Humans likely first took to the seas about 50,000 years ago. But there's mounting evidence that our Neanderthal cousins were routinely sailing throughout the Mediterranean twice as long ago. Alternatively, they were just really good at long distance swimming.
These days, the dusky grouper is a major predator in the Mediterranean Sea, generally growing to about two feet long. But that wasn't always the case...and ancient mosaics provide a rare chance to see what this beast used to be.
The Olympic Games first began in the ancient Greek city-state of Olympia. For all its fame, the city suffered a mysterious fate, destroyed by an unknown natural disaster. Now it looks like tsunamis were the culprit...despite being 30 kilometers inland.