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The fertility announcement hypothesis proposes that avian males should sing at a high rate when their mate is fertile to guard their paternity. We examined if male Song Sparrows (Melospiza melodia) sing more during the incubation period when they are free of constraints of physical mate guarding. We assessed song rates of eight males for 1 hr-periods every 1-2 days during each breeding stage over two consecutive broods within one season. Males sang significantly more during periods when their mate was incubating than during the pre-fertile, or fertile periods, or while feeding young (second brood). Males may be singing at high rates during incubation to maintain contact with their mate and/or to advertise for extra-pair copulations., Song has two main functions, territory defense and mate attraction (Catchpole and Slater 1995). Song rate typically decreases after pairing (Catchpole and Slater 1995), but males of many species continue [...]

Studies of song and its function in suboscine passerines are rare. We examined spatial and temporal variation in song structure in a wild population of Olive-sided Flycatchers (Contopus cooperi) and tested among hypotheses explaining this variation. Repeatable variation in song type was observed both within and among individuals. More than 10% of territorial males expressed atypical song types, i.e., permutations of sequential missing and repeated elements of the typical adult song. Atypical songs were predominantly expressed by unpaired males independent of habitat type. A small fraction of males sang atypical song through the middle of the breeding season, but all males sang only stereotypical adult song by the end of the season. These results suggest the expression of atypical songs reflect protracted vocal development rather than evolution of new song types, geographic variation in song structure, or an extensive song repertoire in Olive-sided Flycatchers., Suboscines comprise ~20% (1,151 species) of the Order Passeriformes (Sibley and Monroe 1990), but studies of bird song and its functions have focused almost exclusively on oscines. Suboscines are characteristically [...]

We found nine nests of the Grey-hooded Parrotbill (Paradoxornis zappeyi) during April through July 2003 at Wawushan Natural Reserve, Sichuan, southwestern China. This report is the first description of the nest sites, nests, eggs, and breeding behavior of this parrothill, and the first documentation of nestling growth from hatching until fledging. The nests were constructed mainly of bamboo (Bashania faberi) leaves, fibrous roots, and moss by both male and female. Nests were bowl shaped and in bamboo thickets 81-122 cm above ground, and 17-68 cm below the top of bamboo leaves. Clutch size was 3.1 eggs (n = 8 nests) and eggs were oval, pale blue in color with a mean mass of 1.3 g. Incubation and provisioning of nestlings were by both parents. The nestling period was 13-14 days with a hatching rate of 0.52 and mean reproductive success rate of 0.48 fledglings per nest., The Grey-hooded Parrotbill (Paradoxornis zappeyi) is a rare Chinese endemic, one of five threatened members of a 10-species avian suite entirely restricted to the Central Sichuan Mountains Endemic Bird Area [...]

We studied breeding biology, parental roles, and social mating system of the Bay-capped Wren-Spinetail (Spartonoica maluroides), a habitat specialist furnariid, in the Argentinean pampas. We found 42 nests during 2004-2007, two during egg laying, 28 during incubation, and 12 with nestlings. Mean clutch size was 3.17 eggs (n = 29), the incubation period was 13 days, and nestlings remained in the nest for 12 days before fledgling. Bay-capped Wren-Spinetails are socially monogamous; both males and females develop a brood patch and contribute to incubation, brooding, and provisioning of nestlings. Wren-Spinetails are unique among furnariids as they build an open cup nest with a few presenting a loose domed roof. Breeding success of Bay-capped Wren-Spinetails was higher (total probability of nesting success = 0.508) than other species of sympatric passerines because of low nest predation and high nest survival rates during incubation and nestling rearing stages., The members of the Furnariidae (236 described species) inhabit a great diversity of biomes in the Neotropics, including lowland and montane forests, grasslands, salt and fresh water marshes, and rocky [...]

We studied the breeding biology of Purple Swamphens (Porphyrio porphyrio poliocephalus) at Nainar Pond in Tirunelveli, South India from January 2003 to May 2004. Peak breeding activity occurred from the second week of January to the first week of March. Nests were built on thick floating vegetation closest to the bank of the pond. Nesting material consisted of whole plants, stems, and leaves of Eichhornia crassipes, Jussieua repens, Pistia stratiotes, Ipomoea aquatica, and Cyperus rotundus with E. crassipes being most preferred. Nest dimensions were variable. Clutch size varied from three to seven eggs with a mean ([+ or -] SD) clutch size of 4.5 [+ or -] 1.5 and a model clutch size of four eggs. Mean volume of all eggs was 32.3 [+ or -] 3.5 [cm.sup.3]. The length of the incubation period was estimated as 19.8 [+ or -] 1.2 days. Nest and egg hatching success were estimated as 80.0% and 61.1%, respectively, while overall fledging success was 42.0%., The Purple Swamphen (Porphyrio porphyrio) is a medium sized water bird (Ali 1981) which lives in marshes, lagoons, and reservoirs with appropriate vegetation cover and water depth. Undisturbed areas with [...]

