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We measured bird diversity over an 800 m range in altitude to test the factors that influence changes in diversity, in the Atlantic Forest in the state of Sao Paulo, Brazil. We counted forest birds in nine 100 m transects comprising three-point counts, the center of each separated by 200 m. A total of 108 species were found, and diversity was distributed among sampling points and altitude formed a trough-shaped relationship of number of species by area, altitude, and, most strongly, slope. In Principal Coordinate Analysis we found that grouping points by similarity formed three distinct units that were united by altitude: the lowest at near sea level, 100–400 m, and 500–800 m. Thus, we demonstrate that, in the Atlantic Forest, turnover of species with altitude occurs, but unlike higher, often steeper, tropical gradients in Andean forests, where vegetation more clearly changes with elevation, species turnover is more likely to be associated with variables other than changes in vegetation, and which are often not included in studies of the elevation gradient in species richness. The mid-domain effect did not explain altitudinal gradient in diversity, while a quadratic relationship with altitude did, suggesting that reduced abundance and diversity are associated with steeper slopes.

PURPOSE: Down syndrome (DS) is caused by trisomy 21 (Ts21) and results in skeletal deficits including shortened stature, low bone mineral density and a predisposition to early onset osteoporosis. Ts21 causes significant alterations in skeletal development, morphology of the appendicular skeleton, bone homeostasis, age-related bone loss, and bone strength. However, the genetic or cellular origins of DS skeletal phenotypes remain unclear. RECENT FINDINGS: New studies reveal a sexual dimorphism in characteristics and onset of skeletal deficits that differ between DS and typically developing individuals. Age-related bone loss occurs earlier in the DS as compared to general population. SUMMARY: Perturbations of DS skeletal quality arise from alterations in cellular and molecular pathways affected by the overexpression of trisomic genes. Sex-specific alterations occur in critical developmental pathways that disrupt bone accrual, remodeling, and homeostasis and are compounded by aging, resulting in increased risks for osteopenia, osteoporosis and fracture in individuals with DS.

Epigallocatechin-3-gallate (EGCG) is a candidate therapeutic for Down syndrome (DS) phenotypes based on in vitro inhibition of DYRK1A, a triplicated gene product of Trisomy 21 (Ts21). Consumption of green tea extracts containing EGCG improved some cognitive and behavioral outcomes in DS mouse models and in humans with Ts21. In contrast, treatment with pure EGCG in DS mouse models did not improve neurobehavioral phenotypes. This study tested the hypothesis that 200 mg/kg/day of pure EGCG, given via oral gavage, would improve neurobehavioral and skeletal phenotypes in the Ts65Dn DS mouse model. Serum EGCG levels post-gavage were significantly higher in trisomic mice than in euploid mice. Daily EGCG gavage treatments over three weeks resulted in growth deficits in both euploid and trisomic mice. Compared to vehicle treatment, EGCG did not significantly improve behavioral performance of Ts65Dn mice in the multivariate concentric square field, balance beam, or Morris water maze tasks, but reduced swimming speed. Furthermore, EGCG resulted in reduced cortical bone structure and strength in Ts65Dn mice. These outcomes failed to support the therapeutic potential of EGCG, and the deleterious effects on growth and skeletal phenotypes underscore the need for caution in high-dose EGCG supplements as an intervention in DS.

Nest prospecting, that is, visiting potential future nest sites, may be a widespread bird behavior. Here we describe apparent prospecting while nesting by white-rumped swallows (Hirundinidae, Aves). In southern Brazil, birds tagged with passive-integrated transponders (PIT-tags) and breeding in nest boxes with PIT-tag readers: (1) often visited nest boxes that were in use by apparently unrelated birds (54 % of nests were visited at least once), (2) visited other boxes while caring for their own nestlings, (3) tended to have smaller broods than birds that were not recorded visiting, and (4) did not have a preference for any particular box. These patterns do not indicate any clear explanation for nest visiting, but they do show that prospecting is done by floaters (non-breeders) as well as actively breeding individuals. We suggest that these visits occur when time is available and that visitors may be assessing the availability of future nest sites.

