Geese hug Himalayas on high-altitude trips
It has been called the most extreme migration on Earth: Twice a year, bar-headed geese fly over the Himalayas between India and Central Asia. Now scientists say they have discovered how the birds manage the high-altitude journey.
Like riders on a roller coaster, the geese hug the terrain as they fly, rising and falling with the peaks and valleys. By taking advantage of lower and denser air, the birds conserve more energy than they would by flying steadily at very high altitudes.
“We know that quite a few birds on migration fly quite high in order to catch tail winds,” said Charles Bishop, a zoologist at Bangor University and lead author of the study. “But when we looked, we saw the geese were working really hard to get up, then coming back down again.”
To conduct the study, published in the journal Science, Bishop and his colleagues implanted in seven geese devices that monitor heart rate, abdominal temperature, air pressure and the frequency of wing beats. Knowing that wing-beat frequency increases in the thin air of high altitudes, the researchers were able to determine where the birds were and how much energy they were expending.
“Flying at high altitude is much harder than we thought,” Bishop said. “If the geese stay high and don’t have a tail wind, then it’s very hard work to stay there.”
Facebook knows you better than anyone
Think your friends know you well? Researchers have developed a computer model that can judge someone’s personality more accurately than their friends and family – using nothing but the subject’s Facebook activity.
Researchers at the University of Cambridge and Stanford University tested their algorithm on more than 17,000 Facebook users, who completed a personality survey and provided the researchers with access to their “likes.” Many of their friends, colleagues and family members also completed a survey describing the users.
The survey rated each subject on the five OCEAN personality traits: openness, conscientiousness, extraversion, agreeableness and neuroticism. Then the researchers compared those results to the subjects’ Facebook activity to establish links between “likes” and specific personality traits.
Given enough data, the algorithm was better able to predict a person’s personality traits than any of the human participants. The study, published in Proceedings of the National Academy of Sciences, suggests that computers could replace humans in practical settings that require personality analysis, said the lead author, Youyou Wu, a graduate student in psychology at Cambridge.
“People are already doing this manually with questionnaires,” Wu said, “but in the future, the process could be automated so it could be applied efficiently and reliably.”
– New York Times