If you thought that once upon a time, happy dinosaurs were killed off by a giant, blazing rock with "death from above" written all over it, you may only be half right. According to the latest research, the impact probably killed the larger land creatures, but the smaller species could have succumbed to a more watery fate. Curious? read the full article for the skinny on it.

Underwater cave explorers Robbie Schmittner of Germany and Steve Bogaerts of the United Kingdom are claiming that they have found what is certainly the world's largest underwater cave system in the heart of the Yucatan peninsula in Mexico.

They discovered that the Nohoch Nah Chich system in Maya is actually connected to the Sac Actas system, officially sealing the notion that the two cave systems were actually one big cave. The discovery puts the previously-recognized largest underwater cave Ox Bel Ha (also found in Yucatan) to second place.

The pair says that it took over 500 dives to completely document their explorations and come to the conclusion that the entire Yucatan underground water system is actually connected in one way or another.

Bogaerts explains that by diving into sinkholes, which are essentially lakes formed from underwater caves whose ceilings have collapsed, they were able to see how passageways deep in these bodies of water led from one to another. More important than the discovery itself, he says, are the environmental and economic implications of the discovery.

It's not a secret that Yucatan is among the fastest rising resort locales in the world. Given the fact that a lot of these resorts are dependent on the water supply, there is a high risk of pollution from human activities. "There are so many cave systems that if there's a point of pollution in any one particular area it can spread very extensively throughout the entire system." says Bogaerts.

The area is also a cultural tourist attraction, as Maya Indians once lived off the land by depending on the water from the lakes and caves.