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Current Biology : CB Mar 2013Most small children can tell you that 'reptiles' are the snakes, lizards, crocodiles, and turtles (perhaps with the dinosaurs thrown in) - suggesting that it's easy to... (Review)
Review
Most small children can tell you that 'reptiles' are the snakes, lizards, crocodiles, and turtles (perhaps with the dinosaurs thrown in) - suggesting that it's easy to tell the difference between reptiles and other animals. Unfortunately, evolutionary biologists struggle with the same task, because phylogenetic analysis tells us loud and clear that these different types of what we loosely call 'reptiles' are not particularly closely related to each other (Figure 1). On the evolutionary tree, some of them (dinosaurs, crocodiles) are much more closely related to birds than to the other animals that we call reptiles. Other reptiles are the descendants of very ancient lineages; for example, turtles separated from the other reptiles, including the now-dominant Squamata (lizards and snakes), at least 200 million years ago. And another 200-million-year-old lineage has left just a single survivor, a lizard-like creature (the tuatara), on a few islands in New Zealand.
Topics: Animals; Biodiversity; Biological Evolution; Conservation of Natural Resources; Reproduction; Reptiles
PubMed: 23518049
DOI: 10.1016/j.cub.2013.02.024 -
Current Biology : CB May 2023In the early 19th century, long before the discovery of the dinosaurs, scientists and the public alike were faced with the realization that strange beasts, wholly...
In the early 19th century, long before the discovery of the dinosaurs, scientists and the public alike were faced with the realization that strange beasts, wholly extinct, were once populating Earth's ancient oceans. In no small part, this realization was through the discovery of the first plesiosaurs (and ichthyosaurs) along the Dorset coast of England in the seaside town of Lyme Regis. There was this large marine reptile resembling a large sea turtle, but with four evenly shaped flippers and looking as though a large snake had been pulled through its carapace. It was soon to be named scientifically Plesiosaurus, in reference to its greater similarity to living reptiles than the Ichthyosaurus (Figure 1). While the Ichthyosaurus was relatively easily understood as a fish-shaped reptile descended from land-living ancestors, the Plesiosaurus was beyond comprehension, even though incomplete skeletons had been unearthed already in the early 18th century. Plesiosaurs seemed so alien that the first complete skeleton, discovered by the famed Mary Anning a little more than 200 years ago (Figure 1A), was considered a fake by the leading anatomist of the day, the Baron Georges Cuvier in Paris. Only study of the original specimen convinced him of the authenticity of this animal but reinforced his seminal insight that there is extinction.
Topics: Animals; Male; Animal Shells; Dinosaurs; England; Environment
PubMed: 37220726
DOI: 10.1016/j.cub.2023.04.018 -
Genes Aug 2019In this contribution, the aspects of reptile and amphibian speciation that emerged from research performed over the past decade are reviewed. First, this study assesses... (Review)
Review
In this contribution, the aspects of reptile and amphibian speciation that emerged from research performed over the past decade are reviewed. First, this study assesses how patterns and processes of speciation depend on knowing the taxonomy of the group in question, and discuss how integrative taxonomy has contributed to speciation research in these groups. This study then reviews the research on different aspects of speciation in reptiles and amphibians, including biogeography and climatic niches, ecological speciation, the relationship between speciation rates and phenotypic traits, and genetics and genomics. Further, several case studies of speciation in reptiles and amphibians that exemplify many of these themes are discussed. These include studies of integrative taxonomy and biogeography in South American lizards, ecological speciation in European salamanders, speciation and phenotypic evolution in frogs and lizards. The final case study combines genomics and biogeography in tortoises. The field of amphibian and reptile speciation research has steadily moved forward from the assessment of geographic and ecological aspects, to incorporating other dimensions of speciation, such as genetic mechanisms and evolutionary forces. A higher degree of integration among all these dimensions emerges as a goal for future research.
Topics: Amphibians; Animals; Ecosystem; Evolution, Molecular; Genetic Speciation; Reptiles; Selection, Genetic
PubMed: 31455040
DOI: 10.3390/genes10090646 -
Philosophical Transactions of the Royal... Mar 2020The Archosauria are a highly successful group of vertebrates, and their evolution is marked by the appearance of diverse respiratory and metabolic strategies. This... (Review)
Review
The Archosauria are a highly successful group of vertebrates, and their evolution is marked by the appearance of diverse respiratory and metabolic strategies. This review examines respiratory function in living and fossil archosaurs, focusing on the anatomy and biomechanics of the respiratory system, and their physiological consequences. The first archosaurs shared a heterogeneously partitioned parabronchial lung with unidirectional air flow; from this common ancestral lung morphology, we trace the diverging respiratory designs of bird- and crocodilian-line archosaurs. We review the latest evidence of osteological correlates for lung structure and the presence and distribution of accessory air sacs, with a focus on the evolution of the avian lung-air sac system and the functional separation of gas exchange and ventilation. In addition, we discuss the evolution of ventilation mechanics across archosaurs, citing new biomechanical data from extant taxa and how this informs our reconstructions of fossils. This improved understanding of respiratory form and function should help to reconstruct key physiological parameters in fossil taxa. We highlight key events in archosaur evolution where respiratory physiology likely played a major role, such as their radiation at a time of relative hypoxia following the Permo-Triassic mass extinction, and their evolution of elevated metabolic rates. This article is part of the theme issue 'Vertebrate palaeophysiology'.
