Nematode gastrulation: having a BLASTocoel!

During gastrulation of the nematode worm Caenorhabditis elegans, individual cells ingress into a solid ball of cells. Gastrulation in a basal nematode, in contrast, has now been found to occur by invagination into a blastocoel, revealing an unanticipated embryological affinity between nematodes and all other triploblastic metazoans.     

Endangered species and a threatened discipline: behavioural ecology

Behavioural ecologists often see little connection between the current conservation crisis and the future of their discipline. This view is myopic because our abilities to investigate and interpret the adaptive significance and evolutionary histories of behaviours are increasingly being compromised in human-dominated landscapes because of species extinctions, habitat destruction, invasive species, pollution, and climate change. In this review, we argue that many central issues in behavioural ecology will soon become prohibitively difficult to investigate and interpret, thus impeding the rapid progress that characterizes the field. To address these challenges, behavioural ecologists should design studies not only to answer basic scientific questions but also to provide ancillary information for protection and management of their study organisms and habitats, and then share their biological insights with the applied conservation community.     

Biotelemetry: a mechanistic approach to ecology

Remote measurement of the physiology, behaviour and energetic status of free-living animals is made possible by a variety of techniques that we refer to collectively as 'biotelemetry'. This set of tools ranges from transmitters that send their signals to receivers up to a few kilometers away to those that send data to orbiting satellites and, more frequently, to devices that log data. They enable researchers to document, for long uninterrupted periods, how undisturbed organisms interact with each other and their environment in real time. In spite of advances enabling the monitoring of many physiological and behavioural variables across a range of taxa of various sizes, these devices have yet to be embraced widely by the ecological community. Our review suggests that this technology has immense potential for research in basic and applied animal ecology. Efforts to incorporate biotelemetry into broader ecological research programs should yield novel information that has been challenging to collect historically from free-ranging animals in their natural environments. Examples of research that would benefit from biotelemetry include the assessment of animal responses to different anthropogenic perturbations and the development of life-time energy budgets.     

Laboratory-dependent bacterial ecology: a cautionary tale

Although laboratory dependence is an acknowledged problem in microbiology, it is seldom intensively studied or discussed. We demonstrate that laboratory dependence is real and quantifiable even in the popular model Escherichia coli. Here laboratory effects alter the equilibrium composition of a simple community composed of two strains of E. coli. Our data rule out changes in the bacterial strains, chemical batches, and human handling but implicate differences in growth medium, especially the water component.     

Research on fish ecology in Japan: a brief history and selected review

Fish play an important role in the culture of Japan, supplying the primary source of food protein. Research on fish ecology in Japan began developing about 1955, and paralleled that in North America and Europe, but has a number of unique differences. Two main research foci, stream fish ecology and ecology of Lake Biwa, were founded by H. Kawanabe and his colleagues while graduate students in D. Miyadi's laboratory at Kyoto University in the 1950s. The focus on studies of individual differences in ecology, life history, and behavior by direct observation that were developed in this laboratory had a pervasive influence on research that has continued to the present. In the 1980s, Kawanabe, who had succeeded Miyadi as laboratory head, also co-organized a major research project on the complex communities of cichlid fishes in Lake Tanganyika, which has involved nearly every major Japanese investigator in fish ecology since. A review of research conducted by Japanese investigators in stream fish ecology, ecology of fishes in lakes Biwa and Tanganyika, and marine reef fish ecology revealed a wealth of literature of which most English-speaking fish ecologists are unaware. The most striking difference between Western and Japanese research is the focus on detailed observations and experiments in natural habitats of individual differences in behavior, life history, and ecology, and how these ultimately affect processes at the population and community level, as amply demonstrated by Kawanabe's early work on ayu, Plecoglossus altivelis. This approach predated by 20–30 years the current interest in individual differences and individual-based models in North America and Europe.     

Levels of understanding in ecology: interspecific competition and community ecology

Abstract Ecological interpretation has been subject to several divisive controversies, involving, for example, the significance of density dependence and interspecific competition as ecological processes. Generally, resolution has been obtained through compromise and concensus or calls for yet more data. Essentially, both sides in the discussion are seen to have been correct to some extent. As a consequence the debates have been portrayed widely as having been sterile. We agree, but only because they have been conducted at a level so superficial that the relevance of the original criticisms to the theoretical structure of ecology has not been widely appreciated, nor resolved. Debate that deals with ecological generalizations must be conducted at a level appropriate to such aims.     

