Thursday June 6, 2024
Earth.com —
The British Isles, known for their picturesque landscapes and winding rivers, harbor a hidden marvel within their waterways — genetically distinct trout populations thriving in metal-polluted river environments.
These seemingly ordinary fish have evolved into resilient survivors, yet their isolation and lack of genetic diversity raise concerns about their future.
A new study has revealed the genetic secrets of these remarkable trout. By analyzing the DNA of brown trout from 71 sites across Britain and Ireland, researchers discovered that those living in metal-polluted rivers are genetically isolated from their counterparts in cleaner waters.
“We found massively reduced genetic diversity in some of these trout populations inhabiting metal-impacted waters,” explained Professor Jamie Stevens from the University of Exeter.
“These fish carry a high burden of metals, with toxic binding of dissolved metals to their gills causing suffocation, but trout that can tolerate this have emerged in polluted rivers.”