Trace elements suggest oldest eukaryotes on record

Trace elements found in fossils more than two billion years old hint at the existence of eukaryotes older than any previously on record.

An article in Nature reports the findings of a 21-person team including Stefan Bengtson, a palaeozoologist at the Swedish Museum of Natural History in Stockholm.

The team used mass spectrometry to analyse thumb-sized fossils dated at around two billion years old.

With organisms of that size previously only found as far back as the Cambrian period, 542 million years ago, along with some putative organisms around 1.6 billion years ago, the discovery raises questions about the nature of these multicellular organisms.


Trace elements of sterol compounds hint that they may be eukaryotes, organisms whose complex genetic structures are held in a nucleus surrounded by a membrane.

"The only modern analogue might be microbial colonies, but these tend to be quite small and flimsy," says Mr Bengtson.

"It's quite possible they represent eukaryotes, which tend to make more resilient and larger structures."