Population Genomics for Insect Conservation

Abstract

Insects constitute vital components of ecosystems. There is alarming evidence for global declines in insect species diversity, abundance, and biomass caused by anthropogenic drivers such as habitat degradation or loss, agricultural practices, climate change, and environmental pollution. This raises important concerns about human food security and ecosystem functionality and calls for more research to assess insect population trends and identify threatened species and the causes of declines to inform conservation strategies. Analysis of genetic diversity is a powerful tool to address these goals, but so far animal conservation genetics research has focused strongly on endangered vertebrates, devoting less attention to invertebrates, such as insects, that constitute most biodiversity. Insects’ shorter generation times and larger population sizes likely necessitate different analytical methods and management strategies. The availability of high-quality reference genome assemblies enables population genomics to address several key issues. These include precise inference of past demographic fluctuations and recent declines, measurement of genetic load levels, delineation of evolutionarily significant units and cryptic species, and analysis of genetic adaptation to stressors. This enables identification of populations that are particularly vulnerable to future threats, considering their potential to adapt and evolve. We review the application of population genomics to insect conservation and the outlook for averting insect declines. Expected final online publication date for the Annual Review of Animal Biosciences, Volume 11 is February 2023. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

Less overall, but more of the same: drivers of insect population trends lead to community homogenization

“…dispersal rate) [ 24 ] and high thermal plasticity [ 45 ]. Genetically diverse species could also be at an advantage due to higher adaptability [ 46 ].…”

“…An important complement here is research on the plasticity and adaptive potential (e.g. genetic diversity) in different species [ 46 , 59 ]. In this context, we must keep in mind that abiotic and biotic conditions are dynamic and that the functional importance of a species may vary over time.…”

“…dispersal rate) [24] and high thermal plasticity [45]. Genetically diverse species could also be at an advantage due to higher adaptability [46]. These trait changes combined with an increase of generalists likely increases the risk of homogenization.…”

Incorporating genomics into insect conservation: Butterflies as a model group

“…In this section, we revisit key literature on butterfly population genomics with the aim of highlighting how their results and interpretation might be applied in future conservation actions (Table 1). The increasing availability of high‐quality reference genomes and the reducing costs of high‐throughput DNA sequencing have made genomics a more efficient tool for conservation biology (Allendorf et al, 2010; Formenti et al, 2022), which in the context of insect conservation might facilitate the discovery of species and estimation of genome‐wide diversity, population connectivity and local adaptation (Webster et al, 2022).…”

“…While the former is being tackled by initiatives that disseminate evidence‐based conservation actions (e.g., the Conservation Evidence project, https://www.conservationevidence.com/), the latter remains a major limitation given the rapid development of scientific tools but the slower pace of standardising methods that can be applied in real‐world conservation issues. For example, insect population genomics (i.e., the study of genome‐wide variation instead of a few loci) is a mature research field with a rich toolkit to study genome‐wide variation (Webster et al, 2022), but insect conservation practice has been rarely guided by genomic techniques.…”