he Southern Lapwing (Vanellus chilesnis) is a common bird in Southern America and commonly found in any large open areas, including agriculture and urban. The lapwing is a facultative cooperative breeder and aggressively defends its breeding territory. Thus, the breeding system and their consequences for reproductive success are interesting for evolutionary biology. Capture of the lapwing, however, is difficult. Most studies to date have not captured or individually marked birds even though identifying individuals to examine their roles in the breeding units is essential for understanding group evolution and interactions. Here we describe ways to efficiently capture the Southern Lapwing during the breeding season using mist-nets at night and by taking advantage of their defensive behaviors. Before hatching, nets were placed inside the breeding territories and by strategically walking towards the birds they were guided towards the nets, in which they fell when taking flight. After hatching, we captured the young birds and held them near the nets in which the adults fell when defending them. By using these methods, we captured 78 birds during the 2012 and 2013 breeding seasons. We observed no nest nor territory abandonment after captures. We suggest that our methods are useful in most situations with lapwings and better capture and marking will contribute to developing long-term population monitoring.

Secondary transport of introduced species can be important in dispersing potentially invasive species, and vectors of transport are often the fouled hulls of small fishing and recreational boats. Likelihood of transport depends on many factors, including resistance of the species to drag forces due to boat velocity and resistance to desiccation. To experimentally test the importance of drag on transport, we attached plates with a preexisting, 4 months old, assemblage of species, on a boat hull that was then subjected to one of three speeds (5, 15 and 20 knots) for 20 min. We experimentally tested desiccation tolerance with colonized plates that were exposed to the air for 3–132 h, after which they were examined for living organisms. A total of 35 taxa were identified, including introduced species, in southern Brazil: the barnacles Amphibalanus amphitrite, A. reticulatus and the octocoral Stragulum bicolor. In the drag experiment, all species survived transport. In the desiccation experiment, most species survived more than 6 h (fewer species much longer) of exposure to the air. Our results illustrate that a variety of taxa and growth forms can be transported over regional scales at speeds and travel conditions typical of small boats. They can also survive desiccation conditions typical of overland transportation of small boats. Thus, we recommend that additional management mechanisms must be put in place to reduce the probability of invasion due to secondary transport.

Examples from a variety of taxa demonstrate that under certain circumstances, the exclusion or translocation of ‘problem’ animals is ineffective in resolving human–wildlife conflicts and may even elicit new problems elsewhere. Damage caused by badger setts (burrows) is an important source of human–wildlife conflict in the UK and is commonly managed by excluding badgers from all or part of problem setts. We used records of licences issued for the management of such problems and a novel statistical approach to assess spatiotemporal associations between problem cases in England from 2002 to 2005. We predicted that management at urban badgers' setts, and particularly exclusion of badgers from urban main setts, would give rise to subsequent problems at focal setts and in neighbouring areas. Frequencies of problems occurring at individual setts were similar in urban and rural areas. In areas neighbouring setts subjected to management action, the background frequency of problems was higher in urban than in rural areas, reflecting the occurrence of problems at a higher proportion of urban setts. The frequency of new cases arising at or in the vicinity of managed setts within a critical time period after management action was not significantly different from the background frequency of problems for any combination of land use, sett type and management approach. This finding suggests that the measures currently employed for managing problem setts do not importantly increase the likelihood of problems reoccurring in the same location or emerging nearby.

Stone martens (Martes foina) occur in urban environments in many parts of continental Europe, where they cause a nuisance by denning in inhabited houses. We radio tracked 13 stone martens (10 females, 3 males) in two towns in southern Luxembourg during a 2-year period, in order to investigate den preferences and patterns of den use. We predicted that urban martens would make more use of buildings and less use of natural den sites than do their rural counterparts. All martens used multiple den sites but use was concentrated on a subset of these, between which individuals shifted frequently. Denning was almost exclusively in buildings (97.1%), with use of inhabited buildings being the highest (41.9%) recorded to date for this species. Inhabited buildings were used more extensively in winter, presumably because they were warmer and better insulated. We conclude that stone martens can successfully adapt their denning behaviour to an urban environment and that they use anthropogenic den sites more often than do most other mesocarnivore urban adapters.

