Papers by Wolfgang Wüster
Current biology : CB, Jan 4, 2018
Invasive species are a key factor contributing to the global decline of biodiversity, and underst... more Invasive species are a key factor contributing to the global decline of biodiversity, and understanding the underlying mechanisms is crucial to mitigate detrimental effects [1]. One such mechanism is the introduction of invasive species with defensive strategies, such as novel toxins, that can disrupt native predator communities [2]. Disruption of such communities can produce trophic cascades, impacting a diverse array of taxa [2]. Madagascar, a globally significant biodiversity hotspot, has recently experienced the introduction of a toxic bufonid amphibian, the Asian common toad (Duttaphrynus melanostictus) [3]. Since its invasion, the toad population has expanded rapidly, making control efforts problematic and eradication extremely difficult [4]. Previous cases of bufonid introductions, such as the ongoing spread of the cane toad (Rhinella marina) in Australia, have resulted in the decimation of many indigenous species [2], prompting fears that Madagascar may be similarly impacted...
Proceedings of the National Academy of Sciences, 2015
Significance Convergence has strong bearing on the fundamental debate about whether evolution is ... more Significance Convergence has strong bearing on the fundamental debate about whether evolution is stochastic and unpredictable or subject to constraints. Here we show that, in certain circumstances, evolution can be highly predictable. We demonstrate that several lineages of insects, amphibians, reptiles, and mammals have utilized the same molecular solution, via the process of convergence, to evolve resistance to toxic cardiac glycosides produced defensively by plants and bufonid toads. The repeatability of this process across the animal kingdom demonstrates that evolution can be constrained to proceed along highly predictable pathways at molecular and functional levels. Our study has important implications for conservation biology by providing a predictive framework for assessing the vulnerability of native fauna to the introduction of invasive toxic toads.
Herpetological Journal, 2001
INTRODUCTIONThe last two decades have seen a revival in interest inthe alpha taxonomy of many gro... more INTRODUCTIONThe last two decades have seen a revival in interest inthe alpha taxonomy of many groups of animals. This re-surgent interest can be traced to several factors,including the increasing awareness of the extreme rateof extinction caused by human activities, the develop-ment of new molecular (e.g. Avise, 1994) and numerical(e.g. Thorpe, 1976, 1987) methods for the investigationof species-level systematics, and a widespread shiftfrom process-based species concepts (in particular, thebiological species concept) towards historical con-cepts, such as the evolutionary and phylogeneticspecies concepts (Wiley, 1981; Cracraft, 1989; Frost &Hillis, 1990). In general, the current trend has been to-wards the recognition of clearly distinct taxa as separatespecies rather than subspecies, without undue concernfor often untestable questions of reproductive compat-ibility.During this paradigm shift, it has become apparentthat the use of the biological species concept – whichgroups similar ...
Herpetologica, 1992
Page 1. Herpetologica, 48(1), 1992, 69-85 C) 1992 by The Herpetologists' League, Inc. AS... more Page 1. Herpetologica, 48(1), 1992, 69-85 C) 1992 by The Herpetologists' League, Inc. ASIATIC COBRAS: POPULATION SYSTEMATICS OF THE NAJA NAJA SPECIES COMPLEX (SERPENTES: ELAPIDAE) IN INDIA AND CENTRAL ASIA ...
Scientific Reports
Facultative parthenogenesis (FP) is widespread in the animal kingdom. In vertebrates it was first... more Facultative parthenogenesis (FP) is widespread in the animal kingdom. In vertebrates it was first described in poultry nearly 70 years ago, and since then reports involving other taxa have increased considerably. In the last two decades, numerous reports of FP have emerged in elasmobranch fishes and squamate reptiles (lizards and snakes), including documentation in wild populations of both clades. When considered in concert with recent evidence of reproductive competence, the accumulating data suggest that the significance of FP in vertebrate evolution has been largely underestimated. Several fundamental questions regarding developmental mechanisms, nonetheless, remain unanswered. Specifically, what is the type of automixis that underlies the production of progeny and how does this impact the genomic diversity of the resulting parthenogens? Here, we addressed these questions through the application of next-generation sequencing to investigate a suspected case of parthenogenesis in a...