Topics: Alligators and Crocodiles; Animals; Biological Evolution; Birds; Fossils; Reptiles; Respiration
PubMed: 31928195
DOI: 10.1098/rstb.2019.0140 -
PLoS Neglected Tropical Diseases Jul 2023The world-famous markets of Marrakech, also known in Arabic as souks, harbor a vast diversity of reptiles that are sold for medicinal/magic/pet purposes or used for...
The world-famous markets of Marrakech, also known in Arabic as souks, harbor a vast diversity of reptiles that are sold for medicinal/magic/pet purposes or used for snake charming. This unique epidemiological context has never been studied considering the interactions of humans, reptiles, and zoonotic pathogens. Thus, the aim of this study was to identify the parasites and pathogens present in blood and feces associated with handled reptiles in the markets of Marrakech to assess the risk of zoonotic transmission within the reptile-human interface. Privately owned reptiles (n = 118), coming from vendors or snake charmers, were examined and blood and feces sampled. DNA was extracted and molecular screening (cPCR, nPCR, qPCR, dqPCR) was performed aiming to identify potentially zoonotic pathogens (i.e., Anaplasma/Ehrlichia spp., Rickettsia spp., Borrelia burgdorferi sensu lato, Coxiella burnetii, Babesia/Theileria spp., Cryptosporidium spp., Giardia spp., Leishmania spp., Cestoda). Overall, 28.9% (34/118) of reptiles were positive for at least one pathogen. In blood, Anaplasma spp. were detected in four snakes, with two Montpellier snakes positive for Anaplasma phagocytophilum, while Rickettsia spp. were detected in one Mediterranean chameleon and four puff adders. Leishmania tarentolae was molecularly detected in a Mediterranean chameleon and a Montpellier snake. In feces, the cox1 gene generated a myriad of sequences for nematodes, cestodes, fungi and bacteria. Importantly, Proteus vulgaris was identified from a Mediterranean chameleon. Cryptosporidium spp. nPCR yielded a positive sample (i.e., Cryptosporidium sp. apodemus genotype I) from a Moroccan worm lizard, as well as for bacteria such as Pseudomonas aeruginosa in an Egyptian cobra, and Morganella morganii from a puff adder. Results from this study demonstrated the risk of zoonotic transmission of microorganisms and parasites present in blood and feces from reptiles that are brought to the souks in Marrakech, Morocco, to be sold for medicinal purposes or used for snake charming, being in direct and straight contact with humans.
Topics: Animals; Humans; Cryptosporidiosis; Morocco; Cryptosporidium; Rickettsia; Parasites; Anaplasma; Snakes; Reptiles
PubMed: 37467211
DOI: 10.1371/journal.pntd.0011431 -
Viruses Nov 2011A large number of viruses have been described in many different reptiles. These viruses include arboviruses that primarily infect mammals or birds as well as viruses... (Review)
Review
A large number of viruses have been described in many different reptiles. These viruses include arboviruses that primarily infect mammals or birds as well as viruses that are specific for reptiles. Interest in arboviruses infecting reptiles has mainly focused on the role reptiles may play in the epidemiology of these viruses, especially over winter. Interest in reptile specific viruses has concentrated on both their importance for reptile medicine as well as virus taxonomy and evolution. The impact of many viral infections on reptile health is not known. Koch's postulates have only been fulfilled for a limited number of reptilian viruses. As diagnostic testing becomes more sensitive, multiple infections with various viruses and other infectious agents are also being detected. In most cases the interactions between these different agents are not known. This review provides an update on viruses described in reptiles, the animal species in which they have been detected, and what is known about their taxonomic positions.
Topics: Animals; Reptiles; Virus Diseases; Virus Physiological Phenomena; Viruses
PubMed: 22163336
DOI: 10.3390/v3112087 -
International Journal of Molecular... Jun 2019Reptiles are a rare model object for space research. However, some reptile species demonstrate effective adaptation to spaceflight conditions. The main scope of this... (Review)
Review
Reptiles are a rare model object for space research. However, some reptile species demonstrate effective adaptation to spaceflight conditions. The main scope of this review is a comparative analysis of reptile experimental exposure in weightlessness, demonstrating the advantages and shortcomings of this model. The description of the known reptile experiments using turtles and geckos in the space and parabolic flight experiments is provided. Behavior, skeletal bones (morphology, histology, and X-ray microtomography), internal organs, and the nervous system (morphology, histology, and immunohistochemistry) are studied in the spaceflight experiments to date, while molecular and physiological results are restricted. Therefore, the results are discussed in the scope of molecular data collected from mammalian (mainly rodents) specimens and cell cultures in the parabolic and orbital flights and simulated microgravity. The published data are compared with the results of the gecko model studies after the 12-44.5-day spaceflights with special reference to the unique peculiarities of the gecko model for the orbital experiments. The complex study of thick-toed geckos after three spaceflights, in which all geckos survived and demonstrated effective adaptation to spaceflight conditions, was performed. However, future investigations are needed to study molecular mechanisms of gecko adaptation in space.
