentalists and scientists predict what Earth's climate will be as carbon dioxide levels continue to rise.

Astronomers discover densest galaxy ever Posted: 24 Sep 2013 11:17 AM PDT Imagine the distance between the sun and the star nearest to it -- a star called Alpha Centauri. That's a distance of about four light years. Now, imagine as many as 10,000 of our suns crammed into that relatively small space. That is about the density of a galaxy that was recently discovered by an international team of astronomers led by a Michigan State University faculty member.

Chemists slide a splitting catalyst over DNA for first time Posted: 24 Sep 2013 09:26 AM PDT Chemists have developed a catalyst that binds to DNA, slides over it, and splits the molecule in particular places. The researchers were able to do this by synthetically modifying a natural catalyst. This finding is a first in the field of chemistry and will help in the selective modification of polymers such as DNA.

Develop after-sex contraceptive pill for routine use, urge researchers: Political opposition biggest hurdle Posted: 24 Sep 2013 08:00 AM PDT A contraceptive pill that could be routinely used after, rather than before, sex and fertilization is probably scientifically feasible and would probably be welcomed by many women, say researchers.

Caffeine consumption slows down brain development, rat study shows Posted: 24 Sep 2013 06:13 AM PDT Humans and other mammals show particularly intensive sleeping patterns during puberty. The brain also matures fastest in this period. But when pubescent rats are administered caffeine, the maturing processes in their brains are delayed, a new study shows.

The dragon awakens: Colossal explosion from supermassive black hole at centre of galaxy revealed Posted: 24 Sep 2013 06:13 AM PDT Two million years ago, a supermassive black hole at the heart of our galaxy erupted in an explosion so immensely powerful that it lit up a cloud 200,000 light years away, astronomers have revealed.

Brain may rely on computer-like mechanism to make sense of novel situations Posted: 23 Sep 2013 02:59 PM PDT Our brains give us the remarkable ability to make sense of situations we've never encountered before -- a familiar person in an unfamiliar place, for example, or a coworker in a different job role -- but the mechanism our brains use to accomplish this has been a longstanding mystery of neuroscience. Now, researchers have demonstrated that our brains could process these new situations by relying on a method similar to the "pointer" system used by computers. "Pointers" are used to tell a computer where to look for information stored elsewhere in the system to replace a variable.

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