Journal Information, 2002
Please note that our login procedure has changed to login via email address and password. ... Ple... more Please note that our login procedure has changed to login via email address and password. ... Please register before using the new site for the first time. ... The access procedure for institutional subscribers has not changed. ... Jennifer C. Daltry and Wolfgang Wüster (2002) A NEW ...
Zootaxa, 2021
We assess the availability of four names proposed by Wells & Wellington (1985) for Australian dea... more We assess the availability of four names proposed by Wells & Wellington (1985) for Australian death adders (Acanthophis). In agreement with previous literature, A. hawkei is an available name, whereas A. armstrongi, A. lancasteri, and A. schistos are not described in conformity with the requirements of Articles 13.1.1 or 13.1.2 of the International Code of Zoological Nomenclature and are therefore considered nomina nuda. Consequently, A. cryptamydros Maddock et al., 2015, is confirmed as the valid name for the Kimberley death adder of Western Australia. We comment on the need for greater clarity in the Code, and emphasise that the responsibility for establishing the availability of new nomina rests with their authors, not subsequent researchers.
Toxicology letters, Jan 25, 2017
Saw-scaled vipers (genus Echis) are one of the leading causes of snakebite morbidity and mortalit... more Saw-scaled vipers (genus Echis) are one of the leading causes of snakebite morbidity and mortality in parts of Sub-Saharan Africa, the Middle East, and vast regions of Asia, constituting a public health burden exceeding that of almost any other snake genus globally. Venom-induced consumption coagulopathy, owing to the action of potent procoagulant toxins, is one of the most relevant clinical manifestations of envenomings by Echis spp. Clinical experience and prior studies examining a limited range of venoms and eected antivenoms have demonstrated for some antivenoms an extreme lack of antivenom cross-reactivity between different species of this genus, sometimes resulting in catastrophic treatment failure. This study undertook the most comprehensive testing of Echis venom effects upon the coagulation of human plasma, and also the broadest examination of antivenom potency and cross-reactivity, to-date. 10 Echis species/populations and four antivenoms (two African, two Asian) were stud...
Biological Journal of the Linnean Society, 2021
Self-published taxon descriptions, bereft of a basis of evidence, are a long-standing problem in ... more Self-published taxon descriptions, bereft of a basis of evidence, are a long-standing problem in taxonomy. The problem derives in part from the Principle of Priority in the International Code of Zoological Nomenclature, which forces the use of the oldest available nomen irrespective of scientific merit. This provides a route to 'immortality' for unscrupulous individuals through the mass-naming of taxa without scientific basis, a phenomenon referred to as taxonomic vandalism. Following a flood of unscientific taxon namings, in 2013 a group of concerned herpetologists organized a widely supported, community-based campaign to treat these nomina as lying outside the permanent scientific record, and to ignore and overwrite them as appropriate. Here, we review the impact of these proposals over the past 8 years. We identified 59 instances of unscientific names being set aside and overwritten with science-based names (here termed aspidonyms), and 1087 uses of these aspidonyms, compared to one instance of preference for the overwritten names. This shows that when there is widespread consultation and agreement across affected research communities, setting aside certain provisions of the Code can constitute an effective last resort defence against taxonomic vandalism and enhance the universality and stability of the scientific nomenclature. ADDITIONAL KEYWORDS: aspidonym-International Code of Zoological Nomenclature-nomenclatural stability-nomenclature-taxonomic vandalism-taxonomy-Principle of Priority. 'Erfüllen wir eine Pflicht gegen die Wissenschaft, die H. v. M[otschulsky] zur Befriedigung seiner unbegrenzten Autoreitelkeit und Mihisucht missbraucht, wenn wir gewissenhaft die wenigen Körner der M.'schen Arbeitsspreu sammeln, seine Arten und Gattungen deuten, um dafür von ihm geschmäht zu werden, oder erfüllen wir eine Pflicht gegen uns selbst, wenn wir ihn in seinen Etudes zu seinem Privatvergnügen drucken lassen, was er will und die entomologischen Zeit-und Vereinsschriften rein von seinen Arbeiten halten, weil wir ihren Werth kennen gelernt haben?'