We provide the first description of the nest, eggs, and nestlings of the Planalto Woodcreeper (Dendrocolaptes platyrostris), a secondary cavity-nester, based on three nests in natural cavities and 14 in nest boxes. Nests were found from October to January in 1997, 2006, and 2007 in the humid Chaco and Atlantic Forest of Argentina. Planalto Woodcreepers used natural cavities and nest boxes 40-60 cm deep with entrance diameters of 5-12 cm. They selected the deepest nest boxes available. Three or four white eggs were laid on a bed of bark flakes and incubated for 14-16 days. Newly hatched nestlings had pink skin with gray down, yellow mouth linings, and large whitish gape flanges. They opened their eyes when 6-7 days of age and fledged at 16-18 days. Nearly all nestlings were infested with botflies (Philornis sp.). Both adults contributed to nest building, incubation, nestling-rearing, and nest sanitation., The woodcreepers are a group of cavity-nesting neotropical birds now recognized by many authors as members of the Furnariidae (Irestedt et al. 2002, 2006; Fjeldsa et al. 2005). They are [...]

The Northern Harrier (Circus cyaneus) is of major conservation and management concern in the northeastern United States. We studied habitat use of foraging adult male and female harriers on Nantucket Island, Massachusetts among four habitat types: grassland, shrubland, mowed, and burned. Overall, foraging indices were not correlated to nest proximity and harriers foraged significantly less frequently in mowed habitat than in the other habitat types. Management of harrier habitat in the northeastern United States may not exclusively require grasslands, and mowing reduces foraging habitat., Northern Harriers (Circus cyaneus) have been identified as a species of national concern by the U.S. Fish and Wildlife Service (USDI 2002), and populations have declined dramatically along the east [...]

ABSTRACT.--Blackwater National Wildlife Refuge on the Delmarva Peninsula, Maryland, USA has been the wintering area of a small population of Lesser Snow Geese (Chen caerulescens caerulescens; LSGO) since the 1930s. Snow Geese primarily pair in wintering areas and gene flow could be restricted between this and other LSGO wintering populations. Winter pair formation also could facilitate interbreeding with sympatric but morphologically differentiated Greater Snow Geese (C. c. atlantica; GSGO).We sequenced 658 bp of the mitochondrial DNA control region for 68 Snow Geese from East Coast and Louisiana wintering populations to examine the level of genetic differentiation among populations and subspecies. We found no evidence for genetic differentiation between LSGO populations but, consistent with morphological differences, LSGO and GSGO were significantly differentiated. We also found a lack of genetic differentiation between different LSGO morphotypes from Louisiana. We examined available banding data and found the breeding range of Delmarva LSGO overlaps extensively with LSGO that winter in Louisiana, and documented movements between wintering populations. Our results suggest the Delmarva population of LSGO is not a unique population unit apart from Mid-Continent Snow Geese., A small population of Lesser Snow Geese (Chen caerulescens caerulescens; LSGO) has been wintering on the Delmarva Peninsula on the east coast of the United States, mostly at Blackwater National [...]

Songs of individual male Blue Grosbeaks (Passerina caerulea) typically begin with the same combination of elements, but the sequence and number of elements in the latter portion of songs vary. We examined the possible functions of within-song variation in Blue Grosbeaks at the Blue Grass Army Depot near Richmond, Kentucky, USA from 15 April to 31 July 2007. We examined singing rates and song characteristics of second-year (SY; n = 6) and after-second-year (ASY; n = 14) males, and conducted playback experiments (n = 15) to identify the possible function of variation in song length. Male Blue Grosbeaks sang at highest rates prior to pairing, maintained relatively high singing rates during the post-pairing/pre-nesting and nest-building/egg-laying stages, and sang at lower rates during the incubation, nestling, and fledgling stages. These results suggest high singing rates are important in attracting mates and establishing territories, and lower singing rates may result from trade-offs associated with parental care. Males used longer songs during aggressive encounters with conspecifics and responded more aggressively to playback of longer songs. This suggests songs containing more elements signal increased aggression. Within-song variation may be an important way to vary song meaning for male Blue Grosbeaks, and perhaps other males in species with a single song type but repertoires of several different song elements., Singing by male songbirds serves a variety of functions, ranging from establishing territories and attracting mates (Smith 1991) to distracting predators (Ritchison 1991), communicating with young (Beecher 1990), coordinating nest [...]

