Tribolium confusum responses to blends of cereal kernels and plant volatiles

In this study, we report on the behavioural responses of the Tribolium confusum to 6 blends of cereal volatiles. There were tested four doses (1 ng/min, 10 ng/min, 100 ng/min and 1000 ng/min in 50 μl of hexane applied on filter paper). A Y‐tube experiment revealed that T. confusum females and males were attracted to the blend 1, 4 and 5 at the concentrations between 1 and 10 ng/min. Confused T. confusum females and males were not attracted to any concentration of blend 2 and 3. Yet the beetle females and males were repelled by the highest concentrations (1000 ng/min) for all the blends tested and also by the concentration 100 ng/min of all the blends tested, except for blend 1 and 4. Females and males were also repelled by the three blend 6 concentrations tested (10, 100 and 1000 ng/min).     

Fluctuating thermal environments and time‐dependent effects on fruit fly egg‐hatching performance

Organismal performance in a changing environment is dependent on temporal patterns and duration of exposure to thermal variability. We experimentally assessed the time‐dependent effects of thermal variability (i.e., patterns of thermal exposure) on the hatching performance of Drosophila melanogaster. Flies were collected in central Chile and maintained for four generations in laboratory conditions. Fourth generation eggs were acclimated to different thermal fluctuation cycles until hatching occurred. Our results show that the frequency of extreme thermal events has a significant effect on hatching success. Eggs exposed to 24 hr cycles of thermal fluctuation had a higher proportion of eggs that hatched than those acclimated to shorter (6 and 12 hr) and longer cycles (48 hr). Furthermore, eggs subjected to frequent thermal fluctuations hatched earlier than those acclimated to less frequent thermal fluctuations. Overall, we show that, egg‐to‐adult viability is dependent on the pattern of thermal fluctuations experienced during ontogeny; thus, the pattern of thermal fluctuation experienced by flies has a significant and until now unappreciated impact on fitness.     

Getting to the core: Internal body temperatures help reveal the ecological function and thermal implications of the lions’ mane

It has been proposed that there is a thermal cost of the mane to male lions, potentially leading to increased body surface temperatures (T_s), increased sperm abnormalities, and to lower food intake during hot summer months. To test whether a mane imposes thermal costs on males, we measured core body temperature (T_b) continuously for approximately 1 year in 18 free‐living lions. There was no difference in the 24‐hr maximum T_b of males (n = 12) and females (n = 6), and males had a 24‐hr mean T_b that was 0.2 ± 0.1°C lower than females after correcting for seasonal effects. Although feeding on a particular day increased 24‐hr mean and 24‐hr maximum T_b, this phenomenon was true of both male and female lions, and females had higher 24‐hr mean and 24‐hr maximum T_b than males, on both days when lions did not feed, and on days when lions did feed. Twenty‐four‐hour T_b was not influenced by mane length or color, and 24‐hr mean T_b was negatively correlated with mane length. These data contradict the suggestion that there exists a thermal cost to male lions in possessing a long dark mane, but do not preclude the possibility that males compensate for a mane with increased heat loss. The increased insulation caused by a mane does not necessarily have to impair heat loss by males, which in hot environments is primarily through respiratory evaporative cooling, nor does in necessarily lead to increased heat gain, as lions are nocturnal and seek shade during the day. The mane may even act as a heat shield by increasing insulation. However, dominant male lions frequent water points more than twice as often as females, raising the possibility that male lions are increasing water uptake to facilitate increased evaporative cooling. The question of whether male lions with manes compensate for a thermal cost to the mane remains unresolved, but male lions with access to water do not have higher T_b than females or males with smaller manes.     

