PaperPlayer biorxiv zoology

Link to bioRxiv paper:

http://biorxiv.org/cgi/content/short/2020.08.11.246710v1?rss=1

Authors: Turner, T. L.

Abstract:

Sponges (phylum Porifera) are common inhabitants of kelp forest ecosystems in California, but their diversity and ecological importance are poorly characterized in this biome. Here I use freshly collected samples to describe the diversity of the order Scopalinida in California. Though previously unknown in the Eastern Pacific Ocean, four new species are described here: Scopalina nnnn1 sp. nov., S. kkkk sp. nov., S. gggg sp. nov., and S. jjjj sp. nov.. These discoveries illustrate the considerable uncharacterized sponge diversity remaining in California kelp forests, and the utility of SCUBA-based collection to improve our understanding of this diversity.

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Link to bioRxiv paper:

http://biorxiv.org/cgi/content/short/2020.08.11.246058v1?rss=1

Authors: Meijaard, E., Ni'matullah, S., Dennis, R., Hadisiswoyo, P., Sherman, J., O., O., Wich, S. A.

Abstract:

The Tapanuli orangutan ( Pongo tapanuliensis ) is the most threatened great ape species in the world. It is restricted to an area of about 1,000 km 2 of mostly hill forest where fewer than 800 animals survive in three declining subpopulations. Through a historical ecology approach involving analysis of colonial-era and other literature, we demonstrate that historically the Tapanuli orangutan lived in a much larger area, and across a much wider range of habitat types compared to now. Its current range is about 10-20% of the range it had some 150-200 years ago. A combination of historic fragmentation of forest habitats, mostly for small-scale agriculture, and unsustainable hunting likely drove various populations to the south, east and west of the current population to extinction prior to the industrial-scale forest conversion that started in the 1970s. Our findings indicate how sensitive orangutans are to the combined effects of habitat fragmentation and unsustainable mortality or rescue and translocation rates. Saving this species will require prevention of any further fragmentation and any killings or other removal of animals from the remaining population. Without concerted action to achieve this, the remaining populations of Tapanuli orangutan are doomed to become extinct within the foreseeable future.

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Link to bioRxiv paper:

http://biorxiv.org/cgi/content/short/2020.08.11.246009v1?rss=1

Authors: WANG, L., Wang, Q., Cai, H., Wang, H., Huang, Y., Feng, Y., Bai, X., Qin, M., Manguin, S., Gavotte, L., Wu, W., Frutos, R.

Abstract:

Human echinococcosis is present worldwide but it is in China that prevalence is the highest. Western China and in particular the Tibetan plateau is the region where the burden of echinococcosis is the most important. Dogs are a major carrier of echinococcosis and monitoring the presence of Echinococcus worms in dogs is therefore essential for efficiently controlling the disease. Detection kits based on three different technologies, i.e. sandwich ELISA, ELISA and gold immunodiffusion are currently marketed and used in China. The objective of this work was to assess the efficacy of these kits, in particular with respect to sensitivity and specificity. Four fecal antigen detection kits for canine echinococcosis covering the three technologies were obtained from companies and tested in parallel on 220 fecal samples. The results indicate that the performance is lower than expected, in particular in terms of sensitivity. The best results were obtained with the sandwich ELISA technology. The gold immunofiltration yielded the poorest results. In all cases, further development is needed to improve the performance of these kits, which represent a key element for the control of echinococcosis.

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Link to bioRxiv paper:

http://biorxiv.org/cgi/content/short/2020.08.09.243238v1?rss=1

Authors: DuBay, S., Palmer, D. H., Piland, N.

Abstract:

Linnaean taxonomy is a cornerstone of Western biology in which organisms are given a two-part name (a genus and species), creating biological units that help us order and manage our knowledge of the living world. In this system, the names of species themselves take on additional functions, such as describing features of the organism or honoring individuals (known as eponyms). Here, we interrogate how power and authority over the natural world are claimed through Western scientific naming practices to evaluate the legacies of imperialism, dispossession, and exclusion in these practices. We compile and analyze a dataset of all bird species descriptions from 1950 to present, asking: who has access and power to name species, and who is honored in species names? We show that 95% of newly described species are described from the global South, but the majority of species and eponyms are described by authors, and named after individuals, from the global North. We find an increase through time in authors from the global South, which is associated with a rise in eponyms that honor individuals from global South countries. However, this formal inclusion of global South authors has not translated into increases in first authorship (a primary form of credit and authority in Western science). We contextualize these disparities in naming and authorship within broader global structures of access and power put in place through centuries of European and U.S. imperialism, but a historical perspective alone ignores institutional and individual agency and incentives in present-day actions. As we increasingly reflect on the social foundations and impacts of our science, these findings show how research and labor in the global South continue to be disproportionately translated into power and authority in the global North, upholding and re-enacting imperial structures of domination.

