'Grape' is key to fossil puzzle

[Eugene]

Source: BBC News

Page last updated at 09:29 GMT,
Friday, 21 November 2008

'Grape' is key to fossil puzzle

A single-celled ball about the size of a grape may
provide an explanation for one of the mysteries of
fossil history.

Writing in Current Biology, researchers say the
creature leaves tracks on the seabed which mirror
fossilised tracks left up to 1.8 billion years ago.

Many palaeontologists believe only multi-celled
organisms could have made these tracks.

-snip-

This dating presented a problem for palaeontologists;
they assumed multi-cellular organisms with bilateral
symmetry, where two halves of their bodies are
approximate mirror images of each other, had to be
responsible for such tracks, but there is no fossil
evidence for the existence of such creatures until
several million years later.

-snip-

Dr Matz believes protists provide an explanation of
how the tracks could have been made without the
need for organisms with bilateral symmetry.

-snip-

Read more: http://news.bbc.co.uk/2/hi/science/nature/7739703.stm