Embryology and early ontogeny of an endemic tooth‐carp fish,Aphanius sophiae (Heckel, 1847)

Understanding embryonic development and ontogeny of species is a crucial part of any further biology, ecology and conservation studies. The present study describes the first detailed normal embryonic development of a tooth‐carp, Aphanius sophiae (Heckel, 1847), from fertilization to post‐ hatching. Aphanius sophiae spontaneously spawned at 24 ± 1°C. The newly laid eggs were transparent and spherical (1.45 ± 0.20 mm). We documented developmental times at 24 ± 1°C to egg activation (0.5 hr), cleavage (3 hr), blastula (10 hr), gastrula (20 hr), neurula (24 hr), somite (28 hr), turnover (60 hr), blood circulation (70 hr) and hatching (330 hr). This study contributes to a further understanding of the embryology and the early ontogeny of A. sophiae and may help improve the culture of other threatened species of the genus Aphanius.     

Volatile organic compounds released by Rumex confertus following Hypera rumicis herbivory and weevil responses to volatiles

We report in this study large induction of volatile organic compounds (VOCs) from a single inflorescence of mossy sorrel (Rumex confertus Willd., Polygonaceae), by herbivory of the weevil (Hypera rumicis L., Coleoptera: Curculionidae). VOCs blend induced by the weevil herbivory included 1 green leaf volatiles (GLVs) ((Z)‐3‐hexen‐1‐yl acetate), five terpenes ((Z)‐β‐ocimene, linalool, geranyl acetate, β‐caryophyllene and (E)‐β‐farnesene), three esters (benzyl acetate, methyl salicylate and methyl anthranilate) and one aromatic heterocyclic organic compound (indole). Uninjured plants produced only detectable amounts of VOCs. A Y‐tube experiment revealed that both females and males of H. rumicis were not attracted to any of tested concentrations (1, 5, 25, 125 ng/min). Also both females and males were significantly repelled by the highest concentrations (25 and 125 ng/min). Additionally, concentration of 5 ng/min proved to be repellent for females of H. rumicis.     

Acarbose improves health and lifespan in aging HET3 mice

To follow‐up on our previous report that acarbose (ACA), a drug that blocks postprandial glucose spikes, increases mouse lifespan, we studied ACA at three doses: 400, 1,000 (the original dose), and 2,500 ppm, using genetically heterogeneous mice at three sites. Each dose led to a significant change (by log‐rank test) in both sexes, with larger effects in males, consistent with the original report. There were no significant differences among the three doses. The two higher doses produced 16% or 17% increases in median longevity of males, but only 4% or 5% increases in females. Age at the 90th percentile was increased significantly (8%–11%) in males at each dose, but was significantly increased (3%) in females only at 1,000 ppm. The sex effect on longevity is not explained simply by weight or fat mass, which were reduced by ACA more in females than in males. ACA at 1,000 ppm reduced lung tumors in males, diminished liver degeneration in both sexes and glomerulosclerosis in females, reduced blood glucose responses to refeeding in males, and improved rotarod performance in aging females, but not males. Three other interventions were also tested: ursolic acid, 2‐(2‐hydroxyphenyl) benzothiazole (HBX), and INT‐767; none of these affected lifespan at the doses tested. The acarbose results confirm and extend our original report, prompt further attention to the effects of transient periods of high blood glucose on aging and the diseases of aging, including cancer, and should motivate studies of acarbose and other glucose‐control drugs in humans.     

Hormonal differentiation of sexual behavior in Japanese quail

The effect of hormones on the development of Japanese quail during the postembryonic period was examined. First, subcutaneous implants of estradiol monobenzoate (EB) and testosterone propionate (TP) were implanted 6–12 hr after hatching. EB and TP had no effect on the differentiation of sexual behavior in genetic males or females. However, EB had marked feminizing effects on plumage in genetic males. Second, the role of gonadal hormones during development was examined by gonadectomizing males and females 6–12 hr after hatching and treating them intramuscularly with EB or TP as adults. EB-treated adult females displayed sexual behavior typical of the genetic female and developed female plumage. A significant proportion of TP-treated females (57%) displayed male sexual behavior patterns. Cloacal gland development and male-type vocalizations were induced. EB-treated males displayed either male or female sexual patterns depending on the stimulus conditions. Third, to test whether bisexuality in gonadectomized males and females is maintained despite steroid treatment and expression of sexual behavior in adulthood, gonadectomized quail which were originally treated with EB received TP and vice versa. The results indicate that in the absence of gonadal hormones after hatching female quail remain bisexual until exposed to estrogen, whereas gonadectomized male quail retain behavioral bisexuality irrespective of prior estrogen or androgen exposure.     

