Over at BioLogos, Dennis Venema provides the conventional view of transposons through a non-teleological prism. Like many others, he thinks of transposons as parasites:
They are the perfect parasites: using their host to provide resources so they can replicate themselves, and with a “lifestyle” so simple that replication is essentially its only feature.
And
Despite their parasitic nature, sometimes the host species can exploit transposons as a source of genetic novelty.
Yet it is not really accurate to describe transposons as parasites.
designmatrix.wordpress.com 