bio

Horizontal gene transfer

Genetic material moving between organisms outside reproduction — sideways rather than down a lineage. That it is common in bacteria is well known; less often mentioned is that it happens in plants too, and sometimes consequentially. The shrub *Amborella trichopoda*, which sits at the base of the flowering plant tree, has taken in five entire foreign mitochondrial genomes from mosses, green algae and other flowering plants by direct contact. Ferns borrowed a light receptor called neochrome from hornworts about 180 million years ago and used it to photosynthesise better in deep shade.