Reproductive Life History Research Articles

Sand tiger shark Carcharias taurus mating season in the northwest Atlantic Ocean inferred from wound healing dynamics

Abstract All sharks and rays reproduce using internal fertilization. This necessitates males and females to be coupled tightly during copulation, and as a result, bite wounds associated with mating occur. The appearance of these bite wounds can be used to gauge the timeframe of mating activity without direct observation of copulation. A wound staging system was developed for the sand tiger shark Carcharias taurus through longitudinal observations of an aquarium-housed female that sustained a full-thickness mating wound, an injury that extends through the epidermis, dermis, and hypodermis, exposing underlying muscle. Four wound stages were established: (1) full-thickness, (2) healing, (3) closure, and (4) scar revision. The female’s stage 1 (full thickness) wound transitioned to stage 2 (healing) 2 weeks post-injury. Stage 3 (wound closure) was observed 3–6 weeks post-injury and stage 4 (scar revision) followed and persisted for the duration of the study, 35 weeks post-injury. The staging system was used to characterize the incidence, severity, and etiology of wounds for in situ sharks aggregating at North Carolina shipwreck sites from digital images contributed to the Spot A Shark USA database. There was a significant association between wound stage and its location or zone on the body as well as season of the year for males and females. Mating wounds on females corroborate a late spring and early summer mating season. The presence of stages 1 and 2 mating wounds on sand tiger sharks in North Carolina suggests the area is used for mating while females with stages 3 and 4 mating wounds provide evidence that the area also serves as gestation habitat for this species. This research highlights minimally invasive methodology that leverages citizen science divers to further characterize the reproductive life history of sand tiger sharks.

Female pumas exhibit behavioral plasticity through partitioning temporal activity at communication hubs based on life stage

AbstractIntraspecific communication among carnivores can be complex and risky, and many solitary carnivores (including pumas; Puma concolor) primarily communicate with potential mates and competitors indirectly via scent marking at communication hubs. We used multiple temporal analyses to understand if pumas of three classes (males, solo females, and females traveling with dependent kittens) varied in their temporal use of communication hubs to reduce risk while gathering information. We hypothesized that males would visit scrapes at typical times (nighttime), but that female behavioral strategies might vary based on whether they had dependent kittens or not. We found that pumas of different classes varied in their temporal patterns: male pumas concentrated their temporal activity at night (which is typical for pumas), solo females also tended to visit during the nighttime (although slightly earlier on average than males), while females with kittens were more active in the daytime. Our findings highlight the importance of communication hubs for intersexual communication in pumas and the flexibility that is inherent in puma behavioral ecology. Females adjusted their temporal behavior and visitation based on their reproductive status and life history stage, likely to assess dominant territorial males while also limiting their risk. Our study provides a mechanistic view of how communication through scent marking allows both long‐term and spatially separated communication to occur and that may allow pumas at different life stages with different risk tolerances to communicate with each other.

Errors in estimating reproductive parameters with macroscopic methods: a case study on the protogynous blacktip grouper Epinephelus fasciatus (Forsskål 1775).

A size-based, histological analysis of the reproductive life history of the blacktip grouper, Epinephelus fasciatus (Forsskål 1775), was conducted in Indonesia to evaluate the error rate associated with macroscopic reproductive analysis. Histological results indicated that E. fasciatus was protogynous with female L50 at 13.4 cm total length (LT) and a size at sexual transition of 22.0 cm LT. The weight-length relationship for the species was W = 0.011 L3.13. Overall sex ratios were significantly female biased, operational sex ratios were significantly male biased, and sex ratios of mature individuals varied predictably with length from female to male dominance as size increased. No significant relationship between length and batch fecundity was found. The population has a spawning period from February to August. Overall, 54.4% of macroscopic evaluations were incorrect compared to histological results. Of the errors, 14.8% were a failure to detect ovotestes, 12.7% were classifying non-gonadal tissue as ovary or testis, 12.2% were misclassifying sex, and 12.7% were misclassifying maturity status. However, the largest source of error (47.7%) was from misclassifying both sex and maturity status. Of these, 92.9% were macroscopically classified as immature females, but were histologically confirmed to be mature males. Compared to histological results, the only accurate macroscopic results were the absence of a sex-based difference in weight-length relationship and spawning seasonality estimated by a gonadosomatic index (February-June). The use of macroscopic methods to estimate reproductive life-history parameters for sex-changing reefes fish may introduce significant inaccuracies and misinterpretations. Of the parameters estimated by histological methods, size at maturity, size-specific sex ratios, and spawning seasonality have the greatest potential to inform local fishery management policy.

