A new goniopholidid from the Upper Jurassic Morrison Formation, USA: novel insight into aquatic adaptation toward modern crocodylians

Goniopholididae is a group of basal neosuchian crocodyliforms closely related to Paralligatoridae and Eusuchia that lived during the Jurassic and Early Cretaceous. Goniopholidids have the long, flat snout and secondary palate of modern crocodylians, the acquisition of which is regarded as a key feature in the early evolution of crocodylian body plan and their aquatic adaptation. Here, we report a new species, Amphicotylus milesi , with the description from the best-preserved specimen to date of Goniopholididae from Wyoming, USA. Its posterior extension of the nasopharyngeal passage (pterygoid secondary palate) and the shortening and dorsal deflection of the ceratobranchial suggest that basal neosuchians could raise their gular valve to separate oral and pharyngeal cavities as in modern crocodylians. The anatomy of Amphicotylus milesi sheds light on the acquisition of this new respiratory system in the crocodyliform evolution and their early aquatic adaptation, leading to modern crocodylians.

Loss of olfaction in sea snakes provides new perspectives on the aquatic adaptation of amniotes

Marine amniotes, a polyphyletic group, provide an excellent opportunity for studying convergent evolution. Their sense of smell tends to degenerate, but this process has not been explored by comparing fully aquatic species with their amphibious relatives in an evolutionary context. Here, we sequenced the genomes of fully aquatic and amphibious sea snakes and identified repertoires of chemosensory receptor genes involved in olfaction. Snakes possess large numbers of the olfactory receptor ( OR ) genes and the type-2 vomeronasal receptor ( V2R ) genes, and expression profiling in the olfactory tissues suggests that snakes use the ORs in the main olfactory system (MOS) and the V2Rs in the vomeronasal system (VNS). The number of OR genes has decreased in sea snakes, and fully aquatic species lost MOS which is responsible for detecting airborne odours. By contrast, sea snakes including fully aquatic species retain a number of V2R genes and a well-developed VNS for smelling underwater. This study suggests that the sense of smell also degenerated in sea snakes, particularly in fully aquatic species, but their residual olfactory capability is distinct from that of other fully aquatic amniotes. Amphibious species show an intermediate status between terrestrial and fully aquatic snakes, implying their importance in understanding the process of aquatic adaptation.

Neurovascular anatomy of the protostegid turtle Rhinochelys pulchriceps and comparisons of membranous and endosseous labyrinth shape in an extant turtle

Chelonioid turtles are the only surviving group of reptiles that secondarily evolved marine lifestyles during the Mesozoic Early chelonioid evolution is documented by fossils of their stem group, such as protostegids, which yield insights into the evolution of marine adaptation. Neuroanatomical features are commonly used to infer palaeoecology owing to the functional adaptation of the senses of an organism to its environment. We investigated the neuroanatomy and carotid circulation of the early Late Cretaceous protostegid Rhinochelys pulchriceps based on micro-computed tomography data. We show that the trigeminal foramen of turtles is not homologous to that of other reptiles. The endosseous labyrinth of R. pulchriceps has thick semicircular canals and a high aspect ratio. Comparisons among turtles and other reptiles show that the endosseous labyrinth aspect ratio is not a reliable predictor of the degree of aquatic adaptation, contradicting previous hypotheses. We provide the first models of neuroanatomical soft tissues of an extant turtle. Turtle brain morphology is not reflected by the brain cavity, and the endosseous labyrinth provides an incomplete reflection of membranous semicircular duct morphology. Membranous labyrinth geometry is conserved across gnathostomes, which allows approximate reconstruction of the total membranous labyrinth morphology from the endosseous labyrinth despite their poor reflection of duct morphology.

Aquatic Adaptation and Depleted Diversity: A Deep Dive into the Genomes of the Sea Otter and Giant Otter

Despite its recent invasion into the marine realm, the sea otter (Enhydra lutris) has evolved a suite of adaptations for life in cold coastal waters, including limb modifications and dense insulating fur. This uniquely dense coat led to the near-extinction of sea otters during the 18th–20th century fur trade and an extreme population bottleneck. We used the de novo genome of the southern sea otter (E. l. nereis) to reconstruct its evolutionary history, identify genes influencing aquatic adaptation, and detect signals of population bottlenecks. We compared the genome of the southern sea otter with the tropical freshwater-living giant otter (Pteronura brasiliensis) to assess common and divergent genomic trends between otter species, and with the closely related northern sea otter (E. l. kenyoni) to uncover population-level trends. We found signals of positive selection in genes related to aquatic adaptations, particularly limb development and polygenic selection on genes related to hair follicle development. We found extensive pseudogenization of olfactory receptor genes in both the sea otter and giant otter lineages, consistent with patterns of sensory gene loss in other aquatic mammals. At the population level, the southern sea otter and the northern sea otter showed extremely low genomic diversity, signals of recent inbreeding, and demographic histories marked by population declines. These declines may predate the fur trade and appear to have resulted in an increase in putatively deleterious variants that could impact the future recovery of the sea otter.

