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Matt Rockman @wormsrock.bsky.social · 10d

Thanks!

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Reposted by Matt Rockman

Erick Arrashy Rudianto @erickrudianto.bsky.social · 11d

This is my first time seeing alive lernanthropid copepod (possibly Lernanthropus latis)!

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Reposted by Matt Rockman

Laurent Formery @laurentformery.bsky.social · 12d

Sea urchin metamorphosis is maybe one of the most radical event in developmental biology. In just about an hour, these little pluteus larvae completely reorganize their entire body plan.

Very happy that this video got awarded an honorable mention by #NikonSmallWorld 😃

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Reposted by Matt Rockman

Jenn Coughlan @jenncoughlan.bsky.social · 12d

We're on a roll: Super proud of this paper lead by Dr. Megan Frayer & GS Hagar Soliman (with a major contrib from GS Pia Schwarz): Introgression and Parental Conflict Shape Repeated Occurrences of Postzygotic Isolation @hybridzones.bsky.social @hagarsoliman.bsky.social @pfschwarz.bsky.social

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Matt Rockman @wormsrock.bsky.social · 13d

Yeah, it's weird! Tim Crombie and @erikandersen.bsky.social & co. have characterized global C. elegans population genetics and the pattern is pretty clear. A key paper:

Deep sampling of Hawaiian Caenorhabditis elegans reveals high genetic diversity and admixture with global populations

Hawaiian Caenorhabditis elegans harbor high levels of genetic diversity that might represent the complex patterns of ancestral diversity in the species prior to human influence.

elifesciences.org

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Matt Rockman @wormsrock.bsky.social · 13d

Thanks! Africa is definitely undersampled. Modest efforts in Ethiopia, Kenya, South Africa, Cabo Verde, and a few other places have turned up the cosmopolitan species, but there are no doubt tons more endemics like C. afra in the rainforests.

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Matt Rockman @wormsrock.bsky.social · 13d

Thanks!

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Matt Rockman @wormsrock.bsky.social · 13d

Thanks!

Matt Rockman @wormsrock.bsky.social · 14d

Finally, Pohnpei is one of the most fascinating and delightful places imaginable - spectacular scenery, unique biology, and most of all, exceptionally generous people and culture. It was an incredible privilege to visit and work there.

A view of Sokehs Ridge from the northwest edge of Kolonia. A thatched-roof shelter is at right. From the foreground the land drops down, over some banana plants, toward the lagoon. Sokehs Rock, a basalt monolith 200m high, looms in the distance. The picture doesn't show the endemic serehd lorikeets or pwehk flying foxes, but they're in there.

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Matt Rockman @wormsrock.bsky.social · 14d

That is, Oceania looks like a source for Asian species, not the reverse! Here’s the preprint.

Caenorhabditis diversity on Pohnpei, Micronesia, provides evidence that the Elegans Supergroup has its roots in the Americas and diversified in the Pacific en route to Asia

The microscopic nematode Caenorhabditis elegans stands unrivaled as a model for developmental biology, neurobiology, and genetics, but fundamental aspects of its ecology, biogeography, and natural his...

www.biorxiv.org

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Matt Rockman @wormsrock.bsky.social · 14d

Surprisingly, the phylogeny implies (equivocally, to be sure) that the Elegans Supergroup of species, which includes C. elegans, is derived from American ancestors, and that a lot of the groups diversification may have taken place in Oceania, prior to subsequent invasions of Asia.

Biogeographic ancestral area reconstruction, with pie-charts at the nodes of a phylogeny indicating estimated marginal probabilities for each region. This phylogeny excludes a bunch of species whose distributions reflect human activity and whose pre-anthropogenic-movement distributions are unknown. The main result is that there's a lot of red (Oceania) in the deeper nodes of the Elegans Supergroup. There's other colors too, to be sure.

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Matt Rockman @wormsrock.bsky.social · 14d

The goal was to understand biogeography, so we sequenced transcriptomes for the new species, and several others, and built the largest-yet Caenorhabditis phylogeny. The most common Pohnpeian species (C. pwilidak sp nov) is sister to a Hawaiian endemic clade!

A phylogeny of 70 Caenorhabditis species, based on protein sequences for 2955 genes. Adjacent to each species name is a set of colored circles indicating which continents each species is known from, with Remote Oceania included as its own region. Names of the nine species found in Pohnpei are bolded.

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Matt Rockman @wormsrock.bsky.social · 14d

We didn’t find C. elegans. But we did find 9 Caenorhabditis species, five of them new, some with distinct habitat profiles. We gave them formal names based on Pohnpeian words. A Pohnpeian language summary of the research is at this link:

Learning from the worms of Pohnpei, FSM

rockmanlab.bio.nyu.edu

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Matt Rockman @wormsrock.bsky.social · 14d

In Pohnpei, we processed more than 500 samples through Baermann funnels and established more than 1000 isofemale cultures of Caenorhabditis. Our data let us estimate basic parameters of Caenorhabditis population biology (e.g., ~5 worms found each new patch).

Figure 4 from the preprint. At left, pictures of six different kinds of rotting thing that we extracted worms from, with their Pohnpeian and scientific names. At right, two graphs related to estimates of the number of worms that colonize each rotting thing.

