The impact of human-made ecological changes on the genetic architecture of Daphnia species.
The overenrichment (eutrophication) of aquatic ecosystems with nutrients leading to algal blooms and anoxic conditions has been a persistent and widespread environmental problem. Although there are many studies on the ecological impact of elevated phosphorus (P) levels (e.g., decrease in biodiversity and water quality), little is known about the evolutionary consequences for animal species. We reconstructed the genetic architecture of a Daphnia species complex in 2 European lakes using diapausing eggs that were isolated from sediment layers covering the past 100 years. Changes in total P were clearly associated with a shift in species composition and the population structure of evolutionary lineages. Although environmental conditions were largely re-established after peak eutrophication during the 1970s and 1980s, original species composition and the genetic architecture of species were not restored but evolved along new evolutionary trajectories. Our data demonstrate that anthropogenically induced temporal alterations of habitats are associated with long-lasting changes in communities and species via interspecific hybridization and introgression.
Brede
Nora
N
Department of Ecology and Evolution, Goethe-University Frankfurt am Main, Siesmayerstrasse 70, D-60054 Frankfurt am Main, Germany.
Sandrock
Christoph
C
Straile
Dietmar
D
Spaak
Piet
P
Jankowski
Thomas
T
Streit
Bruno
B
Schwenk
Klaus
K
D000818:Animals; D004272:DNA, Mitochondrial / Q000235:genetics; D003621:Daphnia / Q000235:genetics*; D055669:Ecological and Environmental Phenomena; D005060:Europe; D005068:Eutrophication; D005618:Fresh Water; D005838:Genotype; D006801:Humans; D013997:Time Factors
D004272:DNA, Mitochondrial