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1.
Parental care among salamanders is typically provided by females. A rare case of parental care by male salamanders appears to occur in Cryptobranchidae. Yet, paternal behaviors have rarely been reported from natural populations of any Cryptobranchid salamanders, and their adaptive significance is poorly understood. The present study aimed to examine paternal care behaviors in a fully aquatic Japanese giant salamander (Andrias japonicus) in situ. At the beginning of the summer breeding season, large males, called den-masters, occupy burrows along stream banks for breeding and nesting. We videotaped post-breeding behaviors of two den-masters that stayed with the eggs, one in a natural and the other in an artificial nest in natural streams. We identified three behaviors, tail fanning, agitating and egg eating, to be parental care. Tail fanning provides oxygenated water for the eggs. We found that the den-master in the artificial nest, where dissolved oxygen level was lower, displayed tail fanning more frequently. Agitating the eggs with its head and body likely prevents yolk adhesions. The den-masters selectively ate whiter eggs that appeared to be dead or infected with water mold. This behavior, which we termed hygienic filial cannibalism, likely prevents water mold from spreading over healthy eggs. Digital video images relating to this article are available at http://www.momo-p.com/showdetail-e.php?movieid=momo140906aj01a, http://www.momo-p.com/showdetail-e.php?movieid=momo140906aj02a, http://www.momo-p.com/showdetail-e.php?movieid=momo140906aj03a and http://www.momo-p.com/showdetail-e.php?movieid=momo140906aj04a.  相似文献   

2.
Scent marking is critical to intraspecific communication in many mammal species, but little is known regarding its role in communication among different species. We used 4 years of motion-triggered video to document the use of scent marking areas—termed “community scrapes”—by pumas (Puma concolor) (http://www.momo-p.com/showdetail-e.php?movieid=momo160812pc01a) and other carnivore species. We found that gray foxes (Urocyon cinereoargenteus) routinely rubbed their cheeks on puma scrapes (http://www.momo-p.com/showdetail-e.php?movieid=momo160812uc01a), and tested a series of hypotheses to determine its function. We found that gray foxes selected puma scrapes over other objects, and cheek rubbing by foxes was also correlated with how recently a puma had visited the scrape, suggesting that foxes were intent upon accumulating fresh puma scent. Cheek rubbing by foxes was not correlated with their breeding season or with how recently another fox had visited the site. Finally we found a cascading pattern in the occurrence of pumas, coyotes (Canis latrans) and gray foxes at community scrapes, suggesting that gray foxes may use puma scent to deter predation. This is the first published study to find evidence of a subordinate species using the scent of a dominant species to communicate with heterospecifics. The behavioral cascade we found in scent marking patterns also suggests that scent marking could be a mechanism that impacts the distribution and abundance of species. Additional videos pertaining to this article include http://www.momo-p.com/showdetail-e.php?movieid=momo160812uc02a, and http://www.momo-p.com/showdetail-e.php?movieid=momo160812uc03a.  相似文献   

3.
Despite the increasing interest in the use of intromittent male genitalia and coercive mating behaviour in poeciliids, detailed studies of the mating behaviour of most species in this family are lacking. We describe here the mating and aggressive behaviours of Brachyrhaphis olomina, and correlate them with the condition of the female’s ovum and embryos (immature, mature and pregnant). B. olomina performed a wide range of aggressive (sidle spread, tail beating, coordinate) and mating behaviours (approximation, touch, lateral display, touch-lateral display). Some behaviours (e.g. tail beating) are shared with other poeciliids, but two sexual behaviours (touch and lateral display) and one aggressive (coordinate) behaviour may be unique to B. olomina and were not reported in a previous study. Differences in male behaviour when paired with a female with mature ovum (more mating displays, no agonistic movements) suggest that males detect the female’s reproductive condition from some distance. The distinctive nature of mating behaviour in B. olomina highlights the importance of studying different species to have a better understanding of the evolution of mating and aggressive behaviours in poeciliids. Digital video images related to the article are available at http://www.momo-p.com/showdetail-e.php?movieid=momo170720bo01a, http://www.momo-p.com/showdetail-e.php?movieid=momo170720bo02a and http://www.momo-p.com/showdetail-e.php?movieid=momo170720bo03a.  相似文献   

