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1.
Proc Biol Sci ; 291(2016): 20232403, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38351807

RESUMO

By imposing novel selection pressures on both participants, biological invasions can modify evolutionary 'arms races' between hosts and parasites. A spatially replicated cross-infection experiment reveals strong spatial divergence in the ability of lungworms (Rhabdias pseudosphaerocephala) to infect invasive cane toads (Rhinella marina) in Australia. In areas colonized for longer than 20 years, toads are more resistant to infection by local strains of parasites than by allopatric strains. The situation reverses at the invasion front, where super-infective parasites have evolved. Invasion-induced shifts in genetic diversity and selective pressures may explain why hosts gain advantage over parasites in long-colonized areas, whereas parasites gain advantage at the invasion front.


Assuntos
Parasitos , Infecções por Rhabditida , Rhabditoidea , Animais , Humanos , Interações Hospedeiro-Parasita , Infecções por Rhabditida/parasitologia , Bufo marinus , Espécies Introduzidas
2.
J Exp Biol ; 226(24)2023 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-38009047

RESUMO

It is well established that arterial pH decreases with increased temperature in amphibians and reptiles through an elevation of arterial PCO2, but the underlying regulation remains controversial. The alphastat hypothesis ascribes the pH fall to a ventilatory regulation of protein ionisation, but the pH reduction with temperature is lower than predicted by the pKa change of the imidazole group on histidine. We hypothesised that arterial pH decreases at high, but not at low, temperatures when toads (Rhinella marina) and snakes (Python molurus) are exposed to hyperoxia. In toads, hyperoxia caused similar elevations of arterial PCO2 at 20 and 30°C, indicative of a temperature-independent oxygen-mediated drive to breathing, whereas PCO2 was unaffected by hyperoxia in snakes at 25 and 35°C. These findings do not support our hypothesis of an increased oxygen-mediated drive to breathing as body temperature increases.


Assuntos
Boidae , Hiperóxia , Animais , Temperatura , Bufo marinus , Oxigênio/metabolismo , Concentração de Íons de Hidrogênio
3.
J Chem Neuroanat ; 133: 102345, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37778734

RESUMO

Thimet oligopeptides (THOP 1) is a metal-dependent peptidase involved in the metabolism of neuropeptides and the presentation of peptides via MHC-1. It has been shown to play a role in the regulation of protein-protein interactions and the metabolism of intracellular peptides. THOP 1 is associated with important biological processes such as metabolism and neurodegenerative diseases, among others. The objective of this study is to elucidate the distribution of THOP 1 in the Bufo marinus brain. The analysis of THOP 1 amino acid sequences indicates that they have been conserved throughout evolution, with significant homology observed across various phyla. When comparing amphibians with other species, more than 70% identity can be identified. Immunohistochemistry analysis of the toad's brain has demonstrated that the enzyme has a ubiquitous distribution, consistent with previous findings in mammals. THOP 1 can be found in important areas of the brain, such as bulb, thalamic nuclei, striatum, hypothalamus, and among others. Nonetheless, THOP 1 is consistently localized within the nucleus, a pattern also observed in the rat brain. Therefore, based on these results, the toad appears to be an excellent model for studying the general biology of THOP 1, given the substantial homology of this enzyme with mammals and its similarity in distribution within the brain.


Assuntos
Bufo marinus , Metaloendopeptidases , Animais , Ratos , Bufo marinus/metabolismo , Peptídeos/metabolismo , Núcleos Talâmicos/enzimologia , Metaloendopeptidases/metabolismo , Encéfalo/enzimologia
4.
Sci Rep ; 13(1): 9587, 2023 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-37311915

RESUMO

Biological invasions can favour rapid changes in intraspecific competitive mechanisms such as cannibalism by imposing novel evolutionary pressures. For example, cane toad (Rhinella marina) tadpoles are highly cannibalistic on eggs and hatchlings in their invasive range in Australia, but not in their native range in South America. Whether such changes in cannibalism occur in invasive populations of other amphibian species is unknown. To explore this question, we collected wild-laid egg clutches of Japanese common toads (Bufo japonicus) from native and invasive populations in Japan, and conducted laboratory experiments to examine cannibalism responses. Contrary to the Australian system, we found that invasion has been accompanied by reduced cannibalistic tendency of B. japonicus tadpoles. This reduction has occurred despite invasive-range B. japonicus eggs/hatchlings being more vulnerable than native-range B. japonicus eggs/hatchlings to cannibalism by native-range conspecific tadpoles, and to predation by native-range frog tadpoles. Our findings thus support the idea that biological invasions can generate rapid changes in rates of cannibalism, but also show that decreases as well as increases can occur. Future work could investigate the proximate cues and selective forces responsible for this rapid decrease in rates of cannibalism by tadpoles in an invasive B. japonicus population.


