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joshuapaleorojas.bsky.social @joshuapaleorojas.bsky.social · 12h

Stephen Louis Brusatte, Juan Ignacio Canale, Leonardo Salgado, Diego Pol, and Michael Pittman, 2024. 🤓🦕🦖

joshuapaleorojas.bsky.social @joshuapaleorojas.bsky.social · 12h

posterior centrodiapophyseal lamina; prz, prezygapophysis; poz, postzygapophysis; dp, diapophysis; ns, neural spine; nc, neural channel; f, fossa. Scale bar: 1 centimeter. Photo credit: Jorge Gustavo Meso, Jonah Nathaniel Choiniere, Mattia Antonio Baiano,

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joshuapaleorojas.bsky.social @joshuapaleorojas.bsky.social · 12h

Michael Pittman, 2024. The sixth image shows the middle-posterior cervical vertebrae of MPCN-PV 738.27. A, cranial view; B, caudal view; C, dorsal view; D, left lateral view; E, right lateral view. Abbreviations: acdl, anterior centrodiapophyseal lamina; pcdl,

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joshuapaleorojas.bsky.social @joshuapaleorojas.bsky.social · 12h

prz, prezygapophysis; poz, postzygapophysis; tp, transverse process; vg, ventral groove; r, ridge. Scale bar: 1 centimeter. Photo credit: Jorge Gustavo Meso, Jonah Nathaniel Choiniere, Mattia Antonio Baiano, Stephen Louis Brusatte, Juan Ignacio Canale, Leonardo Salgado, Diego Pol, and

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joshuapaleorojas.bsky.social @joshuapaleorojas.bsky.social · 12h

and Michael Pittman, 2024. The fifth image shows the proximal caudal vertebrae of MPCN-PV 738.8. A, cranial view; B, left lateral view; C, caudal view; D, right lateral view; E, dorsal view; F, ventral view. Abbreviations: clas, caudal articular surface;

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joshuapaleorojas.bsky.social @joshuapaleorojas.bsky.social · 12h

view; G, MPCN-PV 738.2 in lateral view; H, medial view; I, dorsal view; J, cranial view; K, caudal view. Scale bar: 3 centimeters. Photo credit: Jorge Gustavo Meso, Jonah Nathaniel Choiniere, Mattia Antonio Baiano, Stephen Louis Brusatte, Juan Ignacio Canale, Leonardo Salgado, Diego Pol,

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joshuapaleorojas.bsky.social @joshuapaleorojas.bsky.social · 12h

Ignacio Canale, Leonardo Salgado, Diego Pol, and Michael Pittman, 2024. The fourth image shows the left scapulocoracoid of MPCN-PV 738. A, MPCA 1290. A, MPCN-PV 738.3 in lateral view; B, medial view; C, cranial view; D, caudal view; E, distal view; F, proximal

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joshuapaleorojas.bsky.social @joshuapaleorojas.bsky.social · 12h

view; E, proximal view; F, distal view. Abbreviations: g, groove; as, acetabular surface; pf, pubic foot; pa, pubic apron. Scale bar: 3 centimeters. Photo credit: Jorge Gustavo Meso, Jonah Nathaniel Choiniere, Mattia Antonio Baiano, Stephen Louis Brusatte, Juan

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joshuapaleorojas.bsky.social @joshuapaleorojas.bsky.social · 12h

credit: Jorge Gustavo Meso, Jonah Nathaniel Choiniere, Mattia Antonio Baiano, Stephen Louis Brusatte, Juan Ignacio Canale, Leonardo Salgado, Diego Pol, and Michael Pittman, 2024. The third image shows the left pubis of MPCN-PV 738.4. A, lateral view; B, caudal view; C, medial view; D, cranial

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joshuapaleorojas.bsky.social @joshuapaleorojas.bsky.social · 12h

lived in hybrid environments featuring tidal flats, estuaries, and coastal marine systems, which also supported aeolian (wind) systems and ephemeral lakes. The second image shows a skeletal reconstruction of alvarezsaurid MPCN-PV 738, referred to as Bonapartenykus ultimus. Photo

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joshuapaleorojas.bsky.social @joshuapaleorojas.bsky.social · 12h

found with the type specimen were unique and were given the new parataxonomic name Arriagadoolithus, leading to the creation of the Arriagadoolithidae family. Bonapartenykus likely ate insects and other small creatures, using its small, clawed forelimbs to dig into termite mounds. They

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joshuapaleorojas.bsky.social @joshuapaleorojas.bsky.social · 12h

is the largest alvarezsaur known so far, measuring 2.5 - 3.3 meters (8.2 - 10.8 feet) long and weighing 43 - 72 kilograms (95 - 159 lbs). B. ultimus lived during the Late Cretaceous Period, middle Campanian to lower Maastrichtian Ages, approximately 70 million years ago. Fascinatingly, the eggs