We examined the complex of populations of the Loggerhead Kingbird (Tyrannus caudifasciatus), a West Indian endemic. We separate populations in Puerto Rico and Isla Vieques (T. taylori), and Hispaniola (T. gabbii) as distinct species. Subspecific distinction is assigned to populations in Cuba, Isla de Pinos, and Cuban satellites (T. caudifasciatus caudifasciatus); Cayman Islands (T. c. caymanensis); Jamaica (T. c. jamaicensis); and the Bahamas (T. c. bahamensis) on the basis of differences in plumage coloration and pattern, size, vocalizations, and distribution., The Loggerhead Kingbird (Tyrannus caudifasciatus) is endemic to the Bahama Islands and Greater Antilles, although occasionally stragglers have been reported in southern Florida (Bond 1978:3, Robertson and Woolfenden 1992, AOU [...]

Scoter vocalizations may have a role in pair formation and pair bonding. I compared the courtship calls of male Black Scorers (Melanitta nigra nigra and M. n. americana) using published and archived recordings. Courtship calls of the two subspecies differed diagnosably in duration. In contrast, recordings from different localities within the ranges of each taxon showed no diagnosable differentiation. This finding represents the first indication these taxa differ in characters other than bill morphology and supports recent proposals to treat M. n. americana as a distinct species (M. americana). Vocal displays, in contrast to courtship displays, of anatids have not been used for assessment of species limits in Anatidae. My results indicate vocalizations are a potentially useful additional character in species-level taxonomy of anatids., Courtship displays of anatids have attracted substantial attention from behavioral scientists (e.g., Heinroth 1911, Lorenz 1951-1953, Johnsgard 1965), and interspecific variation has been analysed and interpreted in an evolutionary context [...]

Northern Bobwhite (Colinus virginianus) populations have been declining throughout their range, but some of the sharpest declines have been documented in the Mid-Atlantic states. We conducted a 2 year (2006-2007) breeding season (1 May-30 Sep) telemetry study in southern New Jersey to collect baseline data on Northern Bobwhite reproductive rates, and nest and brood microhabitat selection. We located 23 Northern Bobwhite nests, of which 21 were usable for survival analyses. Incubation-period nest survival rate was 0.454 [+ or -] 0.010 (95% CI = 0.280-0.727). Mean clutch size was 14.2 [+ or -] 0.58 (range 10-19, n = 20) and hatching success was 96.1 [+ or -] 2.0% (range 86-100%, n = 10). The estimated probability that an individual that entered the breeding season would initiate incubation of [greater than or equal to] 1 nest was 0.687 for females and 0.202 for males. Nest microhabitat selection was positively related to visual obstruction and percentage of litter. Brood microhabitat selection was positively related to visual obstruction, vegetation height, and percentage of forbs but negatively related to percentage of cool season grass and litter. Fecundity metrics for Northern Bobwhites in southern New Jersey appear similar to those reported elsewhere in the species' range. Conservation efforts to increase Northern Bobwhite reproductive success in southern New Jersey should focus on increasing the quantity of available breeding habitat., Northern Bobwhite (Colinus virginianus) populations have been declining throughout most of their range (Sauer et al. 2008). Some of the most marked declines in Northern Bobwhite populations are occurring at [...]