Assuntos
Bufo marinus , Canibalismo , Animais , Austrália , Larva , Japão
5.
Evolution ; 77(8): 1744-1755, 2023 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-37279524

RESUMO

Natural populations can show rapid adaptive responses to intense (human-mediated) environmental change. The potential for exploiting rapidly evolved traits for conservation management has been often discussed but rarely implemented. Capitalizing on a well-studied biological invasion, we here explore the idea that rapid phenotypic change in the invaders, their pathogens, and the native biota provide opportunities for managers to control invader abundance and buffer adverse impacts on native wildlife. Intensive studies of the invasion of tropical Australia by cane toads (Rhinella marina) have identified newly evolved vulnerabilities that we could exploit for toad control; and newly evolved resilience of native wildlife that we could exploit for impact reduction. For example, distinctive phenotypes of toads at the expanding range edge enhance dispersal rate but reduce reproductive output, intraspecific competitive ability, and immunocompetence; and the evolution of larval cannibalism creates opportunities not only for species-specific trapping of toad tadpoles, but also could be exploited (when allied to emerging CRISPR-Cas9 techniques) to intensify intraspecific conflict in invasive toads. That is, we could use the invasive species to control their own populations. This case study illustrates the potential of detailed basic research to identify novel approaches for conservation.


Assuntos
Animais Selvagens , Espécies Introduzidas , Animais , Humanos , Bufo marinus/fisiologia , Austrália , Larva , Fenótipo
6.
Philos Trans R Soc Lond B Biol Sci ; 378(1882): 20220122, 2023 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-37305913

RESUMO

Variation in food resources can result in dramatic fluctuations in the body condition of animals dependent on those resources. Decreases in body mass can disrupt patterns of energy allocation and impose stress, thereby altering immune function. In this study, we investigated links between changes in body mass of captive cane toads (Rhinella marina), their circulating white blood cell populations, and their performance in immune assays. Captive toads that lost weight over a three-month period had increased levels of monocytes and heterophils and reduced levels of eosinophils. Basophil and lymphocyte levels were unrelated to changes in mass. Because individuals that lost mass had higher heterophil levels but stable lymphocyte levels, the ratio of these cell types was also higher, partially consistent with a stress response. Phagocytic ability of whole blood was higher in toads that lost mass, owing to increased circulating levels of phagocytic cells. Other measures of immune performance were unrelated to mass change. These results highlight the challenges faced by invasive species as they expand their range into novel environments which may impose substantial seasonal changes in food availability that were not present in the native range. Individuals facing energy restrictions may shift their immune function towards more economical and general avenues of combating pathogens. This article is part of the theme issue 'Amphibian immunity: stress, disease and ecoimmunology'.


Assuntos
Bufo marinus , Imunidade , Leucócitos , Animais , Austrália , Bufo marinus/imunologia
7.
Aust Vet J ; 101(6): 219-224, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36967588

RESUMO

OBJECTIVE: To report the clinical presentations, treatments and outcomes of toad toxicity in domestic cats in Southeastern Queensland, Australia. METHODS: This report describes a retrospective study of 190 cases of cane toad (Rhinella marina) toxicity in cats in south-eastern Queensland, Australia. All cases were presented for veterinary treatment between 2011 and 2020 at four specialist veterinary emergency centres in Southeast Queensland, Australia. Cane toad toxicity was diagnosed based on a history of exposure and clinical signs. RESULTS: Domestic short-hair breeds accounted for 53.6% of the cases. Presentation was seasonal with the highest incidence over the warmer months of the year (November - March). Hypersalivation was described in 96.3% (183/190), tachypnoea in 34.2% (65/190) and altered behaviour in 18.4% (35/190) of cases. Seizures occurred in 1% of cases. Of the 190 cases, 6.3% (12/190) were hospitalised and 0.5% (1/190) were euthanised and overall 99.5% (189/190) survived hospital discharge. CLINICAL SIGNIFICANCE: Cane toad toxicity is relatively common in cats in Southeast Queensland and following buccal lavage the prognosis for recovery was excellent.