4.
Triatomines (Heteroptera, Reduviidae) are vectors of Trypanosoma cruzi, the etiological agent of Chagas disease in America. These true bugs have traditionally been considered to be blood suckers, although some species have been catalogued as being entomophagous. By using their highly specialized mouthparts, these insects have evolved a stereotyped habit which includes lifting up the proboscis, piercing and sucking, when the occasion arises. Most triatomines bite their sleeping and unaware vertebrate or invertebrate hosts, but they can also search for other targets, guided, in part, by visual and chemical stimuli. In this study, we observed that triatomines apparently visually identify a drop of water in the distance, then taste it with their legs, upon which proboscis extension and sucking ensues. This invariant behavior or fixed action pattern, observed in several triatomine species (Rhodnius prolixus, Triatoma infestans and Panstrongylus geniculatus), was also elicited by a dummy drop of water and guava fruit. We discuss evolutionary and ethological aspects of this innate behavior. Digital video images related to this article are available at http://www.momo-p.com/showdetail-e.php?movieid=momo180314rp01a and http://www.momo-p.com/showdetail-e.php?movieid=momo180314rp03a.  相似文献   

5.
Animals have evolved sophisticated strategies for avoiding predators during the day. These strategies can vary depending on the type of predator and level of threat. Although nocturnal predation is a major cause of animal mortality, antipredator behavior at night is poorly understood. To investigate how diurnal animals adjust their antipredator behavior during these different conditions, peahens (Pavo cristatus) were exposed to a taxidermy raccoon during the daytime and nighttime. During the day, the peahens emitted loud antipredator calls, extended their necks upward, adopted a preflight posture, and approached the predator; at night, the peahens emitted soft hissing calls, remained stationary, piloerected their feathers, and raised their tails. The results demonstrate that birds adopt radically different antipredator behavior depending on whether the threat occurs in the daytime or nighttime. These different tactics could result from limitations in sensory abilities. Videos showing nocturnal and diurnal antipredator behavior of peafowl are available online (http://www.momo-p.com/showdetail-e.php?movieid=momo111110pc01a and http://www.momo-p.com/showdetail-e.php?movieid=momo111110pc02a).  相似文献   

6.
Kudo  Ayumi  Fujii  Takeshi  Ishikawa  Yukio 《Journal of Ethology》2022,40(2):123-131

Among insects, males have evolved the ability to discriminate potential mates to avoid vain mating attempts. In Diptera, courtship and mating behaviors of species that do not discriminate potential mates have rarely been studied. In this study, we investigated copulation attempts of the stalk-eyed fly, Sphyracephala detrahens males, which do not engage in any observable pre-copulatory courtship behavior. We found that sexually mature males attempted to copulate with mature males and immature adults of both sexes, as frequently as with mature females. Successful copulation only occurred with mature females. Immature females rejected mounting males by vibrating their bodies and immature and mature males by incurving their abdomen downward. Comparison of the cuticular hydrocarbon components of individuals of different sexes and maturity levels indicated that the cuticular hydrocarbon profiles were similar regardless of the sex and sexual maturity. Therefore, we suggest that visual or chemical information are of little use for males S. detrahens in discriminating receptive conspecific mates. Since elaborate mate discrimination behaviors lead to additional time and energy costs when discrimination is difficult, S. detrahens may increase reproductive success simply by increasing the number of copulation attempts. Digital video images related to this article are available at http://www.momo-p.com/showdetail-e.php?movieid=momo211123sd01a, http://www.momo-p.com/showdetail-e.php?movieid=momo211123sd02a, http://www.momo-p.com/showdetail-e.php?movieid=momo211123sd03a, and http://www.momo-p.com/showdetail-e.php?movieid=momo211123sd04a.