Previous work has shown that purified double mutant A204C/C374A yeast actin is polymerization-deficient in vitro under physiological concentrations. To understand the importance of the 204 residue in subdomain 4, a series of actin proteins with a single mutation at this position were created with Cys-374 retained. Only yeast expressing A204G-, A204S-, or A204C-actin were viable. The A204G and A204S strains were sensitive to cold temperature and hyperosmolarity, whereas the A204C strain showed more profound effects on growth under these conditions. Cells expressing A204Cactin exhibited anomalies previously observed for A204C/C374A actin, including abnormal actin structures. A204G- and A204S-actin proteins had 12- and 13-fold increased critical concentrations, respectively, relative to wild-type. Only at very high concentrations could A204C actin polymerize when ATP was bound; when hydrolyzed, the ADP-containing A204C filaments depolymerized, demonstrating a profound difference in critical concentration between ATP and ADP states with A204C actin. A correlation between size of the residue substituted at position 204 and energy minimization of actin filament models was observed. We propose that the region surrounding residue 204 is involved in interactions that change depending on the phosphorylation state of the bound nucleotide that might reflect different conformations of F-actin subunits. Key words: actin polymerization, mutagenesis, critical concentration, nucleotide. Des travaux anterieurs ont montre que le double mutant purifie A204C/C374A de l'actine de levure possede un defaut de polymerisation in vitro sous des conditions physiologiques. Afin de comprendre l'importance du residu 204 du sous-domaine 4, une serie de proteines comportant une mutation ponctuelle a cette position ont ete produites, en conservant la Cys-374. Seules les levures exprimant les formes A204G, A204S ou A204C de l'actine etaient viables. Les souches A204G et A204S etaient sensibles au froid et a l'hyperosmolarite, alors que la souche A204C montrait des problemes de croissance plus prononces sous ces conditions. Les cellules exprimant l'actine A204C montraient des anomalies deja observe es chez les cellules exprimant la forme A204C/C374A, incluant des structures anormales d'actine. Les proteines A204G et A204S possedaient des concentrations critiques respectivement 12 et 13 fois superieures, relativement au type sauvage. L'actine A204C ne polymerisait qu'a tres haute concentration lorsque l'ATP etait liee; apres hydrolyse, les filaments d'actine A204C contenant l'ADP depolymerisaient, demontrant l'existence d'une difference importante dans les concentrations critiques des formes liees a l'ATP et a l'ADP de l'actine A204C. Une correlation entre la taille des residus substitues en position 204 et la minimisation d'energie des modeles de filaments d'actine a ete observee. Nous proposons que la region environnant le residu 204 est impliquee dans les interactions qui changent selon l'etat de phosphorylation du nucleotide lie, refletant possiblement differentes conformations des sous-unites d'actine. Mots-cles : polymerisation de l'actine, mutagenese, concentration critique, nucleotide. [Traduit par la Redaction], Introduction Actin is a 42 kDa cytoskeletal protein involved in a plethora of physiological processes. Polymerization into long filaments (F-actin) is a fundamental activity of the actin protein. F-actin can [...]

The two main types of theories for the evolution of the biphasic life cycles in marine invertebrates are discussed. The 'intercalation' theories propose that the larval stages (planktotrophic or lecithotrophic) have evolved as specializations from the ancestral, direct life cycle. The opposing 'terminal addition' theories propose that the ancestor was holopelagic and that the adult stage was added to the life cycle with the pelagic stage retained as a planktotrophic larva. It is emphasized that theories based on hypothetical ancestors that were unable to feed must be rejected. This applies to planula theories based on a compact planula. Various arguments against the theories that consider the feeding larvae as ancestral in the major eumetazoan lineages and in particular against the trochaea theory are discussed and found untenable. It is suggested that the 'Cambrian explosion' was actually a rapid Ediacaran radiation of the eubilaterians that was made possible by the evolution of a tubular gut with all the resulting possibilities for new body plans. We have irrefutable proof in support of the pelagic larval life as an original feature. ... This is so well documented that it would he superfluous to enter into the matter more closely, were it not for its great importance and the fact that there exist authors, who still assert that direct development is the original condition (Jagersten, 1972, p. 3)., Introduction In general, two main views have dominated recent discussions of animal life-cycle evolution, and specifically of that of the marine bilaterians. Either the ancestor was holopelagic (and therefore planktotrophic) [...]

Simultaneous hermaphrodites offer the chance to study antagonistic coevolution between the sexes when individuals function in both roles. Traumatic mating by hypodermic insemination has repeatedly evolved in hermaphroditic taxa, but evidence for the fitness costs of such male-advantage traits is lacking. When reared in isolation, specimens of the sea slug Alderia willowi (Opisthobranchia: Sacoglossa) initially laid clutches of unfertilized eggs but 4 days later began self-fertilizing; this is only the third report of selfing inan Alderia if penetration of the body wall bypasses internal mechanisms that promote outcrossing. Selfing specimens and slugs reared inpairs had reduced fecundity compared to isolated slugs laying unfertilized clutches, suggesting that hypodermic insemination imposes a cost of mating. Egg production increased for field-caught slugs separated after mating compared to slugs held in pairs, a further indication that accessibility to mates imposes a fitness cost to the female function. Such antagonism can confer a competitive advantage to slugs mating in the male role but diminish reproduction in the female role among hermaphrodites capable of long-term sperm storage. Alderia willowi is also a rare case of poecilogony, with adults producing either plankitotrophic or lecithotrophic larvae. Our rearing studies revealed that most slugs switched between expressed development models at some point; such reproductive flexibility within individuals is unprecedented, even among poecilogonous species., Introduction Sexually antagonistic traits that confer a male advantage are commonplace in animals (Rice, 1996; Partridge and Hurst, 1998; Arnqvist and Rowe, 2005). Physical features include genital armature and other [...]

