SEARCH · bioRxiv Science

Results for “Zoology”

Search indexed bioRxiv preprints in genomics, neuroscience, cell biology and bioinformatics. Read source abstracts and check manuscript versions; preprints are not peer reviewed.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 163 records · Page 9Linked to original sources

bioRxiv2019

Genetic and morphological variation is associated with differences in cold-water tolerance and geographic expansion among invasive snails (Melanoides tuberculata) in central Texas

Melanoides tuberculata (Thiaridae) is an old-world freshwater snail that is and now circumtropical. After being introduced in the 1960s via the aquarium trade, populations of M. tuberculata are thriving in spring systems of Texas (USA). Field surveys and experimental investigations of temperature tolerance suggest M. tuberculata is stenothermal, and thus range expansions outside of aquatic habitats with water temperatures between 18{degrees} and 32{degrees}C should be unlikely. However, in 2012 snails were detected in natural aquatic habitats with seasonal temperatures below the experimentally determined lethal thermal minimum. To test whether genetic and phenotypic variation might be associated with cold-water tolerance and range expansion, we sequenced the 16S ribosomal rRNA gene and measured qualitative conch morphology of 170 snails collected at 26 sites in three central Texas rivers. We also conducted phylogenetic analyses of M. tuberculata collected globally and in Texas to determine potential source populations and estimate the number of invasion events. Our results show snails detected in variable temperature habitats are genetically divergent and morphologically distinct from snails collected in habitats with stable temperatures. These data are consistent with at least three introduction events into Texas of M. tuberculata sensu lato that are characterized by distinct habitat preferences, physiological tolerances, and/or adaptive behaviors.

zoology↗

bioRxiv2019

Aquaculture potential of Bohai Red and its hybrid with Agropecten irradians concentricus in southern China

Argopecten irradians concentricus (Say), one of four geographic subspecies of the bay scallop, has become the major cultured species in southern China since its introduction in 1995. However, its population has been significantly reduced due to high mortality.Also, poor growth rate has been observed following decades of culture.Therefore, the introduction or creation of new varieties is an urgent need. This study describes the first introduction of the new strain, Bohai Red, from the north to southern China. Hybridization trials were conducted between the recently introduced new strain and the local specie, A. irradians concentricus (Say). The success of hybridization was confirmed by SSR maker.The adult and juvenile Bohai Red cannot tolerate high temperatures compared to A. irradians concentricus (Say), whether in natural waters or under laboratory conditions. Fertilization rate for A. irradians concentricus (Say) x Bohai Red exceeded 80%, and hatching rate was 70%. The hybrids exhibit heterosis in survival rate, growth rate, and high-temperature tolerance, demonstrating substantial potential to replace A. irradians concentricus (Say) in southern China.

zoology↗

bioRxiv2020

Low light levels increase avoidance behaviour of diurnal fish species: Implications for road culverts

Inadequately designed culverts are known to pose hydraulic barriers to fish passage, but they may also be behavioural barriers if they adversely affect light levels within them. To test this, we performed a choice experiment and quantified the amount of time individuals of four Australian fish species spent in darkened and illuminated areas of an experimental swimming fume. Behavioural responses were reflective of the species diel activity patterns; diurnal species preferred illuminated regions, while nocturnal species preferred the darkened region. We then determined a threshold light level of only ~100-200 lux (c.f. midday sunlight ~100,000 lux) was required to overcome the behavioural barrier in ~ 70% of the diurnal fish tested. Placing these threshold values into field context, 100% of culverts sampled recorded inadequate light levels. Attention is required to better understand the impacts of low light levels in culverts on fish passage and to prioritise restoration.

zoology↗

bioRxiv2020

Exploring the potential genetic heterogeneity in the incidence of hoof and leg disorders in Austrian Fleckvieh and Braunvieh cattle

