Distribution of the bridled form of the Common guillemot Uria aalge in the North Atlantic

This study documents the fourth survey (198 1–1982) of bridled guillemots and provides the most complete information yet available on the distribution of the bridled form of the Common guillemot. The distribution has remained largely unchanged since the last survey (1959-60), although marked changes have occurred at a few colonies. Sea surface temperature "explains" only 35% of the variance in the proportion of bridled guillemots. Minimum air temperatures during the breeding season are much more closely correlated with bridling and "explain" 60% of the variance. No relationship exists between sea temperatures and the proportion of bridled guillemots in wintering areas. The distribution of bridled guillemots may represent the slow, southward spread of the bridled form. Alternatively, selection may favour the bridled form in cooler areas. There is insufficient evidence to distinguish between these two hypotheses, but if selection is important, the correlations with environmental factors suggests that it operates during the breeding season rather than at other times.     

Increase in frequency of the bridled morph of the Common Guillemot Uria aalge on the Isle of May, 1946–2000: a return to former levels?

Bridling in the Common Guillemot Uria aalge is a classic example of a stable ratio-cline polymorphism. Between 1946 and 2000 the frequency of the bridled morph of the Common Guillemot colony on the Isle of May, south-east Scotland, increased significantly from 3.5% to 5.9%. Demographic data collected between 1982 and 2000 indicated that the average breeding success of a pair including at least one bridled bird was 83.8%, significantly greater than 79.5% in unbridled pairs. Over the same period the average overwinter survival was 96.3% for bridled birds and 94.7% for unbridled birds, but the difference was not statistically significant. A population model showed that the increase in frequency of bridling could be accounted for as a return to an equilibrium level close to the 5.04% observed in 1936. Differences in breeding success contributed relatively little to the increase, which could be explained without recourse to differential selection pressure. The latitudinal variation in bridling suggests that bridled morphs are more cold tolerant than unbridled ones. However, the increase in the frequency of bridled birds on the Isle of May was not associated with any decrease in sea or air temperatures over the period.     

A comparison of the biology of the normal and bridled forms of the Guillemot Uria aalge at a single colony

The proportion of Guillemots on the Isle of May showing bridling has remained constant for 49 years. Although clumping of birds occurred, there was no obvious assortment of sexes. We detected no systematic differences in the breeding of bridled and normal individuals.     

Common species affects the utility of non‐invasive genetic monitoring of a cryptic endangered mammal: The bridled nailtail wallaby

Non‐invasive methods of monitoring wild populations (such as genotyping faeces or hair) are now widely used and advocated. The potential advantages of such methods over traditional direct monitoring (such as live capture) are that accuracy improves because sampling of non‐trappable individuals may be possible, species in difficult and remote terrain can be surveyed more efficiently, and disturbance to animals is minimal. Few studies have assessed the effects of interactions between species on remote sampling success. We test the use of non‐invasive monitoring for the cryptic, forest‐dwelling, solitary and endangered bridled nailtail wallaby (Onychogalea fraenata) that is sympatric with the ecologically similar and more common black‐striped wallaby (Macropus dorsalis). Six types of hair traps were tested for 3668 trap days, and hairs were caught with about a 10% success rate. Camera traps showed that baited hair traps targeted both wallaby species. We microscopically identified hair as bridled nailtail wallaby or black‐striped wallaby. We compared these hairs and their genotypes (using seven microsatellite loci) with known bridled nailtail wallaby hairs and genotypes derived from animal trapping. Trapped bridled nailtail wallaby hairs had characteristics that could be mistaken for black‐stripe wallaby hairs; characteristics were not diagnostic. Genetic assignment tests consistently differentiated the known bridled nailtail wallaby samples from identified black‐striped wallaby samples, however genetic overlap between most of the microsatellite markers means that they are not suitable for species identification of single samples, with the possible exception of the microsatellite locus B151. With similar trapping effort and within the same area, live‐capture mark‐recapture techniques estimated 40–60 individuals and non‐invasive methods only detected 14 genotypes. A species‐specific genetic marker would allow more efficient targeting of bridled nailtail wallaby samples and increase capture rates.     

Activation of the serotonergic system in chick spinal cord during hatching.

