Different rates of pollen and seed gene flow cause branch‐length and geographic cytonuclear discordance within Asian butternuts

Abstract We describe a method for comparing nuclear and organelle population differentiation (FST) in seed plants to test the hypothesis that pollen and seed gene flow rates are equal. Wright’s infinite island model is used, with arbitrary levels of self-fertilization and biparental organelle inheritance. The comparison can also be applied to gene flow in animals. Since effective population sizes are smaller for organelle genomes than for nuclear genomes and organelles are often uniparentally inherited, organelle FST is expected to be higher at equilibrium than nuclear FST even if pollen and seed gene flow rates are equal. To reject the null hypothesis of equal seed and pollen gene flow rates, nuclear and organelle FST’s must differ significantly from their expected values under this hypothesis. Finite island model simulations indicate that infinite island model expectations are not greatly biased by finite numbers of populations (≥100 subpopulations). The power to distinguish dissimilar rates of pollen and seed gene flow depends on confidence intervals for fixation index estimates, which shrink as more subpopulations and loci are sampled. Using data from the tropical tree Corythophora alta, we rejected the null hypothesis that seed and pollen gene flow rates are equal but cannot reject the alternative hypothesis that pollen gene flow is 200 times greater than seed gene flow.

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Great Wall blocks gene flow

Nature ◽

10.1038/news030414-3 ◽

2003 ◽

Author(s):

HelenR. Pilcher

Keyword(s):

Gene Flow ◽

Great Wall

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Differentiation and Interrelations of Two Representatives of Laudakia stellio Complex (Reptilia: Agamidae) in Israel

Russian Journal of Herpetology ◽

10.30906/1026-2296-1997-4-2-102-114 ◽

2011 ◽

Vol 4 (2) ◽

pp. 102-114 ◽

Cited By ~ 2

Author(s):

Evgenyi N. Panov ◽

Larissa Yu. Zykova

Keyword(s):

Population Structure ◽

Gene Flow ◽

Habitat Preference ◽

Additional Data ◽

Near East ◽

Field Studies ◽

Subspecies Level ◽

Limited Gene Flow ◽

Study Sites ◽

And Behavior

Field studies were conducted in Central Negev within the breeding range of Laudakia stellio brachydactyla and in NE Israel (Qyriat Shemona) in the range of an unnamed form (tentatively “Near-East Rock Agama”), during March – May 1996. Additional data have been collected in Jerusalem at a distance of ca. 110 km from the first and about 170 km from the second study sites. A total of 63 individuals were caught and examined. The animals were marked and their subsequent movements were followed. Social and signal behavior of both forms were described and compared. Lizards from Negev and Qyriat Shemona differ from each other sharply in external morphology, habitat preference, population structure, and behavior. The differences obviously exceed the subspecies level. At the same time, the lizards from Jerusalem tend to be intermediate morphologically between those from both above-named localities, which permits admitting the existence of a limited gene flow between lizard populations of Negev and northern Israel. The lizards from NE Israel apparently do not belong to the nominate subspecies of L. stellio and should be regarded as one more subspecies within the species.

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