Genetic structure of island and mainland populations of a Neotropical bumble bee species

Genetic structure of island and mainland populations of a Neotropical bumble bee species

Flavio O Francisco, Leandro R Santiago, Yuri M Mizusawa, Benjamin P Oldroyd, Maria C Arias

A note on the distribution of admixture segment lengths and ancestry proportions under pulse and two-wave admixture models

A note on the distribution of admixture segment lengths and ancestry proportions under pulse and two-wave admixture models

Shai Carmi, James Xue, Itsik Pe’er
(Submitted on 19 Sep 2015)

Admixed populations are formed by the merging of two or more ancestral populations, and the ancestry of each locus in an admixed genome derives from either source. Consider a simple “pulse” admixture model, where populations A and B merged t generations ago without subsequent gene flow. We derive the distribution of the proportion of an admixed chromosome that has A (or B) ancestry, as a function of the chromosome length L, t, and the initial contribution of the A source, m. We demonstrate that these results can be used for inference of the admixture parameters. For more complex admixture models, we derive an expression in Laplace space for the distribution of ancestry proportions that depends on having the distribution of the lengths of segments of each ancestry. We obtain explicit results for the special case of a “two-wave” admixture model, where population A contributed additional migrants in one of the generations between the present and the initial admixture event. Specifically, we derive formulas for the distribution of A and B segment lengths and numerical results for the distribution of ancestry proportions. We show that for recent admixture, data generated under a two-wave model can hardly be distinguished from that generated under a pulse model.

Sustained fitness gains and variability in fitness trajectories in the long-term evolution experiment with Escherichia coli

Sustained fitness gains and variability in fitness trajectories in the long-term evolution experiment with Escherichia coli

Richard E Lenski, Michael J Wiser, Noah Ribeck, Zachary D Blount, Joshua R Nahum, James Jeffrey Morris, Luis Zaman, Caroline B Turner, Brian D Wade, Rohan Maddamsetti, Alita R Burmeister, Elizabeth J Baird, Jay Bundy, Nkrumah A Grant, Kyle J Card, Maia Rowles, Kiyana Weatherspoon, Spiridon E Papoulis, Rachel Sullivan, Colleen Clark, Joseph S Mulka, Neerja Hajela

FINEMAP: Efficient variable selection using summary data from genome-wide association studies

FINEMAP: Efficient variable selection using summary data from genome-wide association studies

Christian Benner, Chris C.A. Spencer, Samuli Ripatti, Matti Pirinen

Speciation driven by hybridization and chromosomal plasticity in a wild yeast

Speciation driven by hybridization and chromosomal plasticity in a wild yeast

Jean-Baptiste Leducq, Lou Nielly-Thibault, Guillaume Charron, Chris Eberlein, Jukka-Pekka Verta, Pedram Samani, Kayla Sylvester, Chris Todd Hittinger, Graham Bell, Christian R Landry

Utilization of high throughput genome sequencing technology for large scale single nucleotide polymorphism discovery in red deer and Canadian elk

Utilization of high throughput genome sequencing technology for large scale single nucleotide polymorphism discovery in red deer and Canadian elk

Rudiger Brauning, Paul J Fisher, Alan F McCulloch, Russell J Smithies, James F Ward, Matthew J Bixley, Cindy T Lawley, Suzanne J Rowe, John C McEwan

Social selection parapatry in an Afrotropical sunbird

Social selection parapatry in an Afrotropical sunbird

Jay P McEntee, Joshua Penalba, Chacha Werema, Elia Mulungu, Maneno Mbilinyi, David Moyer, Louis Hansen, Jon Fjeldsaa, Rauri C.K. Bowie