Photosynthesis online

Online access to the Internet and the World Wide Web have become important for public awareness and for educating the world’s population, including its political leaders, students, researchers, teachers, and ordinary citizens seeking information. Relevant information on photosynthesis-related Web sites and other online locations is grouped into several categories: (1) group sites, (2) sites by subject, (3) individual researcher’s sites, (4) sites for educators and students, and (5) other useful sites.     

Monitoring Important Bird Areas in Africa: Towards a Sustainable and Scaleable System

The need for effective global monitoring of biodiversity is clearer than ever, but our measurements remain patchy and inadequate. In the biodiversity-rich tropics, a central problem is the sustainability of monitoring schemes. Locally-based, participatory approaches show promise in overcoming this problem, but may not contribute effectively to monitoring at larger scales. BirdLife International’s framework for monitoring Important Bird Areas (IBAs) in Africa is designed to be simple, robust and locally-grounded, but to produce scaleable results that can be compiled into national or regional indices. Focusing on key sites for bird conservation, identified according to standard criteria, the framework institutionalises monitoring in site management authorities and Site Support Groups (community-based organisations of local people working for conservation and sustainable development). A small, central monitoring unit co-ordinates the programme nationally, compiles, analyses and manages data, and provides feedback. ‘Basic’ monitoring (taking place at all sites) involves scoring of state, pressure and response trends using site information submitted on simple forms. ‘Detailed’ monitoring (taking place at a selected sub-set of sites) involves more intensive measurement of particular variables that relate to site management targets. IBA monitoring is now underway in at least 10 African countries, with implementation of the framework most advanced (thanks to a pilot project) in Kenya. The 2004 IBA monitoring report for Kenya provides extensive information on individual IBAs, plus indices for national trends in state, pressure and response, based on data from 49 out of 60 sites. The experience in Kenya shows that institutionalisation is vital, but takes considerable time and effort; that adequate co-ordination (including timely feedback) is key; and that participatory monitoring has many valuable benefits beyond the data collected. Further work is being undertaken to refine the process, improve its scientific underpinning, and strengthen the feedback loop from data and analysis to action on the ground.     

Encoding of Time-varying Stimuli in Populations of Cultured Neurons

We wondered whether random populations of dissociated cultured cortical neurons, despite of their lack of structure and/or regional specialization, are capable of modulating their neural activity as the effect of a time-varying stimulation – a simulated ‘sensory’ afference. More specifically, we used localized low-frequency, non-periodic trains of stimuli to simulate sensory afferences, and asked how much information about the original trains of stimuli could be extracted from the neural activity recorded at the different sites. Furthermore, motivated by the results of studies performed both in vivo and in vitro on different preparations, which suggested that isolated spikes and bursts may play different roles in coding time-varying signals, we explored the amount of such ‘sensory’ information that could be associated to these different firing modes. Finally, we asked whether and how such ‘sensory’ information is transferred from the sites of stimulation (i.e., the ‘sensory’ areas), to the other regions of the neural populations. To do this we applied stimulus reconstruction techniques and information theoretic concepts that are typically used to investigate neural coding in sensory systems. Our main results are that (1) slow variations of the rate of stimulation are coded into isolated spikes and in the time of occurrence of bursts (but not in the bursts’ temporal structure); (2) increasing the rate of stimulation has the effect of increasing the proportion of isolated spikes in the average evoked response and their importance in coding for the stimuli; and, (3) the ability to recover the time course of the pattern of stimulation is strongly related to the degree of functional connectivity between stimulation and recording sites. These observations parallel similar findings in intact nervous systems regarding the complementary roles of bursts and tonic spikes in encoding sensory information. Our results also have interesting implications in the field of neuro-robotic interfaces. In fact, the ability of populations of neurons to code information is a prerequisite for obtaining hybrid systems, in which neuronal populations are used to control external devices.     