Assuntos
Espécies Introduzidas , Animais , Gatos , Queensland/epidemiologia , Bufo marinus , Estudos Retrospectivos , Austrália , Prognóstico
8.
Biol Open ; 12(2)2023 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-36745034

RESUMO

Bacterial assemblages on amphibian skin may play an important role in protecting hosts against infection. In hosts that occur over a range of environments, geographic variation in composition of bacterial assemblages might be due to direct effects of local factors and/or to evolved characteristics of the host. Invasive cane toads (Rhinella marina) are an ideal candidate to evaluate environmental and genetic mechanisms, because toads have evolved major shifts in physiology, morphology, and behavior during their brief history in Australia. We used samples from free-ranging toads to quantify site-level differences in bacterial assemblages and a common-garden experiment to see if those differences disappeared when toads were raised under standardised conditions at one site. The large differences in bacterial communities on toads from different regions were not seen in offspring raised in a common environment. Relaxing bacterial clustering to operational taxonomic units in place of amplicon sequence variants likewise revealed high similarity among bacterial assemblages on toads in the common-garden study, and with free-ranging toads captured nearby. Thus, the marked geographic divergence in bacterial assemblages on wild-caught cane toads across their Australian invasion appears to result primarily from local environmental effects rather than evolved shifts in the host.


Assuntos
Espécies Introduzidas , Animais , Bufo marinus/fisiologia , Austrália , Fenótipo
9.
J Exp Biol ; 226(2)2023 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-36576050

RESUMO

Animals move across a wide range of surface conditions in real-world environments to acquire resources and avoid predation. To effectively navigate a variety of surfaces, animals rely on several mechanisms including intrinsic mechanical responses, spinal-level central pattern generators, and neural commands that require sensory feedback. Muscle spindle Ia afferents play a critical role in providing sensory feedback and informing motor control strategies across legged vertebrate locomotion, which is apparent in cases where this sensory input is compromised. Here, we tested the hypothesis that spindle Ia afferents from hindlimb muscles are important for coordinating forelimb landing behavior in the cane toad. We performed bilateral sciatic nerve reinnervations to ablate the stretch reflex from distal hindlimb muscles while allowing for motor neuron recovery. We found that toads significantly delayed the onset and reduced the activation duration of their elbow extensor muscle following spindle Ia afferent ablation in the hindlimbs. However, reinnervated toads achieved similar elbow extension at touchdown to that of their pre-surgery state. Our results suggest that while toads likely tuned the activation timing of forelimb muscles in response to losing Ia afferent sensation from the hindlimbs they were likely able to employ compensatory strategies that allowed them to continue landing effectively with reduced sensory information during take-off. These findings indicate muscle spindle Ia afferents may contribute to tuning complex movements involving multiple limbs.


Assuntos
Extremidade Inferior , Fusos Musculares , Animais , Fusos Musculares/fisiologia , Membro Anterior/fisiologia , Membro Posterior/fisiologia , Bufo marinus/fisiologia
10.
Parasitol Int ; 92: 102692, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36341837

RESUMO

Rhabdias fuelleborni was described by Travassos (1926), who identified it in the lungs of Rhinella gr. marina (=Bufo marinus) from São Paulo. Later, Kloss (1971) added new information on the morphology and diagnosis of the species and new data on host and localities. However, its taxonomic status remains uncertain, due in particular to the morphological uniformity of Rhabdias spp., while the original description lacks important morphological data. In the present study, we found and reevaluated the type series of R. fuelleborni, as well as examining fresh material obtained from the type host and type locality, using light and scanning electron microscopy and molecular tools. The type series was deposited by Travassos (1926), and according to museum records the type locality is Paraty, Rio de Janeiro, Brazil. Our morphological and molecular analyses reinforce the taxonomic validity of this species, while molecular phylogeny identified a close relationship between R. fuelleborni and Rhabdias sp.4 and Rhabdias sp. from other studies, and from bufonids. Also R. fuelleborni are sister taxa with R. cf. stenocephala from Leptodactylidae from the northeast of Brazil and R. vencesi from Boophis madagascarariensis, Madagascar, according to mitochondrial COI gene.