Chemoautorophs that fix carbon by the reductive tricarboxylic acid cycle represent one of the dominant bacterial life forms that make a major contribution to bio-mass production. From the viewpoint of biogenesis, construction of a canonical chart of intermediary metabolism for this class of organisms may help us to understand early cellular evolution and point us to the last universal common ancestor. Data-mining the KEGG Pathways database enabled us to integrate required biosynthetic pathways and derive a chart that represents the complete anabolic network of a reductive chemoautotroph. Compounds of this metabolic network together constitute a representative minimal metabolome that comprises 287 metabolites. These compounds have been classified into different groups including those compounds that form nodes in the network. It can be seen that a relatively sparse set of organic chemical reactions dominate the anabolic synthesis in the assembly of the minimal autotrophic metabolome. Empirical generalizations that result from analyzing this metabolic network may aid in elucidating selection rules that govern its emergence and further evolution and may also help in delineating attributes that impart the observed robustness to these metabolites., Introduction Metabolic charts have been a central feature in the study of biochemistry since Donald Nicholson developed his first Metabolic Pathways Chart in 1955 (Nicholson, 2006). A printed version was [...]

Epizoochory is the mode of seed dispersal where a diaspore (disseminating plant propagule) is disseminated on the external surface of an animal. While the structures that facilitate diaspore adherence are diverse, epizoochory is considered to be relatively rare (approximately 10% of angiosperms), but is commonly utilized by several invasive plant species. We experimentally sought species specific associations between the adherence and retention of eight common plant species' diaspores and five mammalian furs, plus human clothing. We sought relationships between both fur and diaspore characteristics in both the adherence and retention of diaspores. Diaspores of Geum aleppicum were the only ones interacting significantly better with one kind of substrate (mouse fur) than diaspores of all other plant species by being retained well in mouse fur. Alternatively, bison fur behaved as a 'generalist' disperser, by consistently accommodating the adherence and retention of a wide range of diaspore morphologies. Finally, exotic plant species displayed a higher tendency than natives to adhere to a variety of mammal fur types, indicating a more flexible dispersal strategy for the invasive habit., INTRODUCTION Effective dispersal by plants is attained if propagules reach habitats favorable for survival, growth and reproduction (Stamp, 1989). Ridley (1930) recognized anemochory (dispersal by wind), hydroehory (dispersal by water) [...]

Exotic invasive plant species differ in their effects on indigenous vegetation as evidenced by research evaluating community response to their removal. We used a removal approach to quantify the response of a mesic woodland to the removal versus retention of an invasive plant, Hesperis matronalis (dame's rocket) from paired treatment plots over 3 y. Cover of H. matronalis did not differ between control and treatment plots prior to removal, declined in the removal plots and remained significantly lower in cover compared to the control plots. Removal did not significantly affect species richness and species diversity (evenness, Shannon and Simpson) at the plot scale, but did result in increased species richness overall in the removal plots in the last sampling year when compared to control plots. Non-metric multidimensional scaling ordination analysis indicated a significant compositional change in the spring plant composition of plots over the 3 y, reflecting an increase in exotic woody species. Exotic woody plants, especially Rosa multiflora and Euonymus alatus, increased in cover in response to H. matronalis removal. In the 3 y, neither native nor exotic forbs, nor native woody plants responded to the removal of H. matronalis in a statistically significant manner. The increasing cover of woody invasive plants in response to the removal of H. matronalis has important management implications for restoration of degraded communities., INTRODUCTION A major issue in prescribing management for control of exotic invasive plant species in disturbed or degraded natural areas is the potential response of the existing plant community to [...]

Because of the declines in grassland bird populations across North America, many state and federal agencies are making efforts to manage for grassland bird populations, particularly in a landscape context. To effectively manage for grassland birds, we need to understand how grassland bird species use different habitat types within landscapes. We determined the densities of grassland birds in remnant prairie patches and Conservation Reserve Program (CRP) fields and compared those to managed agricultural habitat types (pastures, alfalfa hay and strip crop fields). We also investigated whether densities were associated with landscape features. This study took place in the Military Ridge Prairie Heritage Area (MRPHA) in southwestern Wisconsin May-Jul. 2002 and 2003. Land use in the MRPHA is primarily agricultural, with a relatively large portion of the land in pasture, troy, small grains and idle grasslands enrolled in CRP and relatively few acres of corn and soybeans compared to other areas of the state. This area also has numerous remnant prairie patches. We used line transect surveys to measure species density in the different habitat types. The five most common grassland species in the study area were bobolink (Dolichonyx oryzivorus), eastern meadowlark (Sturnella magna), grasshopper sparrow (Ammodramus savannarum), Henslow's sparrow (A. henslowii) and Savannah sparrow (Passerculus sandwichensis). Densities did not differ between years. Habitat type was the most important factor associated with species density. Bobolink densities were greatest in hay fields, followed by CRP fields. Eastern meadowlark densities were greatest in CRP fields, remnant prairie patches and pastures. Grasshopper sparrow densities were greatest in remnant prairie, Henslow's sparrow densities were greatest in CRP fields and remnant prairie and Savannah sparrow densities were greatest in pasture and hay fields. There was no evidence that densities of any of the grassland species increased with site size within habitat type. Only bobolink and eastern meadowlark were associated with a landscape variable; both species' densities in the field were positively associated with proportion of grassland within 200 m of the site. When managing for grassland birds in a landscape with a large amount of grassland, a diversity of habitat types will be needed to conserve grassland birds as a group., INTRODUCTION In Wisconsin, 12 of 14 obligate grassland species (those that require open grasslands for breeding and do not require woody vegetation; Sample and Mossman [1997]) have shown significant declines [...]

