Scientists at Glasgow University say that Scotland’s oldest freshwater fish could help answer one of the most fundamental questions about life on earth. The rapidly changing and highly diverse Arctic Charr could reveal what drives evolution.

What is the Arctic Charr?                                         

The fish is a relative of the Atlantic salmon and brown trout, and it came to Scotland at the end of the last ice age, around 12,000 and 14,000 years ago. You could even say that the Arctic Charr is the aboriginal freshwater fish of Scotland, with some fish accessing marine waters if available. They have the most northerly distribution of any freshwater fish.

How Will They Help Reveal What Drives Evolution?

They inhabit more than 250 lochs in Scotland, and surveys have discovered significant genetic, physical and behavioural differences between the different populations.

The director of the university’s Scottish Centre for Ecology and the Natural Environment, Professor Colin Adams, and his team are trying to discover a reason for this difference.

“Evolution is the most fundamental driving force in the natural world,” he said. “It is the process that gives rise to new species and gives us the wonderful biodiversity in the natural world that we cherish.

“Despite that we have known about the basic process for over 150 years we still do not fully understand how evolution works in some circumstances. One of the things is how it can, at times, operate very quickly.”

Some experts believe that the different populations so vary in a range of characteristics that they should be reclassified into distinct species. These characteristics, such as different colouring, head shapes and body shapes, as well as less obvious ones, have developed in adaptation to conditions in particular lochs.