DFG_ICIPS

Early land plants have met the challenge of continuous range expansion, further away from water, always at risk of dehydration. Consequently, also the sexual reproduction of land plants is geared towards independency of water. Several key innovations in sexual reproduction originated in the land plant lineage, such as spores with a rigid outer surface, ovules harboring reduced female gametophytes and a multicellular embryo that is dispersed within seeds in a dehydrated state. Hence, the evolution of sexual reproduction in land plants provides stunning examples for the crucial biological concepts of "innovation" (e.g., origin of new reproductive structures such as ovules and flowers), and "coevolution" (e.g., between signalling peptides and receptors involved in fertilization). The evolutionary dynamics and molecular mechanisms underlying these processes are only poorly understood.