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USGS · 70231203

Genome-wide SNP analysis reveals multiple paternity in Burmese pythons invasive to the Greater Florida Everglades

Abstract

Reproductive strategies are an essential component of invasion ecology that influence invasion success and rates of population growth. Burmese Pythons ( Python bivittatus ) are large constrictor snakes that were introduced to the Greater Everglades Ecosystem of southern Florida, USA, from Asia. Since their introduction, these giant constrictors have spread throughout wetlands of southern Florida while increasing in abundance and causing declines in the native species upon which they prey. Multiple paternity in reproduction could facilitate invasion success by increasing the genetic diversity produced within each reproductive event. We used Diversity Arrays Technology genome-wide genotyping to assess multiple paternity in the progeny of wild Burmese Pythons in Florida. We analyzed >4,000 single nucleotide polymorphisms from 153 neonates belonging to 4 clutches collected in southwestern Florida. Complementary hierarchical and K -means clustering analyses of the genetic distances within clutches revealed that three clutches were each fertilized by two sires, with a fourth fertilized by a single sire. The proportions of offspring attributable to each sire within multiple paternity clutches ranged from nearly even to highly skewed. Analysis of multivariate dispersion showed significantly increased genetic variability in the multiple paternity clutches. These results improve our understanding of the reproductive strategy and invasion potential of a giant constrictor with significant ecological impacts.

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90° N90° S · 180° W ← longitude → 180° E
Source-reported bounding extent: 25.005972656239187° to 27.039556602163195° latitude; -82.24365234375° to -79.4970703125° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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BibTeXRIS

James Skelton, Ian A. Bartoszek, Caitlin Beaver, Kristen Hart, Margaret Hunter. 2021. Genome-wide SNP analysis reveals multiple paternity in Burmese pythons invasive to the Greater Florida Everglades. https://doi.org/10.1670/20-104

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