This week on radio, Tim Thwaites is talking about how eggs woo sperm; plants that jump the fence; robots that hide; hanging around Mercury; and moreHow human eggs woo sperm—When a human egg is ready to be fertilised it releases a “come hither” hormone to attract nearby sperm. American and German scientists now know how it works. And figuring out how to turn the signal off could lead to effective, non-hormonal, unisex contraceptives with few side effects.—Nature
A Nature story on this topic can be found at http://www.nature.com/news/2011/110316/full/news.2011.163.html
Low testosterone linked with financial risk taking—Conjure up an image of a financial risk-taker and you will likely end up with Gordon Gecko-like figure, high on testosterone as he closes the deal. But a US research group has found that people with very low levels of the male hormone also take bigger risks than average.—Psychological Science
A New Scientist story on this topic can be found at http://www.newscientist.com/article/mg20928044.300-low-testosterone-linked-with-financial-risktaking.html
Navy sonar may mimic killer whale sounds Sonar can drive beaked whales long distances from their favourite deep-water habitats, sometimes into dangerously shallow water, the first study conducted during actual US Navy exercises has shown. The work also suggests that the levels the navy considers “safe” may well be too high.—PLoS ONE
A Science story on this topic can be found at http://news.sciencemag.org/sciencenow/2011/03/navy-sonar-may-mimic-killer-whal.html?ref=hp
Botanic gardens blamed for spreading plant invaders—More than half the world’s invasive plant species spread into new habitats from botanic gardens, an analysis by New Zealand scientists has concluded. Although most cases of this happened before the 1950s, reports of recent releases suggest biosecurity could be tightened.—Trends in Ecology
A Nature story on this topic can be found at http://www.nature.com/news/2011/110318/full/news.2011.169.html
MESSENGER arrives safely at Mercury—After 6½ years and nearly 8 billion kilometres, the US MESSENGER spacecraft has finally made it to Mercury. It should be sending back its first images later this month.—Science
A Science story on this topic can be found at http://news.sciencemag.org/sciencenow/2011/03/scienceshot-messenger-arrives.html?ref=hp
Surveillance robots know when to hide—US defence firm Lockheed Martin has demonstrated a prototype surveillance robot that can hide if it is likely to be seen by humans. The company has already developed a stealthy aerial drone that can carry eavesdropping microphones or cameras.—New Scientist
A New Scientist story on this topic can be found at http://www.newscientist.com/article/mg20928044.700-surveillance-robots-know-when-to-hide.html