From space to species: integrating remotely sensed information on primary productivity into investigations and systems models of vervet monkey (Cercopithecus aethiops) socio ecology

An in depth investigation of the socio-ecology of the vervet monkey species complex (Cercopithecus aethiops subspp.) is presented. Herein, particular emphasis has been placed on evaluating the information content of remotely sensed primary productivity with respect to inquiries into the causal network underlying the behavioural ecology of the species. The principal aim was to construct an inter-populational model of group size and range of distribution for vervet monkeys over the whole of sub-Saharan Africa. Data were collected on a habituated group of vervet monkeys over a 12 months observation period at the Lajuma Research Centre, South Africa. In addition, behavioural information from other populations was gathered in an extensive literature review. Environmental data were accrued on both a global (inter-populational) and local (intra- populational) level using a combination of remotely sensed data and more traditional field-observation based techniques. Where appropriate, variables were integrated into the powerful modelling environment of a Geographical Information System (GIS).Biologically intuitive associations between a remotely sensed index of primary productivity (the Normalised Difference Vegetation Index, or NDVI) and climatic conditions were established on the long-term global (annual average values over sub- Saharan Africa) and short-term local level (monthly values over the home range area of the study group). Local NDVI values, moreover, were strong correlates and predictors of field estimates on local phenology and food availability as well as of temporal and spatial variation in parameters of range use and time allocation by the study group. Global NDVI values proved pivotal to the eventual inter-populational time budget model of vervet monkey group size and potential range of distribution. Current results are taken to suggest that several areas of research within primatology may stand a lot to gain from a more widespread and systematic application of the powerful methodological synergism offered by remote sensing and geographical information systems

What Your Heart Doth Know

Combining embryological insight with careful analysis of early stage cardiomyocyte differentiation, Kattman et al. (2011) in this issue of Cell Stem Cell have defined minimal culture conditions to efficiently produce cardiomyocytes from hESCs and hiPSCs. The lessons learned are applicable to the derivation of other organotypic cell types

Determinants of Paternity Success in a Group of Captive Vervet Monkeys ( Chlorocebus aethiops sabaeus )

Paternity success of high-ranking primate males is affected by the number of males and the number of fertile females and their cycle synchrony. Female vervets in the wild show strong reproductive seasonality and do not advertise the ovulatory period with conspicuous signals or behavior. Because this makes it difficult for males to monopolize fertile females, it can be expected that male reproductive skew in this species is lower than in other cercopithecines living in multimale groups that advertise the ovulatory period. We assessed male reproductive success in a captive vervet group, initially consisting of 4 males and 12 unrelated females. Besides a general low reproductive skew, we predicted paternity success of the alpha males to be dependent on the overlap of synchronously fertile females, month into alpha male tenure, and housing conditions (the subjects were kept in a large park but had to be locked in a small indoor compartment during the winter months). Further, because the number of males reaching their prime increased over time, we predicted a decrease in reproductive success of the alpha male with increasing tenure length of the alpha male. To assess this we collected genetic samples from 27 of 32 offspring born into the group during 3yr, using 7 polymorphic human microsatellite markers. Contrary to our predictions, reproductive success of the males occupying the alpha position during the study was among the highest found in cercopithecines, with the alpha males siring 78% of all offspring. The degree of overlapping fertile periods did not affect paternity success, nor did paternity success of the alpha male differ between the 2 housing conditions. Only the alpha male's tenure length had an effect. Alpha male reproductive success decreased over time, which we attribute to either a shift in female mate choice toward younger males or to increased competition among the males in the later stage of the alpha male's tenure. This study demonstrates the importance of assessing reproductive success of males throughout >1 season and should spawn more research into the role of female choice and postcopulatory mechanisms in this specie

Behavior of post panamax vessels in the Third Set of Panama locks

Flanders Hydraulics Research built a 1/80 scale model in which three different ship models have been experimented to assess the navigation behavior in the Third Set of Panama locks. The radio controlled ship models were laterally restrained, equipped with an own propulsion and longitudinally assisted by simulated tugs. During the tests forces exerted on and vertical motions of the ship, as well as water levels were recorded. A limited number of tests included density currents, which mainly occur between the first lock chamber and the ocean side. All typical lock maneuvers have been tested at different approach wall configurations, eccentricities, propeller rates, approach scenarios and under keel clearances. This article presents a selection of results of interest for lock maneuvers, among which the significant effect of density currents and the approach wall configuration on the lateral forces that act on the entering and exiting vessels. Control of lateral forces by the ship’s controls and tug assistance is therefore a determining parameter

Inoculum selection influences the biochemical methane potential of agro-industrial substrates

Obtaining a reliable estimation of the methane potential of organic waste streams in anaerobic digestion, for which a biochemical methane potential (BMP) test is often used, is of high importance. Standardization of this BMP test is required to ensure inter-laboratory repeatability and accuracy of the BMP results. Therefore, guidelines were set out; yet, these do not provide sufficient information concerning origin of and the microbial community in the test inoculum. Here, the specific contribution of the methanogenic community on the BMP test results was evaluated. The biomethane potential of four different substrates (molasses, bio-refinery waste, liquid manure and high-rate activated sludge) was determined by means of four different inocula from full-scale anaerobic digestion plants. A significant effect of the selected inoculum on the BMP result was observed for two out of four substrates. This inoculum effect could be attributed to the abundance of methanogens and a potential inhibiting effect in the inoculum itself, demonstrating the importance of inoculum selection for BMP testing. We recommend the application of granular sludge as an inoculum, because of its higher methanogenic abundance and activity, and protection from bulk solutions, compared with other inocula

