Widowhood, illegitimacy, marital reproduction and female longevity in a rural Spanish population

Using data from parish and civil registers in a rural community in northwest Spain (Los Nogales), family reconstitution provided 1502 complete reproductive histories, of which 584 corresponded to first marriages of women dying after their 50th birthday. A homogeneous sample consisting of women married in the period 1877–1899 (N = 311) provided information concerning their reproductive performance, including ages at first and last maternity and number of children born alive and surviving, which was related to the mother's post-menopausal longevity, also considering premarital fertility and her marital status (widow/married). The results obtained indicate that mothers with a lower proportion of children dying before the first birthday and the age of 15 (mainly males) have a greater post-reproductive longevity. Moreover, women with a more protracted end to their reproductive period and greater fertility live for more years beyond their 50th birthday. These results do not prove a causality between maternal longevity and more successful reproduction; instead, they are indicative of a holistic condition of health. A wide spectrum of favorable biological and environmental factors will have positive consequences for a woman's life trajectory, affecting both her reproductive performance and her own likelihood of surviving.     

Leaf longevity in evergreen shrubs: variation within and among European species

Summary Leaf longevities were determined for 16 species of evergreen shurbs (Ericaceae and Empetraceae) at different habitats at three latitudes (c. 47°, 55–58° and 68°N) in central and north Europe to determine whether any general trends exist in variation in leaf longevity within and among species. Among these species and sites, mean leaf longevity varied between 1.4 and 3.8 seasons, which is similar to the values reported for other evergreen shrubs, but shorter than for many evergreen conifers. Consistent differences in leaf longevity were found when comparing latitudes (ignoring altitude and habitat type): longevities were longer at 68°N than at the two lower latitudes. No consistent trends were found among species within altitudes.     

Haplotype and multipoint linkage analysis in Finnish choroideremia families

Summary Multipoint linkage analysis of choroideremia (TCD) and seven X chromosomal restriction fragment length polymorphisms (RFLPs) was carried out in 18 Finnish TCD families. The data place TCD distal to PGK and DXS72, very close to DXYS1 and DXYS5 (Zmax = 24 at = 0) and proximal to DXYS4 and DXYS12. This agrees with the data obtained from other linkage studies and from physical mapping. All the TCD males and carrier females studied have the same DXYS1 allele in coupling with TCD. In Northeastern Finland, 66/69 chromosomes carrying TCD had the same haplotype at loci DXS72, DXYS1, DXYS4, and DXYS12. The same haplotype is seen in only 15/99 chromosomes not carrying TCD. Moreover, in 71/104 non-TCD chromosomes, the haplotype at six marker loci is different from those seen in any of the 76 TCD chromosomes. This supports the previously described hypothesis that the large Northern Finnish choroideremia pedigrees, comprising a total of over 80 living patients representing more than a fifth of all TCD patients described worldwide, carry the same mutation. These linkage and haplotype data provide improved opportunities for prenatal diagnosis based on RFLP studies.     

A tradeoff between reproduction and growth in contemporary Finnish women

Women have been suggested to trade growth in height for reproduction, as an earlier age at menarche and first birth seem to be related to shorter adult stature. Although women likely accrue fitness benefits by maturing and starting reproduction at young age, short adult stature may be selected against by natural and sexual selection later in their life. We studied how age at menarche and first reproduction affected adult height and whether adult height in turn was related to lifetime reproductive success in Finnish women born 1946–1958. Our results show that a delay of 1 year in age at menarche and first reproduction was related to a 0.43- and 0.20-cm increase in adult height, respectively. The sex of the first-born offspring was not related to adult height. Moreover, women gained fitness benefits by starting reproduction early but not by growing tall. These findings among Finnish women are thus compatible with tradeoffs between reproduction and growth, by showing a compromised adult height at the cost of early age at menarche and first birth. However, in these women, natural selection favored those women who traded their stature for young motherhood.     

Effect of food type and concentration on the survival,longevity, and reproduction of Daphnia magna

The freshwater microalgae Ankistrodesmus falcatus and Scenedesmus incrassatulus, at three concentrations (6, 12 and 18 mg l⁻¹ t, dry weight), were tested as diets for Daphnia magna cultured in reconstituted hard water, at 19 ± 1 °C. Effects on survival, and reproductive characteristics were evaluated during a complete life-cycle. Test animals fed with the highest food concentration had the lowest survival, longevity, number of clutches, and average inter-brood times, but the total offspring was similar to that obtained with the lowest food concentration, for the same species of alga. Average longevity ranged from 40 to 85 days, with a minimum of 24 and a maximum of 119 days. The average inter-brood time ranged from 4.2 to 5.8 days, the highest values being observed at the lowest food concentration. The average total offspring was maximum for the intermediate concentrations of both algae. The maximum number of clutches ranged from 9 to 23, with the lowest values being observed at the highest food concentration. Even though both microalgae had similar effects on survival and reproduction, and the greatest differences observed were related to food concentration, it seems that S. incrassalulus is a comparatively better food for D. magna. The most suitable food level should be determined prior to carrying out chronic bioassays, and it is also an important factor in cultures for obtaining neonates for toxicological tests.     