Exotic species invasions are one of the greatest threats to marine systems and ascidians have many characteristics that favor transport, colonization and establishment into new regions. Didemnum perlucidum is a widespread species that has been introduced into tropical ports around the world. Here we examine the colonizing ability of D. perlucidum by experimental use of artificial plates in a shellfish culture. The experiment comprised paired plates for colonization (bare and occupied) in 16 monthly replicates. Recruitment and space occupation were compared between bare and occupied plates and an estimation of reproductive effort was based on the number of larvae produced in each of ten colonies collected on the culture structures. D. perlucidum reproduced continuously but greatest reproduction occurred between December 2006 and May 2007. While recruitment was somewhat greater (number of new colonies) on bare plates, this species can colonize already occupied substrates and, surprisingly, colony area was always similar between treatments. Thus, while fewer colonies formed on occupied plates, once formed, colonies grew at rates similar to those on clean plates. Thus, D. perlucidum colonizes substrates very efficiently, especially when unoccupied space is available.

Annual patterns of fecal corticoid excretion were analyzed in the threatened Red-tailed parrot (Amazona brasiliensis) in captivity. Corticoid concentration over the 15 months of the study (mean +/- standard error, 12.6 +/- 0.32 ng g(-1), n = 585) was lowest around May (the southern Fall), and greatest around September (late winter), just prior to their normal breeding period. Corticoid excretion follows a seasonal pattern best explained by reproductive cycles rather than climate, although climate may be involved in the timing of corticoid excretion. Fecal corticoids also show promise as a tool to measure stress levels. We demonstrate that fecal corticoid measurement is a simple, yet efficient method for monitoring adrenocortical activity in captive, and perhaps wild, parrots. Monitoring adrenocortical activity can inform researchers about imposed stress in captivity, whether pair-bonds are forming in captive birds, and of the timing of breeding both in captivity and in nature.

We radio-tracked one urban wild-caught and four orphaned captive-reared stone martens (Martes foina) after translocation to novel habitats. The wild-caught marten rapidly returned to urban habitat but died 7 days after release. The captive-reared martens survived >130 days after release. An initial period of extensive movements was followed by decreased activity. Captive-reared martens apparently adapted well to living in the wild. However, we recommend that exclusion of martens from den sites should be used to avoid having to resort to the capture and translocation of problem martens.

Since the genetic basis for Down syndrome (DS) was described, understanding the causative relationship between genes at dosage imbalance and phenotypes associated with DS has been a principal goal of researchers studying trisomy 21 (Ts21). Though inferences to the gene-phenotype relationship in humans have been made, evidence linking a specific gene or region to a particular congenital phenotype has been limited. To further understand the genetic basis for DS phenotypes, mouse models with three copies of human chromosome 21 (Hsa21) orthologs have been developed. Mouse models offer access to every tissue at each stage of development, opportunity to manipulate genetic content, and ability to precisely quantify phenotypes. Numerous approaches to recreate trisomic composition and analyze phenotypes similar to DS have resulted in diverse trisomic mouse models. A murine intraspecies comparative analysis of different genetic models of Ts21 and specific DS phenotypes reveals the complexity of trisomy and important considerations to understand the etiology of and strategies for amelioration or prevention of trisomic phenotypes. By analyzing individual phenotypes in different mouse models throughout development, such as neurologic, craniofacial, and cardiovascular abnormalities, greater insight into the gene-phenotype relationship has been demonstrated. In this review we discuss how phenotype-based comparisons between DS mouse models have been useful in analyzing the relationship of trisomy and DS phenotypes.

We use data from three social groups of badgers (Meles meles) to illustrate how faecal DNA genotyping could be used in scent-marking studies. Faecal samples collected from latrines were genotyped to determine the individual identity and sex of badgers engaging in terri- torial behaviour and the frequency with which those individuals defecated at particular latrines. The method is potentially applicable to other species of carnivores that use latrines to mark their territories.

Phenological patterns in tropical plants usually are associated with the clear seasonality of rainfall associated with very different wet and dry seasons. In southern Brazil, in a subtropical forest with no pronounced dry season (average annual precipitation = 1389 mm, minimum monthly average c. 75 mm), plant phenology was studied to test for patterns (periodicity), to examine how phenological patterns vary among life-forms, and to test whether phenological cycles are associated with climatic variables. Thirty-seven plant species in four life-forms (trees, shrubs, lianas and epiphytes) were studied for 2 yr (1996-98) in an Araucaria forest remnant in southern Brazil, in the state of Parana. Correlation and multiple regression methods established relationships between phenology and climate in terms of daylength, temperature and rainfall. In this Araucaria forest, plants showed seasonality in most life-forms and phenological phases. Leaf-fall, with its peak during the drier months (April to July), was the most seasonal. Flushing and flowering occurred during the wetter months (September to December), while fruiting occurred all year long. Phenologies varied among life-forms, and were strongly associated with daylength or temperature of preceding months, suggesting that plants receive their phenological cues well in advance of their phenological response. Phenologies in this Araucaria forest appear to be associated with the most predictable and highly correlated of the climatic variables, daylength and temperature and least so with rainfall, which is unpredictable.

