The Limits to Adaptation in Restored Ecosystems and How Management Can Help Overcome Them

Abstract

Adaptation drives the diversity of form and function observed in nature and is key to population persistence. Yet, adaptation can be limited by a lack of genetic variation, trade-offs, small population size, and constraints imposed by coevolving interacting species. These limits may be particularly important to the colonizing populations in restored ecosystems, such as native prairies restored through seed sowing. Here, we discuss how constraints to adaptation are likely to play out in restored prairie ecosystems and how management decisions, such as seed mix composition, prescribed fire, and strategic site selection, might be used to overcome some of these constraints. Although data are still limited, recent work suggests that restored prairie populations likely face strong selection and that promoting the potential for adaptation in these systems may be necessary for restoring populations both now and in the face of further global change. 1 We thank Bill Schneider and an anonymous reviewer for providing thoughtful feedback on an earlier version of this manuscript and the organizers, speakers, and attendees of the 65th Annual Syposium at the Missouri Botanical Garden for numerous thoughtful comments that helped refine the ideas presented here. This work was funded by National Science Foundation (NSF) DEB-1547961 awarded to J. A. L. and L. A. B. and by NSF DDIG DEB-1701791 awarded on behalf of S. M. M. to J. A. L.

Linking genetic diversity and species diversity through plant–soil feedback

“…For each of these species we used two populations: one from the southern Midwestern United States (South; Coreopsis , Missouri Wildflower Nursery, originally collected from Joplin County, Missouri, USA; Echinacea , Hamilton Native Outpost, cultivated in Putnam County, Missouri, USA but likely originating from populations in Iowa) and one from the upper Midwestern United States (North; Coreopsis , Agrecol, originally collected from Kenosha, Wisconsin, USA; Echinacea , Agrecol, originally collected from Madison, Iowa, USA). These populations differ in several traits, including relative growth rate, supporting our assumption that genetic distances are greater between than within populations (Lau et al, 2019; Zirbel & Brudvig, 2020a, 2020b; Appendix S1: Table S1).…”

Evolution during seed production for ecological restoration? A molecular analysis of 19 species finds only minor genomic changes

“…random changes in allele frequency and loss of genetic variability. Populations may also randomly accumulate alleles that reduce adaptation to natural environments (Pertoldi et al 2007;Lau et al 2019). The loss of genetic variability would be particularly problematic because 4 standing genetic variation is a necessary prerequisite for rapid adaptation (Crowe & Parker 2008).…”

Rapid adaptation (or not) in restored plant populations

“…In the case of plants, seeds can be saved to compare established populations to their original source to test for evidence of adaptation (Franks, Avise, Bradshaw, Conner, & Etterson, 2008). A demographic boost due to rapid adaptation might also be particularly important to the success of restorations (LaRue et al, 2017), especially because populations sown during restoration may be maladapted as they often come from nonlocal sources (Gallagher & Wagenius, 2016; Vander Mijnsbrugge, Bischoff, & Smith, 2010) and/or are sown into degraded, anthropogenically disturbed environments (Lau, Magnoli, Zirbel, & Brudvig, 2019; Suding, 2011). To test for evidence of rapid adaptation in recently established plant populations in restorations, I capitalized on an experiment in which two former agricultural fields were restored to prairie using identical seed mixes.…”