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joshuapaleorojas.bsky.social @joshuapaleorojas.bsky.social · 12h

youngest alvarezsaurids in South America. The name "onykus" (claw) refers to the prominent claw characteristic of the alvarezsaurid family. Classified as Animalia, Chordata, Reptilia, Dinosauria, Saurischia, Theropoda, Alvarezsauroidea, and Patagonykinae. Bonapartenykus

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joshuapaleorojas.bsky.social @joshuapaleorojas.bsky.social · 12h

same formation, specifically within the Salitral Ojo de Agua locality. Bonapartenykus ultimus means "Jose F. Bonaparte's claw" (from the genus name) and "latest" (from the specific name), honoring the Argentine paleontologist José F. Bonaparte and signifying it was one of the geologically

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joshuapaleorojas.bsky.social @joshuapaleorojas.bsky.social · 12h

vertebrae and a single caudal vertebra, which all belong to the same individual. More recently, in 2024, and earlier this year Jorge Gustavo Meso and his colleagues described various alvarezsaurid material that was assigned to Bonapartenykus ultimus, first reported in the late 2000s from the

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joshuapaleorojas.bsky.social @joshuapaleorojas.bsky.social · 12h

clues about the reproductive strategies of alvarezsaurids. Additionally, there are two other specimens that were referred to Bonapartenykus: labeled MGPIFD-GR 166 and MGPIFD-GR 184; consisting of a blade of the left scapula, a left coracoid, a distal right pubis, four cervical

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joshuapaleorojas.bsky.social @joshuapaleorojas.bsky.social · 12h

the pubic peduncle of the ilium, the anterior blade of the left ilium, and the two partially preserved eggs were separated from the holotype by less than 20 centimeters (7.9 inches). Interestingly, the specimen discovered with the eggs was female, which offers

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joshuapaleorojas.bsky.social @joshuapaleorojas.bsky.social · 12h

and named in 2012 by Federico L. Agnolin, Jaime E. Powell, Fernando E. Novas, and Martin Kundrát. Their holotype specimen - labeled MPCA, 1290 - consists of a mid-dorsal vertebra, both scapulocoracoids, left tibia, and femur, left pubis articulated with

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joshuapaleorojas.bsky.social @joshuapaleorojas.bsky.social · 12h

discovered in fluvial sandstones, located in northwestern Patagonia, Argentina (upper Allen Formation). They consisted of a partial skeleton with eggs, identified as a theropod that was originally described as an indeterminate alvarezsaurid, by Salgado et al., in 2009. It was later redescribed

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joshuapaleorojas.bsky.social @joshuapaleorojas.bsky.social · 12h

The first image is a spectacular reconstruction of the alvarezsauroid dinosaur, Bonapartenykus ultimus; by the talented artist @somniosa.bsky.social. The first fossilized remains to be unearthed for Bonapartenykus ultimus were

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joshuapaleorojas.bsky.social @joshuapaleorojas.bsky.social · 6d

can we care. Only if we care, we will help. Only if we help, we shall be saved."

"What you do makes a difference, and you have to decide what kind of difference you want to make."

joshuapaleorojas.bsky.social @joshuapaleorojas.bsky.social · 6d

It's extremely saddening to hear the loss of the greatest primatologist of my lifetime, Jane Goodall. Who died yesterday at the age of 91, she will forever be one of my favorite wildlife heroes. 🥰🥺🦍🦧🐒 "Only if we understand,

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Reposted

Thomas R. Holtz, Jr. @arctomet.bsky.social · 10d

Cretaceous sea turtle soft tissues clarify ancestry of scale loss in chelonioids: iScience www.cell.com/iscience/ful...

Cretaceous sea turtle soft tissues clarify ancestry of scale loss in chelonioids

Kear et al. describe the oldest fossil sea turtle soft tissues. These reveal the repeated evolution of scale-less skin as a hydrodynamic adaptation for oceanic lifestyles in chelonioids.

www.cell.com

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joshuapaleorojas.bsky.social @joshuapaleorojas.bsky.social · 17d

antiquitatis; displayed at the Toulouse Natural History Museum (MHNT), located in the Jardin des Plantes in Toulouse, in the Busca-Montplaisir district, France. The third image shows a cast of the mummified Starunia specimen, displayed at the Natural History Museum, located in London, England. 🤓🦣🦏

joshuapaleorojas.bsky.social @joshuapaleorojas.bsky.social · 17d

to become fragmented and less suitable, while low-level hunting by humans further weakened their populations, preventing their recovery and ultimately driving them to extinction around 10,000 years ago. The second image shows a skeleton of Coelodonta

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