Assuntos
Rhabdiasoidea , Animais , Filogenia , Brasil , Genes Mitocondriais , Bufo marinus
11.
Syst Parasitol ; 100(2): 183-188, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36515783

RESUMO

The genus Austraplectana Baker, 1981 is a poorly known group of cosmocercoid nematodes. In the present study, a new species of Austraplectana, A. extranes sp. n., was described using both light and scanning electron microscopy, based on specimens collected from the carbine barred frog Mixophyes carbinensis Mahony, Donnellan, Richards & McDonald (Anura: Myobatrachidae) and the cane toad Rhinella marina (Linnaeus) (Anura: Bufonidae) in Australia. Austraplectana extranes sp. n. can be easily distinguished from its congener by the much longer and different morphology of tails in both sexes, the different number and arrangement of caudal papillae, the presence of single precloacal median heart-shaped papilla and large posterior protuberance with cuticular comb-like fringe in male.


Assuntos
Ascaridídios , Nematoides , Feminino , Masculino , Animais , Bufo marinus , Austrália , Especificidade da Espécie
12.
Folia Parasitol (Praha) ; 692022 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-36534006

RESUMO

The genus Maxvachonia Chabaud et Brygoo, 1960 (Ascaridomorpha: Cosmocercidae) is a poorly known group of parasitic nematodes. Species of Maxvachonia are native to Madagascar-Australo-Papuan Region, where they are known to parasitise frogs, snakes and skinks. Unfortunately, most of Maxvachonia species have been inadequately described. In the present study, we report the native species Maxvachonia chabaudi Mawson, 1972 from the intestine of the invasive marine toad Rhinella marina (Linnaeus) in Australia for the first time. We speculate that the marine toads infected with M. chabaudi are likely related to their eating skinks or the similarity in diet/habitat/ecology between the toad and the skinks. The detailed morphology of M. chabaudi was studied using light microscopy and, for the first time, scanning electron microscopy, based on the newly collected specimens. Some characters important for the specific diagnosis of M. chabaudi are reported for the first time, including each lip with distinct inner flanges, the location of vulva varying from anterior to posterior of the oesophageal bulb and the presence of single medio-ventral precloacal papilla. An identification key to the species of Maxvachonia is provided.


Assuntos
Ascaridídios , Nematoides , Animais , Feminino , Bufo marinus/parasitologia , Austrália , Microscopia Eletrônica de Varredura
13.
Mol Ecol ; 31(24): 6440-6456, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36198047

RESUMO

Widespread introduced species can be leveraged to investigate the genetic, ecological and adaptive processes underlying rapid evolution and range expansion, particularly the contributions of genetic diversity to adaptation. Rhinella marina, the cane toad, has been a focus of invasion biology for decades in Australia. However, their introduction history in North America is less clear. Here, we investigated the roles of introduction history and genetic diversity in establishment success of cane toads across their introduced range. We used reduced representation sequencing (ddRAD) to obtain 34,000 SNPs from 247 toads in native (French Guiana, Guyana, Ecuador, Panama, Texas) and introduced (Bermuda, southern Florida, northern Florida, Hawai'i, Puerto Rico) populations. Unlike all other cane toad introductions, we found that Florida populations were more closely related to native Central American lineages (R. horribilis), than to native Southern American lineages (R. marina). Furthermore, we found high levels of diversity and population structure in the native range, corroborating suggestions that R. marina is a species complex. We also found that introduced populations exhibit only slightly lower genetic diversity than native populations. Together with demographic analyses, this indicates founding populations of toads in Florida were larger than previously reported. Lastly, within R. marina, only one of 245 putatively adaptive SNPs showed fixed differences between native and introduced ranges, suggesting that putative selection in these introduced populations is based upon existing genetic variation. Our findings highlight the importance of genetic sequencing in understanding biological introductions and hint at the role of standing genetic variation in range expansion.


Assuntos
Variação Genética , Espécies Introduzidas , Animais , Bufo marinus/genética , Austrália , Variação Genética/genética , Texas
14.
Proc Natl Acad Sci U S A ; 119(41): e2214266119, 2022 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-36179042
15.
Toxicon ; 218: 57-65, 2022 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-36113683

