Background
Genetic diversity (GD) quantifies the variation of genes within species, variation which occurs within and among populations \citep{Hoban_2022}. GD therefore determines species’ resilience and evolutionary potential, e.g. their ability to adapt to changing environmental conditions \citep{Sgr__2010}. Higher GD within a species increases the chance of the species to adapt to new conditions. Inversely, lower GD within a species increases its risk of extinction \citep{Spielman_2004}. GD also plays an important role in maintaining a variety of biodiversity benefits to humanity such as ecosystem resilience, food, medicine, energy, culture, and well-being (see Des \citealp{Des_Roches_2021} for a review).
Phylogenetic diversity (PD) quantifies the evolutionary history captured by a set of species, as the sum of branch lengths connecting those species across the phylogenetic tree representing their evolutionary relationships \citep*{Faith_1992}. PD therefore represents the diversity of evolutionarily inherited features across the Tree of Life, which constitutes a reservoir of both current and yet-to-be discovered benefits for future generations – a notion referred to as biodiversity option value \citep*{ipbes2019}. PD can best be maintained through prioritising the conservation of evolutionarily distinct lineages to effectively safeguard the Tree of Life, such as the those highlighted within the EDGE (Evolutionarily Distinct and Globally Endangered) species framework \citep{Gumbs_2022}.
GD and PD respectively represent species’ evolutionary potential and history, and support most of the biodiversity benefits to humanity. Yet, these two biodiversity facets have been overlooked in previous biodiversity policies \citep{Cook_2017,Hoban_2021,Robuchon_2021}. Specifically, while PD was fully excluded from the strategic plan 2011-2020 of the Convention on Biological Diversity (CBD), GD was recognised (e.g. Aichi Target 13) but interpreted narrowly \citep{Hoban_2021}, mainly addressing GD of domesticated species (only a small fraction of all species). Moreover, many countries neglected to develop monitoring strategies with adequate indicators for GD and/or largely focused on ex situ conservation, overlooking in situ actions \citep{Hoban_2020}. This was partly due to the fact that the information regarding how (and why) to conserve and monitor GD in practice was inaccessible to policymakers and managers, and partly due to lack of GD indicators\citep{Cook_2017,Hoban_2021,Hoban_2013,R_Taylor_2017}. However, the situation has recently changed. For PD, the Intergovernmental Platform for Biodiversity and Ecosystem Services (IPBES) now recognises PD as an indicator of “maintenance of options” and “medicinal, biochemical and genetic resources” \citep{ipbes2019}. For GD, numerous recent advances in knowledge, technology, databases, practice, and capacity now make global commitments for conserving and monitoring GD feasible \citep{Hoban_2021a}. As the Parties to the Convention on Biological Diversity (CBD) plan to meet in December 2022 in Montréal to agree on a new post-2020 global biodiversity framework (GBF), we briefly analyse how GD and PD are currently considered in this new framework and discuss the opportunities this brings for strengthening their conservation.