The first study to systematically measure the number of neurons in the brains of birds has found that they have significantly more in their small brains than mammalian and primate brains of the same mass.
The macaw has more neurons in its forebrain - the portion of the brain associated with intelligent behaviour - than the macaque.
The study, published in the Proceedings of the National Academy of Sciences, measured neurons in the brains of more than two dozen bird species..
World's oldest beer?
The Queen Victoria Museum and Art Gallery in Launceston, Tasmania, has identified what is believed to be the world's oldest beer, surviving as contents of a bottle salvaged from the protected historic shipwreck Sydney Cove - circa 1797 - at Tasmania's Preservation Island.
The museum's staff, in collaboration with international researchers, managed to isolate and extract live yeast from the 220-year-old beer, allowing a taste not experienced for more than two centuries.
Science of happiness
Scientists have used a new equation to show how our happiness depends not only on what happens to us but how this compares to other people.
Using a happiness-measuring equation developed in 2014, researchers found inequality reduced happiness on average - and this was true whether people were doing better or worse than another person they had just met in an experiment.
Participants in the study just published in Nature Communications gambled to try to win money and saw whether another person won or lost the same bets.
On average, when someone won , they were happier when the other person also won.
When people lost they were happier to see the other person lose.
Are our kids shallow?
In a study published in Frontiers in Psychology, researchers found that as children, how we perceive someone's trustworthiness is linked to how attractive we find them.
Our ability to make this trustworthiness judgment develops as we grow, becoming more consistent as we approach adulthood, and girls are better at it than boys, according to the study.
Many psychology studies have proven the existence of the phenomenon whereby more attractive people are also considered to be smarter, more sociable and more successful.
Smelling out crooks
Police lineups normally rely on sight, but nose-witnesses can be just as reliable, new research has found.
"Police often use human eyewitnesses and even ear-witnesses in lineups, but, to date, there have not been any human nose-witnesses," said Professor Mats Olsson, an experimental psychologist at the Karolinska Institutet in Sweden. "We wanted to see if humans can identify criminals by their body odour."
Dogs have been used to identify criminals through body odour identification in court, but it is thought the human sense of smell is inferior to that of other mammals.
However, research shows that humans have the ability to distinguish individuals by their unique body odour.
Olsson and his colleagues were able to show that the ability to distinguish the criminal's body odour in a lineup was possible - but the ability was significantly impaired if the lineup was conducted after one week of having smelt it.