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DUCK RESCUE
A last-ditch effort to save the world's rarest duck from extinction – again – has turned a hotel bathtub into a makeshift duckling pond. The pochard duck of Madagascar was thought to be already extinct until a colony of 20 was found in 2006. But when scientists visited their lake in July, they discovered all of the chicks born in 2008 had died and just six of the remaining birds were female, prompting an emergency rescue operation. So far, 17 chicks from two clutches have been moved from the wild to the safety of a hotel in the nearest town, since a washed-out bridge prevents the Wildfowl and Wetlands Trust team from taking them to the capital, Antananarivo. A third clutch of seven eggs is being transferred even before they hatch for fear that the rainy season will make the treacherous road to the lake impassable until spring. The hotel has agreed to let the scientists build some small ponds in its grounds until a permanent, purpose-built rescue centre opens next year. Peter Cranswick from the Trust tells Jon about the challenges, and hazards, faced by the rescue team.

THE BIG THAW
The Arctic tundra has a peaty, boggy surface on top of ancient ice. But as the world warms, this ice is melting and the land is sagging like a deflating soufflé, creating features called thermokarsts. The consequences for civil engineering have been well studied, as the process damages buildings and pipelines. But scientists around the Arctic Circle are now taking a co-ordinated look at the profound affects this great thaw is having on the environment. Once clear streams, for example, are now so clouded with sediment, that fish cannot see the insects they prey on. And whole layers of soil are being detached on islands such as Ellesmere in Nunavut, Canada, allowing them to slip away. Ö÷²¥´óÐã reporter Tracey Logan went to see for herself the dramatic changes to the Arctic landscape.

FLOURISHING PHYTOPLANKTON
At the opposite end of the world, however, global warming is having an unexpectedly positive consequence for life. Since the collapse of the Larsen ice shelf in 2002, phytoplankton, the base of the food chain in the Antarctic, have colonised the newly opened sea, followed by krill and whales. When the algae die, they sink to the sea bed trapping the carbon they've absorbed. Professor Lloyd Peck from the British Antarctic Survey says this new biological activity is soaking up 12 to 13 million tonnes of CO2 a year, the equivalent of a forest the size of Wales. But that's still 1,000 times less than the amount emitted by humans, though it should be included in climate change calculations.

SPEECH GENE
Research in the journal Nature this week describes a gene which seems to control the human ability to speak. FOXP2 works like a dimmer switch, turning the expression of other genes up or down. These genes in turn affect our control of the facial muscles necessary for speech, and may influence the brain circuits involved in language. But, asks Jon, would genetically engineering chimpanzees to carry FOXP2 allow them to talk? Dr Daniel Geshwind from the University of California, Los Angeles, has an answer.

FAST FOOTWORK
What makes a sprinter so swift? When an American football star asked Professor Stephen Piazza from Pennsylvania State University to help his performance, the result was a surprising discovery. The scientist expected to find that the athlete had a long Achilles' tendon. In fact he found the smallest he'd ever seen. But the player also had long toes and a short heel enabling him to produce much more force. Professor Piazza explains the anatomical mechanics.