The objectives of the present study were to determine the levels of serotonin (5-HT), its major catabolic metabolite, 5-hydroxyindoleacetic acid (5-HIAA), and norepinephrine (NE) in chick spinal cord before, during, and after hatching and also to determine if changes in the levels of these chemicals are directly related to the hatching behavior. The levels of 5-HT, 5-HIAA, and NE were measured by high performance liquid chromatography with electrochemical detection in whole spinal cords of 20-day-old "pre-hatching" embryos, 21-day-old "normal hatching" embryos, 0-day-old "post-hatching" chicks, and 0-day-old "glass egg hatching" chicks. NE was measured but no significant differences were found in NE levels among experimental groups. The concentration of 5-HT was elevated in chick embryo spinal cords during normal hatching compared to pre-hatching embryos and post-hatching chicks. The concentration of 5-HIAA was elevated during and after normal hatching compared to pre-hatching embryos. However, neither 5-HT nor 5-HIAA levels were found to be elevated in chick spinal cords during glass egg hatching compared to pre-hatching embryos or post-hatching chicks. Therefore, there appears to be an activation of the serotonergic system in chick spinal cord related to the specific event of hatching but this activation is not directly related to the movements common to both hatching and glass egg hatching.     

Variation in chick‐a‐dee calls of bridled titmice (Baeolophus wollweberi): Frequent use of non‐combinatorial calls in a combinatorial calling system

Chick‐a‐dee calls of Poecile (chickadee) and Baeolophus (titmouse) species are complex in terms of the structural composition of note types and the diversity of messages. Studies so far have mainly focused on the calls of various chickadee and just one titmouse species—the tufted titmouse (B. bicolor). To begin to address this lack of titmouse data, our study investigated variation in note composition of calls of bridled titmice (B. wollweberi). We obtained calls from 26 flocks in the Chiricahua Mountains of Arizona in the overwintering flocking period. Bridled titmice produce proportionally more non‐combinatorial call variants than combinatorial call variants. The number of the single noted calls furthermore exceeded the number of multinote calls. In general, structural variation in the combinatorial calls appears to be comparable to calls of better‐studied chickadees and of tufted titmice, although bridled titmice appear to have a unique call length distribution. We also analyzed some behavioral associations with call variation and found that flight behavior and close interactions between individuals were associated with use of specific note types. Finally, we found microgeographic variation in note type use in these calls. We discuss some possible explanations for call complexity in this species.     

Non-random, intra-colony distribution of bridled guillemots Uria aalge

Within the Common guillemot Uria aalge colony, at the Gannet Clusters, Labrador, Canada, there was no evidence of heterogeneity in the proportion of bridled birds in different parts of the colony. Nor was there any evidence for assortative mating among bridled guillemots. Examination of the distribution of bridled birds in rows of guillemots however, showed a significant degree of clumping. Two hypotheses are presented to explain this distribution pattern: (a) the environmental hypothesis, which proposes that bridled birds preferentially select particular micro-habitats, or choose to breed where there are already bridled birds. (b) the return hypothesis, which proposes that one sex (probably female) returns to breed very close to where it was reared.     

A comparison of bridled and bridle‐less ichthyoplankton nets in a variable flow estuarine environment

The effectiveness of bridled and bridle‐less plankton nets for sampling ichthyoplankton from a fixed structure in a variable flow environment was examined. From 22 June to 19 September 2011, larval and juvenile fishes were collected weekly during night flood tides from the Moon River, an estuarine tidal creek south of Savannah, Georgia, USA. Passive horizontal tows were made from a fishing pier using two ichthyoplankton nets, each with a 1 m diameter hoop and 1 mm mesh. A bridled plankton net was configured with a tow rope attached to a traditional three‐point bridle anchored to the hoop and a closed, 1 L collection jar at the cod end. A bridle‐less net was configured with a tow rope and a float tied to the top of the hoop while a weight was tied to the bottom of the hoop. The cod end of the bridle‐less net had an open collection bucket with 1 mm mesh. Nets were deployed simultaneously in the water column, just below the surface, for three consecutive 30‐min tows. For each sampling date, pair‐wise comparisons of nets were performed on mean values of fish abundance, species richness, species diversity, and species evenness. Mean abundance was the only consistent difference between bridled and bridle‐less nets, with the bridle‐less net having on average 4.870 times more fishes. Species richness (as measured by both number of species and Margalef's species richness index) tended to be greater in the bridle‐less net, but not significantly greater. Species diversity (Shannon‐Wiener diversity index) and species evenness (Pielou's evenness index) were also not significantly different between the two nets.     

