Thread by @MExpositoAlonso

Our paper "Genetic diversity loss in the Anthropocene" is out in @ScienceMagazine!

We study how genetic diversity is lost by habitat loss to help define @UNBiodiversity #Sustainable targets

science.org/doi/10.1126/sc…

@carnegiescience
@CarnegiePlants
@CarnegieEcology
@Stanford

This all started with a deep worry about our lack of knowledge of global losses of genetic diversity and the call for more conservation policies that account for genetics @LindaLaikre, @seanmhoban, and others

in summer 2021, a new @UN press release (motivated by a piece by @sdiazecology 10.1126/science.abe1530) presented the goal to preserve “at least 90% of genetic diversity within all species”. Great news, but how do we get there and measure progress?
un.org/sustainabledev…

The direct approach to track progress should work: we SEQUENCE ALL THE GENOMES and track genetic diversity over time, but empirical studies show shy signals (Leight et al Evo App, @KatieMillette et al Eco Letter). Perhaps there's not enough genomic and temporal data yet?

Instead, we tried to think of first principles: how genetic diversity within a species is related to habitat size?
We then described the mutations-area relationship (MAR) using the 1001 Genomes of Arabidopsis (#arabidopsislove)

We did lots of computer simulations to see if such a simple mathematical relationship could predict losses of genetic diversity if we know how much habitat is removed in our simulations ... it worked!

We then downloaded a s*** ton of genomes from other species 🦏 🌲🌳🦤🐭🐺🪰🌾🌴🌸 and saw good fit with MAR!

So could we use this method to provide a data-driven target for. the @UNBiodiversity #SustainableDevelopment goals?

We though of several back-of-the-envelope calculations, e.g. using global area transformations, from @IPBES, which is ~40% of Earth (@globalforests loss map below)

The using MAR and land data we back-calculated genetic loss, suggesting an average already over 10%.

But this is approximate and we still do not understand well the uncertainty of these methods ... we lack data from so many species!

+ a single estimate is not too helpful when many species have lost close to 0% and others have lost 100%, so instead we study variability in genetic diversity losses

Many threatened species must have lost a lot (>>10%) based on habitat loss, and it will keep ongoing @moldotorg

This may read daunting, but we can ACT NOW. @UNBiodiversity should make bold plans to protecting populations and genetic variation of species to ensure long-term evolution and adaptation

And we all--ecologists, geneticists, evo biologists--even working on basic science can help improve these methods and better protect nature!
Please reach out with ideas to improve

🙏thankful to our lab's team @LucCzech @leg2015 @s_hateley @laura_leventhal @MeganRRuffley seba @ZessingAround and fantastic collaborators @TomBooker12 @ChrisKyriazis @plantricia @Noguesbravo @VPagowski @spence_jeffrey_ @clw_gg

& 🙏 thanks @markabelan for artistic cover!