varanus komodoensis

The interplay between predator and prey has catalyzed the evolution of venom systems, with predators honing their venoms in response to the evolving resistance of prey. A previous study showed that the African varanid species Varanus exanthematicus has heightened resistance to snake venoms compared to the Australian species V. giganteus , V. komodoensis , and V. mertensi , likely due to increased predation by sympatric venomous snakes on V. exanthematicus . To understand venom resistance among varanid lizards, we analyzed the receptor site targeted by venoms in 27 varanid lizards, including 25 Australian varanids...

Dental developmental and replacement patterns in extinct amniotes have attracted a lot of attention. Notable among these are Paleozoic predatory synapsids, but also Mesozoic theropod dinosaurs, well known for having true ziphodonty, strongly serrated carinae with dentine cores within an enamel cap. The Komodo dragon, Varanus komodoensis, is the only extant terrestrial vertebrate to exhibit true ziphodonty, making it an ideal model organism for gaining new insights into the life history and feeding behaviours of theropod dinosaurs and early synapsids...

Reptiles exhibit a variety of modes of sex determination, including both temperature-dependent and genetic mechanisms. Among those species with genetic sex determination, sex chromosomes of varying heterogamety (XX/XY and ZZ/ZW) have been observed with different degrees of differentiation. Karyotype studies have demonstrated that Gila monsters (Heloderma suspectum) have ZZ/ZW sex determination and this system is likely homologous to the ZZ/ZW system in the Komodo dragon (Varanus komodoensis), but little else is known about their sex chromosomes...

Since the Komodo dragon has been included on The International Union for Conservation of Nature (IUCN) Red List of Threatened Species, it is crucial to know in detail its biology as there is a limited availability of research material on these animals-mainly those who died in zoos or whose remains were found in the wild. Anatomy is essential for understanding physiology, identification of diseases, adaptations in the environment, and behavior. In this dissection study, the relationship of individual anatomical structures was analyzed, the anatomy of the active and passive movement system of the thoracic limb was described, photographs were taken, and a radiographic examination was conducted...

Modifications to UV irradiance for indoor housed herpetofauna can affect behavior and physiology. Low ultraviolet B (UVB) irradiance can result in vitamin D3 deficiency resulting in calcium metabolism disorders including metabolic bone disease and immune suppression. High UVB can result in skin and eye issues, which can be severe enough to cause shock and death. Using tools available for the assessment of UV light, including Ferguson zones and the UV working tool designed by the British and Irish Association of Zoos and Aquaria, we redesigned lighting in our indoor komodo dragon (Varanus komodoensis) habitat to better suit the UV requirements of this species, while studying changes in behavior and physiology...

Reptiles exhibit a variety of modes of sex determination, including both temperature-dependent and genetic mechanisms. Among those species with genetic sex determination, sex chromosomes of varying heterogamety (XX/XY and ZZ/ZW) have been observed with different degrees of differentiation. Karyotype studies have demonstrated that Gila monsters ( Heloderma suspectum ) have ZZ/ZW sex determination and this system is likely homologous to the ZZ/ZW system in the Komodo dragon ( Varanus komodoensis ), but little else is known about their sex chromosomes...

The present study aimed to characterize the macrostructure and microstructure of the mandibular teeth of the Komodo dragon ( Varanus komodoensis ) and the methods it uses to obtain food. Examinations were performed using a stereoscopic microscope, autofluorescence method, histological method and computed microtomography. A detailed macro- and micro-structural description of V. komodoensis mandibular teeth were made. The mandibular teeth are laterally flattened along their entire length and the dental crown is hooked caudally...

BACKGROUND: The Komodo dragon (Varanus komodoensis) is the world's largest living lizard and exists in private captivity worldwide. Bites to humans are rare and have been proposed to be both infectious and venomous. CASE REPORT: A 43-year-old zookeeper was bitten on the leg by a Komodo dragon and suffered local tissue damage with no excessive bleeding or systemic symptoms to suggest envenomation. No specific therapy was administered other than local wound irrigation...

Postoccupancy evaluation (POE) was used to assess newly constructed zoo exhibits from the perspective of three user groups: zoo staff, zoo visitors, and the animals. Staff represents a generally understudied user group in zoo-based POEs. We asked staff to rate the animals' space, the visitors' space, and the staff's space at previous and new exhibits. We also compared zoo visitors' ratings of the animals' behavior and environments, overall exhibit impressions, and the time visitors spent viewing previous and new exhibits...

Population and conservation genetics studies have greatly benefited from the development of new techniques and bioinformatic tools associated with next-generation sequencing. Analysis of extensive datasets from whole-genome sequencing of even a few individuals allows the detection of patterns of fine-scale population structure and detailed reconstruction of demographic dynamics through time. In this study, we investigated the population structure, genomic diversity and demographic history of the Komodo dragon (Varanus komodoensis), the World's largest lizard, by sequencing the whole genomes of 24 individuals from the five main Indonesian islands comprising the entire range of the species...