Chick growth and survival in gentoo penguins (Pygoscelis papua): effect of hatching asynchrony and variation in food supply

Summary In the gentoo penguin, Pygoscelis papua, we examined the effects of intra-clutch egg size differences and hatching asynchrony on differential chick growth and survival (including post-fledging survival), in five years for which indices of food supply were available. An initial size hierarchy within-broods at hatching was due to hatching asynchrony not intra-clutch egg size differences. In 1988 only (a poor food year), the weight advantage gained by the first-hatched (A) chick persisted to the end of brooding (30 days), with more second-hatched (B) chicks dying. There was no difference between A- and B-chick weights at fledging (60 days) or in overall chick survival between synchronous and asynchronous broods in any year. Postfledging survival (measured in one year) was not related to fledging weight or hatching order. These results provide only partial support for the hypothesis that gentoo penguins operate a brood reduction strategy to optimise chick survival in years of low food availability. We suggest that hatching asynchrony in gentoo penguins may result from selection to keep the first egg warm as soon as it is laid, due to extreme low ambient temperatures.     

Do Gene Variants Influencing Adult Adiposity Affect Birth Weight? A Population-Based Study of 24 Loci in 4,744 Danish Individuals

Background

Several obesity risk alleles affecting adult adiposity have been identified by the recent wave of genome wide association studies. We aimed to examine the potential effect of these variants on fetal body composition by investigating the variants in relation to birth weight and ponderal index of the newborn.

Methodology/Principal Findings

Midwife records from the Danish State Archives provided information on mother''s age, parity, as well as birth weight, birth length and prematurity of the newborn in 4,744 individuals of the population-based Inter99 study. Twenty-four risk alleles showing genome-wide associations with adult BMI and/or waist circumference were genotyped. None of the 24 risk variants tested showed an association with birth weight or ponderal index after correction for multiple testing. Birth weight was divided into three categories low (≤10^th percentile), normal (10^th–90^th percentile) and high birth weight (≥90th percentile) to allow for non-linear associations. There was no difference in the number of risk alleles between the groups (p = 0.57). No interactions between each risk allele and birth weight in the prediction of adult BMI were observed. An obesity risk score was created by summing up risk alleles. The risk score did not associate with fetal body composition. Moreover there was no interaction between the risk score and birth weight/ponderal index in the prediction of adult BMI.

Conclusion

24 common variants associated with adult adiposity did not affect or interact with birth weight among Danes suggesting that the effects of these variants predominantly arise in the post-natal life.     

Conformational Equilibria of Bridled Chiroporphyrins in Solution Investigated by Vibrational Circular Dichroism

A series of bridled chiroporphyrins (BCP) and their metal complexes were prepared, in which two n‐methylene straps connect adjacent meso substituents by ester linkages. These compounds can exist as four atropisomers (αααα, αβαβ, αααβ, or ααββ) depending on the position of the meso groups relative to the macrocycle (α when above and β when below). We characterized the conformation of these chiral porphyrins and their metal (Zn, Ni, Mn) complexes by vibrational circular dichroism (VCD) associated with ab initio calculations. VCD spectra of the three metalloporphyrins were recorded in CDCl₃ and benzene solutions and ab initio calculations of their four atropoisomers were performed at the Density Functional Theory (DFT) level. The bridled chiroporphyrin with the longer straps (9 CH₂) and its nickel(II) complex can be isolated as the αβαβ atropisomer in the solid state and were found with the same conformation in CDCl₃ and benzene solutions. The bridled chiroporphyrin with the shortest straps (8 CH₂) and its zinc(II) complex can be isolated as the αααα atropisomer in the solid state, but in solution they are subject to atropisomeric equilibria, resulting in atropisomer distributions that are strongly solvent‐dependent. Comparison of the experimental VCD spectra with the predicted spectra of the four atropisomers allowed the quantification of these distributions. Finally, the manganese(III) complex also exhibits an atropisomeric equilibria in solution which is slightly solvent‐dependent. Chirality 25:480–486, 2013. © 2013 Wiley Periodicals, Inc.     

Growth of nestling black kites Milvus migrans: effects of hatching order, weather and season

The growth of black kites Milvus migrans was studied in 1981, 1982 and 1984 at the Doñana Biological Reserve (south-west Spain). Fifteen variables were submitted to a principal component analysis in order to characterize the growth pattern of the young. In general, in the nestlings that fledged, rapid weight gain corresponded to rapid growth of the tarsus and feathers. For nestlings that starved, tarsus growth took priority over weight gain. Within the same brood, the last-hatched sibling grew more slowly than its older sibling and the differences between them increased in proportion to the hatching asynchrony. Brood size did not affect growth as clearly as hatching order and hatching asynchrony. Increased rainfall and lower maximum temperature, factors that seem to make the search for food more difficult, had negative effects on the youngest sibling in a multiple brood and on single nestlings. The only environmental variable that had an effect on all of the nestlings was the hatching date.     

