ScholarScribe

Sea turtle scent

The primary food for many sea turtles is jellyfish and, let's face it, this is not an interaction that one would expect to be particularly complicated. Sea turtles are immune to the sting of their prey and just swim up the drifting animals for a bite. Yet on the grander scale, this is actually quite a complicated predator/prey interaction since sea turtles travel thousands of miles across the oceans and jellyfish only live in very specific areas of high oceanic productivity known as upwelling zones. This led a team to wonder how exactly turtles figure out where to find their prey. The obvious answer seemed their geo-magnetic sense. Turtles have something akin to GPS and use this sense to guide them during their lengthy journeys. However, their geo-magnetic sense is nowhere near accurate enough to guide them to something as small as an isolated upwelling zone.

Curious about how they were homing in, a team of researchers explored the world of turtle scent. Sea turtles, being reptiles, must surface every once in a while to breathe. The team knew that the compound dimethyl sulfide acculates in the air above highly productive oceanic areas like upwelling zones and speculated that turtles might be using the smell of this foul chemical to track fertile zones down. Read more in my article in The Economist.
 

Sweeping mine sweepers for mines

For years, the U.S. navy has employed human divers, equipped with sonar cameras, to search for underwater mines attached to minesweeper hulls. The navy has also trained dolphins and sea lions to help in these searches. Yet both tactics are less than ideal. While animals can cover a large area in a short amount of time, they are costly to train and care for and don’t always perform as expected (squirrel!!). Humans are easier to train and less prone to being distracted by fish swimming by, but have families that greave for them when they get blown up. Thus the navy is now looking to robots as a third option.

In the last few years, researchers around the world have been engineering resilient robots for minesweeping and other risky underwater missions. The ultimate goal is to design completely autonomous robots that can navigate and map cloudy underwater environments— without any prior knowledge of those environments and detect mines as small as an i-Pod. However, designing algorithms that can help these robots navigate the complex topography of a ship's hull has not been easy. The trouble is that the robots cannot just view hulls from a safe distance, they must get the big picture but also get close and fly through the propellers and rudders. To make this work, a team developed a new program for mine seeking robots that has them sweep in a two-step process. Read more in my article in The Economist.
 

Meet the glacier mouse

Life has been discovered in a truly bizarre place, inside glacier mice. These "mice" are not rodent or even mammals, but balls of moss that slowly grow on pebbles resting on glaciers. As the glacier moves, melts and changes, the mice roll around and then blow across glaciers much like tumbleweed in deserts. This rolling makes them nearly perfectly round spheres of moss that lack a bottom.

Researchers know that it takes decades for these mice to grow but that is about it. Now a new study is revealing that they are effectively tiny mobile homes. The mice are providing shelter to animals that would otherwise not survive for long in the fierce cold of the arctic environment. Read more in my New York Times article.
 

The potential to tame hurricanes

A team is arguing that there is the potential to cool ocean surface waters in regions where hurricanes frequently form and thus reduce the strength of hurricanes that form in the area. Their idea circles around the concept of cloud seeding, a tactic used by the Chinese during the 2008 Olympics to make clouds form in areas other than Beijing. They theorise that by creating higher cloud droplet density, clouds in the hurricane generating area would develop higher levels of reflectivity to incoming sunlight and keep surface water cooler.

They have thrown all of their numbers into a climate ocean/atmosphere coupled model and demonstrate that considerable seeding of dense clouds significantly reduces sea surface temperatures and would likely reduce the size and strength of hurricanes born in such places. Of course, what works on a computer model is not necessarily what works in real life, but considering the billions in damage caused every year by these storms, testing the idea out makes economic sense. Read on in my article in The Economist.