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Link to bioRxiv paper:

http://biorxiv.org/cgi/content/short/2020.08.06.240002v1?rss=1

Authors: Blackwell, T., Ford, A. G. P., Ciezarek, A. G., Bradbeer, S. J., Gracida Juarez, C. A., Ngatunga, B. P., Shechonge, A. H., Tamatamah, R., Etherington, G. J., Haerty, W., Di Palma, F., Turner, G. F., Genner, M. J.

Abstract:

Invasive freshwater fish systems are known to readily hybridize with indigenous congeneric species, driving loss of unique and irreplaceable genetic resources. Here we reveal that newly discovered (2013-2016) evolutionarily significant populations of Korogwe tilapia (Oreochromis korogwe) from southern Tanzania are threatened by hybridization with the larger invasive Nile tilapia (Oreochromis niloticus). We use a combination of morphology, microsatellite allele frequencies and whole genome sequences to show that O. korogwe from southern lakes (Nambawala, Rutamba and Mitupa) are distinct from geographically-disjunct populations in northern Tanzania (Zigi River and Mlingano Dam). We also provide genetic evidence of O. korogwe x niloticus hybrids in three lakes and demonstrate heterogeneity in the extent of admixture across the genome. Finally, using the least admixed genomic regions we estimate that the northern and southern O. korogwe populations most plausibly diverged approximately 140,000 years ago, suggesting that the geographical separation of the northern and southern groups is not a result of a recent translocation, and instead these populations represent independent evolutionarily significant units. We conclude that these newly-discovered and phenotypically unique cichlid populations are already threatened by hybridization with an invasive species, and propose that these irreplaceable genetic resources would benefit from conservation interventions.

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Link to bioRxiv paper:

http://biorxiv.org/cgi/content/short/2020.08.07.241141v1?rss=1

Authors: Wrey, M. C., Skaar, J. C., Cates, S. B., Bollman, S. R., Fuentes, C., Blouin, M.

Abstract:

Hatchery reared salmonid fish often have lower fitness than their natural-origin counterparts when spawning in the wild. Although this difference appears to result from rapid adaptation to captivity, it is not known what traits are under selection. We hypothesize that variation in traits that confer a growth rate advantage to some individuals in the novel hatchery environment are under strong selection because survival at sea is correlated with size at release. Here we show that full sibling families of steelhead trout ( Oncorhynchus mykiss ) show substantial variation in propensity to feed at the surface as fry, and that the more surface-oriented families grew faster under hatchery conditions. We hypothesize that surface-oriented fry gain an initial growth advantage that persists through size at release. Because surface orientation is a correlate of generalized boldness, hatcheries may inadvertently select for that phenotype, which could explain the fitness differences observed between hatchery and natural-origin fish in the wild.

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Link to bioRxiv paper:

http://biorxiv.org/cgi/content/short/2020.08.04.236828v1?rss=1

Authors: Tam, J.

Abstract:

Currently, the most effective mosquito repellents employ the use of the chemical N, N-Diethyl-meta-toluamide (DEET), often considered the gold standard of repellents. However, as DEET continues to be widely used, it is beginning to lose efficacy as mosquitoes gradually gain resistance to it. Additionally, DEET only protects the skin that it is applied on, and therefore, it is difficult to achieve 100% repellency for the entire body. As urbanization and climate change continue to increase the threat of widespread mosquito-borne illnesses, new forms of repellents must be developed to combat the possibility of an epidemic. Previous studies indicate that a multitude of insects, including spiders, flies, and mosquitoes, avoid electrostatic fields at sufficiently high voltages. In this study, I evaluate if electrostatic fields can be used as a potential personal repellent against mosquitoes and an alternative to chemical sprays. I found that by charging the surface of a person's body with a high voltage (9800V) but minuscule current, I created a safe and effective method that repels mosquitoes from landing on the skin. This method has similar efficacy to DEET, with near 100% repellency after 20 minutes of charging. It also has the advantage of not needing to be reapplied and provides full-body protection, allowing greater protection to the user than DEET. These results introduce a promising method of repelling mosquitoes, that used together with present-day chemical repellents, can help provide greater protection to malaria-endemic countries.

