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1.
This article is part of a Special Issue “Parental Care”.Mother–infant bonding is a characteristic of virtually all mammals. The maternal neural system may have provided the scaffold upon which other types of social bonds in mammals have been built. For example, most mammals exhibit a polygamous mating system, but monogamy and pair bonding between mating partners occur in ~ 5% of mammalian species. In mammals, it is plausible that the neural mechanisms that promote mother–infant bonding have been modified by natural selection to establish the capacity to develop a selective bond with a mate during the evolution of monogamous mating strategies. Here we compare the details of the neural mechanisms that promote mother–infant bonding in rats and other mammals with those that underpin pair bond formation in the monogamous prairie vole. Although details remain to be resolved, remarkable similarities and a few differences between the mechanisms underlying these two types of bond formation are revealed. For example, amygdala and nucleus accumbens–ventral pallidum (NA–VP) circuits are involved in both types of bond formation, and dopamine and oxytocin actions within NA appear to promote the synaptic plasticity that allows either infant or mating partner stimuli to persistently activate NA–VP attraction circuits, leading to an enduring social attraction and bonding. Further, although the medial preoptic area is essential for maternal behavior, its role in pair bonding remains to be determined. Our review concludes by examining the broader implications of this comparative analysis, and evidence is provided that the maternal care system may have also provided the basic neural foundation for other types of strong social relationships, beyond pair bonding, in mammals, including humans.  相似文献   

2.
The study of parasitism related to biological invasion has focused on attributes and impacts of parasites as invaders and the impact of introduced hosts on endemic parasitism. Thus, there is currently no study of the attributes of hosts which influence the invasiveness of parasites. We aimed to determine whether the degree of domestication of introduced mammalian species – feral introduced mammals, livestock or pets, hereafter ‘D’ – is important in the spillover of introduced parasites. The literature on introduced parasites of mammals in Chile was reviewed. We designed an index for estimating the relevance of the introduced host species to parasite spillover and determined whether the D of introduced mammals predicted this index. A total of 223 introduced parasite species were found. Our results indicate that domestic mammals have a higher number of introduced parasites and spillover parasites, and the index indicates that these mammals, particularly pets, are more relevant introducers than introduced feral mammals. Further analyses indicated that the higher impact is due to higher parasite richness, a longer time since introduction and wider dispersal, as well as how these mammals are maintained. The greater relevance of domestic mammals is important given that they are basically the same species distributed worldwide and can become the main transmitters of parasites to native mammals elsewhere. This finding also underlines the feasibility of management in order to reduce the transmission of parasites to native fauna through anti-parasitic treatment of domestic mammals, animal-ownership education and the prevention of importing new parasite species.  相似文献   

3.
Roger  Lubbock 《Journal of Zoology》1975,176(1):115-157
An account is given of pseudochromid fishes from the northwest Indian Ocean and Red Sea. Thirteen species are recorded; four new species of Pseudochromis and two new species of Chlidichthys (all from the Red Sea) are described. Keys are provided, and details are given of the ecology, maintenance in aquaria, and spawning of pseudochromids. As an appendix, a new name is proposed for Pseudochromis punctatus Kotthaus, 1970.  相似文献   

4.
A programme of study using hair follicle mites of man, dog, and other mammals is presented which has been successful in stimulating student interest in symbiosis. Brief background information on these mites, with illustrations, is provided as well as details of laboratory procedures for secondary school through college level classes. Suggestions for more advanced or independent studies using these mites are also made so that exceptional, career-oriented students and their teachers can explore adaptations to symbiosis in depth.  相似文献   

5.
T.C. Pellmar 《Life sciences》1981,28(20):2199-2205
At one time neurotransmitters were thought of as chemical agents that simply depolarized or hyperpolarized a postsynaptic cell. Now it is known that transmitters can do much more. Biochemical processes, most notably the consequences of activation of adenylate cyclase, are subject to neurotransmitter control. Transmitters can alter a cell's sensitivity to another neurotransmitter; this is exemplified by the action of aspartate in enhancing responses to glutamate. Another action of transmitters is the subject of this review: control of voltage-dependent neuronal currents.Voltage-dependent processes are necessary for the normal function of neuronal systems. Potassium, sodium, and calcium currents that turn on and off with changes in membrane potential are responsible for action potentials and slow-wave (or burst firing) activity. Transmitter control of these ionic currents allows direct synaptic regulation of basic electrophysiological events.Discussion of the voltage-dependent actions of transmitters in neuronal systems will be divided into four areas: (a) broadening and narrowing of action potentials, (b) modulation of burst firing activity, (c) blockade of a voltage-dependent potassium conductance, and (d) induction of a voltage-dependent calcium current. The membrane currents underlying voltage-dependent events will be reviewed only as necessary to understanding transmitter effects. The reader is referred to a recent review for further details on some of these currents (1).  相似文献   

