Conservation of adaptive potential and functional diversity: integrating old and new approaches

Abstract

Continuing advances in whole genome scale approaches integrated with other 'omic' technologies promise to revolutionise understanding about the relevance of genetic variation to risks of species declines and extinctions. In the face of the vastly increased accessibility of such approaches, it is important that we advance beyond descriptive genetics to developing a more functional perspective on whether enhancing genetic variation is the most effective strategy for conservation management. Rather than a comprehensive review of the field, this paper focuses on several key issues that have been discussed since the dawn of "conservation genetics" and that warrant re-assessment based on emerging "omics" data, combined with new analytical approaches to ecological niche modelling and population genomic analyses. Specifically, the following interrelated issues are discussed: (1) the relative impacts of inbreeding and outbreeding on fitness and adaptive potential, particularly in relation to genetic rescue; (2) how "species" should be defined for conservation management; (3) deciding on how much and what type of genetic variation should be preserved; and (4) how we can move from descriptive genetics to actually understanding adaptive processes in the wild. None of the ideas presented are new; the purpose here is to serve as a reminder that many of the issues raised 30 years ago are still relevant but not completely resolved and would benefit from tackling afresh with modern tools, but considering historical perspectives.

Conservation of adaptive potential and functional diversity

“…Another presentation reviewed the importance and potential for measuring both adaptive and deleterious variation in threatened populations (see Freedman et al 2016). In the special issue Mable (2019) acknowledges the importance of genomic methods towards the conservation of adaptive potential, but suggests that integration with ecological methods and concepts remains essential. She stresses the importance of work towards understanding adaptive processes, beyond merely descriptive data.…”

Population genomics reveals lack of greater white-fronted introgression into the Swedish lesser white-fronted goose

“…It should be noted here that the LWfG as a species has one of the highest levels of genetic diversity among birds 39 , 40 . Nonetheless, the comparatively lower diversity in the Swedish population signifies a reduced potential to adapt to changes in the environment 41 . Also, the increased amount of inbreeding in the Swedish population, and in particular the excess of long RoHs observed in our analyses, suggest that the Swedish population has been subject to recent mating between close relatives 42 , 43 , which may be explained by a generally small population size and/or significant influence from the captive breeding programme.…”

Giraffe taxonomy, geographic distribution and conservation

“…The IUCN definition of a species is provided online: ‘A group of interbreeding individuals with common characteristics that produce fertile (capable of reproducing) offspring and which are not able to interbreed with other such groups, that is, a population that is reproductively isolated from others’ (https://www.iucn.org/downloads/en_iucn_glossary_definitions.pdf), which is essentially the BSC. Given discrepancies in defining ‘species’, some scientists have suggested that conservation biology would benefit the most by concentrating on assessing the adaptive potential of evolutionary significant units rather than engage in mental gymnastics about ‘species’ (Fraser & Bernatchez, 2001; Funk, McKay, Hohenlohe, & Allendorf, 2012; Mable, 2019; Stanton et al., 2019).…”