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Many Females (many + female)
Selected AbstractsCaptures of the olive fruit fly Bactrocera oleae on spheres of different coloursENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 2 2001Byron I. Katsoyannos Abstract Alighting and capture of wild olive fruit flies, Bactrocera oleae (Rossi) (Diptera, Tephritidae), on spheres of seven different colours was studied on Chios island, Greece. The 70-mm-diam plastic spheres, coated with adhesive, were suspended on olive trees. Yellow and orange spheres trapped the greatest number of males while red and black spheres trapped the greatest number of females. White and blue spheres were the least effective for both sexes. Peak captures occurred in the late afternoon and especially around sunset. Since mating takes place in the last hours of the photophase, the increased captures during that period may be related to the sexual behaviour of the fly. When red spheres were assessed against glass McPhail traps baited with 2% ammonium sulphate, which consist a standard tool for monitoring the olive fruit fly in Greece, there were no significant differences in male captures. However, spheres trapped almost three times as many females as McPhail traps. The possible mechanisms underlying colour discrimination, the motivation of alighting flies and the possible use of red spheres for monitoring and controlling B. oleae are discussed. [source] Effects of intensive harvesting on moose reproductionJOURNAL OF APPLIED ECOLOGY, Issue 3 2000Catherine Laurian Summary 1.,It has been hypothesized that a balanced adult sex ratio is necessary for the full participation of ungulate females in reproduction and therefore high productivity. We tested this general hypothesis by combining two complementary approaches. 2.,First, using telemetry (n = 60) and annual aerial censuses between 1995 and 1998, we compared two moose Alces alces populations in Quebec, Canada, one non-harvested and the other subject to intensive sport harvesting from the end of September to mid-October. We tested the following predictions for the harvested population: (i) females increase movements and home ranges during the mating period; (ii) the mating system is modified, with the appearance of groups of one male and many females; (iii) subadult males participate in reproduction; (iv) the mating period extends over two to three oestrus cycles; (v) the calving period extends over several months; and (vi) productivity declines. 3.,Daily movements and home range sizes during the mating period did not differ between harvested and non-harvested populations. Most groups observed were male,female pairs. Subadult males (1·5,2·5 years old) were only observed with females in the harvested population. Mating and calving periods did not differ between populations. The proportion of females that gave birth and the number of calves produced were also comparable in the two populations. 4.,Secondly, we also assessed the existence of a relationship between population productivity and percentage of males in various management units of the province of Quebec that were characterized by a wide range in sex ratios. Contrary to prediction (vi), the number of calves per 100 adult females was not related to the percentage of adult males in the population. 5.,The participation of young adult males (subadults) in reproduction in our harvested population may have compensated for the lower percentage of adult males, and thus productivity was unaffected. We therefore reject the hypothesis that intensive harvesting, at least at the level we observed, affects reproduction and population productivity. 6.,As there are some uncertainties regarding the long-term effects of high hunting pressure, however, managers should favour sex ratios close to levels observed in non-harvested populations. [source] Poisoning in Zimbabwe: a survey of eight major referral hospitalsJOURNAL OF APPLIED TOXICOLOGY, Issue 2 2002D. Tagwireyi Abstract A retrospective study of the pattern of poisoning cases admitted to eight major urban referral hospitals in Zimbabwe over a 2-year period (1998,1999 inclusive) was conducted to describe the pattern of poisoning at these centres. There were a total of 2764 hospital admissions due to poisoning, involving a total of 2846 toxic agents. Accidental poisoning (AP) and deliberate self-poisoning (DSP) accounted for 48.9% (1352 cases) and 41.3% (1142 cases), respectively. With AP, the highest number of cases (45.9%) occurred in children below the age of 5 years, with half of these due to chemicals, mainly paraffin. In the DSP group, however, more than 60% of all cases occurred in the 16,25-year age group. In addition, twice as many females as males were admitted for DSP compared with an overall male/female ratio of 1 : 1.2. Pesticides (31.4%) and pharmaceuticals (30.4%) were the most common groups of toxic agents responsible for the hospital admissions. Unknown toxins, natural toxins and pesticides showed the highest mortality rates (15.4%, 8.3% and 6.7%, respectively). Compared with the last major survey of poisoning in Zimbabwe, the pattern of poisoning at referral hospitals has changed over the last decade, with an increase in pesticide and pharmaceutical cases and a marked fall in cases of traditional medicine poisoning. Educational and legislative interventions may be required to address these changes. There is the need also to investigate further the high mortality rates associated with traditional medicine poisoning. Copyright © 2002 John Wiley & Sons, Ltd. [source] Caste fate conflict in swarm-founding social Hymenoptera: an inclusive fitness analysisJOURNAL OF EVOLUTIONARY BIOLOGY, Issue 4 2003T. Wenseleers Abstract A caste system in which females develop into morphologically distinct queens or workers has evolved independently in ants, wasps and bees. Although such reproductive division of labour may benefit the colony it is also a source of conflict because individual immature females can benefit from developing into a queen in order to gain greater direct reproduction. Here we present a formal inclusive fitness analysis of caste fate conflict appropriate for swarm-founding social Hymenoptera. Three major conclusions are reached: (1) when caste is self-determined, many females should selfishly choose to become queens and the resulting depletion of the workforce can substantially reduce colony productivity; (2) greater relatedness among colony members reduces this excess queen production; (3) if workers can prevent excess queen production at low cost by controlled feeding, a transition to nutritional caste determination should occur. These predictions generalize results derived earlier using an allele-frequency model [Behav. Ecol. Sociobiol. (2001) 50: 467] and are supported by observed levels of queen production in various taxa, especially stingless bees, where caste can be either individually or nutritionally controlled. [source] Changing patterns of coeliac serology requestsALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 10 2009K. E. EVANS Summary Background, Accurate serological tests have revolutionized the diagnosis of coeliac disease. Aim, To quantify the volume of coeliac serology requests at a district hospital over a decade, identify their origin, assess positivity rates and subsequent duodenal biopsy and histological confirmation rates. Methods, Details of patients in whom coeliac serology was requested from 1997 to 2006 were obtained from laboratory databases. The origins of request were categorized into gastroenterology, general practice, paediatrics and other specialities. Duplicate requests were excluded. Results, A total of 9976 serological tests were requested. Testing increased from 302 in 1997, to 1826 in 2006. In all, 66% of requests were in females. Tests in children accounted for 14,25% of each year's total. General practitioner requests increased from 3.3% in 1997 to 52% in 2006. The proportion of positive serological results fell from 5.7% in 1997 to 2.6% in 2006. Duodenal biopsies were performed in approximately 85% of seropositive patients in earlier years and approximately 75% of seropositive patients in later years. Most nonbiopsied seropositive patients had serology requested by general practitioners. Biopsies confirmed coeliac disease in 91% of seropositive patients. Conclusion, Increasingly, coeliac serological testing is requested by general practitioners. Twice as many females are tested. Increasing test numbers but diminishing positivity rates suggest testing is requested at lower symptom thresholds. Positive serological results are often not confirmed histologically. [source] | ||||||||||