Ricerc@Sapienza

Socotra Island, in the western Indian Ocean, harbors high biodiversity and endemism and makes up the largest part of the Socotra archipelago UNESCO World Heritage site. Its climatic, pedological, and geomorphological characteristics, together with the long geological isolation and inaccessibility, led to the flourishing of unique tree diversity, with great cultural and ecological value. Lately, trees on Socotra are facing new threats linked to the abandonment of traditional management practices, climate change impacts, and growing human pressure.

Phenotypic plasticity is generally explained as the result of epigenetic mechanisms modifying gene expression in response to changing environmental conditions. However, the biology of transposable elements (TEs) suggests that such elements may also induce differential gene expression by affecting regulatory regions. We discuss the ecological and evolutionary relevance of epigenetic modifications versus transposon activity, taking into account that epigenetic modifications are generally reversible but that the modifications induced by TEs are stably inherited.