Science, 2021
Convergent evolution provides insights into the selective drivers underlying evolutionary change.... more Convergent evolution provides insights into the selective drivers underlying evolutionary change. Snake venoms, with a direct genetic basis and clearly defined functional phenotype, provide a model system for exploring the repeated evolution of adaptations. While snakes use venom primarily for predation, and venom composition often reflects diet specificity, three lineages of cobras have independently evolved the ability to spit venom at adversaries. Using gene, protein, and functional analyses, we show that the three spitting lineages possess venoms characterized by an up-regulation of phospholipase A 2 (PLA 2) toxins, which potentiate the action of preexisting venom cytotoxins to activate mammalian sensory neurons and cause enhanced pain. These repeated independent changes provide a fascinating example of convergent evolution across multiple phenotypic levels driven by selection for defense.
Convergent evolution provides insights into the selective drivers underlying evolutionary change.... more Convergent evolution provides insights into the selective drivers underlying evolutionary change. Snake venoms, with a direct genetic basis and clearly defined functional phenotype, provide a model system for exploring the repeated evolution of adaptations. While snakes use venom primarily for predation, and venom composition often reflects diet specificity, three lineages of cobras have independently evolved the ability to spit venom at adversaries. Using gene, protein, and functional analyses, we show that the three spitting lineages possess venoms characterized by an up-regulation of phospholipase A 2 (PLA 2 ) toxins, which potentiate the action of preexisting venom cytotoxins to activate mammalian sensory neurons and cause enhanced pain. These repeated independent changes provide a fascinating example of convergent evolution across multiple phenotypic levels driven by selection for defense.
Royal Society Open Science, 2021
Species identification can be challenging for biologists, healthcare practitioners and members of... more Species identification can be challenging for biologists, healthcare practitioners and members of the general public. Snakes are no exception, and the potential medical consequences of venomous snake misidentification can be significant. Here, we collected data on identification of 100 snake species by building a week-long online citizen science challenge which attracted more than 1000 participants from around the world. We show that a large community including both professional herpetologists and skilled avocational snake enthusiasts with the potential to quickly (less than 2 min) and accurately (69-90%; see text) identify snakes is active online around the clock, but that only a small fraction of community members are proficient at identifying snakes to the species level, even when provided with the snake's geographical origin. Nevertheless, participants showed great enthusiasm and engagement, and our study provides evidence that innovative citizen science/crowdsourcing approaches can play significant roles in training and building capacity. Although identification by an expert familiar with the local snake fauna will always be the gold standard, we suggest that healthcare workers, clinicians, epidemiologists and other parties interested in snakebite could become more connected to these communities, and that professional herpetologists and skilled avocational snake enthusiasts could organize ways to help connect medical professionals to crowdsourcing platforms. Involving skilled avocational snake enthusiasts in decision making could build the capacity of healthcare workers to identify snakes more quickly, specifically and accurately, and ultimately improve snakebite treatment data and outcomes.
Journal of Zoology, 2005
Morphological differences between two semi-arboreal, bird-eating island pitvipers, Bothrops insul... more Morphological differences between two semi-arboreal, bird-eating island pitvipers, Bothrops insularis and Gloydius shedaoensis, and their mainland relatives were investigated. Mitochondrial DNA sequence data for two genes show B. insularis to be rooted within B. jararaca. Bothrops insularis has a more anterior heart, a relatively longer tail, a longer head, and shorter fangs than B. jararaca. The greater head length is paralleled in the ecologically similar G. shedaoensis. Increased head size may represent an adaptation to the abundance of larger food items (migratory passerine birds), providing a selective advantage to snakes able to switch to larger prey at an earlier age. Furthermore, B. insularis and G. shedaoensis have converged on similar body sizes from opposite ancestral states. Other characters, including fang length, tail length and size of neonates do not show parallel variation in G. shedaoensis and B. insularis, suggesting that caution is required when interpreting character state shifts coinciding with ecological shifts in a single species only.
