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1.
Cuttlefish can rapidly alter their appearance by using neurally controlled chromatophore organs. This ability may provide a window into their cognitive capacity. We test whether the changes in body pattern that occur during hunting depend on context. If they do, then it may be possible to use these changes to study cephalopod cognition while the animal is engaged in ecologically relevant tasks. We found consistent individual differences in the tendency of cuttlefish to hunt with the first two arms raised. We also found that cuttlefish usually darken their skin after they seize a prey item. This darkening is observed regardless of the identity of the prey (fish, crab, or shrimp), prey context (buried in sand, in a bare tank, or on top of a rock pile), or the presence of a sudden stimulus. The sudden stimulus was created by presenting an overhead model bird to the cuttlefish. The model induced components of the Deimatic Display, which is a form of antipredator behavior, suggesting that the model was perceived as a potential threat. Passing Cloud displays and the Darkening of the arms were significantly reduced after exposure to the model bird. The effect of a potential predator on body pattern expression during hunting suggests it may be possible to use these changes as a sensitive indicator of ecologically relevant learning. 相似文献
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Magdalena A. Gutowska F. Melzner M. Langenbuch C. Bock G. Claireaux H. O. Pörtner 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》2010,180(3):323-335
Acidification of ocean surface waters by anthropogenic carbon dioxide (CO2) emissions is a currently developing scenario that warrants a broadening of research foci in the study of acid–base physiology.
Recent studies working with environmentally relevant CO2 levels, indicate that some echinoderms and molluscs reduce metabolic rates, soft tissue growth and calcification during hypercapnic
exposure. In contrast to all prior invertebrate species studied so far, growth trials with the cuttlefish Sepia officinalis found no indication of reduced growth or calcification performance during long-term exposure to 0.6 kPa CO2. It is hypothesized that the differing sensitivities to elevated seawater pCO2 could be explained by taxa specific differences in acid–base regulatory capacity. In this study, we examined the acid–base
regulatory ability of S. officinalis in vivo, using a specially modified cannulation technique as well as 31P NMR spectroscopy. During acute exposure to 0.6 kPa CO2, S. officinalis rapidly increased its blood [HCO3
−] to 10.4 mM through active ion-transport processes, and partially compensated the hypercapnia induced respiratory acidosis.
A minor decrease in intracellular pH (pHi) and stable intracellular phosphagen levels indicated efficient pHi regulation. We conclude that S. officinalis is not only an efficient acid–base regulator, but is also able to do so without disturbing metabolic equilibria in characteristic
tissues or compromising aerobic capacities. The cuttlefish did not exhibit acute intolerance to hypercapnia that has been
hypothesized for more active cephalopod species (squid). Even though blood pH (pHe) remained 0.18 pH units below control values,
arterial O2 saturation was not compromised in S. officinalis because of the comparatively lower pH sensitivity of oxygen binding to its blood pigment. This raises questions concerning
the potentially broad range of sensitivity to changes in acid–base status amongst invertebrates, as well as to the underlying
mechanistic origins. Further studies are needed to better characterize the connection between acid–base status and animal
fitness in various marine species. 相似文献
3.
Walter Narchi 《Studies on Neotropical Fauna and Environment》2013,48(4):205-210
Meiocardia agassizii Dall, 1886 is a bivalve that belongs to the family Glos‐sidae, Gray 1847. Described by Dall in 1886, it was dredged by the U.S. Fish Commission off Trinidad from a depth of 210 m. The same species was dredged for the first time in the South Atlantic off the mouth of Rio Doce, Espirito Santo, Brazil. As the specimen was well preserved the study of the soft parts was possible. The mantle, siphons and the organs of the mantle cavity were described and compared to those of Glossus humanus, which belongs to the same family. 相似文献
4.