Characterization of three electrophoretic variants of human erythrocyte triosephosphate isomerase found in Japanese

Three new electrophoretic variants of human erythrocyte triosephosphate isomerase (TPI) have been partially purified and compared with the normal isozyme with respect to stability, kinetics, and immunological properties. TPI 2HR1, an anodally migrating variant, was less stable than normal in guanidine denaturation and thermodenaturation tests, although it exhibited normal kinetic properties. The level of enzyme activity in erythrocytes from the proband with the phenotype TPI 1-2HR1 was about 60% of the normal mean. The variant allozyme TPI 2NG1, an anodally migrating allozyme associated with normal activity, was very thermolabile at 55 and 57°C. It was also much more labile than normal in stability tests in buffers at pH 5 and pH 10, although it exhibited normal kinetic and immunological properties. TPI 4NG1, a cathodally migrating variant associated with normal activity and normal kinetic as well as immunological properties, was more stable than normal in pH 5 buffer. Family studies demonstrated that the unique characteristics of these variants are genetically transmitted. In two-dimensional electrophoresis of purified isozymes the variant subunits were separated from the normal in the pI axis. However, there is no difference between the variants and the normal in the molecular weight axis, suggesting that the variants result from single amino acid substitutions.     

Half-site strand transfer by step-arrest mutants of yeast site-specific recombinase Flp.

The Flp recombinase of Saccharomyces cerevisae can mediate strand transfer within a half-site, between two half-sites and between a half-site and a full-site. The ability of "step-arrest" mutants of Flp to partake in half-site reactions has been examined. Arg308 variants of Flp, which show little or no strand cleavage in reactions with normal full-sites, execute significant levels of strand transfer in half-site reactions. On the other hand, His305 variants of Flp, which normally accumulate the strand cleavage product from full-sites but do not complete strand transfer, yield only minute amounts of strand transfer products from half-sites. As would be predicted, the step-arrest mutants are unable to produce "normal" or "reverse" recombinants between a half-site and a full-site. The Flp protein is able to form higher-order complexes in association with a half-site. The step-arrest mutants of Flp show specific defects in forming these complexes.     

Ultrastructural changes in hatching-gland cells of pike embryos (Esox lucius L.) and evidence for their degeneration by apoptosis

Summary Around hatching, when the pike embryo sheds its acellular egg envelope, marked changes occur in the cellular covering of the embryo. This cellular covering consists of a peridermal layer and a mono-layered presumptive epidermis. The periderm begins to disintegrate shortly before hatching and is sloughed off in the first posthatching period. The cellular covering produces hatching enzyme, the protease that partly dissolves the zona radiata interna of the acellular envelope. By means of the peroxidase-anti-peroxidase staining method with antibodies against hatching enzyme the cells producing this enzyme (hatching gland cells, HGCs) could be identified ultrastructurally. They are interspersed as single cells between the periderm and the presumptive epidermis. The secretory cycle of the HGC was studied. Hatching enzyme is released by an exocytotic secretory process in which multiple secretion into a secretion vacuole predominates. Exocytosis into surrounding intercellular spaces also occurs. These results show that the HGCs are merocrine glands. The HGC also has some holocrine nature, however, in that only a single, massive release of its secretory product occurs. The death of the transitory HGCs in posthatching stages is characterized by condensation of the cell, formation of surface protuberances and splitting up into globular cell fragments. Eventually these fragments are ingested by epidermal cells and digested. These results lead to the conclusion that the pike HGCs degenerate by apoptosis, unlike true holocrine cells.     

Allelic variants of melanocortin 3 receptor gene (MC3R) and weight loss in obesity: a randomised trial of hypo-energetic high- versus low-fat diets

Introduction

The melanocortin system plays an important role in energy homeostasis. Mice genetically deficient in the melanocortin-3 receptor gene have a normal body weight with increased body fat, mild hypophagia compared to wild-type mice. In humans, Thr6Lys and Val81Ile variants of the melanocortin-3 receptor gene (MC3R) have been associated with childhood obesity, higher BMI Z-score and elevated body fat percentage compared to non-carriers. The aim of this study is to assess the association in adults between allelic variants of MC3R with weight loss induced by energy-restricted diets.

