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Reposted by Jordan S. Martin

Erik Postma @erikpostma.bsky.social · Aug 22

With #eseb2025 coming to a close, it is time to start making plans for 2026. Interested in the interface of evolution 🧬 and ecology 🌳? Come to our #ExE conference hosted by @uniexecec.bsky.social in beautiful #Cornwall. Leave your email address at tinyurl.com/EvolxEcol to join our mailing list!

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Jordan S. Martin @jsmartin.bsky.social · Aug 20

A landmark paper for the evolutionary biology of behavior. Fascinating work on how manipulating cell type-specific gene expression can rewire the brain to produce a key mating behavior observed in a sister species that diverged ~35 mya.

www.science.org/doi/10.1126/...

Cross-species implementation of an innate courtship behavior by manipulation of the sex-determinant gene

In accepting a courting male, Drosophila subobscura females require nuptial gift giving in which a male gives regurgitated crop contents to her mouth to mouth. No similar behavior is found in D. melan...

www.science.org

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Jordan S. Martin @jsmartin.bsky.social · Aug 11

For those interested in learning more about phenotypic versions of the CRN, especially for life history traits, check out some awesome recent work and applications in collaboration with @lbliard.bsky.social

besjournals.onlinelibrary.wiley.com/doi/full/10....

ecoevorxiv.org/repository/v...

Detecting context dependence in the expression of life history trade‐offs

This proof-of-concept paper highlights that the context dependence of trade-offs can be successfully detected, hence potentially improving our understanding of life-history theory. Photo credit: Arpa...

besjournals.onlinelibrary.wiley.com

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Jordan S. Martin @jsmartin.bsky.social · Aug 11

Ultimately, I hope the method will aid in better understanding how quantitative G x E is shaping multivariate trait evolution in response to dynamic social and ecological change (socio-eco-evo) on contemporary timescales.

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Jordan S. Martin @jsmartin.bsky.social · Aug 11

I also demonstrate the utility of the CRN using an exceptional long-term dataset on meerkat behavior from work by @tomhouslay.bsky.social et al. (big thanks to Tom!) The CRN shows how specialization among cooperative tasks changes plastically in response to sex, age, dominance, and group size.

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Jordan S. Martin @jsmartin.bsky.social · Aug 11

I use simulations to show that the CRN is not only a valid model for inferring complex environmental effects, but also that it can outperform standard methods at modest sample size in more idealized scenarios with a single environmental effect (climate warming).

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Jordan S. Martin @jsmartin.bsky.social · Aug 11

There are great methods for estimating environmental effects on trait (co)variances, but their utility is limited for investigations of complex environmental effects in the field, esp. when repeated measurements and/or experimental breeding designs are unfeasible. The CRN answers this challenge.

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Jordan S. Martin @jsmartin.bsky.social · Aug 11

While G and P can be highly stable under certain conditions, there are many cases where trait (co)variances are expected to rapidly respond to continuous environmental change across space and time. Explaining the dynamics of trait development and evolution requires understanding these relationships.

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Jordan S. Martin @jsmartin.bsky.social · Aug 11

My first solo author paper is now available in early view at Methods in Ecology and Evolution! I develop a covariance reaction norm (CRN) model for estimating continuous, multivariate, and nonlinear environmental effects on G and P matrices.

besjournals.onlinelibrary.wiley.com/doi/10.1111/...

Covariance reaction norms: A flexible method for estimating complex environmental effects on trait (co)variances

Estimating quantitative genetic and phenotypic (co)variances is crucial for investigating evolutionary ecological phenomena such as developmental integration, life history trade-offs and niche spe...

besjournals.onlinelibrary.wiley.com

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Reposted by Jordan S. Martin

Jordan S. Martin @jsmartin.bsky.social · Aug 7

Hot on the tail of our Tsimane IGE study comes the theory paper that motivated it! What are the ecological causes and evolutionary consequences of social plasticity in dynamic environments? See our new Functional Ecology paper to find out more

besjournals.onlinelibrary.wiley.com/doi/10.1111/...

Frequency dependence favours social plasticity and facilitates socio‐eco‐evolutionary feedback in fluctuating environments

Read the free Plain Language Summary for this article on the Journal blog.

besjournals.onlinelibrary.wiley.com

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Jordan S. Martin @jsmartin.bsky.social · Aug 7

Big thanks to my excellent collaborators and coauthors on the project @ali--wilson.bsky.social, @dingemanselab.bsky.social, David Westneat, and Yimen Araya-Ajoy

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Jordan S. Martin @jsmartin.bsky.social · Aug 7

Hot on the tail of our Tsimane IGE study comes the theory paper that motivated it! What are the ecological causes and evolutionary consequences of social plasticity in dynamic environments? See our new Functional Ecology paper to find out more

besjournals.onlinelibrary.wiley.com/doi/10.1111/...