The Response of the Gut Physiological Function and Microbiome of a Wild Freshwater Fish (Megalobrama terminalis) to Alterations in Reproductive Behavior.

The fish gut microbiome is well known for its role in degrading nutrients to improve the host's digestion and absorption efficiency. In this study, we focused on the core physiological adaptability during the various reproductive stages of the black Amur bream (Megalobrama terminalis) to explore the interaction mechanisms among the fish host gut mucosal structure, gut enzyme activity, and gut microbial metabolism in the course of the host's reproductive cycle. Our findings showed that M. terminalis exhibited locomotion metabolic type (aids in sporting) in the reproductive stage, and a change to visceral metabolic type (aids in digestion) during non-reproductive and post-reproductive stage phases. The impact of metabolic type selection and energy demand during various reproductive stages on fish nutrition strategy and digestive function was substantial. Our resulted showed that mitochondria in intestinal epithelial cells of reproductive M. terminalis appeared autophagy phenomenon, and the digestive enzyme activities in the intestines of reproductive M. terminalis were lower than those in the non-reproductive and post-reproductive individuals. Moreover, these differences in nutrition strategy have a prominent impact on the gut microbiome of reproductive M. terminalis, compared to non-reproductive and post-reproductive samples. Our findings showed that reproductive females had lower levels of alpha diversity compared to non-reproductive and post-reproductive females. Our results also showed a greater functional variety and an increase in functional genes related to carbohydrate, lipid, amino acid, cofactors, and vitamin metabolic pathways in the NRS and PRS group. It is noteworthy that an enrichment of genes encoding putative enzymes implicated in the metabolism of taurine and hypotaurine was observed in the RS samples. Our findings illustrated that the stability and resilience of the gut bacterial community could be shaped in the wild fish host-microbiome interactions during reproductive life history.

A role of epigenetic mechanisms in regulating female reproductive responses to temperature in a pest beetle.

Many species are threatened by climate change and must rapidly respond to survive in changing environments. Epigenetic modifications, such as DNA methylation, can facilitate plastic responses by regulating gene expression in response to environmental cues. Understanding epigenetic responses is therefore essential for predicting species' ability to rapidly adapt in the context of global environmental change. Here, we investigated the functional significance of different methylation-associated cellular processes on temperature-dependent life history in seed beetles, Callosobruchus maculatus Fabricius 1775 (Coleoptera: Bruchidae). We assessed changes under thermal stress in (1) DNA methyltransferase (Dnmt1 and Dnmt2) expression levels, (2) genome-wide methylation and (3) reproductive performance, with (2) and (3) following treatment with 3-aminobenzamide (3AB) and zebularine (Zeb) over two generations. These drugs are well-documented to alter DNA methylation across the tree of life. We found that Dnmt1 and Dnmt2 were expressed throughout the body in males and females, but were highly expressed in females compared with males and exhibited temperature dependence. However, whole-genome methylation did not significantly vary with temperature, and only marginally or inconclusively with drug treatment. Both 3AB and Zeb led to profound temperature-dependent shifts in female reproductive life history trade-off allocation, often increasing fitness compared with control beetles. Mismatch between magnitude of treatment effects on DNA methylation versus life history effects suggest potential of 3AB and Zeb to alter reproductive trade-offs via changes in DNA repair and recycling processes, rather than or in addition to (subtle) changes in DNA methylation. Together, our results suggest that epigenetic mechanisms relating to Dnmt expression, DNA repair and recycling pathways, and possibly DNA methylation, are strongly implicated in modulating insect life history trade-offs in response to temperature change.

