Aside from the competition for food and habitat, one of the larger worries of biologists now has to do with hybridization because of the ability of cutthroat trouts and rainbow trouts to interbreed (Rubidge 2011). Hybridization may not appear to be a big deal but the change of gene flow actually has much to do with how successful a species can be.
The best way to first look at the matter of hybridization is to examine how allele frequencies have changed due to interbreeding. There was a study done where scientists analyzed the allele frequencies of two groups of cutthroat trout populations living in two different creek systems (Metcalf 2008). Both of these have a degree of exposure to nonnative rainbow trout through stocking. However, the rainbow trout population was chemically controlled at Cony Creek so that a comparison could be done between the two creeks. It's also important to note that both creeks had a waterfall diving the upper and lower stream with the rainbow trout present in the lower part of the stream so that they would not be able to migrate upstream, only the native cutthroat trout could migrate downstream through the waterfall. Below shows the data that was collected about allele frequencies in each population of fish.
It is evident that with the presence of the uncontrolled population nonnative rainbow fish the allele frequency in cutthroat trouts drastically decreased.
The best way to first look at the matter of hybridization is to examine how allele frequencies have changed due to interbreeding. There was a study done where scientists analyzed the allele frequencies of two groups of cutthroat trout populations living in two different creek systems (Metcalf 2008). Both of these have a degree of exposure to nonnative rainbow trout through stocking. However, the rainbow trout population was chemically controlled at Cony Creek so that a comparison could be done between the two creeks. It's also important to note that both creeks had a waterfall diving the upper and lower stream with the rainbow trout present in the lower part of the stream so that they would not be able to migrate upstream, only the native cutthroat trout could migrate downstream through the waterfall. Below shows the data that was collected about allele frequencies in each population of fish.
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| Figure 3
The frequency of cutthroat trout mtDNA versus nuclear DNA in Cony Creek (top) and Graneros Creek (bottom). The area of the circle is proportional to the sample size at that point. The black line in each graph represents the expected trend under random mating (slope = 1). Points below the line signify a lower than expected proportion of cutthroat mtDNA.
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It is evident that with the presence of the uncontrolled population nonnative rainbow fish the allele frequency in cutthroat trouts drastically decreased.
This information is great but stylistically for the public you may want to try and edit your text so there's not so much of it. Maybe also explain how the simulation works and highlight your conclusion.
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