BackgroundGenetic heterogeneity denotes the situation when different genetic architectures underlying diverse populations result in the same phenotype. In this study, we explore the nature of differences in the incidence of the number of hoof and leg disorders between Braunvieh and Fleckvieh cattle in the context of genetic heterogeneity between the breeds. ResultsDespite potentially higher power of testing due to twice as large sample size, none of the SNPs was significantly associated with the number of hoof and leg disorders in Fleckvieh, while 16 SNPs were significant in Braunvieh. The most promising candidate genes in Braunvieh are: CBLB on BTA01, which causes arthritis in rats; CAV2 on BTA04, which in effects mouse skeletal muscles; PTHLH on BTA05, which causes disease phenotypes related to the skeleton in humans, mice and zebrafish; SORCS2 on BTA06, which causes decreased susceptibility to injury in the mouse. Some of the significant SNPs (BTA01, BTA04, BTA05, BTA13, BTA16) reveal allelic heterogeneity - i.e. differences due to different allele frequencies between Fleckvieh and Braunvieh. Some of the significant regions (BTA01, BTA05, BTA13, BTA16) correlate to inter-breed differences in LD structure and may thus represent false-positive heterogeneity. However, positions on BTA06 (SORCS2), BTA14 and BTA24 mark Braunvieh-specific regions. ConclusionsWe hypothesise that the observed genetic heterogeneity of hoof and leg disorders is a by-product of multigenerational differential selection of the breeds - towards dairy production in the case of Braunvieh and towards beef production in the case of Fleckvieh. Based on the current data set it is no possibly to unequivocally confirm/exclude the hypothesis of genetic heterogeneity in the susceptibility to leg disorders between Fleckvieh and Braunvieh because only explore it through associations and not the causal mutations. Rationales against genetic heterogeneity comprise a limited power of detection of true associations as well as differences in the length of LD blocks and in linkage phase between breeds. On the other hand, multigenerational differential selection of the breeds and no systematic differences in LD structure between the breeds favour the heterogeneity hypothesis at some of the significant sites.

zoology↗

bioRxiv2020

Shift of maternal gut microbiome of Tibetan antelope (Pantholops hodgsonii) during the perinatal period

The maternal gut microbiome can influence and be affected by the substantial physiological changes taking place during the perinatal period. However, little information is known about the changes in the maternal gut microbiome during this period. Tibetan antelope (Pantholops hodgsonii) provide a unique system to address this issue because their summer migration cycle is synchronized with the perinatal period. We used 16S rRNA gene sequencing to generate gut microbiome profiles using fecal samples collected from female migratory Tibetan antelope. We then correlated microbiome diversity with fecal hormone metabolite concentrations of glucocorticoids (GCs) and triiodothyronine (T3) extracted from the same fecal samples. The maternal gut microbiome of Tibetan antelope was dominated by Firmicutes and Bacteroidetes. There was a clear separation in gut microbial composition by female reproductive states based on both hierarchical clustering and PCoA analyses. The shift in the maternal gut microbiome likely reflects the metabolic and immune system dynamics during the perinatal period. Overall, the microbiome diversity was higher in the late pregnancy compared to the postpartum period. The negative association between T3 and microbiome diversity may be moderated by the shift of reproductive states since the correlations disappeared when considering each reproductive state separately. Integrating the microbiome dimension, migration pattern and reproduction may have direct conservation implications as by establishing a baseline of the physiological changes during the migration/perinatal period, we can have a better understanding of the impacts of increasing human activities on the Tibetan Plateau on the reproductive health of Tibetan antelope.

zoology↗

bioRxiv2020

Age-Stage, Two-Sex Life Table of the Menochilus sexmaculatus (Coccinellidae: Coleoptera) Feeding on Different Aphid Species

Ladybird beetle, Menochilus sexmaculatus (Fabricius) (Coleoptera: Coccinellidae), is biological control agent that predate the different aphid species. Both adults and larval stage of M. sexmaculatus feed on aphid species. In this experiment Life table and predation data were collected for M. sexmaculatus feed on four different aphid species Lipaphis erysimi, Myzus persicae, Aphis nerii and Diuraphis noxia. This experiment was conducted under laboratory conditions at 25{+/-}2{degrees}C, 60{+/-}5% RH and L14: D10 h. Different numbers of aphid were provided as a pray in petri dish. The pre-adult development duration of M. sexmaculatus was maximum when fed on M. persicae (12.18 d) and minimum on D. noxia (10.64 d). Similarly, male and female duration was maximum on M. persicae (26.7 d), minimum on L. erysimi (23.67 d) in male and in female maximum on D. noxia (28.00 d), minimum on A. nerii (24.33 d). Net reproductive rate (Ro) range from 117.9 on L. erysimi to 99.55 on M. persicae and intrinsic rate of increase (r) range was 0.21197 d-1 on A. nerii to 0.021559 d-1 on D. noxia. The finite rate of increase ({lambda}) range was 1.240592 d-1 on D. noxia to 1.204918 d-1 on M. persicae, the mean of generation (T) range was 24.68 d-1 on M. persicae to 22.476 d-1 on A. nerii, similarly, the gross reproductive rate (GRR) range was 172.2 d-1 on D. noxia to 115.02 d-1 on M. persicae and Fecundity (F) eggs per female range was 316.8 on D. noxia to 199.1 on M. persicae. In present Study, age-stage two-sex life table gives complete understanding of predator biological aspects against different aphid species. This study will help us to improve mass rearing and use of M. sexmaculatus in biological control of aphids.