RESUMO

Rhinella marina toad is abundant in Brazil. Its poison contains cardiac glycosides called bufadienolides, which are extensively investigated for their bioactivity. Our aim was to characterize the vasoactivity of Rhinella marina poison (RmP) on the aorta of male Wistar rats. For this, the RmP was first collected and processed to obtain an alcoholic extract. To determine cardiovascular effects of RmP, we performed in vivo tests by administering RmP intravenously in doses of 0.1-0.8 mg/kg. Vascular reactivity was also performed through concentration-response curves to RmP (10 ng/mL to 200 µg/mL) in aortic segments with and without endothelium. RmP induced a concentration-dependent contraction in rat aorta which was partly endothelium-mediated. Nitric oxide contributes with this response in view that incubation with L-NAME increased the contractile response. Additionally, treatment with indomethacin [cyclooxygenase, (COX) inhibitor], nifedipine (L-type voltage-gated calcium channels blocker), and BQ-123 (ETA receptors antagonist) decreased maximum response, and ketanserin (5-HT2 receptors antagonist) decreased pEC50, suggesting active participation of these pathways in the contractile response. On the other hand, apocynin (NADPH oxidase inhibitor) did not alter contractility. Incubation with prazosin (α1-adrenergic receptor antagonist) abolished the contractile response, suggesting that the RmP-induced contraction is dependent on the adrenergic pathway. In the Na+/K+ ATPase protocol, a higher Emax was observed in the RmP experimental group, suggesting that RmP potentiated Na+/K+ATPase hyperpolarizing response. When this extract was injected (i.v.) in vivo, increase in blood pressure and decrease in heart rate were observed. The results were immediate and transitory, and occurred in a dose-dependent manner. Overall, these data suggest that the poison extract of R. marina toad has an important vasoconstrictor action and subsequent vasopressor effects, and its use can be investigated to some cardiovascular disorders.


Assuntos
Bufanolídeos , Venenos , Adenosina Trifosfatases/metabolismo , Adenosina Trifosfatases/farmacologia , Adrenérgicos/farmacologia , Antagonistas Adrenérgicos/farmacologia , Animais , Bufanolídeos/toxicidade , Bufo marinus/metabolismo , Canais de Cálcio , Endotélio Vascular , Hemodinâmica , Indometacina/farmacologia , Ketanserina/farmacologia , Masculino , Metanol/farmacologia , NADPH Oxidases , NG-Nitroarginina Metil Éster , Nifedipino/farmacologia , Óxido Nítrico/metabolismo , Prazosina/farmacologia , Prostaglandina-Endoperóxido Sintases/metabolismo , Ratos , Ratos Wistar , Serotonina/farmacologia , Vasoconstritores
16.
Mol Ecol ; 31(21): 5468-5486, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36056907

RESUMO

Mammal declines across northern Australia are one of the major biodiversity loss events occurring globally. There has been no regional assessment of the implications of these species declines for genomic diversity. To address this, we conducted a species-wide assessment of genomic diversity in the northern quoll (Dasyurus hallucatus), an Endangered marsupial carnivore. We used next generation sequencing methods to genotype 10,191 single nucleotide polymorphisms (SNPs) in 352 individuals from across a 3220-km length of the continent, investigating patterns of population genomic structure and diversity, and identifying loci showing signals of putative selection. We found strong heterogeneity in the distribution of genomic diversity across the continent, characterized by (i) biogeographical barriers driving hierarchical population structure through long-term isolation, and (ii) severe reductions in diversity resulting from population declines, exacerbated by the spread of introduced toxic cane toads (Rhinella marina). These results warn of a large ongoing loss of genomic diversity and associated adaptive capacity as mammals decline across northern Australia. Encouragingly, populations of the northern quoll established on toad-free islands by translocations appear to have maintained most of the initial genomic diversity after 16 years. By mapping patterns of genomic diversity within and among populations, and investigating these patterns in the context of population declines, we can provide conservation managers with data critical to informed decision-making. This includes the identification of populations that are candidates for genetic management, the importance of remnant island and insurance/translocated populations for the conservation of genetic diversity, and the characterization of putative evolutionarily significant units.


Assuntos
Marsupiais , Metagenômica , Animais , Bufo marinus/genética , Comportamento Predatório , Marsupiais/genética , Austrália/epidemiologia
17.
Mol Ecol ; 31(19): 4949-4961, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35894800

RESUMO

Gene expression levels are key molecular phenotypes at the interplay between genotype and environment. Mounting evidence suggests that short-term changes in environmental conditions, such as those encountered in captivity, can substantially affect gene expression levels. Yet, the exact magnitude of this effect, how general it is, and whether it results in parallel changes across populations are not well understood. Here, we take advantage of the well-studied cane toad, Rhinella marina, to examine the effect of short-term captivity on brain gene expression levels, and determine whether effects of captivity differ between long-colonized and vanguard populations of the cane toad's Australian invasion range. We compared the transcriptomes of wild-caught toads immediately assayed with those from toads captured from the same populations but maintained in captivity for seven months. We found large differences in gene expression levels between captive and wild-caught toads from the same population, with an over-representation of processes related to behaviour and the response to stress. Captivity had a much larger effect on both gene expression levels and gene expression variability in toads from vanguard populations compared to toads from long-colonized areas, potentially indicating an increased plasticity in toads at the leading edge of the invasion. Overall, our findings indicate that short-term captivity can induce large and population-specific transcriptomic changes, which has significant implications for studies comparing phenotypic traits of wild-caught organisms from different populations that have been held in captivity.