Autumn migration of Montagu’s harriers Circus pygargus tracked by satellite telemetry

Although there is a general understanding of Montagu’s harriers migration routes and wintering areas, detailed information on the species’ migration is still lacking. However, improvements in satellite tracking technology in recent years, have enabled the study of medium-sized species by means of satellite telemetry. In 2006, ten adult Montagu’s harriers were fitted with satellite transmitters in northeastern Spain and tracked during their autumn migration to their wintering grounds in sub-Saharan Africa. The migration took between 10 and 30 days, and the end point was determined using breakpoint regressions. Whereas some birds had stopovers of more than a week, others stayed at the same site for only 1 or 2 days at the most. The tagged birds ultimately established at wintering grounds located along the border of Mauritania with Mali and Senegal, a distance of nearly 3000 km from the breeding sites. These sites are situated within a small range of latitudes (14° and 17°N), although distributed over a wider range of longitudes (−15°E and −4°E), with some birds occupying sites more than 1000 km apart. The distance covered in 1 day during the migration ranged between 93 and 219 km, with peaks of traveling speed of up to 65 km/h. Harriers were recorded traveling only during daytime, covering the longest distances in the late afternoon, suggesting that they are daytime migrants. Most of the distance was covered between 1500 and 2000 hours, and no traveling was recorded between 2000 and 0500 hours. During migration, harriers flew close to the ground (40–100 m on average). Improved knowledge of the harriers’ exact wintering sites may provide insights on the problems Montagu’s harriers face during the winter, highlighting the need to take into account what happens in both the breeding and wintering grounds to implement successful conservation measures.     

Distribution and abundance of Wilson’s storm petrels Oceanites oceanicus at two locations in East Antarctica: testing habitat selection models

Over the last decades, Antarctic seabird populations have been studied as bioindicators of the variability in the Southern Ocean marine ecosystem. Little information is available on the distribution and abundance of Wilson’s storm petrel (Oceanites oceanicus) in East Antarctica although the bioindicator value of this species has been investigated. Regional surveys were conducted at two coastal locations, Casey (66°S, 110°E) and Mawson (67°S, 62°E), to locate Wilson’s storm petrel nests using systematic searches in sites selected with a balanced random sampling design. Conducted in ice-free areas of similar size, searches located 553 Wilson’s storm petrel nests at Mawson and 630 at Casey. Comparable densities were observed between locations but regional estimates suggest that Wilson’s storm petrels are more abundant at Casey. Habitat preferences of Wilson’s storm petrels were investigated using resource selection functions based on Generalized Additive and Linear Models (GAMs and GLMs), which allow their ecological niche to be graphically and quantitatively described. The orientation of nests in relation to the prevailing winds was identified as a determinant of nest distribution at both locations. However, selected rock substrate types differed between Mawson and Casey. Snow was confirmed to constrain the spatial distribution of nests, especially at Casey where snow precipitations and accumulation are more common in summer, confirming the results of previous temporal surveys focusing on breeding success. At the southern edge of its geographic distribution, the Wilson’s storm petrel may be subject to more obvious climate related habitat changes in East Antarctica. Such models may provide valuable information to detect the potential effect of climate variations on this species and others, in the context of a broad Antarctic ecosystem monitoring.     

Factors affecting the local occurrence of the near-threatened bitterling (<Emphasis Type="Italic">Tanakia lanceolata</Emphasis>) in agricultural canal networks: strong attachment to its potential host mussels

Ecologically specialized species may be more susceptible to anthropogenic impacts than generalist species. Japan’s native bitterlings (subfamily Acheilognathinae), which are specialized to spawn on the gills of certain freshwater mussels, have been declining dramatically during the last few decades. To identify factors affecting the local occurrence of the threatened bitterling species Tanakia lanceolata, we measured its presence and absence, along with several environmental factors, at 68 sites within agricultural canal networks in the Lake Mikata basin, Fukui Prefecture, Japan. Based on the theoretical information approach of Akaike’s information criterion, generalized linear mixed models were constructed. These revealed that the species’ occurrence is strongly affected by five major factors: the presence of freshwater mussels Anodonta sp., water depth, floating plants coverage, the presence of bullfrogs, and submerged plants coverage. The probability of the presence of T. lanceolata was higher at shallower sites with lower floating plants coverage, located within channels containing mussel beds. These results suggest that mussel-containing channel systems are high-priority conservation zones for T. lanceolata.     