Electrosensory and metabolic responses of weakly electric fish to changing water conductivity.

Weakly electric gymnotiform fishes use self-generated electric organ discharges (EODs) to navigate and communicate. The electrosensory range for these processes is a function of EOD amplitude, determined by the fish's electric organ (EO) output and the electrical conductivity of the surrounding water. Anthropogenic activity, such as deforestation, dams and industrial/agricultural runoff, are known to increase water conductivity in neotropical habitats, likely reducing the electrosensory range of these fish. We investigated whether fish modulate EO output as means of re-expanding electrosensory range after a rapid increase in water conductivity in the pulse-type Brachyhypopomus gauderio and the wave-type Eigenmannia virescens. Furthermore, because EOD production incurs significant metabolic costs, we assessed whether such compensation is associated with an increase in metabolic rate. Following the conductivity increase, B. gauderio increased EOD amplitude by 20.2±4.3% over 6days but with no associated increase in metabolic rate, whereas the EOD amplitude of E. virescens remained constant, accompanied by an unexpected decrease in metabolic rate. Our results suggest that B. gauderio uses a compensation mechanism that requires no metabolic investment, such as impedance matching, or a physiological trade-off wherein energy is diverted from other physiological processes to increase EO output. These divergent responses between species could be the result of differences in reproductive life history or evolutionary adaptations to different aquatic habitats. Continued investigation of electrosensory responses to changing water conditions will be essential for understanding the effects of anthropogenic disturbances on gymnotiforms, and potential physiological mechanisms for adapting to a rapidly changing aquatic environment.

Comparative reproductive ecology of Old and New World Trogons, an order in decline across the world.

Many tropical species show declining populations. The pantropical order Trogoniformes has 76% of its species ranked as declining, reflecting a worldwide problem. Here, we report on the reproductive ecology and life history traits of the declining and near-threatened old world Whitehead's Trogon (Harpactes whiteheadi), the declining new world Collared Trogon (Trogon collaris), and the stable Masked Trogon (T. personatus). We also reviewed the literature on reproductive ecology and life history traits of trogons to assess possible commonalities that might help explain population declines. We found that the declining Whitehead's and Collared Trogons had reasonable nest success (32% and 25%, respectively), while the stable Masked Trogon had poor reproductive success (9%), all contrary to population trends. However, the limited literature data suggested that poor reproductive success may be common among trogons, which may contribute to population declines. Parents fed young at a low rate and had long on-bouts for incubation and nestling warming that reduced activity at the nest, as favored by high nest predation risk over evolutionary time. We found that young fledged from the nest with poorly developed wings, as also favored by high nest predation risk. Evolved nestling periods among trogon species suggests that poor wing development is likely common. Wing development has been shown to affect juvenile survival after leaving the nest. The poor wing development may be an important contributor to population declines that deserves more attention. Evolved life history traits are important to recognize as creating population vulnerabilities in a changing world.

Lifehistory Trade-Offs Influence Women’s Reproductive Strategies

ObjectiveIn a UK national census sample, women from the upper and lower socioeconomic (SES) classes achieve parity in completed family size, despite marked differences in both birth rates and offspring survival rates. We test the hypothesis that women adopt reproductive strategies that manipulate age at first reproduction to achieve this.MethodsWe use a Monte-Carlo modeling approach parameterized with current UK lifehistory data to simulate the reproductive lifehistories of 64,000 individuals from different SES classes, with parameter values at each successive time step drawn from a statistical distribution defined by the census data.ResultsWe show that, if they are to achieve parity with women in the higher socioeconomic classes, women in lower socioeconomic classes must begin reproducing 5.65 years earlier on average than women in the higher SES classes in order to offset the higher class-specific mortality and infertility rates that they experience. The model predicts very closely the observed differences in age at first reproduction in the census data.ConclusionsOpting to delay reproduction in order to purse an education-based professional career may be a high risk strategy that many lower SES women are unwilling and unable to pursue. As a result, reproducing as early as possible may be the best strategy available to them.

