Santiago Claramunt

Fossilized skeletons of several extinct birds, some including preserved remains of plumage.

Phylogeny of Eocene parrot- and passerine-like birds: vertebrate-zoology.arphahub.com/article/1825... 🪶🧪 (📷Mayr)

A covarion model for phylogenetic estimation using discrete morphological datasets Abstract. The rate of evolution of a single morphological character is not homogeneous across the phylogeny and this rate heterogeneity varies between morp

Our new paper 'A covarion model for phylogenetic estimation using discrete morphological datasets,' is out in SysBio!
We introduce the "covariomorph" model in RevBayes to capture character and lineage specific rates of morphological traits.
🔗 doi.org/10.1093/sysb...

Come join me and other great colleagues at @ib_unam !! We’re searching for a new orno 🦅 🦢 🦉 systematics researcher/prof. for the largest bird collection in Mexico. See details herein www.ib.unam.mx/ibunam/Convo... Amigxs ornitólogxs! Habemus búsqueda de nuevx investigadorx! Apliquen!

Fig. 1 from the article: Illustration of the two main wing muscles – pectoralis and supracoracoideus – of a migratory passerine.

Fig. 4 from the article: Representation of the diverse ways in which myokines can influence the function of different organs throughout the body.

Fig. 5 from the article: (A) Conceptualization of a behavioral control system, as outlined by Fuxjager et al. (2023). Behavioral control systems are shown through the lens of spring (B) and autumn (C) migrations, with skeletal muscle (dark red) playing a role in the regulation of physiological systems that all promote one singular behavioral node (migration, dark orange) at the expense of others (dimmed behavioral nodes).

New paper: a review of how skeletal muscles support long-distance bird migration, highlighting their plasticity, coordination via endocrine signals, and interactions with other organ systems.

➡️ vist.ly/4sdqf

#ornithology #birds #migration #physiology #signals #adaptation #evolution

Reminder: 2026 Latin American/Caribbean Conservation Research Grant applications are due by 2/27 at 11:59pm ET. If you need guidance on completing your application, please see the slide presentations available on our website.
americanornithology.org/awards-grant...

A mosaic of modular variation at a single gene underpins convergent plumage coloration The reshuffling of genomic variation from multiple origins is an important contributor to phenotypic diversification, yet insights into the evolutionary trajectories of this combinatorial process and ...

1/9 New in @science.org www.science.org/doi/10.1126/science.ado8005
How does genetic architecture constrain evolutionary trajectories? To address this question, we inferred the genetic architecture of convergent plumage coloration and its evolutionary history in wheatears.

Audubon at Carnival: Party Like It’s 1873 Birds took over New Orleans in the middle of the state’s worst political crisis

I did a full write-up here. Laissez les bons temps rouler
birdhistory.substack.com/p/audubon-at...

Ornithology X Mardi Gras X Art history thread — highly recommended

Fossilized partial skeleton of an extinct bird closely related to modern ibises. The specimen has been split into two separate slabs, both of which are pictured.

New sharp-billed stem-ibis Rhynchaeites mcfaddeni: www.cambridge.org/core/journal... 🪶🧪 (📷 @ksepkalab.bsky.social et al.)

Interesting. Migratory Yellow Warblers don't have longer wings. They attain higher aspect ratio by shortened secondaries. An increase in efficiency that seems to favour speed over easiness.

Dive Deep into Probabilistic Phylogenetic Comparative Methods Transmitting Science ONLINE course Dive Deep into Probabilistic Phylogenetic Comparative Methods, by Dr. Ignacio Quintero.

Want to learn the ins and outs of diversification, trait and biogeographic evolution models? I will be giving another edition of "Dive Deep into Probabilistic Phylogenetic Comparative Methods" in Oct! @tscourses.bsky.social www.transmittingscience.com/courses/evol...

🧉⏱️🧬

📣 Grad student wanted
PhD position in avian evolution, with emphasis on phylogenetics, macroevolution, Neotropical radiations, flight and dispersal.
Based at the University of New Orleans (soon to be LSU New Orleans).
Start: September 2026.
Contact me if interested.
claramuntlab.org

Brown Cacholote - Pseudoseisura lophotes - Birds of the World Species accounts for all the birds of the world.

Usually described as “raucous” and “cacophonous,” the Brown Cacholote is an energetic South American ovenbird. The bird announces its presence by performing its long, loud series of grating notes from treetops. Listen to some duets here: birdsoftheworld.org/bow/species/brncac1

Fossilized wing bones of honeyguide birds.

Honeyguides from the Varswater Formation (Pliocene of South Africa), the oldest known fossil honeyguides: riviste.unimi.it/index.php/RI... 🪶🧪 (📷Louchart et al.)

