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   https://doi.org/10.1002/ar.25160  

   Pritchard, Adam C. ; Irmis, Randall B. ; Olori, Jennifer C. ; Nesbitt, Sterling J. ; Smith, Nathan D. ; Stocker, Michelle R. ; Turner, Alan H. ( February 2023 , The Anatomical Record)

   The femora of diapsids have undergone morphological changes related to shifts in postural and locomotor modes, such as the transition from plesiomorphic amniote and diapsid taxa to the apomorphic conditions related to a more erect posture within Archosauriformes. One remarkable clade of Triassic diapsids is the chameleon‐like Drepanosauromorpha. This group is known from numerous articulated but heavily compressed skeletons that have the potential to further inform early reptile femoral evolution. For the first time, we describe the three‐dimensional osteology of the femora of Drepanosauromorpha, based on undistorted fossils from the Upper Triassic Chinle Formation and Dockum Group of North America. We identify apomorphies and a combination of character states that link these femora to those in crushed specimens of drepanosauromorphs and compare our sample with a range of amniote taxa. Several characteristics of drepanosauromorph femora, including a hemispherical proximal articular surface, prominent asymmetry in the proximodistal length of the tibial condyles, and a deep intercondylar sulcus, are plesiomorphies shared with early diapsids. The femora contrast with those of most diapsids in lacking a crest‐like, distally tapering internal trochanter. They bear a ventrolaterally positioned tuberosity on the femoral shaft, resembling the fourth trochanter in Archosauriformes. The reduction of an internal trochanter parallels independent reductions in therapsids and archosauriforms. The presence of a ventrolaterally positioned trochanter is also similar to that of chameleonid squamates. Collectively, these features demonstrate a unique femoral morphology for drepanosauromorphs, and suggest an increased capacity for femoral adduction and protraction relative to most other Permo‐Triassic diapsids.

    

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2. The EICA is dead? Long live the EICA !

   https://doi.org/10.1111/ele.14088  

   Callaway, Ragan M. ; Lucero, Jacob E. ; Hierro, José L. ; Lortie, C. J. ( October 2022 , Ecology Letters)
3. Neogene sloth assemblages ( M ammalia, P ilosa) of the C ocinetas B asin ( L a G uajira, C olombia): implications for the G reat A merican B iotic I nterchange

   https://doi.org/10.1111/pala.12244  

   Amson, Eli ; Carrillo, Juan_D ; Jaramillo, Carlos ; O'Regan, ed., Hannah ( June 2016 , Palaeontology)

   We describe sloth assemblages from theCocinetasBasin (LaGuajira peninsula,Colombia), found in theNeogeneCastilletes andWare formations, located in northernmostSouthAmerica, documenting otherwise poorly known biotas. The tentative referral of a specimen to a small megatherioid sloth,Hyperleptus?, from the early–middleMioceneCastilletesFormation, suggests affinities of this fauna with the distantSantaCruzFormation and documents a large latitudinal distribution for this taxon. The latePlioceneWareFormation is much more diverse, with five distinct taxa representing every family of ‘ground sloths’. This diversity is also remarkable at the ecological level, with sloths spanning over two orders of magnitude of body mass and probably having different feeding strategies. Being only a few hundred kilometres away from theIsthmus ofPanama, and a few hundred thousand years older than the classically recognized first main pulse of theGreatAmericanBiotic interchange (GABI1), theWareFormation furthermore documents an important fauna for the understanding of this major event inNeogene palaeobiogeography. The sloths for which unambiguous affinities were recovered are not closely related to the early immigrants found inNorthAmerica beforeGABI1.

    

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4. The Movement Ecology of Mutualism ( CSEE / ESA 2022, OOS17 )

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   Moore, Christopher M. ; Shaw, Allison K. ; Bruninga‐Socolar, Bethanne ; Caves, Eleanor M. ; Karnish, Alex T. ; Kiesewetter, Kasey N. ; Nelson, Annika S. ; Pringle, Elizabeth G. ( April 2023 , The Bulletin of the Ecological Society of America)
5. Equatorial K elvin waves generated in the western tropical P acific O cean trigger mass and heat transport within the M iddle A merica T rench off C osta R ica

   https://doi.org/10.1002/2017JC012848  

   Thomson, Richard E. ; Davis, Earl E. ( July 2017 , Journal of Geophysical Research: Oceans)