International audienceAim Biodiversity hot-spots are regions containing evolutionary heritage from ancient or recent geological epochs, i.e. evolutionary ‘museums’ or ‘cradles’, respectively. We hypothesize that: (1) there are also ‘museums’ and ‘cradles’ within regions – some species pools of particular habitat types contain angiosperm (flowering plants) lineages from ancient geological epochs, others from recent epochs; (2) habitat-specific abiotic factors control the number of angiosperm lineages from a given epoch contained in a given habitat species pool. Location The flora of the Netherlands. Methods We studied the world's largest vegetation-plot database and a new, uniquely resolved dated angiosperm phylogeny available for the Netherlands. We characterized species pools of habitat types by a novel concept: epoch-specific lineage diversities. Results We found that species pools of most habitat types were characterized by over- or underrepresentation of lineages from at least one epoch, dating back to the origin of angiosperms. These patterns are not captured by mean lineage ages. Abiotic environments explained on average 56% and up to 75% of the variance in the number of lineages per epoch, but with opposing effects of the same factor for different epochs. Specifically, warm and dry habitats tend to contain lineages dating back to warm and dry epochs. Identifying lineages from sets of random time intervals rather than from a set of geological epochs significantly reduced relationships with the environment. Main conclusions Within a region, habitat types differ significantly in the evolutionary heritage they contain from different geological epochs, and these differences are controlled by the environmen

Present biodiversity comprises the evolutionary heritage of Earth's epochs. Lineages from particular epochs are often found in particular habitats, but whether current habitat decline threatens the heritage from particular epochs is unknown. We hypothesized that within a given region, humans threaten specifically habitats that harbor lineages from a particular geological epoch. We expect so because humans threaten environments that dominated and lineages that diversified during these epochs. We devised a new approach to quantify, per habitat type, diversification of lineages from different epochs. For Netherlands, one of the floristically and ecologically best-studied regions, we quantified the decline of habitat types and species in the past century. We defined habitat types based on vegetation classification and used existing ranking of decline of vegetation classes and species. Currently, most declining habitat types and the group of red-listed species are characterized by increased diversification of lineages dating back to Paleogene, specifically to Paleocene-Eocene and Oligocene. Among vulnerable habitat types with large representation of lineages from these epochs were sublittoral and eulittoral zones of temperate seas and 2 types of nutrient-poor, open habitats. These losses of evolutionary heritage would go unnoticed with classical measures of evolutionary diversity. Loss of heritage from Paleocene-Eocene became unrelated to decline once low competition, shade tolerance, and low proportion of non-Apiaceae were accounted for, suggesting that these variables explain the loss of heritage from Paleocene-Eocene. Losses of heritage from Oligocene were partly explained by decline of habitat types occupied by weak competitors and shade-tolerant species. Our results suggest a so-far unappreciated human threat to evolutionary heritage: habitat decline threatens descendants from particular epochs. If the trends persist into the future uncontrolled, there may be no habitats within the region for many descendants of evolutionary ancient epochs, such as Paleogene.

Premise Plant lineages differ markedly in species richness globally, regionally, and locally. Differences in whole‐genome characteristics (WGCs) such as monoploid chromosome number, genome size, and ploidy level may explain differences in global species richness through speciation or global extinction. However, it is unknown whether WGCs drive species richness within lineages also in a recent, postglacial regional flora or in local plant communities through local extinction or colonization and regional species turnover. Methods We tested for relationships between WGCs and richness of angiosperm families across the Netherlands/Germany/Czechia as a region, and within 193,449 local vegetation plots. Results Families that are species‐rich across the region have lower ploidy levels and small monoploid chromosomes numbers or both (interaction terms), but the relationships disappear after accounting for continental and local richness of families. Families that are species‐rich within occupied localities have small numbers of polyploidy and monoploid chromosome numbers or both, independent of their own regional richness and the local richness of all other locally co‐occurring species in the plots. Relationships between WGCs and family species‐richness persisted after accounting for niche characteristics and life histories. Conclusions Families that have few chromosomes, either monoploid or holoploid, succeed in maintaining many species in local communities and across a continent and, as indirect consequence of both, across a region. We suggest evolutionary mechanisms to explain how small chromosome numbers and ploidy levels might decrease rates of local extinction and increase rates of colonization. The genome of a macroevolutionary lineage may ultimately control whether its species can ecologically coexist.