A century-long genetic record reveals that protist effective population sizes are comparable to those of macroscopic species

TY - JOUR

T1 - A century-long genetic record reveals that protist effective population sizes are comparable to those of macroscopic species

AU - Watts, Phillip C.

AU - Lundholm, Nina

AU - Ribeiro, Sofia

AU - Ellegaard, Marianne

PY - 2013/12/23

Y1 - 2013/12/23

N2 - Effective population size (Ne) determines the rate of genetic drift and the relative influence of selection over random genetic changes. While free-living protist populations characteristically consist of huge numbers of cells (N), the absence of any estimates of contemporary Ne raises the question whether protist effective population sizes are comparably large. Using microsatellite genotype data of strains derived from revived cysts of the marine dinoflagellate Pentapharsodinium dalei from sections of a sediment record that spanned some 100 years, we present the first estimates of contemporary Ne for a local population in a free-living protist. The estimates of Ne are relatively small, of the order of a few100 individuals, and thus are similar in magnitude to values of Ne reported for multicellular animals: the implications are that Ne of P. dalei is of many orders of magnitude lower than the number of cells present (Ne/N ~ 10-12) and that stochastic genetic processes may be more prevalent in protist populations than previously anticipated.

AB - Effective population size (Ne) determines the rate of genetic drift and the relative influence of selection over random genetic changes. While free-living protist populations characteristically consist of huge numbers of cells (N), the absence of any estimates of contemporary Ne raises the question whether protist effective population sizes are comparably large. Using microsatellite genotype data of strains derived from revived cysts of the marine dinoflagellate Pentapharsodinium dalei from sections of a sediment record that spanned some 100 years, we present the first estimates of contemporary Ne for a local population in a free-living protist. The estimates of Ne are relatively small, of the order of a few100 individuals, and thus are similar in magnitude to values of Ne reported for multicellular animals: the implications are that Ne of P. dalei is of many orders of magnitude lower than the number of cells present (Ne/N ~ 10-12) and that stochastic genetic processes may be more prevalent in protist populations than previously anticipated.

U2 - 10.1098/rsbl.2013.0849

DO - 10.1098/rsbl.2013.0849

M3 - Letter

C2 - 24284562

SN - 1744-9561

VL - 9

JO - Biology Letters

JF - Biology Letters

IS - 6

M1 - 20130849

ER -