Paleogene fossil shark tooth

Paleogene fossil shark tooth

4 million years ago in the North Sea caused a dramatic loss of biodiversity

The chemical composition of new teeth reflects that of the seas where sharks live

An analysis of fossilized shark teeth reveals that the North Sea was once isolated from the rest of the world's oceans. During a period between 2 and 4 million years, salinity was reduced while the sea became less salty than many lakes, causing a dramatic loss of biodiversity. The results of the investigation conducted by a team of scientists from Germany, Oman and the United Kingdom, have been published in the Journal of the Geological Society.


The objective was to reconstruct the climate of the North Sea during the Paleogene period, between 40 and 60 million years. Just before the start of the Paleogene, 65% of all species (including dinosaurs) disappeared, probably due to the collision of a huge meteorite hit the Earth 65 million years ago. The brand Paleogene therefore an important period of diversification of mammals.

The climate at that time was relatively warm, but even though scientists have discovered many facts about the climate on Earth during this period, less is known about what was happening in the marginal seas like the North Sea.

Link: http://www.vistaalmar.es/content/view/762/28/