Ecoinformatics: supporting ecology as a data-intensive science

Ecology is evolving rapidly and increasingly changing into a more open, accountable, interdisciplinary, collaborative and data-intensive science. Discovering, integrating and analyzing massive amounts of heterogeneous data are central to ecology as researchers address complex questions at scales from the gene to the biosphere. Ecoinformatics offers tools and approaches for managing ecological data and transforming the data into information and knowledge. Here, we review the state-of-the-art and recent advances in ecoinformatics that can benefit ecologists and environmental scientists as they tackle increasingly challenging questions that require voluminous amounts of data across disciplines and scales of space and time. We also highlight the challenges and opportunities that remain.     

Time for a change: dynamic urban ecology

Contemporary cities are expanding rapidly in a spatially complex, non-linear manner. However, this form of expansion is rarely taken into account in the way that urbanization is classically assessed in ecological studies. An explicit consideration of the temporal dynamics, although frequently missing, is crucial in order to understand the effects of urbanization on biodiversity and ecosystem functioning in rapidly urbanizing landscapes. In particular, a temporal perspective highlights the importance of land-use legacies and transient dynamics in the response of biodiversity to environmental change. Here, we outline the essential elements of an emerging framework for urban ecology that incorporates the characteristics of contemporary urbanization and thus empowers ecologists to understand and intervene in the planning and management of cities.     

Diadromy,history and ecology: a question of scale

The existence of diadromous migrations has significant implications for understanding a broad series of biogeographical and ecological questions and for doing so across a broad range of spatial and temporal scales. Understanding these implications is important for interpretation of patterns in historical and ecological biogeography as well as in community ecology and conservation. This article explores these implications. Guest editors: S. Dufour, E. Prévost, E. Rochard & P. Williot Fish and diadromy in Europe (ecology, management, conservation)     

Linking behavioural syndromes and cognition: a behavioural ecology perspective

With the exception of a few model species, individual differences in cognition remain relatively unstudied in non-human animals. One intriguing possibility is that variation in cognition is functionally related to variation in personality. Here, we review some examples and present hypotheses on relationships between personality (or behavioural syndromes) and individual differences in cognitive style. Our hypotheses are based largely on a connection between fast-slow behavioural types (BTs; e.g. boldness, aggressiveness, exploration tendency) and cognitive speed-accuracy trade-offs. We also discuss connections between BTs, cognition and ecologically important aspects of decision-making, including sampling, impulsivity, risk sensitivity and choosiness. Finally, we introduce the notion of cognition syndromes, and apply ideas from theories on adaptive behavioural syndromes to generate predictions on cognition syndromes.     

Tangled nature: a model of evolutionary ecology

We discuss a simple model of co-evolution. In order to emphasize the effect of interaction between individuals, the entire population is subjected to the same physical environment. Species are emergent structures and extinction, origination and diversity are entirely a consequence of co-evolutionary interaction between individuals. For comparison, we consider both asexual and sexually reproducing populations. In either case, the system evolves through periods of hectic reorganization separated by periods of coherent stable coexistence.     

Species' borders: a unifying theme in ecology

Biologists have long been fascinated by species' borders, and with good reason. Understanding the ecological and evolutionary dynamics of species' borders may prove to be the key that unlocks new understanding across a wide range of biological phenomena. After all, geographic range limits are a point of entry into understanding the ecological niche and threshold responses to environmental change. Elucidating patterns of gene flow to, and returning from, peripheral populations can provide important insights into the nature of adaptation, speciation and coevolution. Species' borders form natural laboratories for the study of the spatial structure of species interactions. Comparative studies from the center to the margin of species' ranges allow us to explore species' demographic responses along gradients of increasing environmental stress. Range dynamics further permit investigation into invasion dynamics and represent bellwethers for a changing climate. This set of papers explores ecological and evolutionary dynamics of species' borders from diverse empirical and theoretical perspectives.     