K. M. Dziegielewska K. Møllgård M. L. Reynolds N. R. Saunders 《Cell and tissue research》1987,248(1):33-41
Summary The human plasma protein, 2HS glycoprotein, has an amino acid composition very similar to that of fetuin, the major protein in fetal calf and lamb serum. Immunohistochemical studies of human fetuses (6–33 weeks gestation) showed that 2HS glycoprotein and fetuin have similar distributions in developing brain and several other tissues, e.g., bone, kidney, gonads, gastrointestinal tract, respiratory and cardiovascular systems. There were notable differences in the liver and thymus in the distribution of the two proteins. Fetuin and 2HS glycoprotein are present in plasma and cerebrospinal fluid of both human and sheep fetuses; their concentrations are reciprocally related: in human plasma and cerebrospinal fluid 2HS glycoprotein concentration is high and fetuin low; the reverse is the case in sheep fetuses.Estimates of the concentration of 2HS glycoprotein in human fetal cerebrospinal fluid and plasma were obtained. It is suggested that 2HS glycoprotein may play a role in developing tissues, especially in the human fetus, similar to that of fetuin in other species. 相似文献
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Pimenta officinalis Lindl. (pimento,myrtle pepper) from early modern latrines in Gdańsk (northern Poland) 总被引:1,自引:0,他引:1
Fruits, seeds and embryos of Pimenta officinalis Lindl. syn. Pimenta dioica (L.) Merr. (Myrtaceae) have been found in Gdask (northern Poland) in latrines dated to the 18th century. This is one of the first few records of allspice from European archaeobotanical material. The paper presents morphological criteria used for the identification of allspice or myrtle pepper remains and briefly summarises the information on the introduction of this species to the Old World. 相似文献
7.
Ricardo González-Trujillo David Rodriguez Alberto González-Romero Michael R. J. Forstner Llewellyn D. Densmore III Víctor Hugo Reynoso 《Conservation Genetics》2012,13(6):1677-1683
Among the loss of genetic diversity due to population declines, population fragmentation and habitat loss, hybridization also stands as a threat to Morelet’s crocodile (Crocodylus moreletii) populations. Genetic surveys in Belize and the Yucatan Peninsula have detected evidence of hybridization with the American crocodile (C. acutus). Admixture between these two species is most likely driven by human-mediated translocations. Along the central gulf coast of Mexico, C. moreletii populations are presumed to be purebred. To test this, we use nine microsatellite loci and sequence data from the mitochondrial control region to detect if C. acutus alleles have introgressed into populations of C. moreletii from central Veracruz. In 2010, C. moreletii was transferred from Appendix I to II of CITES based on a whole species demographic analysis, which indicated that populations had recovered across its range. Our study shows that populations in central Veracruz are purebred, although they exhibit low levels of genetic diversity most likely caused by inbreeding. Our data also suggest there is fragmentation among populations of C. moreletii, which may lead to further loss of genetic variation. Due the purity and low genetic diversity of C. moreletii populations from central Veracruz, we recommend increased protection and active management practices that take genetic data into account. 相似文献
8.
Koffi Evenyon Kassegne Mickaël J. Mourlam Guillaume Guinot Yawovi Zikpi Amoudji Jeremy E. Martin Kodjo Adika Togbe Ampah Kodjo Johnson Lionel Hautier 《Annales de Paléontologie》2021,107(2):102488
Earliest cetaceans (whales) originated from the early Eocene of Indo-Pakistan, but the group dispersed through most of the oceans of the planet by the late middle to late Eocene. This late Eocene global distribution indicates that important dispersal events took place during the middle Eocene (Lutetian), a globally undersampled time interval that is well documented in the Togolese phosphate series. We report here the first discovery of a partial cetacean cranium from middle Eocene deposits of Togo (West Africa). A 3D model of the cranium and teeth was reconstructed in order to reveal hidden anatomical features. The dental and cranial characteristics of the Togolese specimen recall those of protocetid taxa described in Africa, Asia, and North America, but also display significant differences. In particular, we show that the new specimen shares a number of morphological features with the Togolese taxon Togocetus. Such a hypothesis is further supported by a cladistic analysis including 45 taxa and 167 morphological characters, which recovers the new specimen close to Togocetus as the first offshoot of protocetids. Phylogenetic analysis including all the protocetids remains of Kpogamé confirms the singular diversity of the Togolese phosphate basin, and enables to examine potential connections with faunas from contemporaneous localities in Africa. 相似文献
9.
