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1.
The development of alatae of the green peach aphid, Myzus persicae, as gynoparae rather than as virginoparae was investigated with regard to the number of exposures to a long-night (LN) regime of 15 h darkness per diem which the aphids experienced before and/or after their birth. The minimum number of exposures to LN that resulted in all of the alatae developing into gynoparae was two prenatal plus one postnatal or one prenatal plus two postnatal, provided the scotophases in these treatments were at least 12 h long. A cumulative effect of several successive exposures to LN was also evident when the presumptive alatae were exposed to LN either from birth or not until several days after birth. Fewer exposures to LN were needed in the former case.
Zusammenfassung Die Entwicklung von Alatae der grünen Pfirsichblattlaus, Myzus persicae, hauptsächlich zu Gynoparae, eher als zu Virginoparae, wurde im Hinblick auf den Einfluss der Anzahl an Langnächten (LN: 15 Studen Dunkelheit pro Tag), denen die Aphiden vor und/oder nach der Geburt ausgesetzt waren, untersucht. Zur ausschliesslichen Entwicklung aller Alatae zu Gynoparae waren mindestens 2 prenatale und eine postnatale LN-Exposition oder eine prenatale und 2 postnatale LN-Expositionen notwendig, vorausgesetzt die Dunkelphasen betrugen mindestens 12 Stunden. Ausserdem zeigte sich ein kumulativer Effect durch mehrere, aufeinanderfolgende LN-Expositionen, wenn die Alatae diesen von Geburt an, oder einige Tage nach der Geburt, ausgesetzt waren. Im ersten Fall waren weniger LN-Expositionen notwendig.相似文献
2.
Viktor Reinhardt 《Zoo biology》1985,4(3):295-300
During twelve 2-h observation sessions courtship behavior was recorded among seven musk-ox males (Ovibos moschatus) kept in a paddock together with six females. The animals were sexually mature and of the same age. Foreleg kicking and genital sniffing were more common than mounting. All three activities were of a nonaggressive nature but were shown almost exclusively by dominants toward subordinate partners. Assuming the role of courted females, recipients were never the target of aggressive acts. It was concluded that courtship among mature musk-ox males functions as a nonaggressive reinforcement of dominance, promoting low-risk coexistence of males. 相似文献
3.
Ursula Bartecki 《Primates; journal of primatology》1986,27(2):173-184
A study was carried out on the social position of 12 subadult males of a semifreeranging Barbary macaque population during
the non-mating season. The social position was measured in terms of spatial as well as interactive parameters. The subadult
males had social contacts to members of nearly all other age-sex classes but showed clear preferences for same-sexed partners.
Besides this differences were found between 5- and 6-year-old males with respect to their interaction profiles and the preference
for special classes of interaction partners. The terms “peripheral-central” is discussed with reference to the social structures
of macaque societies. The data of the present study indicate that the social position of subadult male Barbary macaques can
not be described by one of these terms exclusively. The results are compared to other studies on Barbary macaques and other
macaque species. It is concluded that in macaque societies subadult males are not obligatorily forced to live at the periphery
or to abide. It is proposed not to postulate stiff social structures but to put more emphasis on the range of variation among
macaque species. 相似文献
4.
5.
David A. Hill 《Primates; journal of primatology》1990,31(1):33-50
The social relationships of adult male rhesus macaques (Macaca mulatta) in Group I of the Cayo Santiago colony were studied over a period of 14 months. Relationships were found in which adult
males and sexually mature females were persistently close to one another in nonsexual contexts, both within and across seasons.
Males of long tenure and high dominance rank tended to have more female partners, and more persistent relationships, than
more recent immigrants of lower rank. Correlations with length of tenure were stronger than those with dominance rank. Closely-related
females tended to have persistent relationships with the same male. In most cases the female was primarily responsible for
maintaining proximity in non-sexual contexts.