Population ecology on an environmental gradient: Cakile edentula on a sand dune

Summary A naturally-occurring sand dune population of the annual plant Cakile edentula (Brassicaceae) was studied for two years. The plants grew along an environmental gradient stretching from open sand beach (seaward) to densely vegetated dunes (landward). Survivorship and reproductive output were estimated from plants in permanent quadrats. The dispersal of seeds was documented by sifting fruits from the sand substrate at different seasons.Seedlings germinate in April and May and begin flowering in July and August. They may continue to flower until October unless destroyed by autumn winds or heavy frost. Although seaward plants germinate approximately a month later than landward plants, they grow more rapidly and by September may be two orders of magnitude larger than landward plants (dry weight of vegetative parts 6.86±3.97 g compared to 0.029±0.006 g; dry weight of fruits 5.92±4.27 g compared to 0.016±0.005 g; mean with 95% CI). In both years, seedling survivorship and mature plant reproductive output declined significantly with distance landward. The large plants at the seaward end of the gradient produced most of the fruits (144 and 278 fruits per capita in 1975 and 1976 respectively) but a large proportion of these were moved landward by wind and waves during the winter. Thus, at the seaward end of the gradient, the main influx on individuals was from reproduction, and the main loss of individuals was from dispersal landward during the winter. The small plants at the landward end of the gradient produced few fruits (1.8 and 1.2 fruits per capita in 1975 and 1976 respectively), and mortality greatly exceeded this reproductive output. Thus, at the landward end of the gradient, the main loss of individuals was through seedling mortality, but this was balanced by a large annual influx of individuals from the seaward end of the gradient. Plants at the landward end of the gradient therefore exist only because of annual dispersal of seeds landward. Most seeds produced at the seaward end of the gradient disperse from an area of good habitat (high survivorship and high reproductive output) to an area of poor habitat (low survivorship and low reproductive output).     

Host-parasitoid spatial ecology: a plea for a landscape-level synthesis

A growing body of literature points to a large-scale research approach as essential for understanding population and community ecology. Many of our advances regarding the spatial ecology of predators and prey can be attributed to research with insect parasitoids and their hosts. In this review, we focus on the progress that has been made in the study of the movement and population dynamics of hosts and their parasitoids in heterogeneous landscapes, and how this research approach may be beneficial to pest management programs. To date, few studies have quantified prey and predator rates and ranges of dispersal and population dynamics at the patch level--the minimum of information needed to characterize population structure. From host-parasitoid studies with sufficient data, it is clear that the spatial scale of dispersal can differ significantly between a prey and its predators, local prey extinctions can be attributed to predators and predator extinction risk at the patch level often exceeds that of the prey. It is also evident that populations can be organized as a single, highly connected (patchy) population or as semi-independent extinction-prone local populations that collectively form a persistent metapopulation. A prey and its predators can also differ in population structure. At the landscape level, agricultural studies indicate that predator effects on its prey often spill over between the crop and surrounding area (matrix) and can depend strongly on landscape structure (e.g. the proportion of suitable habitat) at scales extending well beyond the crop margins. In light of existing empirical data, predator-prey models are typically spatially unrealistic, lacking important details on boundary responses and movement behaviour within and among patches. The tools exist for conducting empirical and theoretical research at the landscape level and we hope that this review calls attention to fertile areas for future exploration.     

Impact of supply-side ecology on consumer-mediated coexistence: evidence from a meta-analysis

Studies of marine nearshore hard substrates have demonstrated that consumers and abiotic disturbances can remove biomass, clearing space for species that are competitively subordinate and subsequently increasing diversity. However, studies often examine the impact of these space-opening forces on diversity in isolation from other potentially interacting factors. In marine systems, space can be closed by recruitment decoupled from local populations. Therefore, we investigated how recruitment influences the impacts of consumers on diversity with a meta-analysis of 27 experiments of community development involving sessile species on marine hard substrates. These studies allowed quantification of recruitment rates, consumer pressure, and species richness of primary space occupants. This meta-analysis demonstrated that consumers generally increase diversity at high levels of recruitment but decrease diversity at low levels of recruitment. Therefore, species diversity of sessile species is controlled by the interaction between forces that open (predation and herbivory) and close (recruitment) space.