Eusocial insects, such as ants and termites, have distinct ‘castes’ specialized for carrying out different tasks. Eusociality is extremely rare in mammals, and in the few species that do show it, there has been no clear evidence that the helpers are a distinct caste. Now in an experiment that measured energy expenditure in workers of a eusocial mole-rat, two distinct castes have been identified. ‘Frequent workers’ labour year-round helping to sustain the colony and allowing the queen to breed. ‘Infrequent workers’ accumulate body fat, do little work, and await suitable opportunities to disperse and reproduce. After rainfall the fat lazy caste becomes extremely active and expends more energy than the frequent workers. The Damaraland mole-rat (Cryptomys damarensis) is the first eusocial mammal for which physiologically distinct castes have been found. Eusociality, which occurs among mammals only in two species of African mole-rat, is characterized by division of labour between morphologically distinct ‘castes’1. In Damaraland mole-rats (Cryptomys damarensis), colony labour is divided between ‘infrequent worker’ and ‘frequent worker’ castes2. Frequent workers are active year-round and together perform more than 95% of the total work of the colony, whereas infrequent workers typically perform less than 5% of the total work3. Anecdotal evidence suggests that infrequent workers may act as dispersers, with dispersal being limited to comparatively rare periods when the soil is softened by moisture4,5. Here we show that infrequent workers and queens increase their daily energy expenditure after rainfall whereas frequent workers do not. Infrequent workers are also fatter than frequent workers. We suggest that infrequent workers constitute a physiologically distinct dispersing caste, the members of which, instead of contributing to the work of the colony and helping the queen to reproduce, build up their own body reserves in preparation for dispersal and reproduction when environmental conditions are suitable.

Background Pseudomonas aeruginosa encodes a putative topoisomerase with sequence similarity to the eukaryotic type IB topoisomerase from Vaccinia virus. Residues in the active site are conserved, notably Tyr292 which would be predicted to form the transient covalent bond to DNA. Results The gene encoding the P. aeruginosa topoisomerase I was cloned and expressed in E. coli. The enzyme relaxes supercoiled DNA, while a mutant containing a Tyr292 to Phe substitution at the active site was found to be catalytically inert. This is consistent with the role of Tyr in forming the covalent intermediate. Like Vaccinia topoisomerase, the P. aeruginosa topoisomerase relaxes DNA in the absence of ATP, but unlike Vaccinia topoisomerase, P. aeruginosa topoisomerase does not relax supercoiled DNA without MgCl2 present. In addition, high concentration of NaCl is not able to substitute for MgCl2 as seen for Vaccinia topoisomerase. A truncated derivative of the topoisomerase lacking residues 1–98 relaxes DNA, with both full length and truncated enzyme exhibiting equivalent requirements for divalent cations and the ability to relax DNA to completion, suggesting a shared domain organization. DNA-binding assays suggest an only modest preference for the CCCTT pentameric sequence required for transesterification by Vaccinia topoisomerase IB. Conclusion P. aeruginosa encodes a functional topoisomerase with significant similarity to the type IB enzyme encoded by poxviruses. In contrast to the Vaccinia-encoded homolog, the P. aeruginosa-encoded enzyme requires divalent cations for catalytic activity, relaxes DNA to completion, and does not exhibit a strong preference for the pentameric sequence stringently required by the Vaccinia-encoded homolog. A comparison with the structure of poxviral topoisomerase in complex with DNA suggests that bacterial homologs of the eukaryotic type IB topoisomerase may exhibit a relaxed sequence preference due to the lack of conservation of certain residues involved in sequence-specific DNA contacts, and that interaction with an only modestly preferred sequence may result in suboptimal positioning of catalytic residues.