Mandibular morphology clarifies phylogenetic relationships near the origin of crown birds - BMC Ecology and Evolution Background The phylogenetic relationships of fossil birds near the origin of the avian crown group remain debated, in part due to a limited amount of character evidence from incomplete fossils. The av...

🚨NEW PAPER OUT🚨
The anatomy of bird lower jaw bones has been understudied...until now! Here, we examine avian mandibular anatomy, answering some and raising more questions about the phylogenetic affinities of key early crown-group birds. Read on!
link.springer.com/article/10.1...

Myiarchus flycatchers ordered by size and intensity of yellow underparts. When it comes to flycatchers, differences between species tend to be very subtle. Impressions of size and color in the field can be quite subjective, but the differences are real.

Flat illustration of a Willow Ptarmigan perched in wintry trees with 3 camouflaged in the snowy background. (From 2025)

Snowy Ptarmigans!

ML616675248 - American Woodcock - Macaulay Library Macaulay Library ML616675248; © Karim Bouzidi; Longueuil, Quebec, Canada

Remarkable photo illustrating (American) Woodcock visual field

macaulaylibrary.org/asset/616675...

'Sandpipers' by Julia Berman.

How did birds evolve? The answer is wilder than anyone thought Discoveries in Jurassic rocks reveal that birds were adept fliers earlier than scientists realized.

How did birds evolve? The answer is wilder than anyone thought www.nature.com/articles/d41...

Where Can You Find A One-Of-A-Kind Pocket Shark Among 8 Million Pickled Fish? Louisiana's WWII Bunkers, Of Course The largest collection of its kind includes a specimen you won't find anywhere else on Earth.

OMG I'm in IFLScience!

Oxygen-free metabolism in the bird inner retina supported by the pecten - Nature While the photoreceptor outer segments in the bird outer retina have access to oxygen, the inner retina operates under chronic anoxia, supported by anaerobic glycolysis in the retinal neurons.

Birds have a thick retina devoid of blood vessels - so how do they ensure sufficient oxygen availability?
They don't - neurons rely on glycolysis, metabolizing glucose released from the pecten.

Insane new study that includes comparative data on lizards and crocs.🧪

www.nature.com/articles/s41...

What's larger, a protein or its templating mRNA ?

> The mRNA is much larger.

⬛ 𝐀 𝐬𝐞𝐧𝐬𝐞 𝐨𝐟 𝐬𝐜𝐚𝐥𝐞 -- 𝐪𝐮𝐚𝐧𝐭𝐢𝐭𝐚𝐭𝐢𝐯𝐞 𝐢𝐧𝐭𝐮𝐢𝐭𝐢𝐨𝐧 & 𝐜𝐨𝐧𝐬𝐭𝐫𝐚𝐢𝐧𝐭𝐬 -- 𝐢𝐬 𝐚 𝐩𝐨𝐰𝐞𝐫𝐟𝐮𝐥 𝐞𝐧𝐚𝐛𝐥𝐞𝐫 𝐨𝐟 𝐫𝐞𝐬𝐞𝐚𝐫𝐜𝐡.

The figure shows myoglobin protein drawn to scale next to its mRNA template. The coding sequence of an mRNA ...

Fossilized skeleton of a small extinct bird.

New halcyornithid (early close relative of parrots and passerines) Scopsoides feisti: www.schweizerbart.de/papers/njgpa... (From late last year, but I didn't get a copy of the paper until recently.) 🪶🧪 (📷Mayr)

Fossilized skeletons of a small extinct bird.

New specimens of the nightjar-like Hassiavis: www.tandfonline.com/doi/full/10.... Some of the new anatomical information here suggests that it might have been more closely related to owlet-nightjars, swifts, and hummingbirds than to true nightjars. 🪶🧪 (📷Mayr & Richter)

The great @jembrown.bsky.social closing out #ssb2026

It was a wonderful meeting thanks to the hardwork of Jeremy and funding from @lsu.bsky.social and other sources.

Systematic biology is alive and well. Especially proud of all the Global South who attended.

Strong @lsu.bsky.social contingent at #ssb2026 - LSU alumni and current folks

Society of Systematic Biologists A membership organization for anyone interested in the science of systematic biology.

“Scientific societies can support you and foster you through your whole career” - SSB President @trayc7.bsky.social opening the #ssb2026 meeting

Can’t join us today? Make sure your registration is up to date to keep up with SSB news and happenings

www.systbio.org

New paper out! 🐦📊

We realease AVONICHE, a global dataset with detailed information on the proportional use of 32 foraging niches, combining dietary categories with the behaviours and substrates used to access resources.

Openly access the paper and data in GEB: doi.org/10.1111/geb....