Epigenetics enabling fish survival

A number of fish species are adapting to survive warmer oceans without genetic changes, according to researchers from the University of East Anglia.  

Researchers discovered skate in the warmer southern Gulf of St Lawrence had a body size 45% smaller than their counterparts in the Scotian shelf in Canada with a significantly shorter life span, albeit with a faster maturation time. This provides hope that species threatened with climate change, such as sharks and rays, could adapt quicker without genetic changes caused through evolution.

Dr Jack Lighten, first author from the University of East Anglia, said: “The Winter Skate has been able to adapt to a dramatically different environment over a short evolutionary time, with apparently little genetic change. These adaptive changes in life history, physiology and phenotype have occurred through epigenetic regulation, causing changes in gene expression, enabling the species to respond rapidly to environmental challenges.”

The skates’ adaptations are due to epigenetic changes – where gene expressions are modified. This is particularly important for species such as skate which have both a low reproductive output and long maturation times, as they are more likely to evolve slowly.

Researchers compared an endangered, smaller population Winter Skate (Leucoraja ocellata) in waters around 7000 years old and 10°C warmer at the southern Gulf of St Lawrence in Canada with a larger population on the Scotian Shelf in Canada. They have existed for more than 150 million years, surviving two mass extinctions

The scientists worked in conjunction with researchers from Dalhousie University in Canada and their research was published in Royal Society Open Science.