Lethal and sublethal effects of long‐lasting insecticide‐treated nets on the invasive bug Halyomorpha halys

Halyomorpha halys is a polyphagous insect species with an original eastern Asiatic distribution, which was recently and accidentally introduced in the USA and Europe, where it became a serious agricultural pest. Chemicals have been widely used for its control leading often to failure of IPM programmes. Several approaches aimed at pest monitoring and control are currently under investigation, for example trapping, screening, border management and biological control. In the present work, we investigated the lethal and sublethal effects of the use of a long‐lasting insecticide‐treated net (LLIN with α‐cypermethrin), focusing on the perspective to control H. halys in an integrated approach. All experiments were carried out in the laboratory either in small arenas, at five exposure times (5, 15, 30, 45 and 60 min) or in large cages at 8 hr exposure. In small arenas, the LLIN induced sublethal effects and/or effectively killed the adults. A higher adult mortality was observed after longer exposure times (LT₉₀ was 51.64 min for females and 40.83 min for males). However, several specimens recovered from sublethal effects, with higher recovery rates after shorter exposure times. In the cage experiments, a significantly higher mortality (65% males and 75% of females) was recorded compared with controls. LLINs are physical barriers that can improve crop protection due to their insecticidal activity, and can be reasonably applied in various attract‐and‐kill systems both in glasshouses and in the field.     

Synthesis of the same two proteins prior to larval diapause and pupation in the spruce budworm,Choristoneura fumiferana

Spruce budworm larvae produce large quantities of two proteins (Choristoneura fumiferana diapause associated proteins 1 and 2, CfDAP1 and CfDAP2) that are diapause related. These proteins appeared soon after hatching and increased in abundance, reaching maximum levels by four days into the 1st instar, and they remained at high levels until three days after the termination of diapause. These two proteins were purified to homogeneity and their NH2-terminal sequences were obtained. Oligonucleotide primers designed on the basis of these NH2-terminal sequences were used in RT-PCR to isolate the cDNA fragments coding for these proteins. These PCR fragments were then used as probes to isolate the cDNAs that contained the complete coding region. The 2.5kb mRNAs coding for these proteins started to appear 24hr after hatching and large quantities of these mRNAs were detected in 1st instar and 2nd instar larvae until the 2nd instar larvae entered diapause. Low levels of these mRNAs were detected in the 2nd instar larvae that were preparing to enter diapause, in those that were in diapause as well as in those that terminated diapause. Low levels of CfDAP1 mRNA were also detected on days 1 and 2 after ecdysis to the 3rd instar. However, no CfDAP1 and CfDAP2 mRNAs could be detected during the 4th and 5th instar larval stages. The mRNAs reappeared 24hr after the 5th instar larvae molted into the 6th instar and increased to reach maximum levels by 60hr after ecdysis. The mRNA levels remained high until 156hr after ecdysis into the 6th instar (36-48hr before pupal ecdysis), after which they disappeared once again. Immunocytochemical analyses showed that CfDAP1 protein was present in 2nd and 6th instar larval fat body but not in 5th instar larval fat body. Thus, the same two genes were expressed for the first time before C. fumiferana larvae entered diapause and for a 2nd time before pupation.     

