Yuka Mammoth (Photo : Wikimedia Commons) Yuka is the best-preserved carcass of a woolly mammoth (Mammuthus primigenius). Local Siberian tusk hunters found it in 2010. They handed it over to local scientists in 2012, who conducted an initial examination of the carcass. It can be seen as a display in Moscow. The mammoth was discovered on the Oyogos Yar coast, about 30 kilometers west of the Kondratievo River's mouth in Siberia's Laptev Sea district. Yuka is a juvenile female natural mummy that was discovered near the village of Yukagir and named after the people who found it. Cyanobacteria (Photo : Wikimedia Commons) Cyanobacteria have a long history of fossilization. A Cyanobacteria from Archaean rocks in western Australia are the earliest known fossils, dating back 3.5 billion years. This may come as a surprise, given that the oldest rocks are just 3.8 billion years old.