Petrified wood from Madagascar, 10 x 8 x 21cm. Petrified wood is a special type of fossilized remains of terrestrial vegetation. It is the result of a tree or tree-like plants having completely transitioned to stone by the process of permineralization. All the organic materials have been replaced with minerals (mostly a silicate, such as quartz), while retaining the original structure of the stem tissue.
'Missing link' found for spectacular ancient sea reptiles
Scientists said on Wednesday they have unearthed in China the fossil of a small ichthyosaur with large, flexible flippers that let it move around on land like a seal while spending most of its time in the water 248 million years ago. They called it the long-sought missing link revealing the early evolution of ichthyosaurs, one of the dominant marine reptile groups during the age of dinosaurs. Nov. 5, 2014