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7.
Variation in body composition is a popular obsession. The culturally ‘ideal’ body type is light on fat and heavy on muscle but the human population is collectively laying on fat. A new study finds antagonistic effects of two imprinted genes, Grb10 and Dlk1, on body composition in mice. These findings pose the question whether there is an evolutionary conflict between genes of maternal and paternal origin over the optimal proportions of body fat and lean muscle mass.See research article: http://www.biomedcentral.com/1741-7007/12/771  相似文献   

8.
The search for a common developmental genetic mechanism of body segmentation appears to become more difficult, and more interesting, as new segmented organisms are added to the roster. Recent work in this journal by Brena and Akam on segmentation of the geophilomorph centipede Strigamia maritima, an arthropod distantly related to the standard insect models, contains developmental and evolutionary surprises that highlight the importance of a wider sampling of phyla.See research article: http://www.biomedcentral.com/1741-7007/11/112  相似文献   

9.
In the absence of a vaccine or a cure, identification of novel HIV-1 inhibitors remains important. A paper in Retrovirology describes a rationally designed bi-specific protein that irreversibly damages the viral envelope glycoprotein complex via a two-punch mechanism. In contrast to traditional drugs that inhibit essential steps in the viral life cycle at the cell surface or in the infected cells, this inhibitor cripples free virus in the absence of cells.See research article: http://www.retrovirology.com/content/9/1/104  相似文献   

10.
Current interest in proteasome inhibitors for cancer therapy has stimulated considerable research efforts to identify the molecular pathway to their cytotoxicity with a view to identifying the mechanisms of sensitivity and resistance as well as informing the development of new drugs. Zhao and Vuori describe this month in BMC Biology experiments indicating a novel role of the adaptor protein p130Cas in sensitivity to apoptosis induced not only by proteasome inhibitors but also by the unrelated drug doxorubicin.See research article: http://www.biomedcentral.com/1741-7007/9/73  相似文献   

11.
Delving into European prehistory, two recent studies analyze ancient DNA from bison species depicted by our ancestors on the walls of their caves. The DNA tells a story of migrations driven by climate change but leaves some mystery clouding the genetic descent and climate preference of the still-extant wisent, otherwise known as the European bison.See research articles: https://bmcbiol.biomedcentral.com/articles/10.1186/s12915-016-0317-7 http://www.nature.com/articles/ncomms13158  相似文献   

12.
Genome-based phylogeny plays a central role in the future taxonomy and phylogenetics of Bacteria and Archaea by replacing 16S rRNA gene phylogeny. The concatenated core gene alignments are frequently used for such a purpose. The bacterial core genes are defined as single-copy, homologous genes that are present in most of the known bacterial species. There have been several studies describing such a gene set, but the number of species considered was rather small. Here we present the up-to-date bacterial core gene set, named UBCG, and software suites to accommodate necessary steps to generate and evaluate phylogenetic trees. The method was successfully used to infer phylogenomic relationship of Escherichia and related taxa and can be used for the set of genomes at any taxonomic ranks of Bacteria. The UBCG pipeline and file viewer are freely available at https://www.ezbiocloud.net/tools/ubcg and https://www.ezbiocloud.net/tools/ubcg_viewer, respectively.  相似文献   