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Link to bioRxiv paper:

http://biorxiv.org/cgi/content/short/2020.08.04.236539v1?rss=1

Authors: Josek, T., Sperrazza, J., Alleyne, M., Syed, Z.

Abstract:

The black-legged tick, Ixodes scapularis (Ixodida, Ixodidae), is one of the major disease vectors in the United States and due to multiple human impact factors, such as decreasing forest size for land development and climate change, it has expanded its range and established across the United States. Throughout the life cycle, ticks locate hosts for their blood-meal and although the ecologies of this tick and their hosts have been studied in depth, the sensory physiology behind host location largely remains unexplored. Here we report establishing a robust paradigm to isolate and identify odors from the natural milieu for I. scapularis. We performed single sensillum recordings (SSR) from the olfactory sensilla on the tick tarsi, and used the SSR system as biological detector to isolate natural compounds that elicited biological activity. The SSR setup was further tested in tandem with gas chromatography (GC) wherein the ticks olfactory sensillum activity served as a biological detector. The GC-SSR recordings from the wall pore sensilla in the Hallers organ, and further identification of the biologically active deer glad constituents by GC-mass spectrometry (GC-MS) revealed methyl substituted phenols as strong chemostimuli, as compared to ethyl or propyl substitutions. Strongest electrophysiological activity was elicited by meta-cresol followed by para-cresol. Ethyl- and propylphenols with any of the three, ortho, meta or para substitutions, did not induce any neurophysiological activity. Finally, a behavioral analysis in a dual-choice olfactometer of all these phenols at three different doses revealed no significant behavioral response, except for p- cresol at -3 dilution Overall, this study contributes to our understanding of I. scapularis ticks neurophysiology and provides a robust platform to isolate and identify natural attractants and repellents.

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Link to bioRxiv paper:

http://biorxiv.org/cgi/content/short/2020.08.03.234385v1?rss=1

Authors: Graham, Z. A., Palaoro, A. V.

Abstract:

In many species, males possess specialized weaponry that have evolved to confer a benefit during aggressive interactions. Because male weaponry is typically an exaggerated or extreme version of pre-existing body parts, females often possess reduced or weaponry. Although much research has investigated sexual dimorphism in the sizes of such weapons, other weapon components, such as weapon performance or alternative weapon forms can also explain the evolution of weapon sexual dimorphisms. Here, we investigated the allometry and variation of multiple weapon components of hindleg weaponry in the male and female giant mesquite bugs, Thasus necalifornicus. Despite theory predicating greater allocation in male weaponry, we found that females allocated more into the lengths of their hindlegs compared to males. Despite this allocation, males possess relatively wider hindlegs, which likely increase area of muscle mass. Indeed, the squeezing performance of male hindlegs was much greater than that of female hindlegs. Lastly, we also described the allometry and variation in a male weapon component, prominent tibial spines, which likely are used to damage competitors during aggressive interaction. Overall, our findings highlight the intricacies of weapon sexual dimorphism and demonstrate the importance of measuring multiple weapon components and not a single measure.

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Link to bioRxiv paper:

http://biorxiv.org/cgi/content/short/2020.08.02.232728v1?rss=1

Authors: Bhakat, S.

Abstract:

Travassosinema bengalensis n. sp. is described from the hind gut of the spirobolid millipede, Trigoniulus corallinus (Gervais) from West Bengal, India. Females of the new species differ from the only known Indian species, T. travassosi Rao, 1958 by several characters namely tail length, length of oesophagous, size of egg, extension of umbraculum etc. It is very similar to other three species of Travassosinema, T. travassosi, T. thyropygi Hunt, 1996 and T. claudiae Morffe & Hasegawa, 2017 as all of them lack lateral alae and body contraction posterior to vulva. Except T. claudiae, it differs from all other species from millipedes by longest tail length (60% SL) and differs from T. claudiae by shorter oesophagous length and location of vulva. A new method for presentation of morphometric data (in percentage to standard length) in nematode is suggested. On the basis of phylogenetic analysis, it is suggested that umbraculum bearing genera, Indiana, Pulchrocephala should be excluded from the family Travassosinematidae.

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