jeffgroh.bsky.social
Jeff Groh
@jeffgroh.bsky.social
230 followers 150 following 19 posts
Postdoc at UC Berkeley | evolutionary genetics & genomics, plant mating systems, hybridization
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jeffgroh.bsky.social
Jeff Groh @jeffgroh.bsky.social · Jan 3
It feels surreal to see my PhD research featured on the cover of Science www.science.org/doi/10.1126/.... Incredibly proud of the work that went into this. And so grateful for the opportunities, resources, support and mentorship from co-authors and my whole scientific community that made it possible
Pollination in walnuts (such as this Persian walnut, Juglans regia) and pecans occurs through a genetically controlled temporal flowering dimorphism. Two distinct morphs alternate their phases of male and female flowering across the season, promoting outcrossing that has maintained a stable equilibrium throughout tens of millions of years of evolution. See eado5578. Photo: Philippe Clement/NPL/Minden Pictures
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Reposted by Jeff Groh
biorxiv-evobio.bsky.social
bioRxiv Evolutionary Biology @biorxiv-evobio.bsky.social · 18d
Quantitative system drift https://www.biorxiv.org/content/10.1101/2025.09.17.676933v1
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stepheniwright.bsky.social
Stephen I Wright @stepheniwright.bsky.social · Aug 27
Please share broadly: I am looking for a postdoctoral fellow to work on a collaborative project on the temporal population genomics of invasive Capeweed (using contemporary and herbarium genomics), with ‪‪@shaky-dingo.bsky.social‬ and colleagues
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kitchensjn.bsky.social
James Kitchens @kitchensjn.bsky.social · Aug 19
Excited to share our new preprint for the tskit_arg_visualizer Python package! ARGs can sometimes feel like a black box, so
@yanwong.bsky.social and I have been developing a method to programmatically drawing these graphs.

🔗 arxiv.org/abs/2508.03958

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tskit_arg_visualizer: interactive plotting of ancestral recombination graphs
Summary: Ancestral recombination graphs (ARGs) are a complete representation of the genetic relationships between recombining lineages and are of central importance in population genetics. Recent brea...
arxiv.org
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Reposted by Jeff Groh
sciforgood.bsky.social
Science for Good ☀️ @sciforgood.bsky.social · Jun 26
Fields like Computer Science, Physics/Astronomy, and Chemistry saw the largest increases in NSF GRFP awards in 2025.

Meanwhile, Life Sciences, Social Sciences, Psychology, and Mathematical Sciences experienced the steepest declines—marking a major departure from historical funding patterns.
Shift in NSF GRFP award by field. The color shows the field, and the proportion of grants awarded is shown by the slope and weight of the line.
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jeffgroh.bsky.social
Jeff Groh @jeffgroh.bsky.social · Jun 20
Looking forward to #Evol2025! I’ll be presenting on the genetics of a balanced polymorphism for sex timing in hermaphroditic plants in the Reproductive Systems session on June 22 at 11:15 AM
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Reposted by Jeff Groh
joshuasweitz.bsky.social
Joshua Weitz @joshuasweitz.bsky.social · May 31
How bad will it be? Catastrophic.

Proposed cuts to #NSF, #NIH, and #NASA will set the US R&D landscape back 25 yrs+, cause economic and job loss now, and undermine innovations to come.

But, this is the WH's *proposed* budget.

Speak up now before it is too late.

(inflation adjusted $-s below)
NSF, NASA and NIH budgets per year, inflation adjusted from 2000-2025 along with the proposed cuts. NSF includes research component only. Massive cuts across all sectors, well below support spanning 25 years.
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jeffgroh.bsky.social
Jeff Groh @jeffgroh.bsky.social · May 15
Congrats!!
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ben-moran.bsky.social
Ben Moran @ben-moran.bsky.social · May 1
1/9 Excited to share the preprint for the second half of my PhD with @mollyschumer.bsky.social: Connecting human environmental impacts to hybridization in swordtail fish through genomics, GIS, water chemistry, and histology. Thread below!

#SciSky

www.biorxiv.org/content/10.1...
Increased rates of hybridization in swordtail fish are associated with water pollution
Biodiversity loss can occur when disturbance compromises the reproductive barriers between species, causing them to collapse into a single population through hybridization. Recent research has documen...
www.biorxiv.org
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jeffgroh.bsky.social
Jeff Groh @jeffgroh.bsky.social · Apr 24
Congrats to my wonderful PhD advisor @gcbias.bsky.social on being elected to American Academy of Arts & Sciences! www.amacad.org/new-members-...
New Academy Members
Elected in 2025
www.amacad.org
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sciencehomecoming.bsky.social
Science Homecoming @sciencehomecoming.bsky.social · Apr 10
Biologist Jeff Groh wrote home to Hummelstown PA 🚜 to lay out the many costs of cuts to American science infrastructure. “Let’s not ruin a good thing” 🧪🏠
jeffgroh.bsky.social
Jeff Groh @jeffgroh.bsky.social · Apr 10
Inspired by others on here I wrote a short op-ed in support of federal research funding for a local newspaper in small town PA where I grew up
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jeffgroh.bsky.social
Jeff Groh @jeffgroh.bsky.social · Apr 10
Inspired by others on here I wrote a short op-ed in support of federal research funding for a local newspaper in small town PA where I grew up
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Reposted by Jeff Groh
theatlantic.com
The Atlantic @theatlantic.com · Apr 6
More than 1,200 demonstrations were held across the country on Saturday against the policies and actions of President Donald Trump and Elon Musk. See images from some of the protests in California, Florida, Washington, D.C., and more.
Photos: Nationwide Protests Against Trump and Musk
Images from some of the hundreds of anti-Trump demonstrations across the country.
bit.ly
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jeffgroh.bsky.social
Jeff Groh @jeffgroh.bsky.social · Mar 12
Thanks! It certainly seems that a common theme is structural DNA variation affecting allele-specific regulation of flowering genes to regulate timing. In this case, we don't find evidence that the mechanism directly involves the 3' UTR
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micamer.bsky.social
micamer.bsky.social @micamer.bsky.social · Mar 11
We would love feedback on a new NCBI-BLAST service we are launching today: sky-blast.com