《Journal of Asia》2020,23(2):430-438
The bacterial community living in the insect gut may play an important role in nutrition, immunity and protection, detoxification of toxins, and inter- and intra-specific communication. Rice leaffolder Cnaphalocrocis medinalis (Guenée) (Lepidoptera: Crambidae) is a notorious pest in rice, and the diversity of the gut bacteria of C. medinalis across life stages are not well understood. Here, the diversity and abundance of the gut bacterial community in C. medinalis through life stages were investigated using Illumina Miseq technology. A total of 22 bacterial phyla, 42 classes, 100 orders, 179 families, 350 genera and 395 species were identified across the different life stages of C. medinalis. Proteobacteria and Firmicutes phyla were the dominant bacterial taxa. Members of the genera Enterococcus, unclassified Enterobacteriaceae, Wolbachia, Acinetobacter, Stenotrophomonas, Microbacterium, Bacillus, Corynebacterium, Lampropedia, and Sphingobacterium were found at all life stages. Enterococcus and unclassified Enterobacteriaceae occupied higher relative abundance among bacteria community in the 2nd to 5th instar larvae, pupae and adults. The structure of bacterial community differed across the life stages of C. medinalis. Our findings will enrich the understanding of gut bacteria in C. medinalis, and will provide foundation and assistance for the development of novel pest management strategies through utilization of microbiota. 相似文献
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Martin Ko??ák John W. M. Jagt Robert P. Speijer Peter Stassen Etienne Steurbaut 《PloS one》2013,8(11)
New coleoid cephalopods, assignable to the order Sepiida, are recorded from the Selandian/Thanetian boundary interval (Middle to Upper Paleocene transition, c. 59.2 Ma) along the southeastern margin (Toshka Lakes) of the Western Desert in Egypt. The two genera recognised, Aegyptosaepia n. gen. and ?Anomalosaepia Weaver and Ciampaglio, are placed in the families Belosaepiidae and ?Anomalosaepiidae, respectively. They constitute the oldest record to date of sepiids with a ‘rostrum-like’ prong. In addition, a third, generically and specifically indeterminate coleoid is represented by a single rostrum-like find. The taxonomic assignment of the material is based on apical parts (as preserved), i.e., guard, apical prong (or ‘rostrum-like’ structure), phragmocone and (remains of) protoconch, plus shell mineralogy. We here confirm the shell of early sepiids to have been bimineralic, i.e., composed of both calcite and aragonite. Aegyptosaepia lugeri n. gen., n. sp. reveals some similarities to later species of Belosaepia, in particular the possession of a distinct prong. General features of the phragmocone and protoconch of the new form are similar to both Belocurta (Middle Danian [Lower Paleocene]) and Belosaepia (Eocene). However, breviconic coiling and the presence of a longer ventral conotheca indicate closer ties with late Maastrichtian–Middle Danian Ceratisepia. In this respect, Aegyptosaepia n. gen. constitutes a link between Ceratisepia and the Eocene Belosaepia. The occurrence of the new genus near the Selandian/Thanetian boundary suggests an earlier origin of belosaepiids, during the early to Middle Paleocene. These earliest known belosaepiids may have originated in the Tethyan Realm. From northeast Africa, they subsequently spread to western India, the Arabian Plate and, probably via the Mediterranean region, to Europe and North America. 相似文献
12.
