A weird marine creature that lived 500 million years ago at a time of explosive growth in Earth's biodiversity could be a forerunner of worms and molluscs, a study published on Thursday said.

Palaeontologists in China and Europe have taken a second look at fossils of a species called Cotyledion tylodes -- a small animal that, when it was identified in 1999, was at first thought to be a cnidarian, or part of a group of jellyfish-like species.

Temperatures in Sydney hit their highest level on record on Friday, with the mercury in Australia's biggest city reaching 45.8 degrees Celsius (114.4 Fahrenheit) in the mid-afternoon.

Sydney's previous hottest recorded temperature was 45.3 degrees set in 1939.

A 14-year study of a nearly 1,000 elephants in Kenya shows an alarming death rate among older males — those with large, valuable tusks — and an acceleration in poaching deaths, the group Save The Elephants said Thursday.

The study said that in 2000 the region of Samburu had 38 known elephant males over 30 years of age. But 2011 only five of those original 38 were still alive. Almost half of the known females over 30 years also died during this period, at least half from illegal killings, the study found.

Land unfit for growing food could make a big contribution to the United States' biofuel needs with wild-growing, non-grain crops, a study said Wednesday.

So-called marginal land in 10 states in the American Midwest could produce as much as 5.5 billion gallons of ethanol per year, a team of researchers wrote in the journal Nature.

A lobster thrown live into boiling water may suffer for many seconds, said a scientist who argued Thursday that crustaceans can likely feel pain.

A set of experiments on crabs revealed that the animals are willing to give up a valuable dark hiding place in order to avoid an electric shock, an indicator of pain, said a study in the Journal of Experimental Biology.

The U.S. and European space agencies announced a new partnership Wednesday pairing a European cargo module with NASA's Orion space capsule, which aims to take astronauts into deep space.

The agreement covers Orion's first planned mission, set for 2017, which will take the spacecraft on an unmanned fly-by around the moon.

The complex social structure of the red fire ant, a fast-spreading invasive insect with a painful bite, is made possible by a DNA fusion known as a supergene, biologists said Wednesday.

It is the first study to link supergenes to animal behavior, the scientists reported in the journal Nature, and predicted a similar effect would be found in other species.

The European Commission hinted on Wednesday that it could ban several insecticides, some made by German chemicals giant Bayer, after scientists found disturbing evidence of harm to bees.

The EU's food saftey agency had reported "disturbing conclusions on three types of insecticides," a spokesman for EU Health Commissioner Tonio Borg said.

The Mars rover Curiosity will soon begin to drill into the Red Planet for the first time, mission officials said Tuesday ahead of the highly anticipated endeavor.

Scientists behind the $2.5 billion mission also explained the nature of the small "Martian flower," which had caused a lot of buzz online because it was strikingly different from the surrounding rock.

South Korea will make another bid at the end of this month to put a satellite in orbit and gain entry to an elite global space club that includes Asian powers China, India and Japan.

The Ministry of Education, Science and Technology announced Wednesday a January 30-February 8 window for launching the 140-tonne Korea Space Launch Vehicle-1 (KSLV-1) from the Naro Space Center on the south coast.