Willingness to engage in casual sex

Sexually dimorphic mate selection strategies were examined in 200 university students reporting their willingness to engage in casual sexual encounters with hypothetical individuals of the opposite sex. Using a questionnaire format, the possibility of forming a long-term relationship was manipulated, while risk of disease, pregnancy, and detection was eliminated across all conditions. In addition, potential partners varied in level of attractiveness, and in personality and behavioral characteristics. As expected, men reported a greater anticipated willingness to engage in sexual intercourse across all conditions compared with women. The possibility of forming a long-term relationship elevated women’s, but not men’s, willingness for sexual intercourse. While a potential partner’s attractiveness had a significant positive overall effect on responses, reducing their relative attractiveness had a greater negative impact on men’s responses. Reference to the parental qualities of a potential partner significantly increased women’s, but not men’s, anticipated willingness for sexual intercourse. Describing a hypothetical partner as non-aggressive (safe) marginally increased women’s willingness (p<.09) and did not affect men’s responses. The wording of items relevant to this condition may have resulted in the potential partner sounding "wimpy" rather than nonaggressive, and this may have reduced the expected effect of this manipulation. The possibility that women may trade off personality and behavioral characteristics with attractiveness to a greater degree than men when assessing potential mates is considered.     

Characterization,Ecological Status and Type-specific Reference Conditions of Surface Water Bodies in Wallonia (Belgium) using Biocenotic Metrics based on Benthic Invertebrate Communities

The river types in Wallonia (Belgium) were defined according to the system B of the European Water Framework Directive (WFD) taking into account obligatory and optional factors synthesized in three criteria: ‘size’, ‘slope’ and ‘natural region’. Under the hypothesis that benthic invertebrate assemblages would be specialized according to river type, a set of 627 faunal samples originating from an 11-year sampling period was tested to characterize river types with faunal assemblages. A multivariate approach led to gather 23 river types into seven groups exhibiting similar faunal assemblages. Using biocenotic metrics based on benthic invertebrate assemblages (e.g., the French standard IBGN), type-specific reference conditions and ecological status class limits were defined for each ‘natural’ river type group. Ecological potential was defined for heavily modified and for artificial (i.e., man-made canals) types. An ‘ecological status’ evaluation strategy was therefore developed and applied in the southern – and more natural – part of Wallonia, where many reference sites were available. In the northern part of Wallonia (i.e., the ‘Loess region’) where no high quality site was available, the expert judgement took a larger part in the definition of the reference conditions and of the ecological status class limits, in addition to the calculations. Two independent distribution gradients of taxa assemblages resulted from multivariate ordination: a first ‘saprobity axis’, as the taxa-sensitivity to organic contamination was increasing from ‘very resistant’ taxa (mainly located in the ‘Loess region’) to ‘sensitive’ and ‘very sensitive’ taxa (from the river types belonging to the Condroz, the Famenne, the Arden and the Jurassic regions) and a second axis characterizing the Meuse-specific faunal assemblage, gathering exotic species and typical limnophilous taxa of large heavily modified rivers. The ecological status monitoring management system developed in this study – i.e., the definition of faunal river type groups, related reference conditions and ecological status class limits – represents a proposal to be integrated in the ecological status assessment of biological elements for the implementation of the WFD and was tested in Wallonia. For the period 2000–2002 involving 349 different sites, the element ‘benthic invertebrate fauna’ was in that way classified ‘high status’ for 31.5% of sites, ‘good status’ for 31.5% and below ‘good status’ for 37% of sites. The best ecological status (i.e., 100% ‘high’ and ‘good’ status) was found in river type ‘Arden’s xenotrophic brooks with strong slope’ and in river types 8large rivers with medium slope’. The worst status was found in river types ‘Loess brooks and rivers with medium slope’.     

