Dispersal predicts hybrid zone widths across animal diversity: Implications for species borders under incomplete reproductive isolation
Hybrid zones occur as range boundaries for many animal taxa. One model for how hybrid zones form and are stabilized is the tension zone model. This model predicts that hybrid zone widths are determined by a a balance between random dispersal into hybrid zones and selection against hybrids, and it does not formally account for local ecological gradients. Given the model's simplicity, it provides a useful starting point for examining variation in hybrid zone widths across animals. Here we examine whether random dispersal and a proxy for selection against hybrids (mtDNA distance) can explain variation in hybrid zone widths across 135 hybridizing taxon pairs. We show that dispersal explains >30% of hybrid zone width variation across animal diversity and that mtDNA distance explains little variation. Clade-specific analyses revealed idiosyncratic patterns. Dispersal and mtDNA distance predict hybrid zone widths especially well in reptiles, while hybrid zone width scaled positively with mtDNA distance in birds, opposite predictions. Lastly, the data suggest that lower bounds on hybrid zone widths may be set by dispersal and the extent of molecular divergence, suggesting that hybrid zones are unlikely to form in restricted geographic spaces in highly dispersive and/or recently diverged taxa. Overall, our analyses reinforce the fundamental importance of dispersal in hybrid zone formation, and more generally in the ecology of range boundaries.
- Downloaded 796 times
- Download rankings, all-time:
- Site-wide: 34,163
- In ecology: 726
- Year to date:
- Site-wide: 65,104
- Since beginning of last month:
- Site-wide: 77,152
Downloads over time
Distribution of downloads per paper, site-wide
- 27 Nov 2020: The website and API now include results pulled from medRxiv as well as bioRxiv.
- 18 Dec 2019: We're pleased to announce PanLingua, a new tool that enables you to search for machine-translated bioRxiv preprints using more than 100 different languages.
- 21 May 2019: PLOS Biology has published a community page about Rxivist.org and its design.
- 10 May 2019: The paper analyzing the Rxivist dataset has been published at eLife.
- 1 Mar 2019: We now have summary statistics about bioRxiv downloads and submissions.
- 8 Feb 2019: Data from Altmetric is now available on the Rxivist details page for every preprint. Look for the "donut" under the download metrics.
- 30 Jan 2019: preLights has featured the Rxivist preprint and written about our findings.
- 22 Jan 2019: Nature just published an article about Rxivist and our data.
- 13 Jan 2019: The Rxivist preprint is live!