Physiological trade-offs between reproduction,flight capability and longevity in a wing-dimorphic cricket,Modicogryllus confirmatus

Physiological and morphological comparisons were made between the short-winged (SW) and long-winged (LW) morphs of a cricket, Modicogryllus confirmatus, to determine the cost of the flight capacity and the physiological mechanisms underlying trade-offs between different life history traits related to migration and reproduction. Both wingmorphs grew at a similar rate and no consistent correlation was found between nymphal development and adult body size. The metathoracic muscles at adult emergence represented 4.2% of the wet body weight in the SW morph and 10.5% in the LW morph. Fat content of the body at adult emergence was positively correlated to dry body weight, but no significant difference was found in mean fat content between the two wingmorphs or between sexes after body weight was adjusted. SW females fed ad libitum produced significantly more eggs than LW females during the first 20days of adult life. Egg production was not correlated to either body size or the duration of nymphal development. LW adults lived longer than SW ones when kept with water alone or when given various amounts of food on day 1 and otherwise kept with water alone. In females, a highly significant correlation was found between longevity and egg production, indicating the presence of a trade-off. LW females mainly allocated the energy from food to flight muscle development and general maintenance of the body rather than to egg production, whereas SW females used it for egg production and longevity. LW females that had been de-alated at adult emergence histolyzed the flight muscle and used the energy from food for egg production almost exclusively. These results suggest that energy allocation and trade-offs after adult emergence may play crucial roles in the functional differentiation of the two wingmorphs.     

Parental investment, late reproduction, and increased reserve capacity are associated with longevity in humans

Throughout the living world trade-offs between reproductive success and longevity have been observed. In general, two extremes of life history patterning are reported, r- and K-selected species. The latter tend toward larger body sizes, few offspring from any one pregnancy, few offspring over the female reproductive span, longer life spans, and greater parental investment (PI: all efforts and expenses associated with the production, gestation, post-natal care, feeding, and protection of young) (e.g., whales, elephants, hominids). r-selected species tend toward smaller body size, multiple births/litters per pregnancy, female production of many gametes and offspring over the life span, and low levels of PI (e.g., most plants, insects, mice). These differences have significant influences on physiological variation among human populations.Across human samples, reproductive success (RS: the number of offspring successfully birthed and reared to reproductive age) has been reported to vary positively, negatively, and not at all with longevity of women. This complexity may be in part due to the fact that both early-life and late-life fecundity are associated with longevity in women, while total parity seems a poor gauge of female longevity in humankind. Large variations in associations of RS with longevity in women suggest that multiple factors may confound this association. One confounding factor is that among women, RS is largely determined not by fecundity, but by the quality of PI available to offspring. Among modern humans, PI is more complex, longer lasting (both relatively and absolutely), and extensive than for any other mammal. This suggests that modern human life history is a reflection of the co-evolution of longevity and extensive PI as part of our species' biocultural evolution. The need for long-term PI has greatly shaped human physiological variation and patterns of longevity.     

Determination of age, longevity and age at reproduction of the frogMicrohyla ornata by skeletochronology

Skeletochronological estimation of age, longevity, age at sexual maturity and breeding of Microhyla ornata was done. Frogs (n=62) were collected locally in August (rainy season) 1997 and brought to the laboratory. Body mass and snout-vent-length (SVL) of each frog was recorded; the 4th toe of both the hind limbs was clipped under anaesthesia, fixed in 10% formalin, demineralized in 5% nitric acid and processed for histology. Limb bones (femur, humerus, tibiofibula and radioulna) of 6 large sized frogs were also processed for skeletochronology in order to study the rate of resorption. Gonads of 25 frogs (belonging to different body size ranges) were processed for histology in order to ascertain the gametogenic status of individual frogs. One to four growth rings consisting of growth zones and lines of arrested growth (LAGs) were noticed in frogs of different body sizes; the number of LAGs remained identical in all the limb bones and phalanges in 5 out of 6 frogs. Back calculation indicated that the resorption rate is very low in this frog. Male frogs possessed sperm bundles in seminiferous tubules in the 1st year, while females showed yolky follicles in the ovary in the 2nd year. Frogs found in amplexus were 3 5 years old. The results suggest that this frog may live for a maximum of 5 years in the natural population.     