Animals use venoms for multiple purposes, most prominently for prey acquisition and self-defense.... more Animals use venoms for multiple purposes, most prominently for prey acquisition and self-defense. In snakes, venom composition often evolves as a result of selection for optimization for local diet. However, whether selection for a defensive function has also played a role in driving the evolution of venom composition has remained largely unstudied. Here, we use an online survey of snakebite victims to test a key prediction of a defensive function, that envenoming should result in the rapid onset of severe pain. From the analysis of 584 snakebite reports, involving 192 species of venomous snake, we find that the vast majority of bites do not result in severe early pain. Phylogenetic comparative analysis shows that where early pain after a bite evolves, it is often lost rapidly. Our results, therefore, do not support the hypothesis that natural selection for antipredator defense played an important role in the origin of venom or front-fanged delivery systems in general, although there may be intriguing exceptions to this rule.
Proceedings of the Royal Society B, 2019
Understanding the origin and maintenance of phenotypic variation, particularly across a continuou... more Understanding the origin and maintenance of phenotypic variation, particularly across a continuous spatial distribution, represents a key challenge in evolutionary biology. For this, animal venoms represent ideal study systems: they are complex, variable, yet easily quantifiable molecular phenotypes with a clear function. Rattlesnakes display tremendous variation in their venom composition, mostly through strongly dichotomous venom strategies, which may even coexist within a single species. Here, through dense, widespread population-level sampling of the Mojave rattlesnake, Crotalus scutulatus, we show that genomic structural variation at multiple loci underlies extreme geographical variation in venom composition, which is maintained despite extensive gene flow. Unexpectedly, neither diet composition nor neutral population structure explain venom variation. Instead, venom divergence is strongly correlated with environmental conditions. Individual toxin genes correlate with distinct environmental factors, suggesting that different selective pressures can act on individual loci independently of their co-expression patterns or genomic proximity. Our results challenge common assumptions about diet composition as the key selective driver of snake venom evolution and emphasize how the interplay between genomic architecture and local scale spatial heterogeneity in selective pressures may facilitate the retention of adaptive functional polymorphisms across a continuous space.
Scientific Reports, 2018
Facultative parthenogenesis (FP) is asexual reproduction in plant and animal species that would o... more Facultative parthenogenesis (FP) is asexual reproduction in plant and animal species that would otherwise reproduce sexually. This process in vertebrates typically results from automictic development (likely terminal fusion) and is phylogenetically widespread. In squamate reptiles and chondrichthyan fishes, FP has been reported to occur in nature and can result in the production of reproductively viable offspring; suggesting that it is of ecological and evolutionary significance. However, terminal fusion automixis is believed to result in near genome-wide reductions in heterozygosity; thus, FP seems likely to affect key phenotypic characters, yet this remains almost completely unstudied. Snake venom is a complex phenotypic character primarily used to subjugate prey and is thus tightly linked to individual fitness. Surprisingly, the composition and function of venom produced by a parthenogenetic pitviper exhibits a high degree of similarity to that of its mother and conspecifics from the same population. Therefore, the apparent loss of allelic diversity caused by FP appears unlikely to have a significant impact on the prey-capturing ability of this snake. Accordingly, the pitviper offspring produced by FP retained complex phenotypic characteristics associated with fitness. This result reinforces the potential ecological and evolutionary importance of FP and questions our understanding of the inheritance of venom-associated genes. Facultative parthenogenesis (FP) has been reported across the animal kingdom, including all major lineages of jawed vertebrates except mammals 1–4. In these lineages, it has been shown that females have the potential to switch from sexual to asexual (FP) reproduction 5,6 and produce consecutive parthenogenetic births 5–11. Furthermore, second generation FP has been observed in both sharks 12 and snakes (Booth W, unpublished data). Progeny resulting from FP suffer from near genome-wide reductions in heterozygosity due to automictic development 13 (Fig. 1) (but see 14 and response 15), and are essentially half-clones of their mother due to the fusion of the second polar body with the egg nucleus. Because FP in vertebrates was originally only observed in captive situations, it was relegated by some authorities to be an outcome of " reproductive error " and consequently of limited evolutionary significance. However, the plethora of recent reports in birds, lizards, snakes, and sharks, its discovery in natural populations, and recent evidence of the reproductive viability of parthenogens, has altered this initial perspective 4,6,13,16–19 ; highlighting the need for focused research into the ecological and evolutionary significance of FP in vertebrates. Published: xx xx xxxx OPEN
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Papers by Wolfgang Wüster