A trace fossil of an iguana burrow was discovered on San Salvador Island in the Bahamas. Estimated to be 115,000 years old, it is the first known fossil of its kind.
And here's what to do once a future sinkhole has been identified.
Following NASA's latest discovery of organic matter on the red planet, new findings in a salt lake in California could point to where to look for alien life.
Cement has a huge greenhouse footprint, largely because the chemical process by which it is made releases carbon dioxide. But there are several different ways for cement to green up its act.