Socio-demographic Determinants of Infertility: A Study in Four Selected Provinces of Iran

Objectives: Infertility is one of the reproductive health issues that not only affects infertile couple’s life, but it is a matter of demographic concerns on a vast scale. This study aims to examine the impact of socio-demographic factors on the incidence of infertility. Materials and Methods: We used data from our cross-sectional fertility survey conducted in 2017 in four selected provinces of Iran including Gilan, West Azarbaijan, Sistan and Baluchistan, and Yazd. Using a structured questionnaire, 4088 women of reproductive age were interviewed in the survey for their reproductive life history as well as their socio-demographic and economic condition. Bivariate (chi-square test), and multivariate (Multiple Logistic Regression) analyses are applied to the data to meet the aim of the study. P values less than 0.05 are considered statistically significant where differentials are tested. Results: The prevalence of current infertility according to clinical definition varied from 7.4% in Yazd, 8.6% in West Azerbaijan, 12.4% in Gilan, and 22.3% in Sistan and Baluchistan. Logistic regression analysis revealed a significant association between infertility and the age and age at marriage of women. Controlling for other socio-demographic variables probability of being infertile increases as women get married at an older age. In addition, women who lived in a household with the lowest socio-economic conditions were 80 percent more likely to experience infertility compared to those living in households with the highest socio-economic conditions. Living in Sistan and Baluchistan was also a strong predictor of infertility in the study resulting in a high odds ratio (3.050) compared with women living in Yazd province Conclusions: Women’s age and age at marriage are the most important demographic characteristics in explaining infertility and having a lower socio-economic condition trigger it. Since the age of marriage is increasing in Iran, it may affect primary infertility where childbearing is postponed to the late 30s and early 40s.

Life-history stage determines the diet of ectoparasitic mites on their honey bee hosts

Ectoparasitic mites of the genera Varroa and Tropilaelaps have evolved to exclusively exploit honey bees as food sources during alternating dispersal and reproductive life history stages. Here we show that the primary food source utilized by Varroa destructor depends on the host life history stage. While feeding on adult bees, dispersing V. destructor feed on the abdominal membranes to access to the fat body as reported previously. However, when V. destructor feed on honey bee pupae during their reproductive stage, they primarily consume hemolymph, indicated by wound analysis, preferential transfer of biostains, and a proteomic comparison between parasite and host tissues. Biostaining and proteomic results were paralleled by corresponding findings in Tropilaelaps mercedesae, a mite that only feeds on brood and has a strongly reduced dispersal stage. Metabolomic profiling of V. destructor corroborates differences between the diet of the dispersing adults and reproductive foundresses. The proteome and metabolome differences between reproductive and dispersing V. destructor suggest that the hemolymph diet coincides with amino acid metabolism and protein synthesis in the foundresses while the metabolism of non-reproductive adults is tuned to lipid metabolism. Thus, we demonstrate within-host dietary specialization of ectoparasitic mites that coincides with life history of hosts and parasites.

Salpa genome and developmental transcriptome analyses reveal molecular flexibility enabling reproductive success in a rapidly changing environment