“The Trust is Over! We Want to Plough!”: Social Differentiation and the Reversal of Resettlement in South Africa

In the early 1980s residents of Hobeni, in South Africa’s Eastern Cape, were subjected to forced resettlement, under “betterment” policy ostensibly aimed at soil conservation. They were moved into a spatially contiguous but socially differentiated village. South Africa’s political transition ended this policy, and in the early 1990s, some people, mainly from part of the resettlement area (Kunene) characterized by dense kinship networks who had faced pressure to leave, and began to return voluntarily to their former sites, opting to live in dispersed, flexible settlements. Few people resettled in Mhlanganisweni, a part of the village more diverse in its social composition, returned to their former sites. This research highlights the ways exclusion within “socially-embedded” land tenure systems, together with the layout of resettlement areas and other forms of social and economic differentiation, caused patterns of resettlement to diverge from planners’ intentions.     

Age-related changes of bone mineral density in human calcaneus, talus, and scaphoid bone

To examine whether the bone mineral density (BMD) decreases uniformly with aging in any spongy bones, the authors investigated age-related changes of BMD in the calcaneus, talus, and scaphoid bone. After the ordinary dissection by medical students was finished, calcanei, tali, and scaphoid bones were resected from the subjects, and BMDs were measured by dual-energy X-ray absorptiometry. Their BMDs seemed to decrease gradually with aging in the calcanei, tali, and scaphoid bones. It was found that there were statistically significant relationships between age and BMD in the men’s and women’s scaphoid bones, women’s tali, and women’s calcanei, but not in the men’s tali and calcanei. It should be noted that there were significant relationships between age and BMD in both men’s and women’s scaphoid bones. In regard to relationship in BMD between the bones of the upper and lower limbs in individuals, it was found that the relationship between the calcaneus and talus was higher than that between the calcaneus and scaphoid bone. This suggests that there is a higher relationship in BMD between the two tarsal bones compared with that between the tarsal and carpal bones.     

Words,antibodies and their interactions

Jerne’s idiotypic network theory stresses the importance of antibody-to-antibody interactions and provides possible explanations for self-tolerance and increased diversity in the immune repertoire. In this paper, we use an immune network model to build a user profile for adaptive information filtering. Antibody-to-antibody interactions in the profile’s network model correlations between words in text. The user profile has to be able to represent a user’s multiple interests and adapt to changes in them over time. This is a complex and dynamic engineering problem with clear analogies to the immune process of self-assertion. We present a series of experiments investigating the effect of term correlations on the user’s profile performance. The results show that term correlations can encode additional information, which has a positive effect on the profile’s ability to assess the relevance of documents to the user’s interests and to adapt to changes in them.     

Still More “Fancy” and “Myth” than “Fact” in Students’ Conceptions of Evolution

College students do not come to biological sciences classes, including biological anthropology, as “blank slates.” Rather, these students have complex and strongly held scientific misconceptions that often interfere with their ability to understand accurate explanations that are presented in class. Research indicates that a scientific misconception cannot be corrected by simply presenting accurate information; the misconception must be made explicit, and the student must decide for him or herself that it is inaccurate. The first step in helping to facilitate such conceptual change among college students is to understand the nature of the scientific misconceptions. We surveyed 547 undergraduate students at the University of Missouri-Columbia on their understanding of the nature and language of science, the mechanisms of evolution, and their support for both Lamarckian inheritance and teleological evolution. We found few significant sex differences among the respondents and identified some common themes in the students’ misconceptions. Our survey results show that student understanding of evolutionary processes is limited, even among students who accept the validity of biological evolution. We also found that confidence in one’s knowledge of science is not related to actual understanding. We advise instructors in biological anthropology courses to survey their students in order to identify the class-specific scientific misconceptions, and we urge faculty members to incorporate active learning strategies in their courses in order to facilitate conceptual change among the students.     

Amounts and patterns of nucleotide variation within and between two Japanese conifers, sugi (Cryptomeria japonica) and hinoki (Chamaecyparis obtusa) (Cupressaceae sensu lato)

Sugi (Cryptomeria japonica) and hinoki (Chamaecyparis obtusa) are the most important timber species in Japan. To quantify and compare the level of nucleotide variation in these species, we investigated their variation at ten nuclear loci. Average values of nucleotide diversity at synonymous sites (π _SYN) found in sugi and hinoki were 0.0038 and 0.0069, respectively. However, although the average value of nucleotide diversity was higher in hinoki than in sugi, their average values of haplotype diversity were similar. Deviations from the standard neutral model were detected at two loci in hinoki using Tajima’s D, Fay and Wu’s H, and Strobeck’s S statistics, which seem to be due to its historical population structure. Levels of divergence between the two species at synonymous sites of the ten genes ranged from 0.121 to 0.566 (0.28 on average). These values positively correlated with their guanine + cytosine contents at third-codon positions of synonymous sites (%GC3s).     