13.
Using Japanese literature, we created a consolidated list of host records of butterflies in Japan. The list used the host records described in eight major illustrated reference books, two checklists, and 14 other pieces of literature. The presence of larvae on plants, the observation of larvae eating plants or insects in the field were considered as host records. We collected all species recorded in Japan. Scientific, family, and Japanese names of butterflies were consolidated using the BINRAN database (http://binran.lepimages.jp/). Scientific and Japanese names of host plants were based on the YList database (http://ylist.info/). If scientific names of host plants were not found in YList, we used scientific names based on The Plant List (http://www.theplantlist.org/). Family names of host plants were based on the Catalogue of Life database (http://www.catalogueoflife.org/). Scientific, family, and Japanese names of host insects were based on the MOKUROKU database (http://konchudb.agr.agr.kyushu-u.ac.jp/mokuroku/) for Hymenoptera and the catalogue of the Paraneoptera of Japan published by the Entomological Society of Japan for Hemiptera. We also provided the references of each host record and the original names described in the referred literature. Two datasets, HostDB and ReferenceDB, were created to include 3600 records of butterfly larval hosts in Japan, along with scientific and Japanese names of each species and a literature list. These datasets will be useful for basic and applied biological studies of butterflies. Data files are stored in the Ecological Research Data Archives (http://db.cger.nies.go.jp/JaLTER/ER_DataPapers/) and available from http://hostbj.lepumus.net/. These datasets are published under the Creative Commons License Attribution-ShareAlike 4.0 (CC BY-SA, https://creativecommons.org/licenses/by-sa/4.0/).  相似文献   

14.
Hsp90 reveals phenotypic variation in the laboratory, but is Hsp90 depletion important in the wild? Recent work from Chen and Wagner in BMC Evolutionary Biology has discovered a naturally occurring Drosophila allele that downregulates Hsp90, creating sensitivity to cryptic genetic variation. Laboratory studies suggest that the exact magnitude of Hsp90 downregulation is important. Extreme Hsp90 depletion might reactivate transposable elements and/or induce aneuploidy, in addition to revealing cryptic genetic variation.See research article http://wwww.biomedcentral.com/1471-2148/12/25  相似文献   

15.
16.
Many biological studies are carried out on large populations of cells, often in order to obtain enough material to make measurements. However, we now know that noise is endemic in biological systems and this results in cell-to-cell variability in what appears to be a population of identical cells. Although often neglected, this noise can have a dramatic effect on system responses to environmental cues with significant and often counter-intuitive biological outcomes. A recent study in BMC Systems Biology provides an example of this, documenting a bimodal distribution of activated extracellular signal-regulated kinase in a population of cells exposed to epidermal growth factor and demonstrating that the observed bimodality of the response is induced purely by noise.See research article: http://www.biomedcentral.com/1752-0509/6/109  相似文献   

17.
Identifying the biological pathways that are related to various clinical phenotypes is an important concern in biomedical research. Based on estimated expression levels and/or p values, overrepresentation analysis (ORA) methods provide rankings of pathways, but they are tainted because pathways overlap. This crosstalk phenomenon has not been rigorously studied and classical ORA does not take into consideration: (1) that crosstalk effects in cases of overlapping pathways can cause incorrect rankings of pathways, (2) that crosstalk effects can cause both excess type I errors and type II errors, (3) that rankings of small pathways are unreliable, and (4) that type I error rates can be inflated due to multiple comparisons of pathways. We develop a Bayesian hierarchical model that addresses these problems, providing sensible estimates and rankings, and reducing error rates. We show, on both real and simulated data, that the results of our method are more accurate than the results produced by the classical overrepresentation analysis, providing a better understanding of the underlying biological phenomena involved in the phenotypes under study. The R code and the binary datasets for implementing the analyses described in this article are available online at: http://www.eng.wayne.edu/page.php?id=6402.  相似文献   

18.

Background

Hepatocellular carcinoma (HCC) is the fifth most common cancer and the third cause of cancer-related deaths, worldwide. It is essential to develop an effective prognostic biomarker and determine the mechanisms underlying HCC invasion and metastasis.

Aims

This study aimed to investigate the expression of Golgi glycoprotein73 (GP73) and Epithelial-mesenchymal transition (EMT) molecules such as E-cadherin and Vimentin in HCC. We also evaluated the prognostic value of GP73 in HCC.