6.
This review considers the factors involved in the regulation of feeding and metabolism in response to food deprivation using Caenorhabditis elegans as a model organism. Some of the sensory neurons and interneurons involved in food intake are described, together with an overview of pharyngeal pumping. A number of chemical transmitters control feeding in C. elegans including 5-hydroxytryptamine (5-HT, serotonin), acetylcholine, glutamate, dopamine, octopamine, and tyramine. The roles of these transmitters are modified by neuropeptides, including FMRFamide-like peptides (FLPs), neuropeptide-like protein (NLPs), and insulin-like peptides. The precise effects of many of these neuropeptides have yet to be elucidated but increasingly they are being shown to play a role in feeding and metabolism in C. elegans. The regulation of fat stores is complex and appears to involve the expression of a large number of genes, many with mammalian homologues, suggesting that fat regulatory signalling is conserved across phyla. Finally, a brief comparison is made between C. elegans and mammals where for both, despite their evolutionary distance, classical transmitters and neuropeptides have anorectic or orexigenic properties. Thus, there is a rationale to support the argument that an understanding of the molecular and genetic basis of feeding and fat regulation in C. elegans may contribute to efforts aimed at the identification of targets for the treatment of conditions associated with abnormal metabolism and obesity.  相似文献   

7.
Amino acids in the central nervous system can be divided into non-neurotransmitter or neurotransmitter depending on their function. The measurement of these small molecules in brain tissue and extracellular fluid has been used to develop effective treatment strategies for neuropsychiatric and neurodegenerative diseases and for the diagnosis of such pathologies. Here we describe the separation and detection techniques that have been used for the measurement of amino acids at trace levels in brain tissue and dialysates. An overview of the function of amino acid transmitters in the brain is given. In addition, the type of sampling techniques that are used for the determination of amino acid levels in the brain is described.  相似文献   

8.
I developed a modified leg harness for mounting radiotelemetry transmitters to small birds, which includes a weak link that allows telemetry equipment to be shed. Over 4 years, I mounted 62 transmitters on 49 Tuamotu kingfishers (Todiramphus gambieri) using weak-link harnesses. Kingfishers retained 86% of transmitters for the duration of monitoring periods (23–66 days) whereas 22 of 23 transmitters were shed from birds resighted after 6–15 months. Apparent mortality was no higher for radio-marked birds than for birds without transmitters. The weak-link harness is an improvement to existing transmitter attachment techniques and provides a useful, effective, and ethical means of studying bird movements. © 2011 The Wildlife Society.  相似文献   

9.
The use of the sample variance-to-mean ratio as a measure of deviation from randomness in spatial pattern is reviewed. The likelihood ratio method of constructing a statistical test for the equality of several population variance-to-mean ratios is described, and details are provided for the special case where counts are modelled as arising from a negative binomial distribution. This test is illustrated by application to example data sets in ecology. Likelihood ratio tests represent a general methodology whereby relationships among several indices of aggregation can be systematically investigated, provided one is able to specify a suitable parametric form for the underlying distributions.  相似文献   

10.
The lung lining and its surfactant have been studied in one species from each of the amphibian sub-classes Anura, Urodela, and Apoda. The surfactant was studied by observation of bubbles derived from the lungs, the morphology by electron microscopy. Other details of the apodan are also given.
The surfactant layers of Rana temporaria and Ichthyophis (species unknown) resemble one another, being somewhat less stable than that of mammals. That of Triturus vulgaris is even less stable, and shows qualitative differences from the other two. Nevertheless, it can reduce the surface tension to 2 mN/m.
The epithelial cells of amphibian lungs cannot be divided into two clearly defined types, as can those of mammals. Microvilli are present on the alveolar surface of all these cells. In the lungs of Rana and Ichthyophis the lining cells contain numerous lamellated osmiophilic bodies (which are intracellular depots of surfactant); in the former their appearance is mainly cross-barred, in the latter mainly concentric. Similar bodies exist in the lung epithelial cells of Triturus but are relatively rare.  相似文献   