Under the hood it's the same BLAST executable and databases provided by NCBI, with a replica of the NIH's interface - providing an alternative to the US gov service that's less congested, faster & more reliable
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jeffgroh.bsky.social
Jeff Groh @jeffgroh.bsky.social · Mar 12
updated link to their preprint www.biorxiv.org/content/10.1...
www.biorxiv.org
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jeffgroh.bsky.social
Jeff Groh @jeffgroh.bsky.social · Mar 11
Grateful for the support from co-authors including Gracie Ackerman (UCD undergrad), PhD advisor @gcbias.bsky.social , M Wenzel of Sonoma Bot Garden, and USDA Wolfskill germplasm collection
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jeffgroh.bsky.social
Jeff Groh @jeffgroh.bsky.social · Mar 11
We discuss the implications of our findings for evolution of heterodichogamy, and turnover vs stability of the genetic systems that control it.
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jeffgroh.bsky.social
Jeff Groh @jeffgroh.bsky.social · Mar 11
Heterodichogamy in Cyclocarya involves a distinct pair of alleles at GFAFL with a reversed direction of dominance. The alleles are specialized in unisexual flowers and expr again implies a trans interaction. Parallel genomic structure to the Pterocarya locus suggests a similar mechanism in both
Similar haplotype structure for heterodichogamy in both Pterocarya and Cyclocarya, and gene expression patterns of GFAFL in Cyclocarya flowers
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jeffgroh.bsky.social
Jeff Groh @jeffgroh.bsky.social · Mar 11
In work done independently from ours, a separate group identifies the same locus and expression patterns with complementary methods, and provides direct evidence for regulation by small RNAs. doi.org/10.1101/2025...
doi.org
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jeffgroh.bsky.social
Jeff Groh @jeffgroh.bsky.social · Mar 11
In Pterocarya the trait maps to a narrow region of balanced polymorphism containing a single flowering gene, GFAFL. Allele-specific GFAFL expression patterns in flowers imply existence of a trans-acting mechanism which we hypothesize to involve small RNA based on structure of the dominant haplotype
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jeffgroh.bsky.social
Jeff Groh @jeffgroh.bsky.social · Mar 11
I'm excited to share our new preprint on the molecular evolution of heterodichogamy in two wingnut genera of Juglandaceae. Heterodichogamy features two morphs synchronously alternating male and female flowering phases in time to generate disassortative mating.
doi.org/10.1101/2025...
Pictures of two dichogamy morphs in Pterocarya trees, a graph visualizing flower dimorphism, and a phylogeny of the Juglandaceae family showing divergence times and origins of genetic systems for heterodichogamy.
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biorxiv-evobio.bsky.social
bioRxiv Evolutionary Biology @biorxiv-evobio.bsky.social · Mar 11
Allelic turnover and dominance reversal at a single-gene balanced polymorphism controlling heterodichogamous flowering in wingnuts (Juglandaceae) https://www.biorxiv.org/content/10.1101/2025.03.10.642504v1
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standupforscience.bsky.social
Stand Up for Science! @standupforscience.bsky.social · Mar 6
WHERE WILL YOU BE TOMORROW?
Stand up for science flyer, happening on March 7th in DC & nationwide with more information at www.standupforscience2025.org
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Reposted by Jeff Groh
mikemihalitsis.bsky.social
Michalis Mihalitsis @mikemihalitsis.bsky.social · Mar 4
1/10 *** New paper out *** (on behalf of Nick Peoples who is not on Bluesky). I am beyond excited to present our new paper out now in @Nature! Here, we show that rapid gain and loss of tooth complexity accelerates diversification in fishes! www.nature.com/articles/s41...
Evolutionary lability of a key innovation spurs rapid diversification - Nature
A study shows that the rapid diversification of cichlids in African lakes is driven by their ability to evolve between having simple or complex teeth.
www.nature.com
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jeffgroh.bsky.social
Jeff Groh @jeffgroh.bsky.social · Mar 2
This one hits close to home. Rachel was one of the collections managers for a nat'l germplasm repository in Winters, CA where I've done a lot of my research. Invaluable resource that that will take a big hit from this www.nytimes.com/2025/03/02/u...
Horticulturalists, Biologists, Engineers: Federal ‘Bloat’ or Valued Experts?
President Trump’s effort to remake the government is a direct challenge to a decades-long effort to build a civil service stocked with experts. Critics say it will backfire.
www.nytimes.com
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