How much do we know about the genetic diversity of plants endemic to the Alps?

Genetic diversity, a cornerstone of biodiversity, is fundamental for adaptation and the long-term survival of species. Here, we assess the current state of genetic research on the endemic flora of the European Alps. We identified 323 studies, of which only 61 studies showed some intraspecific genetic diversity. A Genetic Monitoring Effort Index (GME) was developed to quantify the depth of genetic knowledge per species and study, and used it to analyse monitoring trends. Our survey reveals that advancements in genetic techniques, such as high-throughput sequencing, have enabled continued improvement in genetic knowledge of endemic species, but pervasive knowledge deficits remain. This is striking, given that the European alpine flora has historically received considerable attention from scientists and botanists. Specifically, 78.8% of species have not been the subject of any genetic diversity study, and only 4.6% of species have had their genetic diversity assessed more than once. Additionally, we found that GME is positively associated with large-ranged taxa, pointing to the greater vulnerability and underrepresentation of narrow-ranged and micro-endemic species. In addition, very few taxa (9.5%) have been subject to a global IUCN conservation assessment. Our results demonstrate an urgent need to study the genetics of the alpine endemic flora in more detail. If this well-studied biodiversity hotspot is poorly known genetically, it is likely that other biodiversity hotspots have even greater knowledge deficits. Nextgen sequencing technologies promise a path toward rapid genetic knowledge gain, but the underlying fieldwork to obtain the specimens still needs to be done.