Heritable Variation Discovered in Trout Behavior

Source: University of Eastern Finland 
Date of Publication: March 13, 2014
Link: http://www.sciencedaily.com/releases/2014/03/140313092219.htm

Summary: 
Recently, researchers have noticed that endangered salmonids' catches have decreased. Previous research has shown that certain behavioral traits explain individual differences in how fish survive in the wild. A new Finnish study conducted on brown trout now shows that there are predictable individual differences in behavioral traits, like tendency to explore new surroundings, activity, and stress tolerance. Certain individual differences were observed to contain heritable components. A study was carried out in the Finnish Game and Fisheries Institute's Kainuu Fisheries Research Station in Paltamo: they discovered that the behavioral traits examined were individually repeatable. Fish showed personality. Furthermore, certain behaviors related to stress tolerance, such as freezing, showed statistical heritability at a level of 14%. This means that it is not random that mortality related to stress tolerance both in fish farms and in the wild can modify the heritable traits of fish populations and lead to changes that are difficult to reverse. This is bad for humans, because these changes might weaken the ability of fish to avoid predators and decrease the fisheries' catches unless mitigated by acknowledging the potential selection acting on fish personality.


Relevance: This article is relevant to what we are doing in class for 2 main reasons. Firstly, in chapter 9.5, we talked about how meiosis functions in sexual reproduction, and in a sexually reproducing species inherits a unique combination of genes from its two parents. So for example: people resemble the other members of their family more than they resemble a stranger, but they do not look exactly like their parents or siblings. In this article, mother fish can pass some of it's hereditary material onto it's off springs (14%), and that fish don't look or act, exactly like each other. Secondly, in chapter 14.1, after Darwin went on the HMS Beagle, and collected evidence from geology, he published his theory- the first of two main points Darwin presented was "Descent with Modification": descendants from earlier organisms spread into various habitats over millions of years. And in these habitats, they accumulate different modification or adaptations to diverse the ways of life. It is the same thing with the fish in my article, they have live in the same habitat, but they certainly do have different  traits that they have adapted, they would make the fish population have more diversity.