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Abstract Hybridization is a common process that has broadly impacted the evolution of multicellular eukaryotes; however, how ecological factors influence this process remains poorly understood. Here, we report the findings of a 3-year recapture study of the Bryant’s woodrat (Neotoma bryanti) and desert woodrat (Neotoma lepida), two species that hybridize within a creosote bush (Larrea tridentata) shrubland in Whitewater, CA, USA. We used a genotype-by-sequencing approach to characterize the ancestry distribution of individuals across this hybrid zone coupled with Cormack–Jolly–Seber modeling to describe demography. We identified a high frequency of hybridization at this site with ~40% of individuals possessing admixed ancestry, which is the result of multigenerational backcrossing and advanced hybrid-hybrid crossing. F1, F2, and advanced generation hybrids had apparent survival rates similar to parental N. bryanti, while parental and backcross N. lepida had lower apparent survival rates and were far less abundant. Compared to bimodal hybrid zones where hybrids are often rare and selected against, we find that hybrids at Whitewater are common and have comparable survival to the dominant parental species, N. bryanti. The frequency of hybridization at Whitewater is therefore likely limited by the abundance of the less common parental species, N. lepida, rather than selection against hybrids.
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Democracy, aid, and diffusion: A normative approach to the hybrid regime
Abstract Despite its increased prioritization over the past several decades, democracy remains an elusive feat for many nations. This is due, in part, to a recent uptick in hybrid regimes, which possess qualities of both democracy and authoritarianism simultaneously. Among others, one especially salient explanation for hybrid formation is democracy aid itself, which often engenders superficial democratization while masking ongoing authoritarian practices. Still, despite considerable research examining how various factors—including aid—impact hybrid regimes, relatively little headway has been made. This is due primarily to continued disagreement over how to best measure and situate hybrids within the broader democracy literature. In this review, I demonstrate the role sociology can play in addressing this issue while advancing research on democracy, hybrids, and aid in a productive way. I argue that using sociological theories explaining the spread of global norms—such as democracy—to analyze hybrid regimes will facilitate improved understanding of democracy and the factors which shape it across the social sciences.
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- Award ID(s):
- 2001915
- PAR ID:
- 10381480
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Sociology Compass
- Volume:
- 14
- Issue:
- 12
- ISSN:
- 1751-9020
- Format(s):
- Medium: X Size: p. 1-16
- Size(s):
- p. 1-16
- Sponsoring Org:
- National Science Foundation
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