Acarbose, 17‐α‐estradiol,and nordihydroguaiaretic acid extend mouse lifespan preferentially in males

Four agents — acarbose (ACA), 17‐α‐estradiol (EST), nordihydroguaiaretic acid (NDGA), and methylene blue (MB) — were evaluated for lifespan effects in genetically heterogeneous mice tested at three sites. Acarbose increased male median lifespan by 22% (P < 0.0001), but increased female median lifespan by only 5% (P = 0.01). This sexual dimorphism in ACA lifespan effect could not be explained by differences in effects on weight. Maximum lifespan (90th percentile) increased 11% (P < 0.001) in males and 9% (P = 0.001) in females. EST increased male median lifespan by 12% (P = 0.002), but did not lead to a significant effect on maximum lifespan. The benefits of EST were much stronger at one test site than at the other two and were not explained by effects on body weight. EST did not alter female lifespan. NDGA increased male median lifespan by 8–10% at three different doses, with P‐values ranging from 0.04 to 0.005. Females did not show a lifespan benefit from NDGA, even at a dose that produced blood levels similar to those in males, which did show a strong lifespan benefit. MB did not alter median lifespan of males or females, but did produce a small, statistically significant (6%, P = 0.004) increase in female maximum lifespan. These results provide new pharmacological models for exploring processes that regulate the timing of aging and late‐life diseases, and in particular for testing hypotheses about sexual dimorphism in aging and health.     

Effects of X‐ray irradiation on development and reproduction of the oriental tobacco budworm,Helicoverpa assulta (Lepidoptera: Noctuidae)

All stages of the life cycle of Helicoverpa assulta were irradiated with X‐rays to determine the inhibitory dose for development and reproduction to serve as a quarantine treatment. The 100‐Gy dose was effective for irradiation of eggs and larvae, and the 200‐Gy dose was effective for pupae and mixed‐sex adults. When either adult males or females were irradiated, however, 500 Gy was required to prevent the F1 eggs from hatching, and thus single‐sex adults required much higher doses of X‐ray irradiation. To gather confirmatory data applicable to phytosanitary quarantine regulations, pupae—the immature stage most resistant to X‐ray irradiation—were placed inside paprika in boxes for exportation and were irradiated with 300 Gy as a small‐scale confirmatory test. The dose given to 1,007 individual pupae resulted in 12.62 % survival, and 1.79 % of pupae emerged as normal adults; however, these adults produced only a few eggs that did not hatch, suggesting that a minimum dose of 300 Gy of X‐ray irradiation will provide quarantine security for immature H. assulta in paprika exports.     

Remating in Ceratitis capitata sterile males: Implications in sterile insect technique programmes

Sterile insect technique (SIT) is used, among other biological control tools, as a sustainable measure for the management of Ceratitis capitata Wiedemann (Diptera: Tephritidae) in many agricultural regions where this pest can trigger severe economic impacts. The tendency of wild females to remate multiple times has been deeply studied; it has been a common point of controversy when evaluating SIT programmes. Nevertheless, the remating potential of the released sterile males remains unknown. Here, under laboratory conditions, the remating capability of mass-reared sterile males was determined. Wild-type virgin females were offered to sterile males (Vienna-8 strain), which had the opportunity to mate up to four consecutive times. The remating assays were carried out at 24 hr, 48 hr, 4 days and 7 days after the first mating. At the end of each tested time period, males were divided according to their mating response, mated or unmated, and subsequently reused for the next round of mating assays. The frequency of successful remating in each tested time period was obtained. Insemination was confirmed by determining the sperm transfer in mated female spermathecae by quantitative real-time PCR. Our results demonstrate that 73% of the mass-reared sterile males were able to remate 24 hr after the first mating, 55% of which remated again the day after. Close to 25% of the V8 sterile males tended to copulate in all of the four mating opportunities. The qPCR analysis of the spermathecae contents verified an effective transfer of V8 sperm to wild females with every mating; 99% of copulations resulted in sperm transfer. These findings shed light on the remating potential of V8 sterile males, an aspect until now underestimated in many SIT programmes.     