Educación acuasomática: beneficios de las competencias filogenéticas en natación para bebés

Antecedentes: La Escuela de Natación Acuarela (Oaxaca-México) adoptó la teoría de la Tritemporalidad de la Motricidad Humana (filogénesis, ontogénesis y sociogénesis) para desarrollar su método de enseñanza en la Educación Acuasomática para bebés, en donde, para facilitar el proceso de aprendizaje, recurre a las competencias filogenéticas.Objetivos: Explorar si el método de Educación Acuasomática de la Escuela Acuarela, propicia que la madre experimente y se haga consciente de sus competencias en el agua y si esto facilita que el bebé adquiera habilidades fundamentales para interrelacionarse naturalmente con el agua.Método: Metodología mixta para evaluar el desarrollo de cinco competencias filogenéticas: atención sustentada, gestualización, interacción, afiliación e imitación durante el proceso enseñanza-aprendizaje. Curso de 3 meses con 14 diadas (madres-bebés) menores de 1 año. Utiliza: entrevista, encuesta (pre-test/post-test), videograbación y auto-observación de las madres.Resultados: Inicialmente, 20% de las madres reportan no saber nadar, 58% haber tenido poco contacto con agua en la niñez y 30% algo de miedo. A lo largo de las sesiones, exploran, de manera teórico-vivencial y progresiva, las nociones de la Tritemporalidad de la Motricidad Humana y sus competencias filogenéticas; todas mostraron un incremento progresivo. Su autobservación conlleva un aumento de emociones positivas en relación con su experiencia en el agua. Señalan gran satisfacción con la escuela y metodología implementada.Conclusiones: La Educación Acuasomática prepara a la madre para abordar conscientemente las competencias filogenéticas que garantizan en el bebé la adquisición de habilidades básicas para su adaptación natural al agua y facilitar el aprendizaje de la natación.Palabras clave: Agua, Educación Somática, Habilidad, Maternal, Aprendizaje, Natación, Bebés, México. Title: Acuasomatic education: Benefits of phylogenetic competences in swimming for babiesAbstract Introduction: The Acuarela Swim School (Oaxaca-Mexico) has adopted the theory of the tritemporality of Human Motricity (phylogenesis, ontogenesis and sociogenesis) to develop its teaching method in Aquasomatic Education for babies, in which, in order to facilitate the learning process, turns to the phylogenetic competences.Goals: To explore whether the method of Aquasomatic Education of the Acuarela School propitiates a context in which the mother experiments and becomes conscious of her competences in the water and if this facilitates the baby’s acquisition of fundamental abilities to interrelate with the water.Method: Mixed methodology to evaluate the development of five phylogenetic competences: sustained attention, gestualization, interaction, affiliation and imitation during the teaching-learning process. Three-month course with 14 dyads (mothers-babies) less than one year old. Uses: interview, survey (pretest/posttest), video-recordings and self-observation of the mothers.Results: Initially, 20% of the mothers reported not knowing how to swim, 58% had little contact with water during their childhood and 30% have some fear. Throughout the sessions, they explore, in theoretical-experiential and progressive ways; all showed progressive increments. Their self-observations reflect a rise in positive emotions in terms of their experience in the water. They show great satisfaction with the school and the methodology that has been implemented.Conclusions: Aquasomatic Education prepares the mother to approach consciously the phylogenetic competences that guarantee the baby’s acquisition of basic abilities for its natural adaptation to the water and facilitate learning to swim.Keywords: Somatic Education, Maternal, Skills, Aquatic Adaptation, Baby, Mexico. Titulo: Educação de Acuasomatic: Benefícios de competências filogenéticas na natação para bebêsResumoIntrodução: A Escola de Natação Acuarela (Oaxaca-México), adotou a teoria da Tritemporalidade da Motricidade Humana (filogênese, ontogênese e sociogênese) para desenvolver seu método de ensino na educação aquática para bebês, onde, para facilitar o processo de aprendizagem, recorre as competências filogenéticas.Objetivos: explorar se o método do Educação Aquasomática da Escola Acuarela, incentiva as mães a experimentar e tomar consciência de suas próprias habilidades na água e se isso permite que o bebê adquira habilidades fundamentais para se inter-relacionar naturalmente com a água.Método: metodologia mista para avaliar o desenvolvimento de cinco competências filogenéticas: atenção sustentada, gestualização, interação, afiliação e imitação durante o processo de ensino-aprendizagem. Curso de 3 meses com 14 duplas (mães e bebês) com menos de 1 ano. Se utilizou: entrevista, pesquisa (pré-teste / pós-teste), gravação de vídeo e auto-observação das mães.Resultados: Inicialmente, 20% das mães relataram não saber como nadar, 58% tiveram pouco contato com a água na infância e 30% tiveram algum medo. Ao longo das sessões, exploraram, de maneira teórico-experimental e progressiva, as noções de Tritemporalidade da Motricidade Humana e suas competências filogenéticas; Todas mostraram um aumento progressivo. A sua auto-observação leva a um aumento das emoções positivas em relação à sua experiência na água. Elas indicam grande satisfação com a escola e metodologia implementada.Conclusiones: A Educação Aquasomática prepara a mãe para abordar conscientemente as competências filogenéticas que garantem ao bebê a aquisição de habilidades básicas para a sua adaptação natural à água e facilitar a aprendizagem da nataçãoPalavras-chave: Água, Educação Somática, Habilidade, Materna, Aprendizagem, Natação de Bebês, México.