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@jeffspence.github.io

We are destroying species' habitats, leading to a mass extinction event. This habitat destruction also reduces the genetic diversity _within_ species. Our latest work develops quantitative models to predict how much genetic diversity has been and _will be_ lost. 🧬🧪🧵 www.pnas.org/doi/10.1073/...

pnas.orgLarge future genetic diversity losses are predicted from conservation indicators even with habitat protection | PNASGenetic diversity within species underpins evolutionary adaptation and has recently been included as a target for protection in the United Nations’...

31/3/26, 4:27 am30 reposts60 likes

Jeff Spence

@jeffspence.github.io

31 Mar

We started with a simple question: What happens to genetic diversity when part of a species' habitat suddenly become uninhabitable?

Jeff Spence

@jeffspence.github.io

31 Mar

To answer this, we developed WFmoments, a suite of numerical tools for computing things like π and Fst under arbitrary multi-deme Wright-Fisher models. We complemented this theory with more realistic continuous space SLiM simulations. github.com/moiexpositoalonsolab/wfmoments

github.comGitHub - moiexpositoalonsolab/wfmomentsContribute to moiexpositoalonsolab/wfmoments development by creating an account on GitHub.

Jeff Spence

@jeffspence.github.io

31 Mar

What we found surprised us... Species can lose A LOT of habitat without having much effect on genetic diversity. In some scenarios a species can lose 80% of its habitat while retaining 90% of its genetic diversity. But this is just IN THE SHORT TERM.

Jeff Spence

@jeffspence.github.io

31 Mar

It can take thousands of generations for the full effects of habitat loss to be felt in terms of genetic diversity. In the long run even small reductions in habitable area can result in large reductions in genetic diversity.

Jeffrey Ross-Ibarra

@jrossibarra.bsky.social

31 Mar

Hi Jeff, interested in checking this out. Confused as to whether there is something different going on other than 1) π is driven by intermediate freq. alleles, so even big changes in N won't affect it in short term and 2) independent drift in isolated pops causes metapop Ne > sum of individual Nes.

Jeff Spence

@jeffspence.github.io

31 Mar

Yes! That’s basically the gist. There’s some effect of the geometry of the habitat, and the spatial structure of how habitat is lost, but what you said is the right intuition.