Effect of female aging on the morphology and hatchability of resting eggs in the rotifer <Emphasis Type="Italic">Brachionus plicatilis</Emphasis> Müller

This study examined the morphology and hatchability of Brachionus plicatilis resting eggs as a function of the aging of maternal fertilized mictic females. One-hundred twenty fertilized B. plicatilis (Australian strain) were individually cultured and monitored daily until death. All cultures were maintained at 25°C, 11 ppt, and fed the micro-algae Tetraselmis tetrathele. Resting eggs produced by the females were investigated using two parameters: egg morphology, and hatching rate. Under these culture conditions, females normally produce 1–6 (mean ± SD = 2.7 ± 1.2) resting eggs during their lifetime. However, the number of resting eggs with abnormal morphology increased as a function of maternal age. Among resting eggs with normal morphology (n = 225), 82.2% were produced during the first and second spawning, and had hatching rates of more than 60%, while the hatching rates were below 30% in resting eggs with a spawning order of >2. Thus, the quality of B. plicatilis resting eggs was negatively correlated with maternal age.     

Repellency of lavender oil and linalool against spot clothing wax cicada,Lycorma delicatula (Hemiptera: Fulgoridae) and their electrophysiological responses

This study was performed to investigate the repellent effect of 5 μl doses of ten essential oils (bergamot, chamomile, clary sage, fennel, lavender, lemongrass, majoram, peanut, pennyroyal, and peppermint) against Lycorma delicatula 4th nymphs using an olfactometer. Only lavender oil exhibited significant repellency. We then tested 10, 5, 2.5, and 1 μl doses of lavender oil against the nymphs and females of L. delicatula. The oil showed significant repellency at 10 and 5 μl, although the latter is less potent to 1st instar nymphs. At the lavender oil dose of 2.5 μl, only 3rd and 4th instar nymphs and females were significantly affected. None of the stages tested were affected by 1 μl. Chromatographic and mass spectrometric analyses of lavender oil detected linalool (42.2%), linalyl acetate (49.4%), terpinen-4-ol (5.0%), and caryophyllene oxide (3.4%). Among the four main components, only linalool showed repellency to all instar nymphs and females. No synergism was detected. Antennae of all instar nymphs and females showed electrophysiological responses only to linalool. In field studies using linalool, 4th nymphs and adults were highly repelled at a dose of 30 μl of lavender oil. The effect differed according to test plot and treatment dose.     

Sex and occupation time influence niche space of a recovering keystone predator

Predators exert strong effects on ecological communities, particularly when they re‐occupy areas after decades of extirpation. Within species, such effects can vary over time and by sex and cascade across trophic levels. We used a space‐for‐time substitution to make foraging observations of sea otters (Enhydra lutris) across a gradient of reoccupation time (1–30 years), and nonmetric multidimensional scaling (nMDS) analysis to ask whether (a) sea otter niche space varies as a function of occupation time and (b) whether niche space varies by sex. We found that niche space varied among areas of different occupation times. Dietary niches at short occupation times were dominated by urchins (Mesocentrotus and Strongylocentrotus spp; >60% of diets) in open habitats at 10–40 m depths. At longer occupation times, niches were dominated by small clams (Veneroida; >30% diet), mussels (Mytilus spp; >20% diet), and crab (Decapoda; >10% diet) in shallow (<10 m) kelp habitats. Diet diversity was lowest (H′ = 1.46) but energy rich (~37 kcal/min) at the earliest occupied area and highest, but energy poor (H′ = 2.63, ~9 kcal/min) at the longest occupied area. A similar transition occurred through time at a recently occupied area. We found that niche space also differed between sexes, with bachelor males consuming large clams (>60%), and urchins (~25%) from deep waters (>40 m), and females and territorial males consuming smaller, varied prey from shallow waters (<10 m). Bachelor male diets were less diverse (H′ = 2.21) but more energy rich (~27 kcal/min) than territorial males (H′ = 2.54, ~13 kcal/min) and females (H′ = 2.74, ~11 kcal/min). Given recovering predators require adequate food and space, and the ecological interactions they elicit, we emphasize the importance of investigating niche space over the duration of recovery and considering sex‐based differences in these interactions.     

