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18 | NewScientist | 14 August 2010 AS RAMADAN begins this week, pregnant women deciding whether to take part in the customary fast may wish to consider the effect on their babies. So says Nick Ashton at the University of Southampton, UK, and colleagues at King Saud University in Riyadh, Saudi Arabia. They analysed records of 7000 babies born in a Saudi hospital over a four-year period, and worked out during which trimester, if any, of their mother’s pregnancy Ramadan fell. Surveys indicate that over 90 per cent of pregnant Muslim women fast. While babies’ birth weights were similar in fasting and non-fasting Saudi women, the placentas of women who had fasted during the second or third trimester were 3 per cent lighter than average when the child was a boy and 1.5 per cent Klepto keas crack locks, no problem Kea parrots are renowned thieves in their native New Zealand, and with good reason – even a complicated sequence of locks can’t foil them. Hiromitsu Miyata of Kyoto University in Japan first presented keas with boxes of food secured with up to three bolts. The parrots managed to open all of them, so he made the tasks harder. The most challenging set-up involved two bolts blocking each other such that one needed to be slid open before the second would release. Miyata found that the keas cracked this problem faster if they were allowed to study the set-up for a while before attempting to break it (Animal Cognition, DOI: 10.1007/s10071- 010-0342-9). This suggests they are able to plan their moves, he says. Until now, the birds were thought to tackle problems in a haphazard fashion. Ignore the dynamite, but never forget to fear humans ELEPHANTS are not fazed by dynamite explosions, but change their behaviour significantly to avoid humans. That is the finding of a major study of how forest elephants deal with oil exploration in central Africa. Peter Wrege and colleagues at Cornell University in Ithaca, New York, used listening devices similar to those designed to eavesdrop on whales to monitor the sounds and seismic activity of oil prospecting in the Loango National Park in Gabon. After collecting 27,000 hours of recordings, the team analysed how dynamite blasts and other human activity, such as driving and setting MICHAEL NICHOLS/NATIONAL GEOGRAPHIC IN BRIEF Baby affected if you fast while pregnant lighter for girls (Placenta, DOI: 10.1016/j.placenta.2010.04.010). Children born with placentas that are smaller than average are known to have an increased risk of cardiovascular disease later in life, though it is too early to advise pregnant women whether to fast, Ashton says. “Birth weight isn’t affected, which is good, but we need to see whether a small placenta affects the risk of cardiovascular disease in these children in the long term.” up equipment, affected the number of elephant calls. Elephants are active both during the day and at night. Those in the study did not flee the areas where oil prospecting was taking place, but those closest to the activity became increasingly nocturnal. Acoustic data suggested these changes were linked to workers moving through the forest and setting up equipment, not the detonation of dynamite (Conservation Biology, DOI: 10.1111/j.1523-1739.2010.01559.x). “Dynamite might sound like intense thunder,” says Wrege. Blasts could therefore seem harmless, whereas elephants in the region have long been hunted by humans. The behavioural changes could have caused extra stress and competition for food, since the elephants had less time to go about their daily activities, he says. VERTICAL pupils aren’t just for night vision, they also help snakes stalk prey without being seen. Richard Shine at the University of Sydney, Australia, compared pupil shape with hunting behaviour in 127 species of snake. This revealed that snakes that ambush prey at night tend to have vertical pupils; round pupils are typical of diurnal snakes that stalk and pursue their prey (Journal of Evolutionary Biology, DOI: 10.1111/j.1420-9101.2010.02046.x). Slit pupils offer a deeper field of focus but still let enough light into the eye for night vision. This may help snakes waiting in ambush as they wouldn’t have to move forward to see prey in focus – and risk being seen. This could be true in other animals, too. Snakes’ slit pupils help ambush prey