11.
Abstract.  The Encarsia longifasciata group is established and revised, and its relationship to other species groups of Encarsia is discussed with reference to biological, morphological and molecular evidence. Principal component analysis on all available specimens provided supporting evidence for the existence of five species, two of which are described herein as new: E. dewa Pedata & Polaszek, sp.n and E. prinslooi Pedata & Polaszek, sp.n. All species are either diagnosed or described, and illustrated, and information is given on their distribution and host range. Additional information on the biology and larval stages, and scanning electron micrographs of morphological details, are provided for E. arabica Hayat. A preliminary phylogenetic study using 28S D2 rDNA sequence data for E. arabica was inconclusive, but suggested possible affinities between the longifasciata and parvella species groups. An illustrated dichotomous key to all species of the E. longifasciata group is given.  相似文献   

12.
A dynamic similarity hypothesis for the gaits of quadrupedal mammals   总被引:13,自引:0,他引:13  
The dynamic similarity hypothesis postulates that different mammals move in a dynamically similar fashion whenever they travel at speeds that give them equal values of a dimensionless parameter, the Froude number. Thus, given information about one species, it could be possible to predict for others relationships between size, speed and features of gait such as stride length, duty factor, the phase relationships of the feet and the patterns of force exerted on the ground.
Data for a diverse sample of mammals have been used to test the hypothesis. It is found to be tenable in many cases when comparisons are confined to quadrupedal mammals of the type described by Jenkins (1971) as "cursorial". Most mammals of mass greater than 5 kg are of this type. Although the hypothesis applies less successfully to comparisons between cursorial and non-cursorial mammals it is shown to be a reasonable approximation even for such comparisons and for comparisons between quadrupedal mammals and bipedal mammals and birds.  相似文献   

13.
Abstract  The euparine genus Cnematoplatys Schmidt, with seven species, is reviewed, including one species, C. yorkensis described as new. The generic diagnosis is revised, a lectotype of the type species, C. benardi Schmidt, is designated, a key to the species is provided and pertinent morphological details are illustrated. All data on taxonomy and available data on distribution are given, and a cladistic analysis is included to test the monophyly of the genus.  相似文献   

14.
A new approach to the problem of correspondence between primary structures of polypeptides and their tertiary structures is presented. This approach is based on the following statement of the problem: what will be the statistical properties of tertiary structures provided that the statistical properties of primary structures (e. g. the ratio of polar and unpolar residues) are given? It is discussed whether such statement is useful for the investigation of the prebiological evolution and protein folding. It is emphasized that the basic point here is to determine the configurational entropy of the chain, i. e., the number of foldings which lead to a given density distribution space. Hence, the auxiliary problem of the ideal heteropolymer collapse in the external field is considered. This problem is investigated numerically in the case when the field is localized in the small region in space. It is shown that such geometrical characteristics as the size of a globule are not sensitive to the details of primary structure when the chain is a random coil, and become sensitive to such details in the opposite globular case. These characteristics in the globular state can be described by the stable probability distribution function which does not depend upon chain length. Geometric characteristics of the chain exhibit especially strong dependence upon the primary structure in the region of coil-globule transition which is of the second order for the ensemble of chains.  相似文献   

15.
The wide-spread use of and demand for myelin basic protein for immunologic studies has prompted us to re-examine the details of its isolation from CNS tissue of various species. The procedure described in this communication for the isolation and purification of myelin basic protein does not require column chromatography and is therefore suitable for large scale preparation of a reasonably pure product with simple laboratory equipment. If certain precautions are taken, the yield and quality of the product are reproducible. Certain contaminants which may accompany myelin basic protein during purification by procedures currently in use are pointed out, and their possible influence on the immunologic behavior of myelin basic protein is discussed. Suitable electrophoretic techniques for the detection of these contaminants as well as details for their removal from the myelin basic protein are described.  相似文献   

16.
Appropriate monitoring tools are essential for assessing the effectiveness of management for all threatened insect taxa. In New Zealand the large-bodied flightless orthopterans in the genus Deinacrida have mostly been monitored by searching through habitat during the day or spotlighting at night but this is time consuming and the results depend on the skill of the searcher. Recently, footprint tracking tunnels, similar to those used for monitoring small mammals in New Zealand, were found to be effective for detecting adults of various giant weta species. In this study, we compared the abundance of Cook Strait giant weta (CSGW) in the vicinity of the tunnels, estimated by mark-recapture, with the number of tracking tunnels tracked by weta. We found strong indications that both baited and unbaited tracking tunnels can be used to estimate the number of adult weta present but that this probably depends on their responses to meteorological conditions which are not yet understood. Our results also show that footprint tracking tunnels are more effective for detecting adult CSGW than searching for these insects at night and that baiting tracking tunnels with peanut butter increases their effectiveness for detecting adult CSGW. We confirmed how far Cook Strait giant weta moved each night on Matiu-Somes Island by attaching transmitters to them and found that day roosts of three adult males were on average 8.6 m apart each day and those of adult females were on average 21.3 m apart. Both the low recapture rates of marked adult CSGW and the nightly displacements of those with transmitters suggest that adult CSGW show no site fidelity and are clearly capable of moving large distances each night. However, an individual weta is unlikely to track more than one tunnel per night if tunnels are 30 m apart. Tracking tunnels have the potential to be used with some other insects, provided their footprints are diagnostic. An advantage of using tracking tunnels is that they are non-lethal and would therefore be particularly suitable for monitoring other large threatened insect taxa.  相似文献   