Predicting Sirex noctilio and S. nigricornis emergence using degree days

The study of temporal interactions between native insects and alien invaders can be facilitated by the ability to forecast adult emergence. We used field‐collected adult emergence data of Sirex noctilio Fabricius (Hymenoptera: Siricidae), a woodwasp native of Eurasia that has recently invaded northeastern North America, and Sirex nigricornis Fabricius, a woodwasp native to North America, to develop and test cumulative degree‐day (CDD) models. Five data sets were collected each in Ontario, Canada (S. noctilio) and Louisiana, USA (S. nigricornis) over 4 years; three data sets were used to develop models and two were used to test them. Males and females of each species were modelled separately. After testing several potential temperatures, chosen thresholds for CDD were 0 °C lower threshold and 25 °C upper threshold for both Sirex spp. We used a three‐parameter Gompertz growth function to model Sirex spp. emergence against CDD. Models predicted 10% emergence of S. noctilio in Ontario after 1 239 and 1 280 CDD, for males (start date = 1 April; R² = 0.91) and females (start date = 1 April; R² = 0.86), respectively. Models predicted 10% emergence of S. nigricornis in Louisiana after 3 980 and 5 016 CDD, for males (start date = 1 May; R² = 0.83) and females (start date = 1 March; R² = 0.73), respectively. Cumulative degree‐day models predicted 10 and 90% emergence of woodwasp populations with less error (1–13%) than they did 50% emergence (5–27%). For both Sirex spp., male emergence began a few days before and concluded at about the same time as that of females. In southern Ontario, models predict that S. noctilio adults will be in flight between 1 015 and 2 430 CDD (1 April start date for CDD; from early‐July until mid‐September). In Louisiana, models predict that S. nigricornis adults will be in flight between 3 854 and 4 700 CDD (1 May start date for CDD; from early‐October until late‐November).     

Sperm quality of Colossoma macropomum after room‐temperature and cold storage

The objective of this study was to evaluate the effects of cold and room‐temperature storage on the quality of Colossoma macropomum sperm. The experiment was carried out in December (end of Spring), in Nova Mutum‐MT, Brazil, involving nine C. macropomum males (4 years old; 6.4 ± 1.5 kg average weight). The fish were selected and transferred to masonry tanks (4 m³) in a laboratory (water renewal rate: 10 L/s; average water temperature: 28°C). Subsequently, reproduction was induced using 2.5 mg of crude carp pituitary extract/kg and the semen was harvested 240 degree hours after hormonal induction. The following sperm characteristics were analyzed every 5 hr using Image J/casa software: total motility (MOT), curvilinear velocity (VCL), average path velocity (VAP), straight‐line velocity (VSL), straightness of sperm path (STR), wobble (WOB), progressive motility (PROG), beat cross frequency (BCF) and total number of spermatozoa (NSPZ). A fresh sample of semen from each animal was kept at room temperature (25.3 ± 1.2°C). For analysis of cooled semen, syringes were kept in cooling boxes at an average temperature of 16.9 ± 2.1°C. The reduction (p < 0.05) of MOT in semen kept at room temperature occurred at 10 hr (13.95%); in cooled semen, however, MOT declined at 15 hr (76.87%). At 15 hr, there was practically no MOT in the semen kept at room temperature (0.20%), whereas in the cooled semen this situation was observed only at 35 hr (2.91%) The MOT of cooled sperm was higher (p < 0.05) at all times (except zero time), compared with the semen maintained at room temperature. At 15 hr, the cooled spermatozoa showed higher (p < 0.05) VCL (142.18 μm/s) and BCF (29.72 Hz) than those maintained at room temperature (VCL: 51.18 μm/s; BCF: 19.57 Hz). After 15 hr, only the cooled sperm showed quality. In conclusion, semen cooling allows for extending the viability of C. macropomum spermatozoa from 5 to 10 hr without compromising their quality in most characteristics. At 15 and 25 hr of cooling, sperm viability is still observed, though with decreased quality.     