Cognitive differences between orang-utan species: a test of the cultural intelligence hypothesis

We also express our gratitude to the following foundations who have financially supported this project: A. H. Schultz Foundation, Paul Schiller Foundation and the Claraz Foundation in Switzerland and Waldemar von Frenckells Foundation, Ella and Georgh Ehrnrooths Foundation, Otto A. Malms Donationsfond, Nordenskiöld Samfundet and Oskar Öflunds Foundation in Finland.Cultural species can-or even prefer to-learn their skills from conspecifics. According to the cultural intelligence hypothesis, selection on underlying mechanisms not only improves this social learning ability but also the asocial (individual) learning ability. Thus, species with systematically richer opportunities to socially acquire knowledge and skills should over time evolve to become more intelligent. We experimentally compared the problem-solving ability of Sumatran orang-utans (Pongo abelii), which are sociable in the wild, with that of the closely related, but more solitary Bornean orang-utans (P. pygmaeus), under the homogeneous environmental conditions provided by zoos. Our results revealed that Sumatrans showed superior innate problem-solving skills to Borneans, and also showed greater inhibition and a more cautious and less rough exploration style. This pattern is consistent with the cultural intelligence hypothesis, which predicts that the more sociable of two sister species experienced stronger selection on cognitive mechanisms underlying learning.Publisher PDFPeer reviewe

Multi-year lactation and its consequences in Bornean orangutans ( Pongo pygmaeus wurmbii )

In most mammals, females pay for reproduction by dramatically increasing net energy intake from conception to mid- or late lactation. To do this, they time their reproductive events in relation to environmental cycles so that periods of peak food availability coincide with peak demand or are used to build energy stores. This timing is not possible in species with slow development in which lactation is prolonged over a multi-year period with fluctuating food availability. Here, mothers are expected to sustain a stable but generally lower level of nutrient transfer. In a sample of over 1,050 complete follow days of eight mother-infant pairs collected over 7years, we document maternal effort for wild Bornean orangutans (Pongo pygmaeus wurmbii) over their average 6.5-year lactation period. As predicted, maternal feeding time was independent of the age of her growing offspring, indicating a stable sustained "plateau” effort of ≤ 25% above baseline level, instead of a short peak lactation as seen in seasonal breeders. Infant orangutans started to regularly supplement milk with self-harvested food when they were 1-1.5years old, indicating milk intake was insufficient from this age onwards, even though maternal effort did not decrease. We expect the same regulation of sustained maternal effort in other large and large-brained mammals with slow infant development. We also predict that mother-infant conflict over suckling may show another peak at the onset of the milk + solid food phase, in addition to the well-known conflict around the endpoint of lactation (weaning), which is reached after a long and gradual increase in solid food intake by the infan

To drum or not to drum: Selectivity in tree buttress drumming by chimpanzees (Pan troglodytes verus) in the Nimba Mountains, Guinea

Chimpanzees live in fission-fusion social organizations, which means that party size, composition, and spatial distribution are constantly in flux. Moreover, chimpanzees use a remarkably extensive repertoire of vocal and nonvocal forms of communication, thought to help convey information in such a socially and spatially dynamic setting. One proposed form of nonvocal communication in chimpanzees is buttress drumming, in which an individual hits a tree buttress with its hands and/or feet, thereby producing a low-frequency acoustic signal. It is often presumed that this behavior functions to communicate over long distances and is, therefore, goal-oriented. If so, we would expect chimpanzees to exhibit selectivity in the choice of trees and buttresses used in buttress drumming. Selectivity is a key attribute of many other goal-directed chimpanzee behaviors, such as nut-cracking and ant dipping. Here, we investigate whether chimpanzees at the Seringbara study site in the Nimba Mountains, Guinea, West Africa, show selectivity in their buttress drumming behavior. Our results indicate that Seringbara chimpanzees are more likely to use larger trees and select buttresses that are thinner and have a greater surface area. These findings imply that tree buttress drumming is not a random act, but rather goal-oriented and requires knowledge of suitable trees and buttresses. Our results also point to long-distance communication as a probable function of buttress drumming based on selectivity for buttress characteristics likely to impact sound propagation. This study provides a foundation for further assessing the cognitive underpinnings and functions of buttress drumming in wild chimpanzees

Monkey see, monkey feel? Marmoset reactions towards conspecifics' arousal

Consolation has been observed in several species, including marmoset monkeys, but it is often unclear to what extent they are empathy-based. Marmosets perform well in at least two of three components of empathy-based consolation, namely understanding others and prosociality, but it is unknown to what extent they show matching with others. We, therefore, tested whether non-aroused individuals would become aroused themselves when encountering an aroused group member (indicated by piloerection of the tail). We found a robust contagion effect: group members were more likely to show piloerection themselves after having encountered an aroused versus relaxed conspecific. Moreover, group members offered consolation behaviours (affiliative approaches) towards the aroused fellow group members rather than the latter requesting it. Importantly, this pattern was shown by both aroused and non-aroused individuals, which suggests that they did not do this to reduce their own arousal but rather to console the individual in distress. We conclude that marmosets have all three components of empathy-based consolation. These results are in line with observations in another cooperative breeder, the prairie vole