Prioli AJ Carlo VA Soria TV Prioli SM Pavanelli CS Prioli RA Gomes VN Júlio HF Prioli LM 《Genetics and molecular research : GMR》2012,11(2):1064-1074
The morphological discrimination between the species Astyanax altiparanae and A. asuncionensis of the upper Paraná River and Paraguay River basins, respectively, has always been difficult. Two D-loop haplogroups of A. altiparanae are known, one with the presence (AltoPR) or the absence (AltoPR-D) of a 32-bp block similar to that in A. asuncionensis. We examined these samples to characterize A. altiparanae and verify whether A. asuncionensis occurred in the upper Paraná River prior to the submergence of the Sete Quedas Falls when Itaipu reservoir was impounded. D-loop sequences were analyzed in A. altiparanae of the upper Paraná and Igua?u Rivers and those of A. asuncionensis of the upper Paraguay River. The haplogroup AltoPR was found at all sites of the upper Paraná and Igua?u Rivers, whereas AltoPR-D occurred in the Itaipu reservoir, floodplain and in the Tietê and Grande Rivers. Two haplogroups of A. asuncionensis were identified and both did not have the 32-bp block. However, AltoPR and AltoPR-D differed from one another in 5.1% of their bases and between 8.9 and 12.5% with regard to the haplogroups of the upper Paraguay basin. Further, AltoPR-D occurred in the Grande River upstream the Marimbondo Falls and other older reservoirs than Itaipu. The results reject the hypothesis of the establishment of A. asuncionensis and suggest that the haplogroup AltoPR-D existed in the upper Paraná River before the impounding of the Itaipu reservoir. Moreover, morphological similarity and high genetic variation within the altiparanae/asuncionensis group suggest the existence of a cryptic species complex. 相似文献
13.
Pedro H. N. Braganca Timothy G. Smith Emmanuel J. W. M. N. Vreven Albert Chakona 《Journal of fish biology》2020,97(6):1713-1723
The present study explored the diversity of Nannocharax within southern Africa by implementing three species delimitation methods for a data set consisting of 37 mitochondrial cytochrome oxidase subunit I sequences. Two unilocus coalescent methods, the General Mixed Yule Coalescent (GMYC) and the Bayesian implementation of the Poisson Tree Processes (bPTP), and a genetic distance method, the Automatic Barcode Gap Discovery (ABGD), were applied. Both GMYC and bPTP delimited the same operational taxonomic units (OTUs), revealing a higher diversity for the genus in the region than previously recognised, whereas the ABGD failed to delimit the same candidate species. All methods delimited two species groups, and these are supported based on colouration patterning and morphology; the Nannocharax multifasciatus and the Nannocharax macropterus species groups and the delimited OTUs were assigned to each. Two putative new species were identified, Nannocharax cf. lineostriatus “Okavango” from the Okavango River in Angola and N. cf. lineostriatus “Kwanza” from the Kwanza River system in Angola. The distribution of Nannocharax dageti was confirmed for the Upper Zambezi and extended to the Okavango system, and an identification key for the southern Africa Nannocharax species is provided. 相似文献
14.
This study is an initial survey of the genetic diversity and population structure of the endangered Bonelli’s Eagle (Hieraaetus fasciatus) in SW Europe (Iberia) and NW Africa, two locations where the species has undergone a severe decrease in numbers during the
last decades. It is also the first study in which the mitochondrial control region (CR) has been used to study the genetic
diversity and population structure of this species. Samples were obtained from 72 individuals from Spain, Portugal and Morocco,
and a 253-bp fragment of the mitochondrial control region was amplified and sequenced. Only three polymorphisms were present,
indicating low nucleotide and haplotype diversity. No evidence of genetic structure was found. Several hypotheses may explain
these results, including a possible greater genetic diversity in other regions of the mitochondrial genome or the existence
of a presumed ancient bottleneck (last glaciation), possibly followed by a human-induced more recent one (twentieth century). 相似文献
15.
The qualitative and quantitative structure of the zooplankton community was studied in 11 localities of Lake Xolotlan (Managua). Twelve rotifers, 4 cladoceran and 5 copepods species were identified. Community diversity (Shannon-Wienerindex) is low,viz. 0,83–2.20. At all times, copepods were the most abundant group. Rotifer densities were higher in zones influenced by rivers and organic pollution. Cladocerans were permanently present in low densities. Climatic events (rainfalls and dry periods) determined population fluctuations of the main zooplankton groups. 相似文献
16.