Topics: Adaptation, Physiological; Animals; Bone and Bones; Brain; Lizards; Reptiles; Space Flight; Turtles; Weightlessness Simulation
PubMed: 31226840
DOI: 10.3390/ijms20123019 -
PeerJ 2022Declines of large-bodied herbivorous reptiles are well documented, but the consequences for ecosystem function are not. Understanding how large-bodied herbivorous...
BACKGROUND
Declines of large-bodied herbivorous reptiles are well documented, but the consequences for ecosystem function are not. Understanding how large-bodied herbivorous reptiles engineer ecosystems is relevant given the current interest in restoration of tropical islands where extinction rates are disproportionately high and reptiles are prominent as herbivores.
METHODS
In this study, we measured the ecosystem-level outcomes of long-term quasi-experiment represented by two adjacent islands within the Galapagos Archipelago, one with and the other without Galapagos land iguanas (), large-bodied herbivores known to feed on many plant species. We characterized plant communities on each island by developing high-resolution (<1 cm) aerial imagery and delineating extent of plant associations and counting individual plants on each.
RESULTS
In the presence of iguanas there was dramatically less woody plant cover, more area with seasonal grasses, and many fewer cacti. Cacti had a more clumped distribution where iguanas were absent than where iguanas were present.
DISCUSSION
This study provided strong evidence that Galapagos land iguanas can substantially engineer the structure of terrestrial plant communities; therefore, restoration of large-bodied reptilian herbivores, such as land iguanas and giant tortoises, should be regarded as an important component of overall ecosystem restoration, especially for tropical islands from which they have been extirpated.
Topics: Animals; Iguanas; Ecosystem; Lizards; Plants; Turtles
PubMed: 35116195
DOI: 10.7717/peerj.12711 -
Trends in Parasitology Aug 2020Reptiles are reservoirs of a wide range of pathogens, including many protozoa, helminths, pentastomids, and arthropod parasitic species, some of which may be of public... (Review)
Review
Reptiles are reservoirs of a wide range of pathogens, including many protozoa, helminths, pentastomids, and arthropod parasitic species, some of which may be of public health concern. In this review we discuss the zoonotic risks associated with human-reptile interactions. Increased urbanization and introduction of exotic species of reptile may act as drivers for the transmission of zoonotic parasites through the environment. In addition, being a part of human diet, reptiles can be a source of life-threatening parasitoses, such as pentastomiasis or sparganosis. Finally, reptiles kept as pets may represent a risk to owners given the possibility of parasites transmitted by direct contact or fecal contamination. Awareness of reptile-borne zoonotic parasitoses is important to advocate control, prevention, and surveillance of these neglected diseases.
Topics: Animals; Food Parasitology; Humans; Parasites; Parasitic Diseases; Pets; Reptiles; Zoonoses
PubMed: 32448703
DOI: 10.1016/j.pt.2020.04.014 -
Nature Communications Oct 2020Despite considerable advances in knowledge of the anatomy, ecology and evolution of early mammals, far less is known about their physiology. Evidence is contradictory...
Despite considerable advances in knowledge of the anatomy, ecology and evolution of early mammals, far less is known about their physiology. Evidence is contradictory concerning the timing and fossil groups in which mammalian endothermy arose. To determine the state of metabolic evolution in two of the earliest stem-mammals, the Early Jurassic Morganucodon and Kuehneotherium, we use separate proxies for basal and maximum metabolic rate. Here we report, using synchrotron X-ray tomographic imaging of incremental tooth cementum, that they had maximum lifespans considerably longer than comparably sized living mammals, but similar to those of reptiles, and so they likely had reptilian-level basal metabolic rates. Measurements of femoral nutrient foramina show Morganucodon had blood flow rates intermediate between living mammals and reptiles, suggesting maximum metabolic rates increased evolutionarily before basal metabolic rates. Stem mammals lacked the elevated endothermic metabolism of living mammals, highlighting the mosaic nature of mammalian physiological evolution.
Topics: Animals; Basal Metabolism; Biological Evolution; Fossils; History, Ancient; Mammals; Phylogeny; Reptiles; Tomography, X-Ray; Tooth
PubMed: 33046697
DOI: 10.1038/s41467-020-18898-4