Prehistoric Frogs in Amber Surface After 99 Million Years
Frogs trapped in amber for 99 million years are giving a glimpse of a lost world.
The tiny creatures have been preserved in sticky tree resin since the end of the Age of the Dinosaurs.
The four fossils give a window into a world when frogs and toads were evolving in the rainforests.
Amber from Myanmar, containing skin, scales, fur, feathers or even whole creatures, is regarded as a treasure trove by palaeontologists.
Dr Lida Xing of China University of Geosciences in Beijing said it was a "miracle" find.
"In China, frogs, lizards and scorpions are called three treasures of amber," he told BBC News.
"These amber fossils provide direct evidence that frogs inhabited wet tropical forests before the mass extinction event at the end of the Cretaceous."
The fossil record of the earliest amphibians is sparse, which makes the discovery particularly valuable for science.
Dr David Blackburn of the University of Florida, who worked on the fossils alongside Dr Xing, said being small and living in a tropical forest makes the likelihood of ending up in the fossil record "pretty low".
"Frogs have been around on earth for approximately 200 million years," he said.
"How long have they been associated with these wet forests? Is it a recent phenomenon or an ancient one? These amber frog fossils indicate that this association extends back to at least 100 million years ago."