Scottish slime may have been the key to evolution


SCOTLAND has been home to many inventions and world firsts but now scientists believe Scottish slime may have provided the key to evolution.

From John Logie Baird’s invention of the television to James Watt’s steam engine, Scots have been behind some of the planet’s most important inventions.

And now it has been revealed that the country may have played a crucial role in the evolution of terrestrial life.

Fossil finds in rocks that are over 400 million years old near Rhynie, Aberdeenshire, are helping scientists better understand how life moved from its early stages in water to land before eventually turning into plants and animals.

The rocks at Rhynie date from a time when Scotland was part of a much larger land mass south of the equator.

Algae, similar to pond slime, had been on the land for tens of millions of years but evolution remained slow.

However, Rhynie was different because it contained hot springs nearby which plants and animals competed to grow, thus speeding up evolution.

Liam Dolan, professor of botany at Oxford, recently published research on how the Rhynie fossils helped evolution.

He said: “These discoveries have huge scientific and cultural significance.

“The Rhynie rocks are a treasure trove revealing how plants evolved to colonise land and so provide food and resources needed for animals to follow.

“Scotland has played a huge part in our understanding of Earth’s history.”

Dianne Edwards, professor of palaeobotany at Cardiff University is co-organising a Royal Society conference to discuss the significance of the Rhynie fossils and said: “We found 17 species of fungi, seven species of higher plants and small animals like centipedes and early insects.

“We also found the earliest sex organs of any known land animal in a harvestman spider.”
Paul Kenrick from London’s Natural History Museum believes that increasing competition in Rhynie forced species to evolve.

He said: “Plants then were mostly small. The ground would have been covered in knee-high vegetation and the top predators were spiders and other small animals.

“But they were competing for light and other resources. By 385 million years ago we see the first forest ecosystems evolving.”

Scotland was more attractive for bigger animals moving onto land because the bigger plants meant more food resources.

Some scientists believe that Scotland’s claim to be the birthplace of terrestrial life can be traced back to one billion years ago when most life was just single cells dependent on water.