Glossina palpalis fuscipes Newst. in Lake-side and in Riverine Forest

The ecology of the <i>fusca</i> group of tsetse flies (<i>Glossina</i>) in southern Nigeria

The methods typically developed in income inequality and poverty research are employed to observe changes in life spans distribution in 35 developed countries. The analyses are performed at two levels, using the same methods when possible: i/ taking the countries as the units with a mean length of life being a single parameter representing the distribution, ii/ utilizing the country life tables (taking people as the units) in order to compare other than mean length of life attributes of mortality distribution. Increasing divergence in the mean length of life across the countries is due to growing distance of the countries below the median, mainly the post-communist ones, to the upper half. The comparisons of the within-country distributions of ages at death by means of the Kullback-Leibler divergence provides similar results. However, poverty and inequality indices calculated at this level yield opposite conclusions. Hence, most of the between-country variation might be attributed to the variation in the mean length of life while the changes in within-country inequality reduced this effect. At the same time, huge alterations in the within-country mortality rankings can be observed. Australia, Japan, Taiwan, Austria and Luxembourg may be said to be the “winners” while most of the post-communist countries are among the “losers”.

The methods typically developed in income inequality and poverty research are employed to observe changes in life spans distribution in 35 developed countries. The analyses are performed at two levels, using the same methods when possible: i/ taking the countries as the units with a mean length of life being a single parameter representing the distribution, ii/ utilizing the country life tables (taking people as the units) in order to compare other than mean length of life attributes of mortality distribution. Increasing divergence in the mean length of life across the countries is due to growing distance of the countries below the median, mainly the post-communist ones, to the upper half. The comparisons of the within-country distributions of ages at death by means of the Kullback-Leibler divergence provides similar results. However, poverty and inequality indices calculated at this level yield opposite conclusions. Hence, most of the between-country variation might be attributed to the variation in the mean length of life while the changes in within-country inequality reduced this effect. At the same time, huge alterations in the within-country mortality rankings can be observed. Australia, Japan, Taiwan, Austria and Luxembourg may be said to be the “winners” while most of the post-communist countries are among the “losers”.

Newly emerged adults of the hymenopterous parasite Macrocentrus ancylivorus Roh. were fed for their entire adult lifetime on a diet consisting solely of a solution, of one sugar only, of specified concentration. Sexes were kept distinct. Temperature was constant at 26.5 °C. throughout the experiments. Dextrose, levulose, galactose, maltose, sucrose, and lactose were tested at seven concentrations ranging from 0.1% to 40%. The mean length of life on lactose at any concentration was only slightly longer than on water. Survival on galactose was moderate. Survival was satisfactory on all the remaining four sugars. The mean length of life on these sugars increased rapidly as concentration was increased and was optimal at 5%. Above this concentration survival declined, especially at high concentrations of 20% and 40%; however, at the latter concentrations survival was greater than at concentrations of 2.5%. Survival on a 10% honey solution was not as great as on solutions of the four sugars at the same concentration. The mean length of life of males generally was slightly less than that of females.

Abstract. How much temporal variation in recruitment, mortality and change in size class occurs in the sapling layer of mature temperate forests in the absence of large‐scale exogenous disturbance? Using 15 years of data from a flood‐plain forest in Big Thicket National Preserve, we found that year‐to‐year variation in demographic parameters was greater than we originally expected. Death rates were generally more variable than recruitment rates, and were much more variable for large saplings than for small ones. Small saplings of the 10 most common species had at least one year when they experienced two to eight times their long‐term mean recruitment and death rates. Large saplings had at least one year when they experienced three to 10 times their long‐term mean death rates and at least one year with two to seven times the long‐term mean recruitment rate. Temporal patterns in sapling death rates were related to flooding patterns, while temporal patterns in recruitment were related to the Palmer Drought Severity Index, an indicator of drought severity and soil moisture availability. We also identified apparently synchronous patterns of demographic response among less flood‐tolerant species which differed from the responses of more flood‐tolerant species. We demonstrated the effects of both climatic variation and light variation in affecting stand‐wide sapling demographics in a forest where canopy gaps are important for regeneration, and where chronic understorey disturbance favours growth over survivorship as a sapling strategy.

Sweep-net and sticky-trap data were used to examine the influence of time of day (morning, afternoon, evening), trapping location (pasture, bog, fen, regrowth, and mature forest), and meteorological factors (wind, temperature, saturation deficit, and light) on adult female fly catch for three species (species complex) of black flies — Simulium truncatum/venustum complex, Prosimulium mixtum, and Stegopterna mutata (triploid). Wind speed, light, temperature, saturation deficit, and time of day were all shown to have a significant effect on mean catch, although effects varied among species. After accounting for weather and time, trap location was shown to have a significant effect on mean catch. The effect of site on the mean fly catch of S. truncatum/venustum complex varied with season (June to July), which may have resulted from a seasonal shift in sibling-species composition. Mean catches of P. mixtum and St. mutata were lowest in traps located in open habitats.