Effects of algal food quality on sexual reproduction of Daphnia magna

The objective of our study was to investigate sexual reproduction of Daphnia magna associated with mating behaviors and hatching rates, according to different algal food sources. Since a diatom is known to contain more abundant long‐chain poly unsaturated fatty acids (PUFAs), we hypothesized that the diatom‐consuming D. magna would exhibit more successful reproduction rates. Upon the hypothesis, we designed three experiments using two algal species, a green alga (Chlorella vulgaris) and a diatom (Stephanodiscus hantzschii). From the results, we found that the mating frequency and copulation duration increased in the treatment with S. hantzschii, resulting in a significant increase of hatching rates of resting eggs. In the other two repetitive mating strategies (e.g., one female vs. multiple males, and one male vs. multiple females), we found that the hatching rates of resting eggs were greater in the S. hantzschii treatment. In addition to the mating strategy, male body size significantly increased in the diatom treatment, hence average diameter of penis was also statistically different among the treatments (greater diameter in the S. hantzschii treatment). To examine the effect of algal food quality, we estimated quantity of fatty acids in the two algal species. Our result showed that S. hantzschii had a higher proportion of long‐chain PUFAs than C. vulgaris. Furthermore, a stable isotope analysis revealed that carbon and nitrogen originated from S. hantzschii were more assimilated to D. magna. In summary, our study manifested that diatom consumption of D. magna leads to more successful sexual reproduction. We then discussed how the diatom consumption of zooplankton influences food web dynamics in a freshwater ecosystem.     

Glycine supplementation extends lifespan of male and female mice

Diets low in methionine extend lifespan of rodents, though through unknown mechanisms. Glycine can mitigate methionine toxicity, and a small prior study has suggested that supplemental glycine could extend lifespan of Fischer 344 rats. We therefore evaluated the effects of an 8% glycine diet on lifespan and pathology of genetically heterogeneous mice in the context of the Interventions Testing Program. Elevated glycine led to a small (4%–6%) but statistically significant lifespan increase, as well as an increase in maximum lifespan, in both males (p = 0.002) and females (p < 0.001). Pooling across sex, glycine increased lifespan at each of the three independent sites, with significance at p = 0.01, 0.053, and 0.03, respectively. Glycine‐supplemented females were lighter than controls, but there was no effect on weight in males. End‐of‐life necropsies suggested that glycine‐treated mice were less likely than controls to die of pulmonary adenocarcinoma (p = 0.03). Of the 40 varieties of incidental pathology evaluated in these mice, none were increased to a significant degree by the glycine‐supplemented diet. In parallel analyses of the same cohort, we found no benefits from TM5441 (an inhibitor of PAI‐1, the primary inhibitor of tissue and urokinase plasminogen activators), inulin (a source of soluble fiber), or aspirin at either of two doses. Our glycine results strengthen the idea that modulation of dietary amino acid levels can increase healthy lifespan in mice, and provide a foundation for further investigation of dietary effects on aging and late‐life diseases.     

Prebreeding survival of Roseate Terns Sterna dougallii varies with sex,hatching order and hatching date

Unequal sex ratios can reduce the productivity of animal populations and are especially prevalent among endangered species. A cohort of 333 Roseate Tern Sterna dougallii chicks at a site where the adult sex ratio was skewed towards females was sexed at hatching and followed through fledging and return to the breeding area, and subsequently during adulthood. The entire regional metapopulation was sampled for returning birds. Prebreeding survival (from fledging to age 3 years) was lower in males than in females, but only among B‐chicks (second in hatching order). Prebreeding survival also declined with hatching date. The proportion of females in this cohort increased from 54.6% at hatching to 56.2% at fledging and to an estimated 58.0% among survivors at age 3 years. This was more than sufficient to explain the degree of skew in the sex ratio of the adult population, but changes in this degree of skew during the study period make it difficult to identify the influence of a single cohort of recruits. Many studies of prebreeding survival in other bird species have identified effects of sex, hatching order or hatching date, but no previous study has tested for effects of all three factors simultaneously.