Wildlife species can serve as biomonitors of environmental health and are prognostic of ecotoxicological consequences when contaminants are introduced into the environment. Small mammals, particularly rodents, comprise the majority of indicator species used in terrestrial biomonitoring studies; however, many biomonitoring studies address acute effects over relatively short periods. We still know little regarding effects of chronic exposure to contaminants on small mammals. The overall goal of this study was to determine ecological characteristics of small mammal communities inhabiting a heavy metal contaminated site, Tar Creek Superfund Site, compared to reference sites located in northeastern Oklahoma over a 2 y timeframe. Primary hazardous materials present at Tar Creek Superfund Site include lead, zinc and cadmium. Mark-recapture techniques were employed to test the hypothesis that structure and composition of small mammal communities inhabiting this contaminated site would be significantly altered compared to uncontaminated reference sites. Contaminated and reference sites were similar in vegetation compositional characteristics. Small mammal communities inhabiting Tar Creek Superfund Site had reduced species diversity, including richness and evenness, compared to reference sites. Furthermore, communities within Tar Creek Superfund Site were dominated by a single species, Peromyscus leucopus (white-footed mouse). Species composition was different between contaminated sites and reference sites as evidenced by detrended correspondence analysis, with contaminated sites being more similar to each other than to either reference site. No direct link between site contamination and disparities among most ecological characteristics could be established., INTRODUCTION Tar Creek Superfund Site (TCSFS), in Ottawa Co., Oklahoma, is one of three superfund sites located in the Tri-State Mining District, an 800 [km.sup.2] area extending into portions of [...]

The Indian Himalayas, being semi-isolated geographically, provide ideal conditions for population genetics investigations. The main aim of this study is to genetically characterize and analyze the genetic structure of the people of Uttarakhand, a newly created North Indian hill state in the Central Himalayas, using original phenotype and allele-frequency data on a battery of seven red cell enzyme polymorphisms. For this analysis, blood samples were collected from 3,222 unrelated subjects belonging to various endogamous caste populations (Brahmin, Rajput, and Shilpkar) and tribal Bhotia inhabiting seven different districts in the Garhwal (northern) and Kumaon (southern) regions of Uttarakhand. Hemolysates were typed for isozymes of ESD, PGM1, ADA, AK1, GLO1, ACP1, and GPI using standard electrophoretic techniques. The genetic structure of these regional caste and tribal population groups was investigated with the help of different statistical measures. The present biochemical marker results show that the overall genetic constitution of the different populations of Uttarakhand is rather heterogeneous but similar to that of various caste and tribal populations of the neighboring hill state of Himachal Pradesh, situated on Uttarakhand's western border. The extent of genic differentiation observed in different contemporary populations of Garhwal was twice as high as that of Kumaon. Interestingly, in genetic distance dendrograms of both the regions and of all of Uttarakhand, all the Shilpkar groups are differentiated from the remaining groups of Brahmin, Rajput, and Bhotia. The genetic constitution of the Shilpkar (a scheduled caste population of Uttarakhand) and to a lesser extent that of the Bhotia (a scheduled tribe population of Uttarakhand) are rather different from both the Brahmin and Rajput high-caste populations, which tend to show genetic similarities between them. These observations are corroborated by the known ethnohistory of different populations of Uttarakhand. KEY WORDS: RED CELL ENZYME POLYMORPHISMS, ESD, PGM1, ADA, AK1, GLO1, ACP1, GPI, CASTE POPULATIONS, TRIBAL POPULATIONS, UTTARAKHAND, CENTRAL HIMALAYAS., Anthropologically, the people of India, numbering over 1 billion, exhibit not only a wide variety of ethnic elements but also great cultural and linguistic diversity. The hierarchical caste system that [...]