17.
In a study of wolf pup survival, intraperitoneal radio transmitters were surgically implanted in 53 (27 male and 26 female) 3.5- to 8-wk-old Eastern wolf (Canis lycaon) pups at den sites in Algonquin Provincial Park, Ontario, Canada, over two whelping seasons (2004 and 2005). Pups were manually removed from dens and initially injected with butorphanol at a dosage of 0.1 mg/kg for sedation and intra-operative analgesia. Anesthesia was induced and maintained with 3% sevoflurane in oxygen via a face mask. Meloxicam (0.3 mg/kg intramuscularly) was given to provide additional analgesia. All surgeries were completed without complications, and pups were readily accepted back into the packs. No postoperative complications were identified, but two pups from a single litter drowned as a result of being moved by the pack to a flooded den following the surgery. In five pups necropsied following natural deaths, transmitters were found lying free within the peritoneal cavity, and there was no evidence of infection at the surgical site or peritonitis. Inhalation anesthesia provided extremely rapid induction (1 min) and recovery (<3 min) and was completely controllable with no residual anesthetic effects. The equipment for inhalation anesthesia was readily portable in field packs, and it has considerable advantages over injectable drugs for small and very young animals such as wolf pups. The utility of the procedure is demonstrated by the minimal effect it had on subsequent pup survival, the rapid recovery of pups following surgery, and the lack of long-term complications as determined by necropsies of pups following natural deaths.  相似文献   

18.
The Src homology 3 (SH3) domain-containing peroxisomal membrane protein Pex13p is an essential component of the import machinery for matrix proteins and forms a binding site for the peroxisomal targeting type I (PTS1) receptor Pex5p. The interaction between these two proteins can be described as novel in several ways. In the yeasts Saccharomyces cerevisiae and Pichia pastoris, the SH3 domain itself is responsible for the interaction but not via the typical P-x-x-P motifs that are common to SH3 ligands as Pex5p lacks such a motif. Instead, a region of Pex5p containing a W-x-x-x-F/Y motif is crucial for this binding. In mammals, again W-x-x-x-F/Y motifs appear to be important for the interaction but the SH3 domain seems not to be the site for Pex5p binding, this being located in the N-terminus of Pex13p. Despite these differences in the details of the Pex13p-Pex5p interaction, the association of the two proteins is a crucial step in Pex5p-mediated protein import into peroxisomes in both yeasts and mammals.  相似文献   

19.
The full publication of Ardipithecus ramidus has particular importance for the origins of hominin bipedality, and strengthens the growing case for an arboreal origin. Palaeontological techniques however inevitably concentrate on details of fragmentary postcranial bones and can benefit from a whole-animal perspective. This can be provided by field studies of locomotor behaviour, which provide a real-world perspective of adaptive context, against which conclusions drawn from palaeontology and comparative osteology may be assessed and honed. Increasingly sophisticated dynamic modelling techniques, validated against experimental data for living animals, offer a different perspective where evolutionary and virtual ablation experiments, impossible for living mammals, may be run in silico, and these can analyse not only the interactions and behaviour of rigid segments but increasingly the effects of compliance, which are of crucial importance in guiding the evolution of an arboreally derived lineage.  相似文献   

20.
The classification of the Neotropical genera of the Geometrinae is reviewed and 38 genera are recognized (including one nomen dubium). Seven generic synonyms are newly established and the genus Gnathosocia is described as new. Other changes established in this work include 1 species synonym and 36 new or reinstated combinations. A key to genera, based on external features, is provided for their identification. External features and genitalia of representatives of each genus are illustrated. All the 506 known Neotropical species and subspecies of Geometrinae are catalogued and details of type material, examined extensively, are given.  相似文献   

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