From Leaf to Topsoil, a Semi-quantitative Assessment of the Organic Matter Variations in Riparian Forests on a Lake Shore

Paddlefish Polyodon spathula from the 1985-1986 commercial harvest from Kentucky Lake, Kentucky-Tennessee, were weighed and their lengths from eye to fork of the tail were measured. During 52 observed trips, commercial fishermen harvested 702 paddlefish (4,002 kg) with 788 gill-net-nights of effort. However, the harvest was a disappointment to the fishermen because catch rates were low, and only 15 gravid females were included in the observed catch. The paddlefish that were aged from dentary bones (N = 362) were 2-16 years old. The age-length equation was a log10 transformation of a linear relationship, and the weight-length equation was a log10 transformation of an algebraic relationship. There were no significant differences in backcalculated growth between sexes. Growth was slower than reported for most other populations. The sex ratio was 1:1, and the youngest sexually mature fish were 6 and 8 years old for males and females, respectively. The age of recruitment and annual mortality were 8 years and 61 % for males and 9 years and 60% for females. Overall recruitment age was 9 years, and annual mortality was 69%. The mean length and weight of paddlefish in the commercial catch was 691 mm and 5.7 kg, the mean commercial catch was 57.1 kg and 13.5 fish per night, and mean catch per unit effort (CPUE) was 3.77 kg/91.4-m net per night. Mean size offish, catch rate, and CPUE were highest during the spawning run. A gill-net mesh size of 127 mm was most popular and caught larger fish. The Kentucky Lake paddlefish population shows several signs of overexploitation: high mortality for several years, a comparatively young population, and a low number of spawners. Therefore, we recommend the creation of a spawning refuge, implementation of a maximum gill-net mesh size, and an increase in commercial fishing license fees for paddlefish management.

Based on a computational analysis of a large dataset, this study explores if there is a significant longevity effect of intercessory prayer for a named individual’s well-being, if he receives a very high number of prayers per annum for an extended period. We relied on an observational cohort study, based on data from 1988 to 2018, including 857 Roman Catholic bishops, 500 Catholic priests, and 3038 male academics from six countries. We measured the covariance of the mean length of life, controlled for nationality. It was found that there is a main effect for occupation F(2, 4391) = 4.07, p = 0.017, ηp2 = 0.002, with pairwise comparisons indicating significant differences between the mean life duration of bishops (M = 30,489) and of priests (M = 29,894), but none between the academic teachers (M = 30,147) and either of the other groups. A comparison analysis between bishops from the largest and the smallest dioceses showed no significant difference t(67.31) = 1.61, p = 0.11. The first analysis proved that bishops live longer than priests, but due to a marginal effect size this result should be treated with caution. No difference was found between the mean length of life of bishops from the largest and the smallest dioceses.

MEAN LENGTH OF LIFE.

Reproductive and life-history parameters of the parasitoid Leptopilina boulardi (Barbotin et al.) were experimentally determined. Two cohorts of wasps originally reared on Drosophila simulans (Sturtevant) were used, one exposed to a laboratory strain of D. melanogaster (Meigen), the other a sympatrically collected strain of D. simulans. Parasitoids presented with D. melanogaster larvae produced significantly more male (163.8 ± 10.2), female (129.6 ± 9.8), and total progeny (293.4 ± 10.1), and exhibited a significantly higher sex ratio (0.55 ± 0.03) than did those presented with D. simulans larvae (90.9 ± 5.0, 93.5 ± 5.0, 184.4 ± 5.2, and 0.49 ± 0.02, respectively). These data confirm previous estimates of host species suitability. Mean length of life and schedules of progeny production did not differ significantly between groups. Both cohorts exhibited similar fertility distributions with peaks in oviposition rate occurring on the second day of host exposure. This peak was followed by a sharp decline, which attenuated slowly during a long period of post-reproductive survival—9.8 ±0.7 days for the cohort presented with D. melanogaster larvae; 8.4 ± 0.6 days for the cohort presented with D. simulans larvae.