Ocean warming favors pelagic tunicates, such as salps, that exhibit increasingly frequent and rapid population blooms, impacting trophic dynamics and composition and human marine-dependent activities. Salp blooms are a result of their successful reproductive life history, alternating seasonally between asexual and sexual protogynous (i.e. sequential) hermaphroditic stages. While predicting future salp bloom frequency and intensity relies on an understanding of the transitions during the sexual stage from female through parturition and subsequent sex change to male, these transitions have not been explored at the molecular level. Here we report the development of the first complete genome of S. thompsoni and the North Atlantic sister species S. aspera. Genome and comparative analyses reveal an abundance of repeats and G-quadruplex (G4) motifs, a highly stable secondary structure, distributed throughout both salp genomes, a feature shared with other tunicates that perform alternating sexual-asexual reproductive strategies. Transcriptional analyses across sexual reproductive stages for S. thompsoni revealed genes associated with male sex differentiation and spermatogenesis are expressed as early as birth and before parturition, inconsistent with previous descriptions of sequential sexual differentiation in salps. Our findings suggest salp are poised for reproductive success at birth, increasing the potential for bloom formation as ocean temperatures rise.

Host ecology drives frog skin microbiome diversity across ecotone in South-Central North America

Anurans (frogs and toads) are an ecologically diverse group of vertebrate organisms that display a myriad of reproductive modes and life history traits. To persist in such an expansive array of habitats, these organisms have evolved specialized skin that is used for respiration while also protecting against moisture loss, pathogens, and environmental contaminants. Anuran skin is also colonized by communities of symbiotic microorganisms, and these skin microbiota serve critical roles in numerous processes associated with anuran host health and persistence such as pathogen resistance and immunity. However, gaps remain in our understanding of the environmental and evolutionary processes that shape frog skin microbial communities. Here, we combined existing anuran disease data with 16S rRNA skin microbial inventories to elucidate the roles that geographic location, host evolutionary history, host ecology, and pathogen presence play in the microbial community assemblage of five co-distributed frog host species in Oklahoma. These focal species possess distinct ecological preferences: aquatic, semi-aquatic, and arboreal, and our results indicate that host ecology is the primary driver of frog skin microbial community structure. Additionally, compositional differences were observed among select host species based on geographic location, but this was not consistent among all five frog species. We did not find evidence of phylogenetic signal among our samples and results from the Classification and Regression Tree Analysis revealed that the presence of the amphibian pathogen Batrachochytrium dendrobatidis and the severity of infection were not drivers of skin microbiome differences among our focal host species. Results from this comparative study contribute to our growing understanding of the environmental and host-associated drivers of skin microbial community assemblage and represents one of the first studies on landscape-level variation in skin microbial communities among North American frogs.

Breeding and Selecting Corals Resilient to Global Warming.

Selective breeding of resilient organisms is an emerging topic in marine conservation. It can help us predict how species will adapt in the future and how we can help restore struggling populations effectively in the present. Scleractinian corals represent a potential tractable model system given their widescale phenotypic plasticity across fitness-related traits and a reproductive life history based on mass synchronized spawning. Here, I explore the justification for breeding in corals, identify underutilized pathways of acclimation, and highlight avenues for quantitative targeted breeding from the coral host and symbiont perspective. Specifically, the facilitation of enhanced heat tolerance by targeted breeding of plasticity mechanisms is underutilized. Evidence from theoretical genetics identifies potential pitfalls, including inattention to physical and genetic characteristics of the receiving environment. Three criteria for breeding emerge from this synthesis: selection from warm, variable reefs that have survived disturbance. This information will be essential to protect what we have and restore what we can.

Evolution and environment of Caribbean coastal ecosystems

Isolation of the Caribbean Sea from the tropical Eastern Pacific by uplift of the Isthmus of Panama in the late Pliocene was associated with major, taxonomically variable, shifts in Caribbean biotic composition, and extinction, but inferred causes of these biological changes have remained elusive. We addressed this through falsifiable hypotheses about how independently determined historical changes in oceanographic conditions may have been responsible. The most striking environmental change was a sharp decline in upwelling intensity as measured from decreases in intra-annual fluctuations in temperature and consequently in planktonic productivity. We then hypothesized three general categories of biological response based upon observed differences in natural history between the oceans today. These include changes in feeding ecology, life histories, and habitats. As expected, suspension feeders and predators became rarer as upwelling declined. However, predicted increases in benthic productivity by reef corals, and benthic algae were drawn out over more than 1 Myr as seagrass and coral reef habitats proliferated; a shift that was itself driven by declining upwelling. Similar time lags occurred for predicted shifts in reproductive life history characteristics of bivalves, gastropods, and bryozoans. Examination of the spatial variability of biotic change helps to understand the time lags. Many older species characteristic of times before environmental conditions had changed tended to hang on in progressively smaller proportions of locations until they became extinct as expected from metapopulation theory and the concept of extinction debt. Faunal turnover may not occur until a million or more years after the environmental changes ultimately responsible.

