Survival at geographic range edges, where organisms are often at the limits of their physiological tolerances, can trigger unusual responses in reproduction.
Sinclair et al. describe the first observations of pseudoviviparous shoots in the marine angiosperm, Posidonia australis. Unfertilized flowers cheated and ‘switched’ to plantlet development. Multilocus genotypes showed these plantlets were genetically identical to their maternal parent. However, additional alleles in many genotypes were detected, suggesting somatic mutations or hybridization events. Low genetic diversity and failed sexual reproduction suggest both genetic and ecological constraints limit the ability of this meadow to adapt or range shift under changing climate regimes.