Frequency dependence favours social plasticity and facilitates socio‐eco‐evolutionary feedback in fluctuating environments

Read the free Plain Language Summary for this article on the Journal blog.

besjournals.onlinelibrary.wiley.com

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Reposted by Jordan S. Martin

Jordan S. Martin @jsmartin.bsky.social · Jul 30

I'm very excited to share the central paper from my PhD out now in Science Advances. We investigated how social effects among neighbors shape the evolution of reproductive cooperation and the pace of adaptive population growth among the Indigenous Tsimane of Bolivia.
www.science.org/doi/10.1126/...

Indirect genetic effects among neighbors promote cooperation and accelerate adaptation in a small-scale human society

Social effects on fertility promote population growth and the evolution of flexible cooperation in a small-scale human society.

www.science.org

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Jordan S. Martin @jsmartin.bsky.social · Jul 30

Thanks, Tanay! 😃

Jordan S. Martin @jsmartin.bsky.social · Jul 30

Deep thanks and appreciation are owed to my coauthors, particularly those on Bsky @babeheim.bsky.social and @mgurven.bsky.social, as well as my PhD advisor @jaeggiadrian.bsky.social for their excellent collaboration and support.

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Jordan S. Martin @jsmartin.bsky.social · Jul 30

These findings provide critical support for the social drive hypothesis, suggesting that IGEs can precipitate socio-eco-evolutionary feedback that drives rapid population growth and social evolution in human societies. Please see the paper for further details and discussion!

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Jordan S. Martin @jsmartin.bsky.social · Jul 30

We also show that the local consequences of IGEs fluctuate across neighborhoods and communities in response to socioecological factors. This suggests that plasticity in reproductive cooperation is also being maintained by spatiotemporal variation in neighbors' effects on one another's fertility.

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Jordan S. Martin @jsmartin.bsky.social · Jul 30

Results demonstrate that social effects on fertility promote the evolution of reproductive cooperation, while also playing an outsized role in determining the evolvability of individual fitness. In comparison to direct effects alone, IGEs are predicted to increase the pace of adaptation by 5x.

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Jordan S. Martin @jsmartin.bsky.social · Jul 30

To test key predictions from the model, we combined cutting-edge Bayesian methods with the largest demographic dataset available on a contemporary foraging-oriented society, to analyze genetic effects on fertility variation among Tsimane women and their neighbors over a 20y period.

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Jordan S. Martin @jsmartin.bsky.social · Jul 30

We combine evolutionary anthropological and quantitative genetic theory to propose a novel social drive hypothesis, which predicts that indirect (i.e. social) genetic effects (IGEs) on fitness play a key role in explaining our species' rapid social evolution and biodemographic success.

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Jordan S. Martin @jsmartin.bsky.social · Jul 30

I'm very excited to share the central paper from my PhD out now in Science Advances. We investigated how social effects among neighbors shape the evolution of reproductive cooperation and the pace of adaptive population growth among the Indigenous Tsimane of Bolivia.
www.science.org/doi/10.1126/...

Indirect genetic effects among neighbors promote cooperation and accelerate adaptation in a small-scale human society

Social effects on fertility promote population growth and the evolution of flexible cooperation in a small-scale human society.

www.science.org

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Reposted by Jordan S. Martin

Journal of Evolutionary Biology @jevbio.bsky.social · Jul 2

@barbaraclass.bsky.social et al. assess how well different statistical models estimate indirect genetic effects and assortative mating when partner similarity is caused by multiple co-occurring processes
@jsmartin.bsky.social @mmoiron.bsky.social

academic.oup.com/jeb/advance-...

Disentangling nonrandom assortment, indirect effects, and joint plasticity as causes of phenotypic (dis)similarity between social partners

Abstract. Social partners frequently resemble each other. These correlations between the phenotypes of interacting individuals (e.g., social partners, grou

academic.oup.com

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Jordan S. Martin @jsmartin.bsky.social · Dec 16

Nothing quite lifts your spirits like having R2 thank you for giving them the chance to read "an insightful piece of work" that they "really liked". Thanks to you, anonymous colleague, for a little sunshine on this overcast day 🌻

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Reposted by Jordan S. Martin

Alfredo Sánchez-Tójar @asanchez-tojar.bsky.social · Dec 9

Four years ago we showed that only 27% of articles published in ecological journals WITH a code-sharing policy made their code available, leading to a 21% reproducibility potential.

📰 doi.org/10.1371/jour...

We've looked into journals WITHOUT a code-sharing policy.

Results coming soon...

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Jordan S. Martin @jsmartin.bsky.social · Dec 9

One of the most fascinating papers of the year...

"...infanticide occurred in multiple contexts due to multiple drivers. Nevertheless, 48% of stepparents of both sexes adopted offspring, and another 23% of stepfathers exhibited both infanticide and long-term care."

www.pnas.org/doi/10.1073/...

Eviction-driven infanticide and sexually selected adoption and infanticide in a neotropical parrot | PNAS

Infanticide and adoption have been attributed to sexual selection, where an individual later reproduces with the parent whose offspring it killed o...

www.pnas.org

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