The role of herbivorous water birds in aquatic systems through interactions with aquatic macrophytes,with special reference to the Bewick’s Swan – Fennel Pondweed system

The role of aquatic macrophytes in stimulating biodiversity and maintaining clear waters is currently undisputed. The management of (eutrophic) shallow waters is therefore often directed at (re-)establishing macrophyte domination. In contrast, the role of water birds has long been considered of minor importance for the functioning of fresh water ecosystems. Indeed, in terms of biomass and production, water birds constitute only a minor part of these systems. However, water birds may graze heavily on water plants under certain circumstances, and the question arises whether herbivorous water birds have an important indirect effect on shallow fresh water systems. Mainly illustrated with the interaction between Bewick’s Swans and Fennel Pondweed, we present data on the role that water plants may play in the life of water birds and how water birds may impact water plants’ fitness in terms of survival, production, dispersal and competitive ability. It appears that water plants may be crucial for water birds during periods of high-energy requirements, such as migration. Despite the plants’ costs associated with water bird grazing, the interaction between water birds and water plants varies in nature from an apparent predator–prey relationship to a mutually beneficial interaction depending on the context and the perspective. For the case of the Bewick’s Swan–Fennel Pondweed interaction, regular bird grazing is sustainable and may actually favour the plant’s dispersal. Thus, Bewick’s Swans themselves may in fact play a crucial role in establishing and maintaining the Fennel Pondweed rich staging sites between the swans’ wintering and breeding grounds, which are vital for the swans’ successful migration.     

Genetic variability and differentiation of <Emphasis Type="Italic">Caragana microphylla</Emphasis> populations as revealed by RAPD markers

Genetic variability in random amplified polymorphic DNA (RAPD) was studied in 90 individuals of Caragana microphylla, an outcrossing perennial shrub species, from five natural populations sampled in Inner Mongolia steppe of China on a small scale. Nineteen selected primers were used to amplify DNA samples, and totally 225 bands were detected. The percentage of polymorphic bands within populations ranged form 58.22% to 63.56%, with an average of 60% at the population level and 71.11% at the species level, indicating relatively high genetic variations in C. microphylla species. Shannon’s information index (l) and Nei’s gene diversity (h) showed the similar trend with each other. According to the analysis of Nei’s gene diversity, the percentage of genetic variation among populations was 7.13%, indicating a low level of genetic differentiation among populations. There existed a strong gene flow (N _m = 3.26) among populations. Although AMOVA analysis also revealed most variation was within populations (Φ_ST = 4.1%), a significant proportion was observed among populations (P < 0.001) in the present study, suggesting genetic differentiation occurred among populations at a certain extent. Based on Mantel’s tests and the results of previous studies, the genetic structure pattern of C. microphylla accorded with the isolation-by-distance model on a very large scale, however, on a small scale, the significant genetic differentiation among populations might be enhanced by the micro-environmental divergence among the sampling sites, rather than by geographic factors. Analysis of the genetic variations of C. microphylla populations provided useful information for the adaptive strategy of Caragana species.     

Cyclic variation in women’s preferences for masculine traits

Women’s preferences for several male traits, including voices, change over the menstrual cycle, but the proximate causes of these changes are unknown. This paper explores relationships between levels of estradiol, progesterone, luteinizing hormone, follicle stimulating hormone, prolactin, and testosterone (estimated using menstrual cycle information) and women’s preferences for male vocal masculinity in normally cycling and hormonally contracepting heterosexual females. Preferences for vocal masculinity decreased with predicted progesterone levels and increased with predicted prolactin levels in normally cycling—but not hormonally contracepting—women. Adaptive explanations for menstrual variation in women’s preferences for masculine traits are discussed and evaluated in light of these findings.     

