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Same Colony (same + colony)
Selected AbstractsMating compatibility, life-history traits, and RAPD-PCR variation in Bemisia tabaci associated with the cassava mosaic disease pandemic in East AfricaENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 1 2001M.N. Maruthi Abstract The pandemic of a severe form of cassava mosaic virus disease (CMVD) in East Africa is associated with abnormally high numbers of its whitefly vector, Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae). To determine whether a novel B. tabaci biotype was associated with the CMVD pandemic, reproductive compatibility, fecundity, nymphal development, and random amplified polymorphic DNA (RAPD) variability were examined in, and between, B. tabaci colonies collected from within the CMVD pandemic and non-pandemic zone in Uganda. In a series of reciprocal crosses carried out over two generations among the six CMVD pandemic and four non-pandemic zone cassava B. tabaci colonies, there was no evidence of mating incompatibility. All the crosses produced both female and male progeny in the F1 and F2 generations, which in a haplo-diploid species such as B. tabaci indicates successful mating. There also were no significant differences between the sex ratios for the pooled data of experimental crosses, between individuals from two different colonies and control crosses between individuals from the same colony. Only one instance of mating incompatibility occurred in a control cross between cassava B. tabaci from Uganda and cotton B. tabaci from India. Measures of fecundity of the pandemic and non-pandemic zone B. tabaci on four cassava varieties showed no significant differences in their fecundity, nymphal development or numbers surviving to adult eclosion. Cluster analysis of 26 RAPD bands using six 10-mer primers was concordant with the mating results, grouping the pandemic and non-pandemic zone colonies into a single large group, also including a B. tabaci colony collected from cassava in Tanzania. These results suggest that it is unlikely that the severe CMVD pandemic in East Africa is associated with a novel and reproductively isolated B. tabaci biotype. [source] Effects of inbreeding on immune response and body size in a social insect, Bombus terrestrisFUNCTIONAL ECOLOGY, Issue 5 2003C. U. Gerloff Summary 1Inbreeding can negatively affect various fitness components. Here we examine how immune response and body size of a social insect are affected by inbreeding, sex and ploidy. 2In the bumble-bee, Bombus terrestris (L.), the offspring of colonies resulting from brother,sister matings were compared with that of outbred colonies. Immune response was measured as the degree of encapsulation of a novel antigen, body size as the length of the radial cell in the forewings. 3Inbreeding affected neither immune response nor body size in either workers or haploid males under laboratory conditions. However, fitness characteristics varied significantly among maternal families and colonies. The lack of detectable inbreeding depression for two fitness components might help explain why B. terrestris is a good colonizer in nature. 4In addition, sex and ploidy strongly affected the fitness components studied: diploid males had a significantly lower immune response than haploid males, who in turn had a significantly lower immune response than workers of the same colony. The body size of diploid males was intermediate between the body size of workers and haploid males. [source] Social structure of a polygynous tent-making bat, Cynopterus sphinx (Megachiroptera)JOURNAL OF ZOOLOGY, Issue 2 2000Jay F. Storz Abstract The social structure of an Old World tent-making bat Cynopterus sphinx (Megachiroptera), was investigated in western India. A combination of census and mark,recapture data over 2 years (1996,98) was used to infer the form of the mating system, compositional stability of social groups and mode of new social group formation. The breeding population of C. sphinx was subdivided into diurnal roosting colonies, each of which contained one to five discrete roosting groups and often one or more solitary bats in adjacent roosts. Bats most frequently roosted in stem tents constructed in the flower/fruit clusters of the kitul palm Caryota urens. Temporal variation in social structure was assessed using visual census data for a subset of the study population over 3 years (1995,98) spanning six consecutive reproductive periods. The sex and age composition of diurnal roosting groups indicated a polygynous harem-forming mode of social organization, as groups invariably contained a single adult male, 1,37 reproductive females and their dependent young (n= 33 harems). Harem size averaged 6.1 adults in the wet season (n= 19, sd= 3.5) and 13.6 adults in the dry season (n= 14, sd= 8.5). The same harem social configuration was maintained year-round, despite a high degree of synchrony and seasonality in the timing of reproduction. Juveniles of both sexes dispersed after weaning and sexually immature bats were never present in harems at the time of parturition. Adult females often remained associated as roostmates from one parturition period to the next, and group cohesion was unaffected by turnover of harem males. Adult females frequently transferred among roosts within the same colony, and harems underwent periodic fissions and fusions. The founding of new harems most often resulted from the fissioning of previously cohesive harems within the same colony. However, some harems contained disproportionate numbers of yearling females, indicating that new groups are also founded by nulliparous females of the same age cohort. A significant degree of heterogeneity in age composition among harems was revealed in the 1998 dry season, but was unrelated to age-stratification of tent roosts. Although formation of new harems may be non-random with respect to age composition of the founders, founding events are not restricted to newly created tents and often involve recolonization of previously occupied roosts. [source] Cuticular hydrocarbons in a termite: phenotypes and a neighbour,stranger effectPHYSIOLOGICAL ENTOMOLOGY, Issue 3 2002Manfred Kaib Abstract The composition of cuticular hydrocarbons of different colonies of the fungus-growing termite Macrotermes falciger shows considerable intercolonial variation. Ordination, as well as cluster analyses, separate profiles into three distinct chemical phenotypes. Behavioural tests with major workers reveal no alarm behaviour or mortality in pairings of workers from the same colony but a full range from no alarm to overt aggression, with associated death, when individuals were paired from different colonies. The level of mortality increases with differences in the composition of cuticular hydrocarbons between colonies. However, no mortality occurs in pairings of individuals from neighbouring colonies belonging to different phenotypes. The data thus provide evidence for a ,neighbour,stranger' effect (so-called ,dear-enemy' phenomenon) in termites. [source] | ||||||||||