Subjects and Methods

This research is based on the NUGENOB study, a trial conducted to assess weight loss during a 10-week dietary intervention involving two different hypo-energetic (high-fat and low-fat) diets. A total of 760 obese patients were genotyped for 10 single nucleotide polymorphisms covering the single exon of MC3R gene and its flanking regions, including the missense variants Thr6Lys and Val81Ile. Linear mixed models and haplotype-based analysis were carried out to assess the potential association between genetic polymorphisms and differential weight loss, fat mass loss, waist change and resting energy expenditure changes.

Results

No differences in drop-out rate were found by MC3R genotypes. The rs6014646 polymorphism was significantly associated with weight loss using co-dominant (p = 0.04) and dominant models (p = 0.03). These p-values were not statistically significant after strict control for multiple testing. Haplotype-based multivariate analysis using permutations showed that rs3827103–rs1543873 (p = 0.06), rs6014646–rs6024730 (p = 0.05) and rs3746619–rs3827103 (p = 0.10) displayed near-statistical significant results in relation to weight loss. No other significant associations or gene*diet interactions were detected for weight loss, fat mass loss, waist change and resting energy expenditure changes.

Conclusion

The study provided overall sufficient evidence to support that there is no major effect of genetic variants of MC3R and differential weight loss after a 10-week dietary intervention with hypo-energetic diets in obese Europeans.     

A review of Mauthner-initiated escape behavior and its possible role in hatching in the immature zebrafish,Brachydanio rerio

Synopsis In certain fish rapid escape responses have been observed to occur from early stages of embryogenesis. It is the purpose of this review to consider the development of one escape pattern, the C-type fast-start. During this behavior the animal initially coils its body into the shape of a letter C, and then rapidly uncoils and propels itself through the water. Relative to body size, the speed of the embryonic and larval C-start is comparable with that of the adult. These responses in the zebrafish, Brachydanio rerio, are utilized in the escape from predators, such as the protozoan Coleps sp. C-starts are triggered by the firing of one of the Mauthner (M-) cells, a single pair of large neurons in the brain stem. These neurons receive a rich supply of connections from sensory and integrative centers in the brain. The M-cells activate the escape movement by driving motor and relay neurons controlling the various muscular contractions associated with the behavior. During hatching, the rupturing of the egg envelope appears to be triggered by strong tail contractions following dissolution of the envelope by hatching enzymes. These contractions are similar to those known to be driven by the M-cell. The M-cell fires spontaneously up to the normal time of emergence from the egg, but is quiescent afterwards. This spontaneous activity of the M-cell may result in behavior that helps to break the egg envelope. The M-cell also reliably fires to repeated stimulation up to about the normal time of hatching, but habituates rapidly thereafter. We suggest that the M-cell may be utilized in escaping from the egg when it is under attack by a small predator.     

Chromosome abnormalities in newborn children. Physical aspects

Summary A chromosome examination was made on 11,148 consecutively live-born children: 93 had a chromosome abnormality and 192 a chromosome variant. The physical aspects of the children with chromosome abnormalities and variants were compared with those of the children with normal karyotypes. Children with aneuploid or unbalanced chromosome abnormalities were more frequently immature or not fully developed at birth than those with normal karyotypes. Birth weight was lower in children with all types of chromosome abnormalities, including reciprocal translocations and chromosome variants. The low birth weight in children with chromosome variants was mainly due to the low birth weight of children with G variants. These children were also subject to a higher frequency of special delivery treatment. Heart disorders were increased in children with aneuploid or unbalanced chromosome abnormalities. The frequency of foetal erythroblastosis was increased in children with short Y as well as in children with acentric fragments. Neonatal mortality was higher in children with aneuploid or unbalanced chromosome abnormalities than in children with normal karyotypes.     

四川南充白颊噪鹛的繁殖行为观察

2009年2～6月,在四川省南充市市郊观察了白颊噪鹛(Garrulax sannio)的繁殖行为。结果显示,白颊噪鹛的营巢成功率为73.3%,影响其巢址选择的主要因素依次为巢位及巢的稳固因素、隐蔽因素、食物因素;孵化期亲鸟的离巢时间随着孵化天数的增加而减少,离巢次数随着孵化天数的增加而增加;育雏期亲鸟喂食频次随着雏鸟日龄增加而增加,且在日间各时段的喂雏次数不同,在7:01～10:00时和17:01～19:00时喂食频次最高,在6:30～7:00时和10:01～14:00时最低;育雏期雏鸟的外部形态变化明显,体长及外部器官的形态学参数可以用Logistic曲线方程很好地拟合,雏鸟体重和各器官的生长曲线在10.5日龄前呈"S"型;白颊噪鹛的繁殖成功率为23.1%。