Computer generated discharge summaries are gaining in popularity. A simple and flexible method for generating neonatal summaries using commercially available software is described.

Large-scale field trials have been under way to assess how effective badger culls are in stemming the incidence of tuberculosis in cattle. One culling tactic, it seems, increases occurrence of the disease.

Background Modern approaches to treating genetic disorders, cancers and even epidemics rely on a detailed understanding of the underlying gene signaling network. Previous work has used time series microarray data to infer gene signaling networks given a large number of accurate time series samples. Microarray data available for many biological experiments is limited to a small number of arrays with little or no time series guarantees. When several samples are averaged to examine differences in mean value between a diseased and normal state, information from individual samples that could indicate a gene relationship can be lost. Results Asynchronous Inference of Regulatory Networks (AIRnet) provides gene signaling network inference using more practical assumptions about the microarray data. By learning correlation patterns for the changes in microarray values from all pairs of samples, accurate network reconstructions can be performed with data that is normally available in microarray experiments. Conclusions By focussing on the changes between microarray samples, instead of absolute values, increased information can be gleaned from expression data.

Referring to Zaidi et al's paper (Eye 2004; 18: 503–508), Marc Amsler was emphatic that his charts are to be used as a white grid on a black background. My own experience has confirmed that defects are much more easily picked up in this way. A pad of recording charts was included as a convenience but not as an alternative. Which charts were the patients given to use at home?

Falk (1961) showed that when rats were allowed to earn food pellets intermittently, in the presence of a water source, they developed the habit of drinking a small amount of water within each interpellet in­ terval. Because it dramatically enhances the rat's water intake, this type of drinking has become known as "schedule-induced polydipsia," or SIP. Two de­ cades of research have revealed SIP to be an extraor­ dinarily reliable effect, by behavioral standards, and have produced a wealth of experimental results and of conflicting theoretical accounts (see reviews by Falk, 1971,1977, and Staddon, 1977). Nevertheless, no satisfactory explanation of the rat's enhanced drinking under intermittent schedules of food avail­ ability has yet emerged. We have chosen to address the problem of SIP obliquely, by asking whether the phenomenon of schedule induction extends to activities other than drinking, to reinforcers other than food, and to spe­ cies other than the rat. In this way, we hope to de­ termine the extent to which SIP depends on special characteristics of the relationship between eating and drinking in the rat, as opposed to reflecting the operation of more general principles. We have re­ cently confirmed that wood-chewing can occur as a schedule-induced behavior in rats when food is in­ termittently available, and have shown that induced wood-chewing (like SIP) is inversely related to level of food deprivation (Roper & Crossland, 1982). This finding supports the idea that schedule indue

In Experiment 1, 12 rats were exposed to an FT 60 schedule of food reinforcement, followed either by extinction or by a massed-food control condition, in the presence of a wood block. In 9 rats, wood-chewing behavior increased systematically during the FT 60 condition and declined again during extinction or massed food, while the other 3 rats showed virtually no chewing behavior at any stage of the experiment. In Experiment 2, frequency and bout duration of wood-chewing under an FT 60 schedule of food reinforcement declined as body weight increased, in 7 rats. We conclude that wood-chewing qualifies as a schedule-induced behavior, and that it resembles schedule-induced drinking in its dependence on body weight. Unlike drinking, however, induced chewing occupied the middle region of the 60-sec interreinforcement interval, declined markedly within the session, and showed considerable within- and between-subject variability.

The term “schedule-induced” implies that the overall frequency of a behavior is greater in the presence of an intermittent schedule of reinforcement than in the absence of such a schedule. Consequently, the occurrence of interreinforcement behavior is not in itself sufficient evidence of schedule induction: a test of induction requires comparison between an intermittent-schedule condition and a nonschedule baseline. The relative merits of different types of nonschedule baseline are examined, and it is concluded that the best test of schedule-induction involves both an extinction and a massed-reinforcer baseline. A working definition of schedule-induction is suggested on this basis. Studies purporting to show schedule induction of activities other than drinking are critically reviewed, and it is concluded that schedule induction may be less general than is usually supposed. It may therefore be more fruitful to seek an explanation of schedule-induced drinking which focuses specifically on the interaction between food and water ingestion in the rat, rather than an explanation involving concepts such as stress, frustration, or arousal.