In Korea, fossil hunters have discovered long dead spiders preserved in the rock. And to the scientists' delight, the eyes of the arachnids are still brilliant – about 110 million years after the creature's death.
Insects and arachnids – which are much more fragile than shelled sea creatures – are rarely fossilized in rocks. But for reasons still unknown, some of these spiders have fossilized and the unique shape of their eye structures continues to reflect light, even in their petrified form.
The structure of the reflective eye is called a tapetum and is often used by creatures that hunt in the dark.
"Thus, night-hunting predators tend to use this type of different eye," said Paul Selden, director of the Institute of Paleontology's Institute of Biodiversity and Museum of Medicine. 39, natural history of the University of Kansas in a newspaper. "It was the first time a tapetum found a fossil, this tapetum was shaped like a canoe and looks a bit like a Canadian canoe."
Today's wolf spiders use the same eye structures to hunt, Selden said.
However, one mystery remains: how did the spiders fossilize? Their petrified bodies were found in a layer of rock filled with fish and other marine creatures – but the spiders do not stay in the water.
"It must be a very special situation where they have been washed into a water plan," Selden said. "Normally, they would float, but here they sank, which kept them away from the decaying bacteria – maybe it was due to a lack of oxygen."
Selden and his Korean colleagues – who discovered the ancient spiders – must now name the curious fossils. They were discovered only because Korean lands are often searched. Scientists and curious fossils dig to see what ancient innovations are hidden in the earth's crust.
"Then they cut the slopes to form a flat surface.Temporary excavations are done while they cut and build a plant or something else – that's where they found these fossils," Selden said. .