Research on a treasure trove of amber has yielded evidence that France once was covered by a dense tropical rainforest with trees similar to those found in the modern-day Amazon. The report is on 55-million-year-old pieces of amber from the Oise River area in northern France.

In the new study, Akino Jossang and colleagues used laboratory instruments to analyze the fossilized tree sap in an effort to link specific samples of amber to specific kinds of trees. The amber remained intact over the ages, while the trees from which it oozed disappeared. Efforts to make such connections have been difficult because amber from different sites tended to have very similar chemical compositions. The report describes discovery of a new organic compound in amber called “quesnoin,” whose precursor exists only in sap produced by a tree currently growing only in Brazil’s Amazon rainforest.

Researchers say that amber probably seeped out of a similar tree growing in a tropical forest that covered France millions of years ago before Earth’s continents drifted into their current positions. “The region corresponding to modern France could have been found in a geographically critical marshy zone belonging to Africa and a tropical zone 55 million years ago extending through North Africa to the Amazon,” the report states. — AD

Article: Quesnoin, a Novel Pentacyclic ent-Diterpene from 55 Million Year Old Oise Amber, The Journal of Organic Chemistry