External radiation doses from <Superscript>137</Superscript>Cs to frog phantoms in a wetland area: in situ measurements and dose model calculations

For assessment of external radiation doses to frogs in a wetland area contaminated with ¹³⁷Cs, frog phantoms were constructed from polymethyl methacrylate (PMMA). The frog phantoms contained thermoluminescence (TL) chips and were used in situ at two study sites to measure doses. To test if higher doses are received by the sensitive skin of frogs, extra-thin TL chips were applied close to the surface of the frog phantoms. In addition, the measured doses were compared with those calculated on the basis of soil sample data from the wetland multiplied with dose-conversion coefficients from the US Department of Energy’s RESRAD-BIOTA code and from the ERICA assessment tool. Measured doses were generally lower than those calculated to ellipsoids used to model frogs. Higher doses were measured at the frog phantoms’ surfaces in comparison to inner parts at one of the two sites indicating that the frogs’ thin skin could receive a higher radiation dose than expected. In the efforts to assure protection of non-human biota, in situ measurements with phantoms provide valuable dose information and input to dose models in site-specific risk assessments of areas contaminated with radionuclides.     

Causes of mortality in a Geoffroy’s cat population—a long-term survey using diverse recording methods

We present quantitative data on the impact of different causes of mortality in a Geoffroy’s cat (Leopardus geoffroyi) population inhabiting a protected area and adjacent cattle ranches in central Argentina. Between December 2000 and January 2009, we used three methods to collect data on causes of mortality in both the park and the ranches: (1) information obtained from 35 radio-collared Geoffroy’s cats monitored from 1 to 19 months; (2) a systematic survey of the areas to find non-collared dead animals; and (3) interviews of qualified informants. Deaths of radio-collared individuals in the park were due to predation by puma (Puma concolor) or starvation, whereas deaths in the ranches were attributed to starvation and predation by domestic dogs. The death of eight emigrant cats was attributed mainly to poaching. Cause of death of 39 non-collared Geoffroy’s cats was determined; deaths in the ranches were mainly due to predation by domestic dogs and poaching, whereas deaths in the park were attributed to predation by puma, poaching, and vehicle collision. Grouping all sources of information, human-related mortality accounted for most (62%) of Geoffroy’s cat deaths recorded during this study, with poaching and predation by dogs being the main causes of mortality. This study in Geoffroy’s cats is the first long-term survey of causes of mortality for a population of a small felid species in South America.     

Binocular fusion in Panum’s limiting case of stereopsis obeys the uniqueness constraint

In the information processing procedure of stereo vision, the uniqueness constraint has been used as one of the constraints to solve the “correspondence problem”. While the uniqueness constraint is valid in most cases, whether it is still valid in some particular stimulus configuration (such as Panum’s limiting case) has been a problem of widespread debate for a long time. To investigate the problem, we adopted the Panum’s limiting case as its basic stimulus configuration, and delved into the phenomenon of binocular fusion from two distinct aspects: visual direction and orientation disparity. The results show that in Panum’s limiting case binocular fusion does not comply with the rules governing regular binocular fusion as far as visual direction and orientation disparity are concerned. This indicates that double fusion does not happen in Panum’s limiting case and that the uniqueness constraint is still valid.     

Binocular fusion in Panum’s limiting case of stereopsis obeys the uniqueness constraint

In the information processing procedure of stereo vision, the uniqueness constraint has been used as one of the constraints to solve the “correspondence problem”. While the uniqueness constraint is valid in most cases, whether it is still valid in some particular stimulus configuration (such as Panum’s limiting case) has been a problem of widespread debate for a long time. To investigate the problem, we adopted the Panum’s limiting case as its basic stimulus configuration, and delved into the phenomenon of binocular fusion from two distinct aspects: visual direction and orientation disparity. The results show that in Panum’s limiting case binocular fusion does not comply with the rules governing regular binocular fusion as far as visual direction and orientation disparity are concerned. This indicates that double fusion does not happen in Panum’s limiting case and that the uniqueness constraint is still valid.