{"scopus_import":"1","pmid":1,"quality_controlled":"1","abstract":[{"text":"The F5 (2n = 34) and FM2 (2n = 44-46) chromosome races of the Sceloporus grammicus complex form a parapatric hybrid zone in the Mexican state of Hidalgo, characterized by steep concordant clines among three diagnostic chromosome markers across a straight-line distance of about 2 km. Here, we show that this zone is actually structured into local patches in which hybridization extends over an extremely irregular front. The distribution of hybrid-index (HI) scores across the transect reveals some hybridization at almost all localities mapped in a central 7 km x 3 km area. Pooling the central samples produces both a strong heterozygote deficit for all diagnostic markers and strong linkage disequilibria between all pairwise combinations of these (unlinked) markers. Moreover, a highly significant association exists between the habitat on which each individual was caught and its karyotype (F5 chromosomes are more likely to be found on oak). Analysis of genotype frequencies over a range of spatial scales shows that there is no significant heterozygote deficit or habitat association within local areas of less than about 200 m; however, there is significant linkage disequilibrium over the smallest scales (R = D (pquv)1/2 = 0.29, support limits, 0.18-0.36) over 100 m. These patterns suggest that lizards mate and choose habitats randomly within local patches. This conclusion is supported by mark-recapture estimates of dispersal (≈ 80 m in a generation) and by inference of matings from embryo and maternal karyotypes. Closer examination of the two-dimensional pattern reveals a convoluted cline for all three markers, with a width of 830 m (support limits 770 m-930 m). This cline width, combined with the strength of local linkage disequilibrium, implies a dispersal rate of σ = 160 m in a generation and an effective selection pressure of 30% on each chromosome marker. The proportion of inviable embryos is greater in females from the center of the hybrid zone; this is caused by effects associated with both karyotype and location. The hybrid zone is likely to be maintained by selection against chromosomal heterozygotes, by other kinds of selection against hybrids, and by selection adapting the chromosome races to different habitats. The structure of the contact may be caused by both random drift and by selection in relation to habitat.","lang":"eng"}],"author":[{"full_name":"Sites, Jack","last_name":"Sites","first_name":"Jack"},{"last_name":"Barton","full_name":"Barton, Nicholas H","orcid":"0000-0002-8548-5240","id":"4880FE40-F248-11E8-B48F-1D18A9856A87","first_name":"Nicholas H"},{"first_name":"Kent","full_name":"Reed, Kent","last_name":"Reed"}],"citation":{"apa":"Sites, J., Barton, N. H., & Reed, K. (1995). The genetic structure of a mosaic hybrid zone between two chromosome races of the Sceloporus grammicus complex (Sauria, Phrynosomatidae) in central Mexico. Evolution. Wiley-Blackwell. https://doi.org/10.1111/j.1558-5646.1995.tb05955.x","mla":"Sites, Jack, et al. “The Genetic Structure of a Mosaic Hybrid Zone between Two Chromosome Races of the Sceloporus Grammicus Complex (Sauria, Phrynosomatidae) in Central Mexico.” Evolution, vol. 49, no. 1, Wiley-Blackwell, 1995, pp. 9–36, doi:10.1111/j.1558-5646.1995.tb05955.x.","ieee":"J. Sites, N. H. Barton, and K. Reed, “The genetic structure of a mosaic hybrid zone between two chromosome races of the Sceloporus grammicus complex (Sauria, Phrynosomatidae) in central Mexico,” Evolution, vol. 49, no. 1. Wiley-Blackwell, pp. 9–36, 1995.","chicago":"Sites, Jack, Nicholas H Barton, and Kent Reed. “The Genetic Structure of a Mosaic Hybrid Zone between Two Chromosome Races of the Sceloporus Grammicus Complex (Sauria, Phrynosomatidae) in Central Mexico.” Evolution. Wiley-Blackwell, 1995. https://doi.org/10.1111/j.1558-5646.1995.tb05955.x.","ama":"Sites J, Barton NH, Reed K. The genetic structure of a mosaic hybrid zone between two chromosome races of the Sceloporus grammicus complex (Sauria, Phrynosomatidae) in central Mexico. Evolution. 1995;49(1):9-36. doi:10.1111/j.1558-5646.1995.tb05955.x","short":"J. Sites, N.H. Barton, K. Reed, Evolution 49 (1995) 9–36.","ista":"Sites J, Barton NH, Reed K. 1995. The genetic structure of a mosaic hybrid zone between two chromosome races of the Sceloporus grammicus complex (Sauria, Phrynosomatidae) in central Mexico. Evolution. 49(1), 9–36."},"intvolume":" 49","extern":"1","title":"The genetic structure of a mosaic hybrid zone between two chromosome races of the Sceloporus grammicus complex (Sauria, Phrynosomatidae) in central Mexico","status":"public","month":"02","type":"journal_article","publication_identifier":{"issn":["0014-3820"]},"article_processing_charge":"No","user_id":"ea97e931-d5af-11eb-85d4-e6957dddbf17","article_type":"original","oa_version":"Published Version","date_created":"2018-12-11T12:08:06Z","date_published":"1995-02-01T00:00:00Z","main_file_link":[{"open_access":"1","url":"https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1558-5646.1995.tb05955.x"}],"date_updated":"2022-06-13T09:24:40Z","_id":"4297","publication":"Evolution","publist_id":"1779","issue":"1","doi":"10.1111/j.1558-5646.1995.tb05955.x","acknowledgement":"For field assistance in collecting and mapping of the zone, we thank E. Arevalo, I. Goyenechea, D. Hutchison, M. Man- cilia, F. Mendoza, D. Mink, and J. and H. Sites. The mark- recapture work was carried out by M. Mancilla, F Mendoza, and A. Gonzales. J.W.S. also thanks T. Hinckley and D. Ste­vens of the Brigham Young University Department of Ge­ography for lessons in surveying and map making and use of the field equipment and planimeter. B. Nürnberger pro­vided the digitized coordinates for individual lizards and as­sisted with the analysis of spatial structure and viability. B. Nürnberger, C. MacCallum, J. Mallet, and J. Searle also pro­vided helpful comments on the manuscript. This work was supported by National Science Foundation grants BSR 85- 09092 and 88-22751 to J.W.S., and grants from the Science and Engineering Research Council (GR/H09929) and Natural Environment Research Council (GR3/8002) and the DarwinTrust to N.H.B. The Mexican agency Secretaria de DesarrolloUrbano y Ecologia (now Secretaria de Desarrollo Social) kindly provided scientific collecting permits (to E. Arévalo) for field work in 1989 and 1991.","page":"9 - 36","publication_status":"published","external_id":{"pmid":["28593667"]},"publisher":"Wiley-Blackwell","volume":49,"year":"1995","day":"01","oa":1,"language":[{"iso":"eng"}]}