10.5061/DRYAD.T76HDR837
Rosche, Christoph
0000-0002-4257-3072
Martin Luther University Halle-Wittenberg
Baasch, Annnett
Anhalt University of Applied Sciences
Runge, Karen
Anhalt University of Applied Sciences
Brade, Philipp
Anhalt University of Applied Sciences
Träger, Sabrina
Martin Luther University Halle-Wittenberg
Parisod, Christian
University of Fribourg
Hensen, Isabell
Martin Luther University Halle-Wittenberg
Data from: Tracking population genetic signatures of local extinction with
herbarium specimens
Dryad
dataset
2022
microsatellites genotypes
historical DNA
genetic diversity and differentiation
herbarium specimens
Conservation genetics
FOS: Biological sciences
ELER regulation*
1303/2013
2022-04-29T00:00:00Z
2022-04-29T00:00:00Z
en
50816 bytes
3
CC0 1.0 Universal (CC0 1.0) Public Domain Dedication
Background and Aims Habitat degradation and landscape fragmentation
dramatically lower population sizes of rare plant species. Decreasing
population sizes may, in turn, negatively affect genetic diversity and
reproductive fitness which can ultimately lead to local extinction of
populations. Although such extinction vortex dynamics have been postulated
in theory and modelling for decades, empirical evidence from local
extinctions of plant populations is scarce. In particular, comparisons
between current vs. historical genetic diversity and differentiation are
lacking despite their potential to guide conservation management. Methods
We studied the population genetic signatures of the local extinction of
Biscutella laevigata subsp. gracilis populations in Central Germany. We
used microsatellites to genotype individuals from 15 current populations,
one ex-situ population, and 81 herbarium samples from five extant and 22
extinct populations. In the current populations, we recorded population
size and fitness proxies, collected seeds for a germination trial and
conducted a vegetation survey. The latter served as surrogate for habitat
conditions to study how habitat dissimilarity affects functional
connectivity among the current populations. Key Results Bayesian
clustering revealed similar gene pool distribution in current and
historical samples but also indicated that a distinct genetic cluster was
significantly associated with extinction probability. Gene flow was
affected by both spatial distance and floristic composition of population
sites, highlighting the potential of floristic composition as powerful
predictor of functional connectivity which may promote decision making for
reintroduction measures. For an extinct population, we found a negative
relationship between sampling year and heterozygosity. Inbreeding
negatively affected germination. Conclusions Our study illustrates the
usefulness of historical DNA to study extinction vortices in threatened
species. Our novel combination of classical population genetics together
with data from herbarium specimens, an ex-situ population and a
germination trial underscores the need for genetic rescue measures to
prevent extinction of B. laevigata in Central Germany.