Back in the lab in New York, about 1000 3.5cm petri dishes, each containing an isofemale or isohermaphrodite culture of Caenorhabditis from Pohnpei. Next steps were to ID each to species, and cryopreserve. This picture is here to remind everybody that this was not a vacation! Hard work!

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Matt Rockman @wormsrock.bsky.social · 14d

This was a great collaboration between my lab - me, Sophie Tintori, and Tuc Nguyen - and Harmony Yomai, a Micronesian plant ecologist. We also had help from fantastic local experts who led us to sites all over the island, including the spectacular cloudforests in the island’s interior.

Cloudforest on top of Kupwuriso; tall kotop palms (Clinostigma ponapensis) covered in epiphytes.

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Matt Rockman @wormsrock.bsky.social · 14d

We went to the only place with high elevation forest between Hawaii and Asia: the island of Pohnpei in the Federated States of Micronesia. An extinct volcano older than the main Hawaiian Islands, Pohnpei is covered in intact ancient rainforest and cloudforest.

A view toward the ocean across forested mountain scenery, with palms in the foreground. This is on the slopes of Kupwuriso.

A map of the southwest Pacific Ocean, with an arrow pointing to Pohnpei (capital city Kolonia). It's about 1500 km northeast of New Guinea and 1500 km southeast of Guam and 5000 km southwest of Hawaii and perfect in every way.

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Matt Rockman @wormsrock.bsky.social · 14d

C. elegans is a real animal and we set out to understand how it comes to have its distinctive biogeography. Its ancestral center of diversity is in the higher elevation forests of Hawaii. Its closest relatives are spread across east Asia. Did they travel from Asia? [Preprint 🧵]

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Matt Rockman @wormsrock.bsky.social · 16d

Preprint teaser!
Keep an eye out for our forthcoming paper on the Caenorhabditis nematodes of Pohnpei, Micronesia, and their implications for biogeography and ecology.

A view of Nan Madol, the temple precinct and seat of government of Pohnpei under the Saudeleur dynasty. The city was built about 700 years ago from massive columns of basalt. The image shows one corner of the Nandauwas, with 25-foot high walls built Lincoln-log-style from the basalt columns. In the foreground is one of the canals that form the streets of Nan Madol.

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Matt Rockman @wormsrock.bsky.social · 18d

I’m not sure tourists are allowed— stolen valor and all that

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Matt Rockman @wormsrock.bsky.social · 19d

Ithaca is gorges

Gorges. Here’s Lucifer Falls in Treman State Park. Water flows over layers of shale, tree-topped cliffs on each side.

Sun glinting off water, backlit foliage, Treman State Park

Water flowing through a strikingly linear channel in perfectly horizontal strata of Devonian shale, Buttermilk State Park.

Curvy pedestal of rock left by years of erosion in Buttermilk Gorge

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Reposted by Matt Rockman

Christian Braendle @braendle.bsky.social · 23d

The Braendle Lab in Nice, France is hiring two postdocs to study nematode genetics, evolution, and ecology. Start Jan–Jul 2026. Deadline Nov 30, 2025. Apply: [email protected]

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Matt Rockman @wormsrock.bsky.social · Sep 8

Her name is MOTHER OF EXILES. From her beacon-hand glows world-wide welcome.

Pictures from a visit yesterday

A view of the statue's torch-bearing arm, from the windows in the crown. The arm and its clothes are green. Behind it, New York Harbor with some boats. The Verrazano Bridge is in the distance.

A view from inside the statue of a metal ladder that leads up to the statue's torch. Off limits!

The plaque bearing Emma Lazarus' poem, The New Colossus. The National Park Service is super clear that this is a central part of the meaning of the statue. Here's the poem text:

Not like the brazen giant of Greek fame,
With conquering limbs astride from land to land;
Here at our sea-washed, sunset gates shall stand
A mighty woman with a torch, whose flame
Is the imprisoned lightning, and her name
Mother of Exiles. From her beacon-hand
Glows world-wide welcome; her mild eyes command
The air-bridged harbor that twin cities frame.
“Keep, ancient lands, your storied pomp!” cries she
With silent lips. “Give me your tired, your poor,
Your huddled masses yearning to breathe free,
The wretched refuse of your teeming shore.
Send these, the homeless, tempest-tost to me,
I lift my lamp beside the golden door!”

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Reposted by Matt Rockman

Anne C. Hart @ach-ceneuro.bsky.social · Sep 4

New #postdoc position focused on ALS/FTD available in the Hart lab! Join the collaborative Brown Univ. #neuroscience community! Experience with invertebrate genetics (like #Celegans) and/or neurodegenerative disease is welcome, but not required. Details at apply.interfolio.com/172914

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Reposted by Matt Rockman

Samuel Church @shchurch.bsky.social · Aug 28

The Church Evolution Laboratory (CEL@NYU) will be official as of Sep 1st: shchurch.github.io. We are recruiting at all levels, including a postdoc to work on evolutionary patterns and processes via comparative genomics in Hawaiian Drosophila. Please share widely!

Church Evolution Laboratory

Department of Biology, New York City

shchurch.github.io

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Reposted by Matt Rockman

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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