Familial amyloidosis, Finnish type: G654----a mutation of the gelsolin gene in Finnish families and an unrelated American family.

The Finnish type of familial amyloid polyneuropathy (FAF) is an autosomal dominant form of systemic amyloidosis caused by a mutation in the gelsolin gene. The mutation leads to the expression of amyloidogenic mutant Asp187----Asn gelsolin, an actin-modulating protein. We previously developed a DNA test based on amplification by the polymerase chain reaction followed by allele-specific oligonucleotide hybridization that identifies the base substitution adenine for guanine at nucleotide 654 in the gelsolin gene causing the disease. We show here that the same mutation is present in members of six apparently unrelated Finnish families and in a member of an unrelated American family. These results, taken together with previously published findings in nine additional Finnish families and another unrelated American family, indicate that most, perhaps all, FAF patients in Finland and possibly worldwide carry the same mutation. We suggest two alternative explanations: (i) the mutation arose in a very early common ancestor or (ii) the Asn187 mutation is particularly, perhaps uniquely, amyloidogenic.     

Recycling,reproduction, and life's origins

Kinetic considerations make it most improbable that any reproducing system could arise spontaneously in a prebiotic soup containing a large variety of organic molecules, as commonly postulated. This batch process can be contrasted with a completely recycling network of reactions maintained by an influx of energy. So long as the network includes at least two bimolecular reactions it is likely to support pathways for chemical reproduction. However, such reproducing systems will be simple in both kinetic and structural terms. Subsequent evolution will lead to much more complex reproducing structures although the kinetic complexities, measuring the varieties of reactions between these structures and their media, will remain relatively simple.     

Behavior,net reproduction,longevity, and mummy-stage survival ofAphidius matricariae [Hym. Aphidiidae]

The courtship, mating and ovipositional behavior ofA. matricariae Haliday were studied. UsingMyzus persicae (Sulzer) as the host, the production of progeny per female parasite and survival from mummy stage to the adult were studied at constant temperatures of 10°, 12.8°, 15.6°, 18.3°, 21°, 24°, 26.7°, 29.5° and 32°C. The longevity of male and female parasites was determined at temperatures of 7°, 10°, 15.6°, 21°, 26.7°, 29.5° and 32°C. The greatest number of progeny (392) was produced at 21°C. The optimal temperatures for production of progeny and survival of the parasites during the mummy stage were from 12.8°C to 21°C. The longevity of male and female adult parasites decreased as temperatures increased and male parasites lived significantly (P<0.05) longer than females at 10° and 15.6°C.     

The effects of reproduction on longevity and fertility in male Drosophila melanogaster

We examined the effect of reproduction on subsequent survival and fecundity of male Drosophila melanogaster by reversing the reproductive status of individuals part-way through life. Reproduction had a much more marked effect on fertility than survival: males with a history of reproduction showed complete sterility at a time when upwards of 80% of their cohort were still alive. Analyses of survival rates alone gave a misleading measure of the impact of ageing. Sterility appeared to be attributable mainly to a reduction in sperm count. Early reproduction caused permanent, irreversible damage to both survival and fecundity, with risk playing an apparently minor role. Individual differences in frailty appeared to be of little consequence for the interpretation of these reversal experiments, although its possible occurrence made definite detection of risk difficult.     

Tumour incidence, growth, reproduction and longevity in female C3H mice fed polyunsaturated ruminant-derived foodstuffs

Earlier studies with the random-bred Quackenbush mouse strain showed that human-type diets based on linoleic acid-enriched foodstuffs derived from ruminants fed protected polyunsaturated oils have no detrimental effects on growth, reproduction or longevity. Tumour incidence and time of onset of tumour development have now been studied in the inbred, tumour-prone mouse strain C3H, in addition to growth, reproduction and longevity. Mice were fed a polyunsaturated human diet, a conventional human diet, or mouse cubes. The results with C3H mice tended to confirm those with Quackenbush strain mice-growth rates and reproductive productivities were very similar in the two groups eating human diets. Mice on the conventional human diet tended to survive better to about 60 weeks of age than mice on the polyunsaturated diet or the cube diet, after which the mortality rates of the mice on the three diets were similar. The degree of unsaturation of the dietary fat had no significant effect on the incidence of tumours. The tumour incidence was about 40% which, taken in conjunction with the average age of onset (about 80 weeks), suggested that the NIV virus rather than the MMTV virus was responsible. It would appear that the high-fat human diets had no effect on the incidence of mammary tumours caused by this virus.     

Whole-genome SNP association analysis of reproduction traits in the Finnish Landrace pig breed

Background

Good genetic progress for pig reproduction traits has been achieved using a quantitative genetics-based multi-trait BLUP evaluation system. At present, whole-genome single nucleotide polymorphisms (SNP) panels provide a new tool for pig selection. The purpose of this study was to identify SNP associated with reproduction traits in the Finnish Landrace pig breed using the Illumina PorcineSNP60 BeadChip.