zoology↗

bioRxiv2020

Feral pigeon populations: their gene pool and links with local domestic breeds

Columba livia is a wild bird whose domestication has led to a large number of pigeon breeds. The occasional loss or straying of domestic birds determined the origin of feral pigeons, which are now widespread all around the world. In this study, we assumed that the main contribution to feral populations is provided by domestic breeds reared in the same areas. We tested this hypothesis by analysing the variability of 12 microsatellite loci in nine Italian feral populations sampled in areas with different intensities of breeding and selecting domestic breeds. We included in the analysis samples belonging to domestic lineages commonly bred in Italy The pattern of geographic differentiation of feral populations turned out to be rather complex and only partially explained by the geographic distance between populations. This pattern can be understood only when the domestic breeds were included in the analysis. In particular, feral populations located in regions with a long-lasting tradition of pigeon breeding showed a high level of admixture with domestic breeds, in particular with Racing Homer and Piacentino. Ferals from Bolzano, Venice and Sassari were characterized by unique genetic components, almost all of which are not shared by other feral populations and by the considered domestic breeds. Our results further emphasize the complex origin of feral populations which can be properly investigated only by considering the pool of domestic pigeons bred in the considered area and their past and present distribution.View Full Text

zoology↗

bioRxiv2020

Tick-Borne bacterial and protozoan animal pathogens shape the native microbiome within Hyalomma anatolicum anatolicum and Rhipicephalus microplus tick vectors

BackgroundTicks vector a variety of bacterial, viral, and protozoan pathogens of public and animal health significance. Ticks also harbor a diverse community of microbes linked with their biological processes like hematophagy and hence vector competence. The interactions between bacterial and/or protozoan pathogens and their tick vector microbiome are yet to be investigated. In lieu of this, this study was designed to define the microbial composition of uninfected and infected Hyalomma (H.) anatolicum anatolicum and Rhipicephalus (R.) microplus tick species. Methodology/Principal findingsA total of 320 H. anatolicum and R. microplus were screened for the presence of the protozoan (Theileria sp.), and bacterial (Anaplasma marginale) pathogens by PCR. Subsequently, the microbiome of uninfected and infected individual H. anatolicum and R. microplus were analyzed. The highly conserved V1-V3 region of the 16S rRNA gene was sequenced using the MiSeq Illumina platform. The microbiome of female H. anatolicum anatolicum ticks was dominated by the endosymbiont Candidatus Midichloria mitochondrii (CMM) and Francisella-like endosymbiont (FLE) which were not affected by pathogen infection. Ehrlichia species was detected in A. marginale-infected male H. anatolicum anatolicum (6.2%) as opposed to the Theileria sp.-infected female H. anatolicum anatolicum. Coxiella sp. was also detected in uninfected (2.96%) and A. marginale-infected (4.25%), but not in Theileria sp.-infected R. microplus ticks. Analysis of the eukaryote composition in the respectively ticks also revealed the presence of operational taxonomic units (OTUs) belonging to Plasmodium (P.) falciparum in Theileria sp.-infected H. a. anatolicum and R. microplus ticks, while Hepatozoon americanum detected from Theileria sp.-infected and uninfected H. a. anatolicum. Conclusion and SignificanceThis study establishes the extent of the diversity of microbial community of two important tick species from Pakistan and also revealed the presence of Theileria and A. marginale and additional pathogenic bacteria that could be of public health significance. We hypothesized that infection with either a protozoan or bacterial pathogen will alter the microbial composition within these tick species. Interestingly, we reported the detection of the malarial parasite (P. falciparum) from ticks infected with the protozoan pathogen (Theileria sp.). Further validation experiments are required on endosymbionts and pathogens of ticks to investigate how they could be important in the epidemiology of human and animal pathogens.

zoology↗

bioRxiv2020

Modelling the Putative Ancient Distribution of the Costal Rock Pool Mosquito Aedes togoi

