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A dogma in ecology and evolution holds that the environment is an extrinsic force that is not, in turn, shaped by the adaptive evolution of species. Recent work on stickleback life history, community ecology and speciation challenges this dogma., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Forecasts of ecological dynamics in changing environments are increasingly important, and are available for a plethora of variables, such as species abundance and distribution, community structure and ecosystem processes. There is, however, a general absence of knowledge about how far into the future, or other dimensions (space, temperature, phylogenetic distance), useful ecological forecasts can be made, and about how features of ecological systems relate to these distances. The ecological forecast horizon is the dimensional distance for which useful forecasts can be made. Five case studies illustrate the influence of various sources of uncertainty (e.g. parameter uncertainty, environmental variation, demographic stochasticity and evolution), level of ecological organisation (e.g. population or community), and organismal properties (e.g. body size or number of trophic links) on temporal, spatial and phylogenetic forecast horizons. Insights from these case studies demonstrate that the ecological forecast horizon is a flexible and powerful tool for researching and communicating ecological predictability. It also has potential for motivating and guiding agenda setting for ecological forecasting research and development., (© 2015 The Authors Ecology Letters published by John Wiley & Sons Ltd and CNRS.)

1. Helpers that invest energy in provisioning the offspring of related individuals stand to gain indirect fitness benefits from doing so. First, if the helper’s effort is additional to that of the parents (additive) the productivity of the current breeding attempt can be increased. Secondly, if the parents reduce their workload (compensation) this can result in future indirect fitness gains to the helper via increased breeder survival; termed ‘load-lightening’. 2. Long-tailed tits ( Aegithalos caudatus) have a cooperative breeding system in which helpers assist kin and parents exhibit both additive and compensatory reactions in the presence of helpers. Offspring from helped nests are heavier and more likely to recruit into the breeding population, thus helpers gain indirect fitness benefits from increasing the productivity of the current breeding attempt. Despite breeders’ reduction of feeding effort in the presence of helpers, previous investigations found no subsequent increase in breeder survival. 3. The aim of this study was to test the hypothesis that load-lightening resulted in indirect fitness benefits for helpers. We used data from a 14-year study to investigate the provisioning rate, survival and future fecundity of male and female long-tailed tits that did and did not receive help at the nest. 4. We found an asymmetrical response to the presence of helpers at large brood sizes. Males reduced their feeding rate more than females, and this differential response was reflected in a significant increase in male survival when provisioning large broods assisted by helpers. We found no evidence of any increase in future fecundity for helped breeders. 5. The finding that males reduce their provisioning rate in the presence of helpers (at large brood sizes) to a greater degree than females, and that this is reflected in an increase in survival rate for males only, implies that the survival increase is caused by the reduction in work-rate rather than a non-specific benefit of a larger group size. 6. The marginal benefits of help for breeder survival are likely to be more difficult to identify than the increased productivity at helped nests, but should not be overlooked when investigating the potential indirect fitness gains that supernumeraries can accrue by helping. [ABSTRACT FROM AUTHOR]

The article provides information on the issue regarding the parasites cited on the nature's food web system. It mentions the relevance of food web in maintaining and keeping the ecosystem in check and cites the continuous relationship between producers and consumers and between predators and prey. Meanwhile, there are some food web researches have included parasites and pathogenic creatures and notes their contributions to the food web system. Moreover, the significance of these pathogenic parasites for the maintenance and balance of ecology is also discussed.

Predator-generated variation in prey energy intake remains the dominant explanation of adaptive response to predation risk in prey life history, morphology and physiology across a wide range of taxa. This “behavioural hypothesis” suggest that chemical or visual signals of predation risk reduce prey energy intake leading to a life history characterized by a small size and late age at maturity. However, size-selective predation can induce either smaller size–early age or large size–late age life history. The alternative “physiological hypothesis” suggests that size-selective cues decouple the relationship between energy and life history, acting instead directly on development. Here we use a series of experiments in a fish–daphnid predator–prey system to ask whether size-selective predator cues induce a physiological mediation of development, overshadowing behaviourally based changes in food intake. We found fish chemical cues reduce the net energy intake in Daphnia magna, suggesting a behaviourally mediated reduction in energy. Experimental manipulation of food levels show further that reductions in food lead to later but smaller size at maturity. However, in line with the physiological hypothesis, we show that D. magna matures earlier and at a smaller size when exposed to fish predation cues. Furthermore, our data shows that they do this by increasing their development rate (earlier maturity) for a given growth rate, resulting in a smaller size at maturity. Our data, from a classic size-selective predation system, indicate that predator-induced changes in this system are driven by physiological mediation of development rather than behavioural mediation of energy intake. [ABSTRACT FROM AUTHOR]

A major question at the interface of community and behavioural ecology is whether optimal foraging influences patterns of population dynamics. One productive route towards addressing this question has been to treat the solution to an optimal foraging model as an “adaptive” functional response, capable of varying with resource density. Here I integrate resource density into an optimal foraging model by allowing consumption rates, part of the time constraint in the foraging model, to vary in a linear or saturating manner with resource density. Using field estimates to parameterize the model for 11 herbivore mammals and four herbivore Orthoptera, the modeling effort produces a novel set of functional responses that display unique combinations of traditional functional response shapes. These new adaptive functional response shapes arise because of the assumptions about physiology, resource quality and environmental conditions that are embedded in a foraging model. The results of the study indicate that there is 1) resource and body size specific changes in resource intake as resource density varies; 2) a sensitivity of intake to the shape and magnitude of the cropping rate variation; and 3) that herbivores may regulate their resources via the functional response. [ABSTRACT FROM AUTHOR]

Investigates the competition among two species of grasshopper, Melanopus femurrubrum and Chorthippus curtipennis, along a resource gradient. Preference for grass by M. femurrubrum; Negative correlation between the abundance of M. femurrubrum and the abundance of its competitor; Included-niche competition among the two species.

Understanding the genetics of how organisms adapt to changing environments is a fundamental topic in modern evolutionary ecology. The field is currently progressing rapidly because of advances in genomics technologies, especially DNA sequencing. The aim of this review is to first briefly summarise how next generation sequencing (NGS) has transformed our ability to identify the genes underpinning adaptation. We then demonstrate how the application of these genomic tools to ecological model species means that we can start addressing some of the questions that have puzzled ecological geneticists for decades such as: How many genes are involved in adaptation? What types of genetic variation are responsible for adaptation? Does adaptation utilise pre-existing genetic variation or does it require new mutations to arise following an environmental change? [Copyright &y& Elsevier]