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41.
Judy Stamps 《Animal behaviour》2003,66(1):1-13
Interest in relationships between behaviour and development has been spurred by research on related topics, including phenotypic plasticity, parental effects, extragenetic inheritance, individual differences and trait syndromes. Here, I consider several emerging areas of research in the interface between behaviour and development, with a focus on behavioural processes that are likely to affect the development and maintenance of interindividual variation in a wide array of morphological, physiological and behavioural traits. Using a norm of reaction approach, I introduce and illustrate the complexities of phenotypic development. Next, I consider the implications of environmental selection and niche construction for phenotypic development, and consider why these behavioural processes are likely to encourage the development and maintenance of repeatable, stable individual differences and trait syndromes. Parental effects involving behaviour also affect the development of a wide array of phenotypic traits; differential allocation is a currently underappreciated type of parental effect, by which males can affect the development of their offspring via nongenetic means, even if those males have no contact with their young. Behavioural parental effects also contribute to extragenetic inheritance, and recent studies suggest that this phenomenon may be more widespread than previously suspected. The effects of behavioural processes on phenotypic development have interesting implications for problems in related disciplines (e.g. ecology, evolution and conservation biology), providing additional impetus for future research on the effects of behavioural mechanisms on the development of behavioural and other traits. Copyright 2003 Published by Elsevier Ltd on behalf of The Association for the Study of Animal Behaviour. 相似文献
42.
Female mate choice tactics in a resource-based mating system: field tests of alternative models 总被引:7,自引:0,他引:7
Abstract In this study we test theoretical models of female mate choice tactics in natural populations of pine engravers, Ips pini (Say) (Coleoptera: Scolytidae), a species with a resource-based mating system and high search costs. We first develop distinguishing predictions for each of four models of mate choice: random, comparison tactics, and fixed and adjustable thresholds. These predictions relate to commonly collected field data that include the visiting behavior of females and the quality of accepted and rejected mates. Using these types of data, we conclude that pine engravers use an adjustable threshold mate choice tactic because females often accepted the first male encountered, rarely revisited males, visited similar numbers of males in patches of different quality, accepted higher-quality males than those they rejected even on their first encounter with a male in a patch, and had higher acceptance thresholds in high-quality patches than in low-quality patches. This adjustable threshold tactic is consistent with a one-step decision rule and is predicted to occur in species such as pine engravers in which search costs are high and females have information about patch quality before beginning a search in a patch. 相似文献
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Human alveolar macrophage fibronectin: synthesis, secretion, and ultrastructural localization during gelatin-coated latex particle binding 总被引:14,自引:4,他引:10 下载免费PDF全文
Human pulmonary alveolar macrophages synthesized and secreted several characteristic high molecular weight proteins for at least 7 d in vitro. Immunoprecipitates of medium and cell lysates from metabolically labeled cultures with specific anti-human plasma fibronectin IgG contained one major labeled polypeptide of molecular weight 440,000 (unreduced) or 220,000 (reduced). An identical polypeptide in conditioned medium from radiolabeled macrophages bound specifically to gelatin-Sepharose, demonstrating that alveolar macrophages synthesized and secreted a molecule immunologically and functionally similar to fibronectin. Fibronectin was the major newly synthesized and secreted polypeptide of freshly harvested alveolar macrophages. Pulse-chase experiments revealed that newly synthesized fibronectin was rapidly secreted into medium, approximately 50 percent appearing by 1 h and 80 percent by 8 h. Immunoperoxidase staining using antifibronectin F(ab’)(2)-peroxidase conjugates revealed the majority of immunoreactive fibronectin to be intracellular, localized to endoplasmic reticulum and Golgi apparatus. No extracellular matrix fibronectin was visualized, and cell surface staining was rarely seen, usually appearing only at sites where cells were closely apposed and not at sites of macrophage-substrate attachment. Similar immunostaining of fibroblast cultures revealed cell surface-associated fibrillar fibronectin. Ultrastructural localization of fibronectin during binding and phagocytosis of gelatin-coated and plain latex particles revealed fibronectin only on gelatin-latex beads and at their cell binding sites. Neigher plain latex beads nor their cell membrane binding sites stained for fibronectin. These results demonstrate that fibronectin is a major product of human alveolar macrophages, is rapidly secreted, and is localized at cell membrane binding sites for gelatin-coated particles. In view of the known binding properties of fibronectin, it may serve as an endogenous opsonic factor promoting the binding of staphylococcus, denatured collagen, fibrin, or other macromolecules to macrophages in the lower respiratory tract. 相似文献
46.
On the phospholipids of Bacillus megaterium 总被引:12,自引:0,他引:12
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Phylogenetic screening of the human genome: identification of differentially hybridizing repetitive sequence families 总被引:1,自引:0,他引:1
The phi-screen, a method of phylogenetic screening, can be employed to
detect repetitive sequence families that differentially hybridize between
closely related species. Such differences may involve sequence divergence
or variations in copy number, including total presence versus absence of a
family of repeated DNA. We present the results of a phi-screen comparing
the human genome to that of the prosimian, Galago crassicaudatus. Three
human repetitive families that are divergent or not present in galago have
been detected. One of these families is described in detail; it is similar
among the anthropoids but is present in a lower copy number and/or
divergent form in prosimians. The family is clearly related to the
transposon-like human element (THE) described by Paulson et al. (1985).
THEs have long terminal repeats reminiscent of retroviruses but are unique
in that they have no sequence similarity to known mammalian retroviruses.
The sequence of a solo long terminal repeat, found unassociated with THE
internal sequence, is presented. This family member, THE p2, is bordered by
a 5-bp target-site repeat and is interrupted by the insertion of an Alu
element. A solo THE element sequenced by Wiginton et al. (1986) contains an
insertion of Alu at precisely the same position as does THE p2.
相似文献
49.
The alcohol dehydrogenase (Adh) region from five planitibia subgroup
species of Hawaiian picture-wing Drosophila has been cloned. A total of 15
kb of DNA in and around the Adh gene has been compared among the five
species. Genetic distances were calculated to determine evolutionary
relationships. These distances agree with previous distances determined by
protein polymorphism and DNA hybridization techniques and can be
interpreted in terms of specific island colonization and speciation
(founder) events over the past 5 Myr. Examination of the restriction maps
of the cloned Adh region from the five species shows many instances of
small deletions, insertion of a transposable element in D. heteroneura, and
the existence of a highly variable region on the 3' side of the Adh gene.
Clustering relationships and rates of DNA change are calculated and
compared with the relationship found for other species of Drosophila.
相似文献
50.