The coastal rock pool mosquito, Aedes togoi, is found in coastal east Asia in climates ranging from subtropical to subarctic. However, a disjunct population in the Pacific Northwest of North America has an ambiguous heritage. Two potential models explain the presence of Ae. togoi in North America: ancient Beringian dispersal or modern anthropogenic introduction. Genetic studies have thus far proved inconclusive. Here we described the putative ancient distribution of Ae. togoi habitat in east Asia and examined the climatic feasibility of a Beringian introduction into North America using modern distribution records and ecological niche modeling of bioclimatic data from the last interglacial period (~120,000 BP), the last glacial maximum (~21,000 BP), and the mid-Holocene (~6000 BP). Our results suggest that suitable climatic conditions existed for Ae. togoi to arrive in North America through natural dispersal as well as to persist there until present times. Furthermore, we find that ancient distributions of suitable Ae. togoi habitat in east Asia may explain the genetic relationships between Ae. togoi populations identified in other studies. These findings indicate the utility of ecological niche modeling as a complementary tool for studying insect phylogeography.

zoology↗

bioRxiv2020

Mechanisms associated with pyrethroid resistance in populations of Aedes aegypti (Diptera: Culicidae) from the Caribbean coast of Colombia

Aedes aegypti is the main vector of dengue, chikungunya, and Zika viruses, which are of great public health importance in Colombia. Aedes control strategies in Colombia rely heavily on the use of organophosphate and pyrethroid insecticides, providing constant selection pressure and the emergence of resistant populations. In recent years, insecticide use has increased due to the increased incidence of dengue and recent introductions of chikungunya and Zika. In the present study, pyrethroid resistance was studied across six populations of A. aegypti from the Caribbean coast of Colombia. Susceptibility to {lambda}-cyhalothrin, deltamethrin, and permethrin was assessed, and resistance intensity was determined. Activity levels of enzymes associated with resistance were measured, and the frequencies of three kdr alleles (V1016I, F1534C, V410L) were calculated. Results showed variations in pyrethroid susceptibility across A. aegypti populations and altered enzyme activity levels were detected. The kdr alleles were detected in all populations, with high variations in frequencies: V1016I (frequency ranging from 0.15-0.70), F1534C (range 0.94-1.00), and V410L (range 0.05-0.72). In assays of phenotyped individuals, associations were observed between the presence of V1016I, F1534C, and V410L alleles and resistance to the evaluated pyrethroids, as well as between the VI1016/CC1534/VL410 tri-locus genotype and {lambda}-cyhalothrin and permethrin resistance. The results of the present study contribute to the knowledge of the mechanisms underlying the resistance to key pyrethroids used to control A. aegypti along the Caribbean coast of Colombia.

zoology↗

bioRxiv2020

Can Intestinal Absorption of Dietary Protein Be Improved Through Early Exposure to Plant-Based Diet?

Nutritional Programming (NP) has been studied as a means of mitigating the negative effects of dietary plant protein (PP), but the optimal timing and mechanism behind NP are still unknown. The objectives of this study were: 1) To determine whether zebrafish (Danio rerio) can be programmed to soybean meal (SBM) through early feeding and broodstock exposure to improve SBM utilization; 2) To determine if NP in zebrafish affects expression of genes associated with intestinal nutrient uptake; 3) To determine if early stage NP and/or broodstock affects gene expression associated with intestinal inflammation or any morphological changes in the intestinal tract that might improve dietary SBM utilization. Two broodstocks were used to form the six experimental groups. One broodstock group received fishmeal (FM) diet (FMBS), while the other was fed ("programmed with") SBM diet (PPBS). The first ((+) Control) and the second group ((-) Control) received FM and SBM diet for the entire study, respectively, and were progeny of FMBS. The last four groups consisted of a non-programmed (FMBS-X-PP and PPBS-X-PP) and a programmed group (FMBS-NP-PP and PPBS-NP-PP) from each of the broodstocks. The programming occurred through feeding with SBM diet during 13-23 dph. The non-control groups underwent a PP-Challenge, receiving SBM diet during 36-60 dph. During the PP-Challenge, both PPBS groups experienced significantly lower weight gains than the (+) Control group. NP in early life stages significantly increased the expression of PepT1 in PPBS-NP-PP, compared to PPBS-X-PP. NP also tended to increase the expression of fabp2 in the programmed vs. non-programmed groups of both broodstocks. The highest distal villus length-to-width ratio was observed in the dual-programmed group, suggesting an increase in surface area for nutrient absorption within the intestine. The results of this study suggest that NP during early life stages may increase intestinal absorption of nutrients from PP-based feeds.