We performed a meta-analysis of the newly assembled Komodo dragon (Varanus komodoensis) genome to characterize the major histocompatibility complex (MHC) of the species. The MHC gene clusters of the Komodo dragon are gene dense, complex, and contain counterparts of many genes of the human MHC. Our analysis identified 20 contigs encompassing ~ 6.9 Mbp of sequence with 223 annotated genes of which many are predicted orthologs to the genes of the human MHC. These MHC contigs range in size from 13.2 kb to 21...

This study aimed to describe the anatomic features of the normal head of the Komodo dragon ( Varanus komodoensis ) identified by computed tomography. CT images were obtained in two dragons using a helical CT scanner. All sections were displayed with a bone and soft tissue windows setting. Head reconstructed, and maximum intensity projection images were obtained to enhance bony structures. After CT imaging, the images were compared with other studies and reptile anatomy textbooks to facilitate the interpretation of the CT images...

Antagonistic coevolutionary relationships provide intense selection pressure which drive changes in the genotype. Predator-prey interactions have caused some venomous snakes and their predators/prey to evolve α-neurotoxin resistance through changes at the orthosteric site of nicotinic acetylcholine receptors. The presence of negatively charged amino acids at orthosteric site positions 191 and 195 is the ancestral state. These negatively charged amino acids have exerted a selection pressure for snake venom α-neurotoxins to evolve with strong positive charges on their molecular surface, with the opposite-charge attraction facilitating the binding by the neurotoxins...

Hybridization between species occurs more frequently in vertebrates than traditionally thought but distinguishing ancient hybridization from other phenomena that generate similar evolutionary patterns remains challenging. Here, we used a comprehensive workflow to discover evidence of ancient hybridization between the Komodo dragon (Varanus komodoensis) from Indonesia and a common ancestor of an Australian group of monitor lizards known colloquially as sand monitors. Our data comprises >300 nuclear loci, mitochondrial genomes, phenotypic data, fossil and contemporary records, and past/present climatic data...

Introduction. The rise of carbapenem-resistant enterobacteriaceae (CRE) is a growing crisis that requires development of novel therapeutics. Hypothesis. To this end, cationic antimicrobial peptides (CAMPs) represent a possible source of new potential therapeutics to treat difficult pathogens such as carbapenem-resistant Klebsiella pneumoniae (CRKP), which has gained resistance to many if not all currently approved antibiotics, making treatment difficult. Aim. To examine the anti-CRKP antimicrobial activity of the predicted cathelicidins derived from Varanus komodoensis (Komodo dragon) as well as synthetic antimicrobial peptides that we created...

The Komodo dragon ( Varanus komodoensis ) is an endangered, island-endemic species with a naturally restricted distribution. Despite this, no previous studies have attempted to predict the effects of climate change on this iconic species. We used extensive Komodo dragon monitoring data, climate, and sea-level change projections to build spatially explicit demographic models for the Komodo dragon. These models project the species' future range and abundance under multiple climate change scenarios. We ran over one million model simulations with varying model parameters, enabling us to incorporate uncertainty introduced from three main sources: (a) structure of global climate models, (b) choice of greenhouse gas emission trajectories, and (c) estimates of Komodo dragon demographic parameters...

Organismal interactions drive the accumulation of diversity by influencing species ranges, morphology, and behavior. Interactions vary from agonistic to cooperative and should result in predictable patterns in trait and range evolution. However, despite a conceptual understanding of these processes, they have been difficult to model, particularly on macroevolutionary timescales and across broad geographic spaces. Here, we investigate the influence of biotic interactions on trait evolution and community assembly in monitor lizards (Varanus)...

The infrequency of a total solar eclipse renders the event novel to those animals that experience its effects and, consequently, may induce anomalous behavioral responses. However, historical information on the responses of animals to eclipses is scant and often conflicting. In this study, we qualitatively document the responses of 17 vertebrate taxa (including mammals, birds, and reptiles) to the 2017 total solar eclipse as it passed over Riverbanks Zoo and Garden in Columbia, South Carolina. In the days leading up to the eclipse, several focal teams, each consisting of researchers, animal keepers, and student/zoo volunteers conducted baseline observations using a combination of continuous ad libitum and scan sampling of each animal during closely matched seasonal conditions...

We describe the histological appearance of the osteoderms (ODs) of Heloderma suspectum and Varanus komodoensis using multiple staining and microscopy techniques to yield information about their morphology and development. Histological analysis showed that the ODs of H. suspectum are composed of three main tissue types, a superficial layer, herein identified as osteodermine, capping a base composed of Sharpey-fibre bone and lamellar bone rich in secondary osteons (Haversian bone tissue). In contrast, ODs in V...

Apex predators can have substantial and complex ecological roles in ecosystems. However, differences in species-specific traits, population densities, and interspecific interactions are likely to determine the strength of apex predators' roles. Here we report complementary studies examining how interactions between predator per capita metabolic rate and population density influenced the biomass, population energy use, and ecological effects of apex predators on their large mammalian prey. We first investigated how large mammal prey resources and field metabolic rates of terrestrial apex predators, comprising large mammals and the Komodo dragon (Varanus komodoensis), influenced their biomass densities and population energy use requirements...