Currently, language and cultural practices are the only criteria to distinguish between Berber autochthonous Tunisian populations. To evaluate these populations' possible genetic structure and differentiation, we have analyzed 15 autosomal short tandem repeat loci (CSF1PO, D3S1358, D5S818, D7S820, D8S1179, D13S317, D16S539, D18S51, D21S11, FGA, TH01, TPOX, VWA, D2S1338, and D19S433) in three southern Tunisian Berber groups: Sened, Matmata, and Chenini-Douiret. The exact test of population differentiation based on allele frequencies at the 15 loci shows significant P values at 7 loci between Chenini-Douiret and both Sened and Matmata, whereas just 5 loci show significant P values between Sened and Matmata. Comparative analyses between the three Berber groups based on genetic distances show that P values for [F.sub.ST] distances are significant between the three Berber groups. Population analysis performed using Structure shows a clear differentiation between these Berber groups, with strong genetic isolation of Chenini-Douiret. These results confirm at the autosomal level the high degree of heterogeneity of Tunisian Berber populations that had been previously reported for uniparental markers. KEY WORDS: STR, CSF1PO, D3S1358, D5S818, D7S820, D8S1179, D13S317, D16S539, D18S51, D21S11, FGA, TH01, TPOX, VWA, D2S1338, D19S433, BERBERS, POPULATION STRUCTURE, TUNISIA, NORTH AFRICA., Tunisian history records many and diverse population settlements. Tunisia was invaded from the first millennium b.c. until the 7th century A.D. by Phoenicians, Romans, Vandals, and Byzantines. These incursions seem [...]

Abstract: Estrogen plays an important role in skeletal physiology by maintaining a remodeling balance between the activity of osteoblasts and osteoclasts. In an attempt to decipher the mechanism through which [...]

Abstract: Staurosporine, a protein kinase C (PKC) inhibitor, has been reported to regulate the phosphorylation of ERK1/2 in several cell lines. It is still unknown, however, whether its derivative staurosporine [...]

Abstract: In vivo fatty acid synthesis and the pathways of glycerol-3-phosphate (G3P) production were investigated in brown adipose tissue (BAT) from rats fed a cafeteria diet for 3 weeks. In [...]

Interest in the relationships between soil microbial communities and ecosystem functions is growing with increasing recognition of the key roles microorganisms play in a variety of ecosystems. With a wealth of microbial methods now available, selecting the most appropriate method can be daunting, especially to those new to the field of microbial ecology. In this review, we highlight those methods currently used and most applicable to ecological studies, including assays to study various aspects of the carbon and nitrogen cycles (e.g., pool dilution, acetylene reduction, enzyme analyses, among others), methods to assess microbial community composition (e.g., phospholipid fatty acid analysis (PLFA), denaturing gradient gel electrophoresis (DGGE), terminal restriction fragment length polymorphism analysis (TRFLP), quantitative polymerase chain reaction (qPCR)) and methods to directly link community structure to function (e.g., stable isotope probing (SIP)). In our discussion of these methods, we describe the information each method provides, as well as some of their strengths and weaknesses. Using a case study, we illustrate how these methods can be applied to investigate relationships between microbial communities and the processes they perform in wetland ecosystems. We end our discussion with a series of questions to consider prior to designing experiments, in the hope that these questions will help guide ecologists in selecting the most appropriate method(s) for their research., INTRODUCTION Over the past 20 y, the variety of methods available to ecosystem and microbial ecologists has dramatically increased. At the same time, interest in soil microorganisms and the ecosystem [...]

Abstract: Taylorella asinigenitalis sp. nov is a nonpathogenic gram-negative bacterium recently isolated from the genital tract of male donkeys. The bacterium is phenotypically indistinguishable from Taylorella equigenitalis, a pathogen that [...]

We studied substrate composition and vegetation cover at Piping Plover (Charadrius melodusl nests and paired random plots on New York beaches that had been widened by renourishment (deposition of dredged sand). Most nests (59.4%, n = 32) were in unvegetated plots, mean ± SE vegetative cover around nests was 7.5 ± 1.7%, and all plovers nested in, Piping Plovers (Charadrius melodus) selecting nest sites on Atlantic Coast beaches must balance the risks of tidal flooding and egg predation (Burger 1987). They scrape nests in bare or sparsely-vegetated [...]

The academic success of students in introductory science courses is influenced by a variety of factors, the most important of which is academic motivation (Moore, 2005, 2006, 2007; Thomas & [...]

Abstract: It is well known that standard peptides, which comprise proteinogenic amino acids, can act as specific chemical probes to target proteins with high affinity. Despite this fact, a number [...]

Byline: Emiko Naito (Division of Biomodeling, Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Japan); Tsuyoshi Watanabe (Division of Biomodeling, Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Japan); Hajime [...]

Byline: J. Stehlik (Institute of Entomology, Biology Centre AS CR, Ceske Budejovice, Czech Republic, Faculty of Science, University of South Bohemia, Ceske Budejovice, Czech Republic); R. Zavodska (Institute of Entomology, [...]

