Cranial ecomorphology of turtles and neck retraction as a possible trigger of ecological diversification

Evolution, Journal Year: 2022, Volume and Issue: 76(11), P. 2566 - 2586

Published: Sept. 19, 2022

Turtles have a highly modified body plan, including rigid shell that constrains postcranial anatomy. Skull morphology and neck mobility may therefore be key to ecological specialization in turtles. However, the signal of turtle skull morphologies has not been rigorously evaluated, leaving uncertainties about roles adaptation convergence. We evaluate cranial ecomorphology using three-dimensional geometric morphometrics phylogenetic comparative methods. shape correlates with allometry, retraction capability, different aquatic feeding ecologies. find variables influence only, whereas functional variable (the capacity for retraction) influences both size. Ecology predictions from are validated by high success rates extant species, outperforming previous two-dimensional approaches. use this infer traits extinct species. Neck evolved among crownward stem-turtles Late Jurassic, signaling decoupling shell, possibly linked major episode ecomorphological diversification. also strong evidence convergent adaptations marine groups. This includes parallel loss retraction, active hunting, possible grazing, suction Our large-scale assessment dietary throughout evolution reveals timing origin their distinct ecomorphologies, highlights potential ecology function effects on form.

Language: Английский

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Independent origin of large labyrinth size in turtles

Nature Communications, Journal Year: 2022, Volume and Issue: 13(1)

Published: Oct. 11, 2022

Abstract The labyrinth of the vertebrate inner ear is a sensory system that governs perception head rotations. Central hypotheses predict shape and size are related to ecological adaptations, but this under debate has rarely been tested outside mammals. We analyze evolution morphology its drivers in living fossil turtles, an understudied group underwent multiple locomotory transitions during 230 million years evolution. show turtles have unexpectedly large labyrinths evolved origin aquatic habits. Turtle relatively larger than those mammals, comparable many birds, undermining hypothesis correlates directly with agility across vertebrates. also find variation does not correlate ecology widespread expectation reptilian shapes convey behavioral signal, demonstrating importance groups, like turtles.

Language: Английский

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A systematic compendium of turtle mandibular anatomy using digital dissections of soft tissue and osteology

The Anatomical Record, Journal Year: 2022, Volume and Issue: 306(6), P. 1228 - 1303

Published: July 28, 2022

Abstract Turtles are a charismatic reptile group with peculiar body plan, which most notably includes the shell. Anatomists have often focused descriptive efforts on shell and other strongly derived parts, such as akinetic skull, or cervical vertebrae. Other parts of turtle osteology, like girdles, limbs, mandibles, documented less rigor detail. The mandible is primary skeletal element involved in food acquisition initial processing turtles, its features thus likely linked to feeding ecology. In addition, turtles composed up seven bones (sometimes fused little three) has anatomical complexity that may be insightful for systematic purposes phylogenetic research. Despite apparent diversity this system not been systematically studied, even search characters might improve resolution. Here, we describe mandibular osteology all major subclades extant help digitally dissected 3D models from high‐resolution computed tomography (μCT) scans 70 species. We provide 31 fully segmented well musculature, innervation, arterial circulation cryptodire Dermatemys mawii . synthesize observed variation into 51 morphological characters, optimize onto molecular phylogeny. This analysis shows some high value, whereas others highly homoplastic underlie ecological influences factors invoking variation.

Language: Английский

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The first neuroanatomical study of a marine pleurodire (the large Paleocene bothremydid Azzabaremys moragjonesi) reveals convergences with other clades of pelagic turtles

Fossil record, Journal Year: 2025, Volume and Issue: 28(1), P. 1 - 15

Published: Jan. 3, 2025

Azzabaremys moragjonesi , from the Paleocene of Mali, is a member Nigeremydini. This clade bothremydid pleurodiran turtles that includes large putatively marine forms which inhabited African Trans-Saharian Seaway Maastrichtian to Paleocene. work represents first neuroanatomical reconstruction putative sea pleurodire. Some modifications observed for differ those in other lineages Bothremydidae these structures have been documented, corresponding freshwater instead pelagic forms. In fact, primitive condition Pleurodira adaptation environments, as case with all extant representatives, but also most documented extinct The neuroanatomy shows convergences members Pan-Cryptodira adaptations environments (i.e., Chelonioidea, including Cheloniidae and Dermochelyidae), clades exclusive fossil record several Mesozoic Palaeogene uncertain affiliations: Plesiochelyidae, Sandownidae, Protostegidae). Thus, aspects such position geniculate ganglion into canalis cavernosus, absence an anterior vidian canal piercing pterygoid, possession wide semicircular canals endosseous labyrinth, well possible presence enlarged lacrimal glands, are recognized here convergent developed Cryptodira, affiliations, response environments.

Language: Английский

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The first neuroanatomical study of a marine pleurodire (the large Paleocene bothremydid Azzabaremys moragjonesi) reveals convergences with other clades of pelagic turtles

Fossil record, Journal Year: 2025, Volume and Issue: 28(1), P. 1 - 15

Published: Jan. 3, 2025

Azzabaremys moragjonesi , from the Paleocene of Mali, is a member Nigeremydini. This clade bothremydid pleurodiran turtles that includes large putatively marine forms which inhabited African Trans-Saharian Seaway Maastrichtian to Paleocene. work represents first neuroanatomical reconstruction putative sea pleurodire. Some modifications observed for differ those in other lineages Bothremydidae these structures have been documented, corresponding freshwater instead pelagic forms. In fact, primitive condition Pleurodira adaptation environments, as case with all extant representatives, but also most documented extinct The neuroanatomy shows convergences members Pan-Cryptodira adaptations environments (i.e., Chelonioidea, including Cheloniidae and Dermochelyidae), clades exclusive fossil record several Mesozoic Palaeogene uncertain affiliations: Plesiochelyidae, Sandownidae, Protostegidae). Thus, aspects such position geniculate ganglion into canalis cavernosus, absence an anterior vidian canal piercing pterygoid, possession wide semicircular canals endosseous labyrinth, well possible presence enlarged lacrimal glands, are recognized here convergent developed Cryptodira, affiliations, response environments.