1. With unfed 1st instars the relation between mean length of life and saturation deficit at constant temperatures between 7 and 15° C. at relative humidities between 7 and 90% is hyperbolic. The relationship becomes more linear at higher temperatures.At constant saturation deficits insects live longer at 15° C. than at lower temperatures. Longevity also decreases with rise of temperature above approximately 15° C.2. In general, the longevity curves, except for those at temperatures below 15° C., bear a very similar relation to saturation deficit and to each other as the reciprocal curves for rate of water-loss at the different temperatures.The influence of climatic factors on longevity at constant temperatures is discussed at length and it is concluded that over much of the temperature and humidity range survival time is limited by water-loss. At the higher humidities it is thought that either food, or perhaps an excessive accumulation of water within the insect, limits survival and causes a departure from the hyperbolic relation of longevity to saturation deficit.3. The effects on longevity of a single meal are discussed. The principal effect of a blood meal is to increase the time of survival. But the factors which limit survival at different humidities appear to be the same as with unfed bugs, except at high humidities below about 15° C.4.Mellanby's data on the rate of water-loss from fasting adult bed-bugs is analysed. It is found that the rate of water-loss is directly proportional to saturation deficit at constant temperatures between 8 and 37° C. and between 0 and 90%r.h. Although the rate may always be directly proportional to saturation deficit, the expressionis not always constant.Rate =K+b(saturation deficit), whereKvaries with temperature andbremains constant.5. Longevity in relation to host blood is discussed. Rabbit blood appears to be slightly less favourable to survival than human blood.6. If bugs are allowed to feed to repletion, longevity is not correlated with the size of the meal, nor with the weight of the unfed insect.Virgin females live longer than mated ones, but no effects of mating on survival were noticed with males. Mated males tend to outlive mated females except at very low temperatures: virgin females live longer than unmated males.7. The results of other workers and the possible causes of some discrepancies are discussed.8. The maximum survival times of bugs are listed. Adults and 5th instars live longer than other stages. In a house which has remained empty for a long time it is probable that 5th instars and adults, particularly unmated female adults, would predominate in the population.The longest observed survival was between 562 and 572 days.

Koivisto, K. and Portin, P. 1987. Induction of mutations which shorten the adult life span in Drosophila melanogaster.- Hereditas 106: 83–87. Lund, Sweden. ISSN 0018–0661. Received April 10, 1986 Yellow (y, 1 - 0.0) males of Drosophila melanogaster were treated with ethylmethane sulphonate (EMS). The males were crossed with Muller-5 (Basc) females. Of the 252 chromosomes tested 127 (50.4%) contained a lethal mutation, but we were also able to extract 51 homozygous yellow stocks which contained a EMS-treated X chromosome. 13 of the stocks (25.5 %) contained a mortality mutation (mor (1)), i.e., the duration of adult life in these stocks was considerably decreased as indicated by the mean length of life and survival curves. Furthermore, in one stock the adult life span was significantly increased. In each case of the mortality mutations the mean life span and the survival curve were different, indicating different action of the mutations. However, it was possible to group the mortality mutations into three major classes each characterized by similar typical survival curves. The different action of the mortality mutations, however, suggests that they are mutations of different genes. Therefore, and on the basis of the frequency of mortality mutations it is concluded that many genes can mutate to mortality mutations, tentatively suggesting that there are many genes which affect ageing in a non-specific way.

The laboratory rearing of all stages in the life-history of the Wheat Bulb Fly, Leptohylemyia coarctata, (Fall.), is described. The object of this work was to provide suitable material, in particular eggs and larvae, for insecticide experiments. Details of a container suitable for ovipositing adults are given. Several diets for the adults were compared and it was found that the greatest number of eggs was produced when the flies were fed on beef blood and a mixture of sweetened condensed milk and honey. Females were found to lay up to 244 eggs each; egg-laying commences 9–15 days after emergence and continues almost as long as the females live, but reaches a peak 3–5 weeks after emergence. Some females survived from late June until early November. In a small laboratory population, the average number of eggs laid by each female was 29·9 and mean length of life was 26·3 days for males and 41·6 days for females.The eggs have a long obligatory diapause period. They have no effective water-proofing mechanism, but can recover from considerable temporary desiccation. A method of storage during diapause is described. The eggs normally hatch in late January or early February, but hatching can be delayed until much later in the year by storage below 0°C.The effects of temperature on larval and pupal development are described. Larvae will grow at 20°C., but pupating larvae or young pupae are rendered sterile unless kept at temperatures of 15°C. or below. It is shown how a combination of delayed hatching and rapid larval and pupal development can produce fertile flies at unusual times of the year in the laboratory. It is suggested that this may make it possible to produce young larvae in the autumn for insecticide experiments.In conclusion, some parasites and predators encountered in the field and the laboratory are mentioned.

SummaryWorkers in the colony under observation were classified into three groups according to behaviour: foragers, house-bees, foragers, house-bees. Measurement (of wing length) showed that house-bees and foragers/house-bees were smaller than most foragers. The mean length of life was 72·6, 69·7 and 36·4 days for house-bees, foragers/house-bees and foragers respectively. The survival curves were convex for house-bees and foragers/house-bees and concave for foragers.