Dyads which were persistently within 5 m of each other in the birth season were more likely to form a consortship in the subsequent
mating season than those which had a brief relationship. A similar tendency was apparent in the 1 m data but it was not statistically
significant. There was no association between persistent proximity during the birth season and the occurrence of long, or
multiple consortships, nor with the maintenance of proximity or direction of grooming between consort partners. The pattern
of consortships was not closely related to the formation of persistent relationships in the subsequent birth season. Females
occasionally received protection from their male partners and, in some cases, spent more time in the feeding corral with them
than did other females.
Affiliative relationships can be very enduring and may have long-term benefits that were not apparent during the study period. 相似文献
6.
7.
WU Zhishan Keith R. Hopper Paul J. Ode Roger W. Fuester CHEN Jia-hua George E. Heimpel 《Insect Science》2003,10(2):81-93
Abstract In haplodiploid Hymenoptera, unfertilized eggs produce haploid males while fertilized eggs lead to diploid females under most circumstances. Diploid males can also be produced from fertilization under a system of sex determination known as complementary sex determination (CSD). Under single-locus CSD, sex is determined by multiple alleles at a single sex locus. Individuals heterozygous at the sex locus are female while hemizygous and homozygous individuals develop as haploid and diploid males, respectively. In multiple-locus CSD, two or more loci, each with two or more alleles, determine sex. Diploid individuals are female if one or more sex loci are heterozygous, while a diploid is male only if homozygous at all sex loci. Diploid males are known to occur in 43 hymenopteran species and single-locus CSD has been demonstrated in 22 of these species. Diploid males are either developmentally inviable or sterile, so their production constitutes a genetic load. Because diploid male production is more likely under inbreeding, CSD is a form of inbreeding depression. It is crucial to preserve the diversity of sex alleles and reduce the loss of genetic variation in biological control. In the parasitoid species with single-locus CSD, certain precautionary procedures can prevent negative effects of single-locus CSD on biological control. 相似文献
8.
Between June 1986 and October 1992, in 3 periods totaling 12 months, we studied social organization of pigtailed langurs (Simias concolor)in the Pagai Islands, Indonesia. With one possible exception, all of 20 family groups contained only 1 adult male each. Nine
of them contained only 1 adult female,and 11 contained ≥2 adult females. Mean group size is 4.1 individuals. Home ranges varied from 7 to 20 ha, and population
density averages 21 animals/km
2
. Simias concoloris sexually dimorphic⤖n a museum sample males average 29% heavier than females, and their canine teeth are on average nearly
twice the length of female canines. Combined data from several studies indicate that 60% of S. concolorgroups contain an adult pair plus young,and 40% are multifemale groupings. We sggest that any 1-male mating system that comprises a mixture of 1-female and multifemale
groups in the same population should be termed monandry. 相似文献
9.
A 4-year study (1989–1992) of a population of Lipophrys pavo living in a brackish lagoon (Maugio, France) revealed three types of male during the spawning season (April to September): (i) nest-breeder males which are territorial, and have well-developed secondary sexual characteristics; (ii) non-functional males which were abundant only in 1991 when population density was very high and (iii) 1-year-old kleptogamic males with small body size which possess neither secondary sexual organs nor a testicular gland, although their testes are functional and hyperdeveloped (up to 10.5% of carcass weight). The percentage of kleptogamic males was fairly stable in the population (from 7.9 to 10.0%) and highly variable in their age class (from 8.5 to 51.3%). It is suggested that kleptogamy is a conditional strategy adopted by smaller males. 相似文献
10.
Mona El Agoze Marylène Poirié Georges Périquet 《Entomologia Experimentalis et Applicata》1995,75(3):251-255
In most insect species where double matings occur, sperm from the second male preferentially fertilize subsequent eggs. However,
we demonstrate here that, as already shown for some other hymenopteran species, this is not the case in the ichneumonid waspDiadromus pulchellus (Wesmeal): sperm from the first male usually father all the female progeny. This precedence of the first male sperm is also
observed in double matings involving an haploid male and a diploid sterile male, whichever is the first mating male. We discuss
the consequences of this phenomenon from an evolutionary point of view. 相似文献