DL Lourenco-Jaramillo AM Sifuentes-Rincón GM Parra-Bracamonte XF de la Rosa-Reyna A Segura-Cabrera W Arellano-Vera 《Genetics and molecular biology》2012,35(2):435-440
DNA from four cattle breeds was used to re-sequence all of the exons and 56% of the introns of the bovine tyrosine hydroxylase (TH) gene and 97% and 13% of the bovine dopamine β-hydroxylase (DBH) coding and non-coding sequences, respectively. Two novel single nucleotide polymorphisms (SNPs) and a microsatellite motif were found in the TH sequences. The DBH sequences contained 62 nucleotide changes, including eight non-synonymous SNPs (nsSNPs) that are of particular interest because they may alter protein function and therefore affect the phenotype. These DBH nsSNPs resulted in amino acid substitutions that were predicted to destabilize the protein structure. Six SNPs (one from TH and five from DBH non-synonymous SNPs) were genotyped in 140 animals; all of them were polymorphic and had a minor allele frequency of > 9%. There were significant differences in the intra- and inter-population haplotype distributions. The haplotype differences between Brahman cattle and the three B. t. taurus breeds (Charolais, Holstein and Lidia) were interesting from a behavioural point of view because of the differences in temperament between these breeds. 相似文献
17.
Is increased chromosomal diversity in house mice from Lombardy (Italy) congruent with genic divergence? 下载免费PDF全文
Claudine Montgelard Josette Catalan Janice Britton‐Davidian 《Biological journal of the Linnean Society. Linnean Society of London》2016,118(2):245-261
Recent studies in metacentric (MC) populations of the house mouse, Mus musculus domesticus, singled out underdominance more so than recombination suppression as the foremost barrier to gene flow. Here, MC populations from Lombardy (Italy) were sampled to identify the nature and strength of the barriers to gene flow. The chromosomal analysis recovered the three major MC populations (abbreviated to IBIN, IGAL, both with 2n = 24 and ICRE, 2n = 22), but revealed the existence of a new one (IONE, 2n = 24) which likely derived from IGAL through a single WART (Whole‐Arm Reciprocal Translocation). This, once again, highlights the paramount role of WARTs in the chromosomal diversification of this subspecies. Contacts between MC and standard populations coincided with rivers confirming these hybrid zones as tension zones. Divergence between populations was estimated using available allozyme data. Although the overall low genetic structure globally agreed with the chromosome structure, a large variation in divergence levels was retrieved that only partially matched the underdominance degree. This disparity from expectations highlighted the additional contribution of physical barriers and geographic isolation to the differential rate of evolution of the MC populations of the house mouse. 相似文献
18.
Species richness of epigeic ants was surveyed in forest islands named cap?es of Brazilian Pantanal and related with their structural complexity. The ants were collected using pitfall traps in 28 cap?es from Rio Negro Farm, in Aquidauana municipality, Mato-Grosso do Sul state, Brazil. The structural complexity of cap?es was evaluated by measuring vegetation density and litter quantity near the pit-fall traps. Seventy-one species, distributed in 26 genera and seven sub-families were found. Ectatomma edentatum Roger (Formicidae: Ectatomminae) and one species of Pheidole were the most frequent species. Species richness was positively correlated only with herbaceous vegetation density of cap?es, supporting the idea that the increase in environmental heterogeneity diminishes species competition, allowing species co-occurrence. 相似文献
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Sergio E. Miquel 《Molluscan research.》2019,39(3):265-279
ABSTRACTA revision of Gastrocopta from the Galápagos Islands (Ecuador) is made. Four new species from Pinzón, Santa Cruz and Floreana Islands are described; species previously known are redescribed and new locations are added. Gastrocopta (Gastrocopta) reibischi is revalidated through new records from Floreana, Isabela and San Bartolomé Islands. Shell shape and the number, morphology and disposition of the apertural barriers support the discrimination of the taxa. The species have cylindrical to pupoid shells; the number of apertural barriers – differentiated as lamellae, folds and nodulae – varies between 4 and 11, almost completely occluding the aperture in the more complex cases. These structures are: angular-parietal, infraparietal, supracolumellar, columellar, subcolumellar lamellae, and supernumerary, basal, infrapalatal, lower-palatal, interpalatal, upper-palatal and suprapalatal folds. In addition to this classic scheme, a supernumerary fold and a nodule are added. Calcareous concretions – pustulae – are found in several species, mainly located in the peristome. The aulacognathous jaw and radular dentition formulae of Gastrocopta (Gastrocopta) clausa and Gastrocopta (Gastrocopta) munita, are described and photographed for the first time. 相似文献