Salmon are shrinking, and it shows in their genes
(PHYSorg.com Biology)

Male salmon are maturing earlier and becoming smaller, and it shows in their genes. This was the discovery of a study that examined scale samples from salmon in the River Teno in Northern Finland over a 40-year period, and looked at the population genetic profile of a gene that determines salmon`s age of maturity and size. The results show that the `big salmon gene version` has become rarer in the population over time, and has been replaced by the `small salmon gene version`.