Methods

Immunohistochemistry (IHC) was used to determine the expression of GP73 and EMT molecules in 75 HCC specimens and the corresponding paracarcinomatous liver (PCL) tissues. Spearman’s correlation test was used to analyze the correlation of GP73 and EMT molecules. Clinicopathological features of the HCC patients were also analyzed. Univariate survival analysis was performed by the Kaplan–Meier method and differences among the groups were analyzed by the Log-rank test.

Results

GP73 expression in HCC was higher compared with PCL tissues (χ 2 ?=?73.60, P?<?0.05). EMT molecules were also detected in HCC and PCL tissues. GP73 was negatively correlated with E-cadherin (r?=?? 0.49, P?<?0.05), but positively correlated with Vimentin (r?=?0.46, P?<?0.05) in HCC. GP73 was correlated with the clinicopathological features including Edmondson grade, vascular invasion and TNM stage (P?<?0.05), which was also associated with overall survival (OS) (P?<?0.05).

Conclusions

GP73 was negatively with E-cadherin and positively correlated with Vimentin. It might be associated with aggressive behavior of HCC and had influence on patients’ OS. Further research is needed to determine the potential of GP73.
  相似文献   

19.

Background

Small trials have suggested that fluoxetine may improve neurological recovery from stroke. FOCUS, AFFINITY and EFFECTS are a family of investigator-led, multicentre, parallel group, randomised, placebo-controlled trials which aim to determine whether the routine administration of fluoxetine (20 mg daily) for six months after an acute stroke improves patients’ functional outcome.

Methods/Design

The core protocol for the three trials has been published (Mead et al., Trials 20:369, 2015). The trials include patients aged 18 years and older with a clinical diagnosis of stroke and persisting focal neurological deficits at randomisation 2–15 days after stroke onset. Patients are randomised centrally via each trials’ web-based randomisation system using a common minimisation algorithm. Patients are allocated fluoxetine 20 mg once daily or matching placebo capsules for six months. The primary outcome measure is the modified Rankin scale (mRS) at six months. Secondary outcomes include: living circumstances; the Stroke Impact Scale; EuroQol (EQ5D-5 L); the vitality subscale of the 36-Item Short Form Health Survey (SF36); diagnosis of depression; adherence to medication; serious adverse events including death and recurrent stroke; and resource use at six and 12 months and the mRS at 12 months.

Discussion

Minor variations have been tailored to the national setting in the UK (FOCUS), Australia, New Zealand and Vietnam (AFFINITY) and Sweden (EFFECTS). Each trial is run and funded independently and will report its own results. A prospectively planned individual patient data meta-analysis of all three trials will provide the most precise estimate of the overall effect and establish whether any effects differ between trials or subgroups. This statistical analysis plan describes the core analyses for all three trials and that for the individual patient data meta-analysis. Recruitment and follow-up in the FOCUS trial is expected to be completed by the end of 2018. AFFINITY and EFFECTS are likely to complete follow-up in 2020.

Trial registration

FOCUS: ISRCTN, ISRCTN83290762. Registered on 23 May 2012. EudraCT, 2011-005616-29. Registered on 3 February 2012.AFFINITY: Australian New Zealand Clinical Trials Registry, ACTRN12611000774921. Registered on 22 July 2011.EFFECTS: ISRCTN, ISRCTN13020412. Registered on 19 December 2014. Clinicaltrials.gov, NCT02683213. Registered on 2 February 2016. EudraCT, 2011-006130-16. Registered on 8 August 2014.
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20.
In complex animal vocalizations, such as bird or whale song, a great variety of songs can be produced via rearrangements of a smaller set of 'syllables', known as 'phonological syntax' or 'phonocoding' However, food or alarm calls, which function as referential signals, were previously thought to lack such combinatorial structure. A new study of calls in the banded mongoose Mungos mungo provides the first evidence of phonocoding at the level of single calls. The first portion of the call provides cues to the identity of the caller, and the second part encodes its current activity. This provides the first example known in animals of something akin to the consonants and vowels of human speech.See research article http://www.biomedcentral.com/1741-7007/10/97  相似文献   

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