Pregnancy and postpartum experiences of women undergoing hemodialysis: a qualitative study.

There are particularities of chronic kidney disease (CKD) in women and their treatment. The biology of women exposes them to greater risk factors for CKD and both pregnancy and the postpartum period place an additional burden on renal health. Pregnancy complications may cause or worsen CKD. To explore the experiences of women with CKD undergoing hemodialysis in relation to their reproductive history. This study consisted of clinical-qualitative design with semi-structured individual interviews and open-ended questions. The sample selection was intentional and according to the theoretical saturation criterion. The data analysis was carried out based on the seven steps of the clinical-qualitative content analysis and validated by Nvivo11. This study was conducted in a public hemodialysis clinic of the Brazilian National Health System. Twelve women undergoing hemodialysis were interviewed. The results from the analysis revealed three categories: 1) Association of pregnancy with CKD; 2) Nebulosity in relation to diagnosis and reproductive history 3) Being a woman undergoing hemodialysis. Our study showed the importance of considering the specificities of CKD in women, suggesting that these issues are important for diagnosis and treatment adherence. Consideration of reproductive life history allows the health of women undergoing hemodialysis to be promoted holistically, including aspects of mental health.

Additional Records of the Elusive Lateritic Plateau Toad <i>Beduka koynayensis</i> (Soman, 1963) (Anura: Bufonidae) from the Surroundings of its Type Locality with an Insight into the Genetic Data

The Koyna Toad, Beduka koynayensis, was described some 50 years ago as Bufo koynayensis. Due to taxonomic changes in the generic position now the species is considered under the recently established genus Beduka. Although the terrestrial toad species are morphologically cryptic and difficult to identify them based on morphological characters alone the members of Beduka are exceptions due to clear body colour patterns and habitat specificity. Even though the species is well studied in terms of reproductive biology, call pattern and life history traits there is a lacuna in the understandings of its range of distribution, morphological and genetic variations due to limited field samples available in the museums and the genetic data availability in the GenBank. Based on the fresh collections around the type locality, here we report morphological variations across the different populations within the species. With the 16S rRNA generated in the study discussions are made on the genetic variations across its range of distribution utilizing the unpublished sequences available in the GenBank.

Divergent effects of climate change on the egg-laying opportunity of species in cold and warm regions.

Climate warming can substantially impact embryonic development and juvenile growth in oviparous species. Estimating the overall impacts of climate warming on oviparous reproduction is difficult because egg-laying events happen throughout the reproductive season. Successful egg laying requires the completion of embryonic development as well as hatching timing conducive to offspring survival and energy accumulation. We propose a new metric-egg-laying opportunity (EO)-to estimate the annual hours during which a clutch of freshly laid eggs yields surviving offspring that store sufficient energy for overwintering. We estimated the EO within the distribution of a model species, Sceloporus undulatus, under recent climate condition and a climate-warming scenario by combining microclimate data, developmental functions, and biophysical models. We predicted that EO will decline as the climate warms at 74.8% of 11,407 sites. Decreasing hatching success and offspring energy accounted for more lost EO hours (72.6% and 72.9%) than the occurrence of offspring heat stress (59.9%). Nesting deeper (at a depth of 12cm) may be a more effective behavioral adjustment for retaining EO than using shadier (50% shade) nests because the former fully mitigated the decline of EO under the considered warming scenario at more sites (66.1%) than the latter (28.3%). We advocate for the use of EO in predicting the impacts of climate warming on oviparous animals because it encapsulates the integrative impacts of climate warming on all stages of reproductive life history.

