Biology researcher Dr. Ryan Gregory explained to Scientific American why some salamanders have massive genomes (a complete DNA sequence). 

In the article, Gregory said Neuse River Waterdog’s transposons, a type of DNA that jumps from one location to another in a genome, are maladaptive. He said they have evolved to place themselves into the salamanders’ DNA without affecting their genes, hence becoming junk DNA and creating enormous genomes.  

Chair of the Department of Integrative Biology, Gregory studies large-scale genome evolution and integrative genomics and evolutionary biology.