Abstract: Cardiolipin (CL) is a major mitochondrial membrane phospholipid in the mammalian heart and the remodeling of CL is essential to maintain its unique unsaturated fatty acyl composition. We examined [...]

Abstract: Although home-based cardiac rehabilitation (CR) programs have been shown to produce significant increases in exercise capacity, obtaining patient adherence to these programs has been challenging. It is therefore critical [...]

Neuroecology unifies principles from diverse disciplines, scaling from biophysical properties of nerve and muscle cells to community-wide impacts of trophic interactions. Here, these principles are used as a common fabric, woven from threads of chemosensory physiology, behavior, and population and community ecology. The 'keystone species' concept, for example, is seminal in ecological theory. It defines a species whose impacts on communities are far greater than would be predicted from its relative abundance and biomass. Similarly, neurotoxins could function in keystone roles. They are rare within natural habitats but exert strong effects on species interactions at multiple trophic levels. Effects of two guanidine alkaloids, tetrodotoxin (TTX) and saxitoxin (STX), coalesce neurobiological and ecological perspectives. These molecules compose some of the most potent natural poisons ever described, and they are introduced into communities by one, or only a few, host species. Functioning as voltage-gated sodium channel blockers for nerve and muscle cells, TTX and STX serve in chemical defense. When borrowed by resistant consumer species, however, they are used either in chemical defense against higher order predators or for chemical communication as chemosensory excitants. Cascading effects of the compounds profoundly impact community-wide attributes, including species compositions and rates of material exchange. Thus, a diverse array of physiological traits, expressed differentially across many species, renders TTX and STX fully functional as keystone molecules, with vast ecological consequences at multiple trophic levels., Introduction A wide range of critical ecological interactions are mediated by chemistry. Biological responses to environmental chemical stimuli abound. Sensory perception of chemical signals, for example, strongly influences predation (Nevitt [...]

Byline: Richard E. Herman (Nastech Pharmaceutical Company, Inc., Bothell, Washington); Ekaterina G. Makienko (Nastech Pharmaceutical Company, Inc., Bothell, Washington); Mary G. Prieve (Nastech Pharmaceutical Company, Inc., Bothell, Washington); Mark Fuller [...]

Protein-protein interactions are widely found in biological systems controlling diverse cellular events. Because these interactions are implicated in many diseases such as autoimmunity and cancer, regulation of protein-protein interactions provides [...]

Nicotinamide adenine dinucleotide synthetase (NadE) is an essential enzyme for bacterial pathogens and is thus a promising antibacterial target. It catalyzes the conversion of nicotinic acid adenine dinucleotide to nicotinamide [...]

Abstract Two major approaches have been used to model circadian clocks. Qualitative modeling, used prior to the recent wealth of detailed molecular knowledge, makes general predictions but cannot provide detailed [...]

Abstract Work-related operations requiring extended wake durations, night, or rotating shifts negatively affect worker neurobehavioral performance and health. These types of work schedules are required in many industries, including the [...]

Abstract Mathematical models of neurobehavioral function are useful both for understanding the underlying physiology and for predicting the effects of rest-activity-work schedules and interventions on neurobehavioral function. In a symposium [...]

Abstract In this article, we discuss mathematical models that address the control of sleep-wake behavior in the infant and adult rodent and a model that addresses changes in single-cell firing [...]

Abstract Adolescent eveningness is associated with age, parental monitoring, daytime sleepiness, sleep problems, moodiness, and the use of coffee. This study investigated the association between adolescent morningness-eveningness and psychopathology, substance [...]

Abstract The molecular clockwork of the rat suprachiasmatic nucleus, the site of the circadian clock, is affected by the photoperiod (Sumova et al., 2003). The aim of the present study [...]

Abstract The suprachiasmatic nucleus (SCN) in the hypothalamus is the site of the master circadian clock in mammals, a complex tissue composed of multiple, coupled, single-cell circadian oscillators. Mathematical modeling [...]

The ancient Mississippi River paddlefish, Polyodon spathula, has long been thought to use its oversized rostrum for excavation. Recent studies provide an entirely new interpretation for the function of the [...]

Abstract Inhibition of acetylcholinesterase (AChE), the key enzyme in the breakdown of acetylcholine, is considered as a promising strategy for the treatment of neurological disorders such as Alzheimer's disease, senile [...]

Abstract Time-dependent variations in clock gene expression have recently been observed in mouse hematopoietic cells, but the activity of these genes in human bone marrow (BM) has so far not [...]

Abstract A quantitative, physiology-based model of the ascending arousal system is developed, using continuum neuronal population modeling, which involves averaging properties such as firing rates across neurons in each population. [...]