Antibody development to identify components of IIS and mTOR signaling pathways in lepidopteran species, a set of non-model insects.

Nutritional stress impacts many insect species that have differing reproductive strategies and life histories, yet it is unclear how nutrient-sensing signaling pathways mediate tissue-specific responses to changes in dietary input. In Drosophila melanogaster , insulin/insulin-like growth factor (IIS) and mTOR-mediated signaling within adipocytes regulates oogenesis. To facilitate comparative study of nutrient-sensing pathway activity in the fat body, we developed antibodies to assess IIS (anti-FOXO) and mTOR signaling (anti-TOR) across three nymphalid species (Lepidoptera). By optimizing whole-mount fat body immunostaining, we find FOXO nuclear enrichment in adult adipocytes, like that observed in Drosophila . Additionally, we show a previously uncharacterized TOR localization pattern in the fat body.

The toad less travelled: comparing life histories, ecological niches, and potential habitat of Asian black-spined toads and cane toads

Context Invasive vertebrates have significant negative impacts on biodiversity and agricultural production worldwide. Increased connectivity among countries, through trade and tourism, is escalating the rate of introductions of vertebrate species, particularly herpetofauna, across international borders. In Australia, Asian black-spined toads (ABSTs; Duttaphrynus melanostictus) are one of the species most intercepted at borders. They are considered a biosecurity risk because of the potential for negative environmental impacts, similar to those caused by cane toads (Rhinella marina). Aims We aimed to compare ABSTs with cane toads to investigate potential impacts and distribution of ABSTs in the Australian context. We also aimed to identify knowledge gaps regarding ABST biology and the potential role of cane toads in an ABST invasion in Australia. Methods We undertook a literature review to obtain published data to compare the life history characteristics of ABSTs and cane toads. We also modelled climatic niche overlap and compared suitable habitat for both species in Australia. Key results Our results show ABSTs and cane toads have broadly similar reproductive life histories and feeding niches. In particular, similarities include large clutch sizes, preferred oviposition sites, and diet at tadpole and adult life stages. In Australia, the species share suitable potential habitat, particularly in North Queensland, where the majority of ABST incursions have occurred. The species differ in size, call characteristics, clutch size relative to body size, and egg development rate, although the environment also influences these traits. We identify gaps in our knowledge of ABST spatial ecology, thermal tolerances, water reliance, and habitat. Conclusions ABSTs pose a significant biosecurity threat to Australia. Similarities in life history to cane toads means they may have similar impacts, but may have a more limited distribution in Australia. Invasion of Australia by ABSTs would likely result in interactions with cane toads, but it is not possible to accurately determine the outcomes of those interactions without further investigation. Implications Addressing knowledge gaps and quantitatively determining the potential for competition between ABSTs and cane toads will assist surveillance and response planning for ABST incursions in Australia.

Indigenous Knowledge of Monotreme Oviparity in Tasmania and Mainland Australia: What European Science Refused to Hear

ABSTRACT The most striking feature of monotremes is that they are egg-laying mammals, but this was only accepted by the scientific establishment eight decades after specimens of echidna and platypus were first examined in Europe. Even before the specimens were sent, colonists had been told by Indigenous Australians that the echidna and platypus laid eggs. In this paper I briefly summarise aspects of the significance of monotremes in some mainland Aboriginal cultures, and the attempts by the naturalist George Bennett to discover if platypuses were oviparous. In Tasmania the disruption of Aboriginal culture early in the 19th century meant that there are very few details known of their insights into ecosystems and monotreme biology. Some incidental information was recorded by George Augustus Robinson during his “Friendly Mission”, while what appears to be a previously unremarked presentation at the Royal Society of Van Diemen’s Land in 1849 reveals Aboriginal knowledge of the reproductive behaviour and life history of Tasmanian echidnas not described in the scientific literature until very recently.