Methods

Association of each SNP with different traits was tested with a weighted linear model, using SNP genotype as a covariate and animal as a random variable. Deregressed estimated breeding values of the progeny tested boars were used as the dependent variable and weights were based on their reliabilities. Statistical significance of the associations was based on Bonferroni-corrected P-values.

Results

Deregressed estimated breeding values were available for 328 genotyped boars. Of the 62 163 SNP in the chip, 57 868 SNP had a call rate > 0.9 and 7 632 SNP were monomorphic. Statistically significant results (P-value < 2.0E-06) were obtained for total number of piglets born in first and later parities and piglet mortality between birth and weaning in later parity, and suggestive associations (P-value < 4.0E-06) for piglet mortality between birth and weaning in first parity, number of stillborn piglets in later parity, first farrowing interval and second farrowing interval. Two of the statistically significant regions for total number of piglets born in first and later parities are located on chromosome 9 around 95 and 79 Mb. The estimated SNP effect in these regions was approximately one piglet between the two homozygote classes. By combining the two most significant SNP in these regions, favourable double homozygote animals are expected to have 1.3 piglets (P-value = 1.69E-08) more than unfavourable double homozygote animals. A region on chromosome 9 (66 Mb) was statistically significant for piglet mortality between birth and weaning in later parity (0.44 piglets between homozygotes, P-value = 6.94E-08).

Conclusions

Three separate regions on chromosome 9 gave significant results for litter size and pig mortality. The frequencies of favourable alleles of the significant SNP are moderate in the Finnish Landrace population and these SNP are thus valuable candidates for possible marker-assisted selection.     

营养物质和水分对韭菜迟眼蕈蚊成虫繁殖和寿命的影响

【目的】研究韭菜迟眼蕈蚊Bradysia odoriphaga成虫对营养物质的选择补充习性,找出对其产卵繁殖起重要作用的关键因子,为其有效防控提供依据。【方法】通过室内成虫单独配对试验,研究不同营养物质(花粉、蜂蜜、维生素、糖、醋、酒)和水分对韭菜迟眼蕈蚊成虫繁殖和寿命的影响。【结果】随着花粉、蜂蜜和维生素浓度的增加,成虫的繁殖力下降;糖醋酒液单一成分和混合液对成虫繁殖和寿命的影响与水分相近;补充供试营养物质和水分对韭菜迟眼蕈蚊的繁殖力均明显高于干燥对照。补充水分的成虫繁殖力最高,产卵率超过70%,单雌平均产卵量达70粒,雌雄成虫寿命最长均超过3 d。土壤湿度对产卵有显著影响,土壤相对湿度为40%和50%时,成虫的落卵率超过25%,落卵量大于480粒,显著高于其它湿度(P<0.05)。【结论】水分是影响韭菜迟眼蕈蚊成虫繁殖和寿命的关键因子,供试的营养物质对韭菜迟眼蕈蚊繁殖没有促进作用,因此在韭菜迟眼蕈蚊成虫盛发期可以通过控制田间土壤湿度来影响韭菜迟眼蕈蚊繁殖。     

An insulin-like signaling pathway affects both longevity and reproduction in Caenorhabditis elegans.

Mutations in daf-2 and age-1 cause a dramatic increase in longevity as well as developmental arrest at the dauer diapause stage in Caenorhabditis elegans. daf-2 and age-1 encode components of an insulin-like signaling pathway. Both daf-2 and age-1 act at a similar point in the genetic epistasis pathway for dauer arrest and longevity and regulate the activity of the daf-16 gene. Mutations in daf-16 cause a dauer-defective phenotype and are epistatic to the diapause arrest and life span extension phenotypes of daf-2 and age-1 mutants. Here we show that mutations in this pathway also affect fertility and embryonic development. Weak daf-2 alleles, and maternally rescued age-1 alleles that cause life span extension but do not arrest at the dauer stage, also reduce fertility and viability. We find that age-1(hx546) has reduced both maternal and zygotic age-1 activity. daf-16 mutations suppress all of the daf-2 and age-1 phenotypes, including dauer arrest, life span extension, reduced fertility, and viability defects. These data show that insulin signaling, mediated by DAF-2 through the AGE-1 phosphatidylinositol-3-OH kinase, regulates reproduction and embryonic development, as well as dauer diapause and life span, and that DAF-16 transduces these signals. The regulation of fertility, life span, and metabolism by an insulin-like signaling pathway is similar to the endocrine regulation of metabolism and fertility by mammalian insulin signaling.