zoology↗

bioRxiv2020

New distribution records and range extensions of mosquitoes in British Columbia and the Yukon Territory

We report the first records of Aedes euedes Howard, Dyar, and Knab, and Coquillettidia perturbans (Walker) from Canadas Yukon Territory, and the first record of Ae. decticus Howard, Dyar, and Knab from British Columbia. We also report range extensions in northern BC for the western treehole mosquito, Aedes sierrensis (Ludlow), the common house mosquito, Culex pipiens L., and the cool weather mosquito Culiseta incidens (Thomson).

zoology↗

bioRxiv2020

Identifying Priority Landscapes for Conservation of Snow Leopards in Pakistan

Pakistans total estimated snow leopard habitat is about 80,000 km2 of which about half is considered prime. However, this preliminary demarcation was not always in close agreement with the actual distribution--the discrepancy may be huge at the local and regional level. Recent technological developments like camera trapping and molecular genetics allow for collecting reliable presence records that could be used to construct realistic species distribution based on empirical data and advanced mathematical approaches like MaxEnt. Current study followed this approach to construct accurate distribution of the species in Pakistan. Moreover, movement corridors, among different landscapes, were also identified through the circuit theory. The habitat suitability map, generated from 384 presence points and 28 environmental variables, scored the snow leopards assumed range in Pakistan, from 0 to 0.97. A large shear of previously known range represented low-quality habitat, including areas in lower Chitral, Swat, Astore and Kashmir. Conversely, Khunjerab, Misgar, Chapursan, Qurumber, Broghil, and Central Karakoram represented high-quality habitats. Variables with higher contribution in the MaxEnt model were precipitation of driest month (34%), annual mean temperature (19.5%), mean diurnal range of temperature (9.8%), annual precipitation (9.4%) and river density (9.2). The validation texts suggest a good model fit, and strong prediction power. The connectivity analysis revealed that the population in the Hindukush landscape appears to be more connected with the population in Afghanistan as compared to other populations in Pakistan. Similarly, the Pamir-Karakoram population is better connected with China and Tajikistan, while the Himalayan population was with the population in India. Current study allows for proposing three model landscapes to be considered under GSLEP agenda as regional priority areas, to safeguard safeguard future of the species in the long run. These landsacpes fall in mountain ranges of the Himalaya, Hindu Kush and Karakoram-Pamir, respectively. We also identified gaps in existing protected areas network, and suggest new protected areas in Chitral and Gilgit-Baltistan to protect critical habitats of snow leopard in Pakistan.

zoology↗

bioRxiv2020

Culex erythrothorax: Insecticide Susceptibility and Mosquito Control

Culex erythrothorax Dyar is a West Nile virus (WNV) vector that breeds in wetland habitats with emergent vegetation. Urbanization and recreational activities near wetlands place humans and birds in close proximity to Cx. erythrothorax, increasing the risk of WNV transmission. High adult Cx. erythrothorax abundance peaked in a marsh bordering the San Francisco Bay of California (USA) during the first 3 hours after sunset (5527 {+/-} 4070 mosquitoes / trap night) during which adult mosquito control efforts are likely most effective. These adult mosquitoes were highly sensitive to permethrin, resmethrin, naled, and etofenprox insecticides when tested in a bottle bioassay (LC50 = 0.35, 0.68, 0.71, and 4.1 {micro}g/bottle, respectively). The synergist piperonyl butoxide increased the sensitivity of the mosquitoes to a low concentration of permethrin (0.5 {micro}g/bottle) while also reducing knock down time, but did not have similar effects with a higher permethrin concentration (2.0 {micro}g/bottle). Biochemical enzyme assays measuring bulk mixed-function oxidase, alpha-esterase, or beta-esterase activities in mosquito homogenates were significantly higher in Cx. erythrothorax relative to a strain of Culex pipiens that is sensitive to permethrin. Larvicide that was applied to the site had limited impact on reducing the abundance of adult Cx. erythrothorax. Subsequent removal of emergent vegetation in concert with reduced daily temperature in the environment substantially reduced Cx. erythrothorax abundance. Land managers who have a need to control Cx. erythrothorax in wetlands should consider vegetation removal over applying larvicide, while vector control agencies are likely to successfully control viremic Cx. erythrothorax that enter nearby neighborhoods by applying insecticides that target the adult stage of the mosquito within 3 h of sunset.

