Praying mantises use their stereoscopic vision system unlike any other known animal. Vertebrate animals use stereoscopic vision to perceive depth — but the praying mantis is the only known insect to possess it. And the insects were able to prevail in depth perception problems that confounded humans. The findings, in the journal Current Biology, said the insects have developed a sophisticated ability with a tiny brain (with only a million or so neurons compared with humans’ 100 billion.) The scientists think it’s because the insects are basically looking for only things that move — a discovery that could help design future robots that would require less computing power.

Rare cave site in Mexico under threat

Pollution is threatening the Sac Actun cave system in the Yucatán Peninsula, a vast underground network that experts in Mexico say could be the most important underwater archaeological site. Subaquatic archaeologist Guillermo de Anda said some of the oldest human remains on the continent have been found there, dating back more than 12,000 years. But he said pollution and development may threaten the caves’ crystalline water. The main highway in the Caribbean coast state of Quintana Roo runs over some parts of the cave network. And the cave with the stone-encased skull has high acidity levels, suggesting acidic runoff from an open-air dump could damage remains.

Volcanic blast reshaped Mountain

The eruption of Indonesia’s Mount Sinabung that shot ash 3 miles high also blew away much of the mountain’s summit. Before and after images from Indonesia’s Center for Volcanology and Geological Hazard Mitigation show an enormous chunk missing from the peak, which it called “completely annihilated.” Volcanologist Devy Kamil Syahbana said the chunk, known as the “lava dome,” had a volume of at least 56.5 million cubic feet. Mount Sinabung is among more than 120 active volcanoes in Indonesia, which is prone to seismic upheaval because of its location on the Pacific “Ring of Fire.”

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