title: Horizontal transfer of short and degraded DNA has evolutionary implications for microbes and eukaryotic sexual reproduction.
abstract: Horizontal gene transfer in the form of long DNA fragments has changed our view of bacterial evolution. Recently, we discovered that such processes may also occur with the massive amounts of short and damaged DNA in the environment, and even with truly ancient DNA. Although it presently remains unclear how often it takes place in nature, horizontal gene transfer of short and damaged DNA opens up the possibility for genetic exchange across distinct species in both time and space. In this essay, we speculate on the potential evolutionary consequences of this phenomenon. We argue that it may challenge basic assumptions in evolutionary theory; that it may have distant origins in life's history; and that horizontal gene transfer should be viewed as an evolutionary strategy not only preceding but causally underpinning the evolution of sexual reproduction.
authors.affiliation: Centre for GeoGenetics, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Søren
authors.initials: S
authors.lastname: Overballe-Petersen
authors.forename: Eske
authors.initials: E
authors.lastname: Willerslev
mesh_terms: D000818:Animals; D001419:Bacteria / Q000235:genetics*; D005075:Biological Evolution; D004247:DNA / Q000235:genetics*; D004249:DNA Damage / Q000235:genetics*; D056890:Eukaryota / Q000235:genetics*; D022761:Gene Transfer, Horizontal; D006801:Humans; D012098:Reproduction / Q000235:genetics*
chemical_list: D004247:DNA
keywords: anachronistic evolution; evolution; horizontal gene transfer; meiosis; natural transformation; sexual reproduction; short and degraded DNA