Language: Английский

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Wabanbara ringtailensis —a new chelid turtle (Pleurodira: Chelidae) from mid-Miocene deposits of the Riversleigh World Heritage Area in Australia

Alcheringa An Australasian Journal of Palaeontology, Journal Year: 2025, Volume and Issue: unknown, P. 1 - 16

Published: March 30, 2025

Language: Английский

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A new pelomedusoid turtle,Sahonachelys mailakavava, from the Late Cretaceous of Madagascar provides evidence for convergent evolution of specialized suction feeding among pleurodires

Royal Society Open Science, Journal Year: 2021, Volume and Issue: 8(5)

Published: May 1, 2021

The Maevarano Formation in northwestern Madagascar has yielded a series of exceptional fossils over the course last three decades that provide important insights into evolution insular ecosystems during latest Cretaceous (Maastrichtian). We here describe new genus and species pelomedusoid turtle from this formation, Sahonachelys mailakavava , based on nearly complete skeleton. A phylogenetic analysis suggests close affinities with coeval Madagascan Sokatra antitra . These two taxa are only known representatives newly recognized clade Sahonachelyidae which is sister to speciose formed by Bothremydidae Podocnemidoidae relationship Indian turtles Kurmademydini notably absent. functional assessment was specialized suction feeder preyed upon small-bodied invertebrates vertebrates. This unique feeding strategy among crown pelomedusoids convergent documented numerous other clades highlights distinct evolutionary pathways taken

Language: Английский

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Two turtles with soft tissue preservation from the platy limestones of Germany provide evidence for marine flipper adaptations in Late Jurassic thalassochelydians

PLoS ONE, Journal Year: 2021, Volume and Issue: 16(6), P. e0252355 - e0252355

Published: June 3, 2021

Late Jurassic deposits across Europe have yielded a rich fauna of extinct turtles. Although many these turtles are recovered from marine deposits, it is unclear which taxa habitually and may be riverine species washed into nearby basins, as adaptations to open conditions yet found. Two new fossils the Germany provide unusually strong evidence for adaptations. The first specimen partial shell articulated hind limb (early Tithonian) platy limestones Schernfeld near Eichstätt, preserves integument an imprint. skin fully covered by flat, polygonal scales, stiffen pes paddle. taxonomic attribution not possible, similarities apparent with Thalassemys. second large, skeleton hypertrophied limbs referable Thalassemys bruntrutana Kimmeridgian) limestone Wattendorf, Bamberg. Even though preserved phosphatic film, scales preserved. This can nevertheless inferred had paddles stiffened based on pose in they preserved, presence epibionts between digits, full morphological correspondence Schernfeld. An analysis scalation extant demonstrated that elongate flippers stiffed adaptation, contrast but flexible Phylogenetic suggests mostly turtle clade Thalassochelydia. adapted this taxon therefore evolved convergently those later clades thalassochelydian restricted Europe, one notable exception Argentina, their combined interconnectivity oceans predict must been even more wide-spread during time.

Language: Английский

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Neuroanatomical Study and Three-Dimensional Cranial Reconstruction of the Brazilian Albian Pleurodiran Turtle Euraxemys essweini

Diversity, Journal Year: 2023, Volume and Issue: 15(3), P. 374 - 374

Published: March 5, 2023

Pleurodira represent one of the two clades that compose crown Testudines, and their temporal range is Late Jurassic–present. However, knowledge about neuroanatomy extinct pleurodires still very limited. In this context, scarce neuroanatomical information Cretaceous clade Euraxemydidae currently available, limited to some characters Moroccan Cenomanian Dirqadim schaefferi. present work, we perform detailed study its sister taxon, Brazilian Albian Euraxemys essweini, based on analysis skull holotype only known individual species. The virtual three-dimensional reconstruction all cranial bones performed, also improving osseous anatomy. different cavities (i.e., cranial, nasal, labyrinthic ones) canals nervous circulatory are compared with those identified thus far for other extant members in order characterize detail.

Language: Английский

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Morphological Diversity of Turtle Hyoid Apparatus is Linked to Feeding Behavior

Integrative Organismal Biology, Journal Year: 2024, Volume and Issue: 6(1)

Published: Jan. 1, 2024

Synopsis The hyoid apparatus of tetrapods is highly diverse in its morphology. It plays an important role feeding, breathing, sound production, and various other behaviors. Among turtles, the diversity has been recurrently linked to their habitat. ossification corpus often main trait used correlations with “niche” occupancy, ossified being associated aquatic environments a cartilaginous terrestrial life. Most studies conducted so far have focused on species belonging Testudinoidea, clade that occupies biggest habitats (i.e., terrestrial, semi-terrestrial, animals), while turtle lineages largely understudied. We assessed adult anatomy 92 from all “families”, together sequences embryological series 11 species, some described for first time here. Using nearly 40 different discrete anatomical characters, we discuss evolutionary patterns biological significance morphological transformations elements. Morphological changes are strongly feeding modes, several instances convergent evolution within outside Testudines clade, not as connected habitat previously thought. Some character states describe diagnostic specific clades, thus providing phylogenetically relevant information.

Language: Английский

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