Assuntos
Poaceae , Transcriptoma , Animais , Austrália , Encéfalo , Bufo marinus/genética , Espécies Introduzidas , Transcriptoma/genética
18.
Sci Rep ; 12(1): 10610, 2022 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-35739164

RESUMO

Wildfires can modify habitat attributes, and those changes may differentially affect males versus females within a species if there is pre-existing niche divergence between the sexes. We used radio-tracking and dissections to study invasive cane toads (Rhinella marina), and performed transect counts on native frogs and cane toads 12 months after extensive fires in forests of eastern Australia. Both toads and native frogs were encountered more frequently in burned sites than in unburned sites. Most microhabitat features were similar between burned versus unburned areas, but fire had differential impacts on the ecology of male versus female toads. In burned areas females were less numerous but were larger, in better body condition, and had consumed more prey (especially, coleopterans and myriapods). The impact of fire on attributes of retreat-sites (e.g., temperature, density of vegetation cover) also differed between the sexes. More generally, intraspecific divergence in ecological traits within a species (as a function of body size as well as sex) may translate into substantial divergences in the impacts of habitat change.


Assuntos
Incêndios , Incêndios Florestais , Animais , Bufo marinus , Ecossistema , Feminino , Espécies Introduzidas , Masculino
19.
Biotechnol J ; 17(9): e2200009, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35652854

RESUMO

Synthetic biology [synbio] applications have the potential to assist in addressing significant global health and environmental challenges. Australian research institutes are investing in formative research to develop synbio technologies capable of meeting these challenges. Alongside the laboratory research, investigating the broader social, institutional, and ethical considerations that synbio presents has been a priority. We conducted targeted qualitative research to uncover the barriers and opportunities for a range of multisectoral stakeholders identified as potential end-users of the science under development. The research provides insights into the research implementation environment for three synthetic biology applications: (1) gene editing cane toads (Rhinella marina) to reduce their environmental impact; (2) engineering bacteriophages to combat antimicrobial resistance in humans; and (3) engineering microbes to improve biomining efficiency in the mining industry. In-depth interviews (N = 23) with government, research and civil society representatives revealed key challenges in the impact pathway for each application. The strongest themes uncovered during interviews related to perceived negative public attitudes towards genetic technologies, a lack of investment in critical research infrastructure, unclear regulatory pathways and the presence of a strong social and environmental imperative underpinning technology development. These findings reveal specific entry points for further engagement with the most immediate end-users of synbio. Separate from research on public attitudes to synbio, the cases highlight the various hurdles to achieving research impact, according to experts who will likely use, approve or invest in these applications in the future. The themes uncovered inform avenues for strengthening engagement and research coordination in Australia and elsewhere.


Assuntos
Bacteriófagos , Biologia Sintética , Animais , Austrália , Bufo marinus , Humanos
20.
PLoS One ; 17(4): e0266708, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35390099

RESUMO

As an invasive organism spreads into a novel environment, it may encounter strong selective pressures to adapt to abiotic and biotic challenges. We examined the effect of water temperature during larval life on rates of survival and growth of the early life-history stages of cane toads (Rhinella marina) from two geographic regions (tropical vs. temperate) in the species' invaded range in eastern Australia. If local adaptation at the southern (cool-climate) invasion front has extended the cold-tolerance of early life-stages, we would expect to see higher viability of southern-population toads under cooler conditions. Our comparisons revealed no such divergence: the effects of water temperature on rates of larval survival and growth, time to metamorphosis, size at metamorphosis and locomotor performance of metamorphs were similar in both sets of populations. In two cases where tropical and temperate-zone populations diverged in responses to temperature, the tropical animals performed better at low to medium temperatures than did conspecifics from cooler regions. Adaptation to low temperatures in the south might be constrained by behavioural shifts (e.g., in reproductive seasonality, spawning-site selection) that allow toads to breed in warmer water even in cool climates, by gene flow from warmer-climate populations, or by phylogenetic conservatism in these traits.


Assuntos
Clima , Espécies Introduzidas , Animais , Bufo marinus/fisiologia , Larva , Filogenia , Água
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