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1.
Abstract. 1. We tested a prediction from contemporary foraging theory that animals should decrease their allocation of energy to the searching of individual patches when interpatch travel costs decrease.
2. We used individual Rhagoletis pomonella Walsh (Diptera: Tephritidae) females foraging for oviposition sites (= Crataegus fruit) in a host tree which was surrounded by four other trees at varying distances.
3. We found that flies generally invested less search, measured as time spent searching a tree or number of leaves visited on a tree, when neighbouring trees were nearby than when farther away.
4. Under our test conditions, flies appeared to have difficulty locating neighbouring trees at a distance of more than 1.6 m.
5. Our study calls into question the interpretation of search effort by insects within resource patches in the absence of information on interpatch distances. 相似文献
2. We used individual Rhagoletis pomonella Walsh (Diptera: Tephritidae) females foraging for oviposition sites (= Crataegus fruit) in a host tree which was surrounded by four other trees at varying distances.
3. We found that flies generally invested less search, measured as time spent searching a tree or number of leaves visited on a tree, when neighbouring trees were nearby than when farther away.
4. Under our test conditions, flies appeared to have difficulty locating neighbouring trees at a distance of more than 1.6 m.
5. Our study calls into question the interpretation of search effort by insects within resource patches in the absence of information on interpatch distances. 相似文献
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Abstract. 1. Female apple maggot (Rhagoletis pomonella Walsh) flies held in field cages usually oviposited in an unparasitized (non-pheromone marked) fruit when it was encountered.
2. Oviposition in a previously parasitized (pheromone marked) fruit depended upon the time since the last oviposition (TSLO) and the percentage of infested fruit encountered during search for oviposition sites.
3. Previous theories of host acceptance suggest that the acceptance or rejection of a host should depend dichotomously on time since last oviposition and the fraction of marked hosts in the last five encounters. The experiments, however, show considerable variability and are thus not consistent with the theory.
4. A new theory for the experiments is introduced. This model involves physiological (egg complement) and informational state variables and leads to intuitive understanding of the experimental results. In particular, the model shows how the plasticity in oviposition site selection may arise from fitness maximizing behaviour. Alternative models are also discussed. All of the models stress the importance of physiological and informational states. 相似文献
2. Oviposition in a previously parasitized (pheromone marked) fruit depended upon the time since the last oviposition (TSLO) and the percentage of infested fruit encountered during search for oviposition sites.
3. Previous theories of host acceptance suggest that the acceptance or rejection of a host should depend dichotomously on time since last oviposition and the fraction of marked hosts in the last five encounters. The experiments, however, show considerable variability and are thus not consistent with the theory.
4. A new theory for the experiments is introduced. This model involves physiological (egg complement) and informational state variables and leads to intuitive understanding of the experimental results. In particular, the model shows how the plasticity in oviposition site selection may arise from fitness maximizing behaviour. Alternative models are also discussed. All of the models stress the importance of physiological and informational states. 相似文献
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MICHEL RENOU PHILIPPE LUCAS JEAN-CHRISTOPHE DORE BERNARD LALANNE-CASSOU† JEAN-PIERRE CHAMBON CHRISTIAN COCQUEMPOT‡ 《Physiological Entomology》1991,16(1):87-97
Abstract A comparative study of the olfactory responses to pheromone compounds was performed in twenty-four species of Hadeninae. Electroantennograms (EAG) were recorded on male moths in response to thirty compounds and the response profiles of each species were analysed by factorial correspondence analysis. A limited number of molecules were found active and the most effective stimuli were Z9 tetradecenes and Z11 hexadecenes. The species of the Mythimna genus were most sensitive to aldehydes. Tholera decimalis did not respond to any of the molecules tested. The species belonging to the Mamestra and the Orthosia genera responded to a variety of molecules and no simple correlation was found between the genus and the EAG sensibility. Pheromone reception is discussed in relation to the taxonomy and the evolution of olfactory communication in Hadeninae. 相似文献
7.
BERNARD P. LANE RONALD E. GORDON 《Differentiation; research in biological diversity》1979,14(1-3):87-93
Mild mechanical abrasion of tracheal epithelium of Vitamin A deficient rats removed the superficial cells and spared basal cells which divided to repopulate the damaged area. The proliferative cells passed through a period of DNA synthesis with the greatest numbers of thymidine incorporating cells in samples labelled 22 h after injury. A peak of cell division occurred at 32 h and there was no further DNA synthesis or cell division. The area of wounding exhibited squamous metaplasia while normal pseudostratified muco-ciliary structure was retained by adjacent epithelium which had not been injured. The data indicates that squamous metaplasia in the respiratory epithelium in longstanding Vitamin A deficiency is due to redirected differentiation of basal cells and is seen only after mitotic activity has occurred. 相似文献
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PASCAL NEIGE DIDIER MARCHAND BERNARD LAURIN 《Lethaia: An International Journal of Palaeontology and Stratigraphy》1997,30(2):145-155
Ontogenetic and then heterochronic approaches are used here to analyze sexual differentiation within two well-known Jurassic dimorphic species. This analysis compares two ways of determining the relative biological age of ammonites, one using size (diameter) and the other the number of septa as a proxy of age. The shape standard is established from factor analysis of morphological and growth parameters. Size-age-shape relationships are analyzed on the basis of a new heterochronic representation. When diameter is used as a proxy of age, microconch morphs are globally considered to be progenetic compared with macroconch morphs. When size and age are determined separately and shape is included, (1) Ebrayiceras jactatum (microconch morph) has a shorter period of growth (progenesis) with acceleration of shape compared with its macroconch morph ( Morphoceras macrescens ), (2)( Cardioceras cordatum (microconch morph) has a shorter period of growth (progenesis) coupled with a slower rhythm of growth (dwarfism) compared with its macroconch morph. These findings emphasize the complex relationship between supposed sexual dimorphs in ammonites when size and age standards can be separated, as well as the need for an ontogenetic approach. 相似文献
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EWA PIETRYKOWSKA‐TUDRUJ BERNARD STANIEC ALEXEY SOLODOVNIKOV 《Systematic Entomology》2012,37(2):360-378
Quedius antipodum Sharp is an endemic species from New Zealand. Here we describe its larva, the first of the species‐rich group of the south temperate ‘Quedius’ spp. This finding throws light on the controversy between the conventional systematics of Quedius Stephens and newer phylogenetic analyses, both of which are based on non‐larval characters only. We compare the larva of Q. antipodum with those of the north temperate Quedius (Quediina), where it was traditionally placed, and with the known larvae of Amblyopinina, a group where Q. antipodum was placed by recent phylogenetic studies. Sister‐group relationships of Q. antipodum within the tribe Staphylinini are explored based on larvae by means of parsimony analysis: 77 morphological characters scored for 20 species from 17 genera. Consistent with the adult morphology and DNA sequences, larvae‐based cladistic analysis confirms that Q. antipodum should not be placed in the north temperate genus Quedius. However, larval analysis alone remains dubious with respect to finding the exact sister relationships of that species. 相似文献