zoology↗

bioRxiv2020

Oviposition in flight: the Sabethes albiprivus incredible egg throwing behavior

Mosquitoes display highly variable oviposition strategies and behavior. By using a high-speed camera, we detailly documented for the first time the egg-throwing strategy of the sylvatic yellow fever vector Sabethes albiprivus Theobald in laboratory. An oviposition trap made with sapucaia nut for field collection of tree-hole mosquitoes and obtaining Sa. albiprivus eggs either in the field or in the laboratory colony is described.

zoology↗

bioRxiv2020

Morphological description of the male genital organs of Pontoporia blainvillei (Gervais & d'Orbigny, 1844)

Pontoporia blainvillei or Franciscana is a small cetacean endemic of South Atlantic Ocean and its highlighted as the most endangered species. Despite the necessity to development conservation strategies for Pontoporia blainvillei studies aiming to feature the reproductive biology and morphological characteristics of the genital organs are still scarce. In this context, the aim of this study was describe the morphological aspects of the genital organs of Pontoporia blainvillei. For this purpose, six male specimens of P. blainvillei stranded on the southeast region of Brazil, were used. Initially animals were measured, and the genital organs were collected, dissected and photodocumented. Then, fragments of all collected organs were submitted to microscopic analysis. The male genital organs of P. blainvillei showed similar results described for other cetaceans, such as, topography in abdominal cavity, presence of two testicles with epididymis, fibroelastic penis with sigmoid shape and presence of deferent duct. Moreover, a male uterus non-functional, two vestigial bones that support the penis, one retractor penis muscle and presence of associated muscles that support the entire reproductive apparatus were observed. However, some differences were present, such as, a simple cubic epithelium in the light of the epididymis, a small testicle even in sexually mature animals and absence of prostate, not previously observed in other cetaceans. Therefore, the animals analyzed showed similar features to other cetaceans, however some peculiarities were observed.

zoology↗

bioRxiv2020

Warm periods in repeated cold stresses protect Drosophila against ionoregulatory collapse, chilling injury, and reproductive deficits

In many insects, repeated cold stress, characterized by warm periods that interrupt cold periods, have been found to yield survival benefits over continuous cold stress, but at the cost of reproduction. During cold stress, chill susceptible insects like Drosophila melanogaster suffer from a loss of ion and water balance, and the current model of recovery from chilling posits that re-establishment of ion homeostasis begins upon return to a warm environment, but that it takes minutes to hours for an insect to fully restore homeostasis. Following this ionoregulatory model of chill coma recovery, we predicted that the longer the duration of the warm periods between cold stresses, the better a fly will recover from a subsequent chill coma event and the more likely they will be to survive, but at the cost of fewer offspring. Here, female D. melanogaster were treated to a long continuous cold stress (25 h at 0{degrees}C), or experienced the same total time in the cold with repeated short (15 min), or long (120 min) breaks at 23{degrees}C. We found that warm periods in general improved survival outcomes, and individuals that recovered for more time in between cold periods had significantly lower rates of injury, faster recovery from chill coma, and produced greater, rather than fewer, offspring. These improvements in chill tolerance were associated with mitigation of ionoregulatory collapse, as flies that experienced either short or long warm periods better maintained low hemolymph [K+]. Thus, warm periods that interrupt cold exposures improve cold tolerance and fertility in D. melanogaster females relative to a single sustained cold stress, potentially because this time allows for recovery of ion and water homeostasis.

zoology↗

bioRxiv2020

First study on age and growth of the deep-water Goblin Shark, Mitsukurina owstoni (Jordan, 1898)

Due to poorly mineralizing structures, ageing deep-water elasmobranchs requires nonconventional techniques. The aim of the present study was to develop a reliable ageing technique using the vertebral centrum to provide information about the age and growth parameters in the Goblin Shark, Mitsukurina owstoni (Jordan, 1898). One vertebral centrum from an individual measuring 315.2 cm in total length was analysed. A minimum age of 27 years was estimated. By incorporating priors based on the growth of deep-water sharks and an additional likelihood on L{infty} using data on large male Goblin Sharks, a Bayesian von Bertalanffy growth model was estimated with a male L{infty} of 364 cm total length, weigh 215 kg at L{infty}, grow slowly with a k equal to 0.049, mature at 16.5 years, and live up to 55 years. Our results are essential to provide useful life history information, with the aim of elucidating the cryptic ecology and biology of this deep-water shark.

zoology↗