Detecting context dependence in the expression of life history trade-offs.

Life history trade-offs are one of the central tenets of evolutionary demography. Trade-offs, depicting negative covariances between individuals' life history traits, can arise from genetic constraints, or from a finite amount of resources that each individual has to allocate in a zero-sum game between somatic and reproductive functions. While theory predicts that trade-offs are ubiquitous, empirical studies have often failed to detect such negative covariances in wild populations.

Multifaceted density dependence: Social structure and seasonality effects on Serengeti lion demography.

Interactions between density and environmental conditions have important effects on vital rates and consequently on population dynamics and can take complex pathways in species whose demography is strongly influenced by social context, such as the African lion, Panthera leo. In populations of such species, the response of vital rates to density can vary depending on the social structure (e.g.

Comparative life-history responses of lacewings to changes in temperature.

Insects play a crucial role in all ecosystems, and are increasingly exposed to higher in temperature extremes under climate change, which can have substantial effects on their abundances. However, the effects of temperature on changes in abundances or population fitness are filtered through differential responses of life-history components, such as survival, reproduction, and development, to their environment. Such differential responses, or trade-offs, have been widely studied in birds and mammals, but comparative studies on insects are largely lacking, limiting our understanding of key mechanisms that may buffer or exacerbate climate-change effects across insect species.

Population Dynamic Consequences of Context-Dependent Trade-Offs across Life Histories.

AbstractTrade-offs are central to life history theory and play a role in driving life history diversity. They arise from a finite amount of resources that need to be allocated among different functions by an organism. Yet covariation of demographic rates among individuals frequently do not reflect allocation trade-offs because of variation in resource acquisition.

Are some species more sensitive to environmental change than others? It may all depend on the context.

Research Highlight: Rademaker, M., van Leeuwen, A., & Smallegange, I.

Extinction risks and mitigation for a megaherbivore, the giraffe, in a human-influenced landscape under climate change.

Megaherbivores play "outsized" roles in ecosystem functioning but are vulnerable to human impacts such as overhunting, land-use changes, and climate extremes. However, such impacts-and combinations of these impacts-on population dynamics are rarely examined using empirical data. To guide effective conservation actions under increasing global-change pressures, we developed a socially structured individual-based model (IBM) using long-term demographic data from female giraffes (Giraffa camelopardalis) in a human-influenced landscape in northern Tanzania, the Tarangire Ecosystem.

Destabilizing effect of climate change on the persistence of a short-lived primate.

Seasonal tropical environments are among those regions that are the most affected by shifts in temperature and rainfall regimes under climate change, with potentially severe consequences for wildlife population persistence. This persistence is ultimately determined by complex demographic responses to multiple climatic drivers, yet these complexities have been little explored in tropical mammals. We use long-term, individual-based demographic data (1994 to 2020) from a short-lived primate in western Madagascar, the gray mouse lemur (), to investigate the demographic drivers of population persistence under observed shifts in seasonal temperature and rainfall.

Pathways to global-change effects on biodiversity: new opportunities for dynamically forecasting demography and species interactions.

In structured populations, persistence under environmental change may be particularly threatened when abiotic factors simultaneously negatively affect survival and reproduction of several life cycle stages, as opposed to a single stage. Such effects can then be exacerbated when species interactions generate reciprocal feedbacks between the demographic rates of the different species. Despite the importance of such demographic feedbacks, forecasts that account for them are limited as individual-based data on interacting species are perceived to be essential for such mechanistic forecasting-but are rarely available.

Demographic consequences of changes in environmental periodicity.

The fate of natural populations is mediated by complex interactions among vital rates, which can vary within and among years. Although the effects of random, among-year variation in vital rates have been studied extensively, relatively little is known about how periodic, nonrandom variation in vital rates affects populations. This knowledge gap is potentially alarming as global environmental change is projected to alter common periodic variations, such as seasonality.

A sex skew in life-history research: the problem of missing males.

Life-history strategies are diverse. While understanding this diversity is a fundamental aim of evolutionary biology and biodemography, life-history data for some traits-in particular, age-dependent reproductive investment-are biased towards females. While other authors have highlighted this sex skew, the general scale of this bias has not been quantified and its impact on our understanding of evolutionary ecology has not been discussed.

A Trade-Off between Robustness to Environmental Fluctuations and Speed of Evolution.

AbstractUnderstanding how a species' life history affects its capacity to cope with environmental changes is important in the context of rapid climate changes. Reinterpreting previous results from a well-developed theoretical framework, we show that a trade-off exists between a species' ability to genetically adapt to long-term gradual environmental changes and its ability to demographically resist short-term environmental perturbations, causing variation in its vital rates. Surprisingly, this important insight has not been made formally explicit before.

Dispersal Decreases Survival but Increases Reproductive Opportunities for Subordinates in a Cooperative Breeder.

AbstractIn most socially structured populations, the formation of new groups depends on the survival and reproduction of dispersing individuals. Quantifying vital rates in dispersers, however, is difficult because of the logistic challenges of following wide-ranging animals. Here, using data from free-ranging meerkats (), we estimate survival and reproduction of dispersing females and compare these estimates to data for established residents.

Moving towards the ecological intensification of tree plantations.

The growing demand for timber and the boom in massive tree-planting programs could mean the spreading of mismanaged tree plantations worldwide. Here, we apply the concept of ecological intensification to forestry systems as a viable biodiversity-focused strategy that could be critical to develop productive, yet sustainable, tree plantations. Tree plantations can be highly productive if tree species are properly combined to complement their ecological functions.

The myriad of complex demographic responses of terrestrial mammals to climate change and gaps of knowledge: A global analysis.

Approximately 25% of mammals are currently threatened with extinction, a risk that is amplified under climate change. Species persistence under climate change is determined by the combined effects of climatic factors on multiple demographic rates (survival, development and reproduction), and hence, population dynamics. Thus, to quantify which species and regions on Earth are most vulnerable to climate-driven extinction, a global understanding of how different demographic rates respond to climate is urgently needed.

Herbaceous perennial plants with short generation time have stronger responses to climate anomalies than those with longer generation time.

There is an urgent need to synthesize the state of our knowledge on plant responses to climate. The availability of open-access data provide opportunities to examine quantitative generalizations regarding which biomes and species are most responsive to climate drivers. Here, we synthesize time series of structured population models from 162 populations of 62 plants, mostly herbaceous species from temperate biomes, to link plant population growth rates (λ) to precipitation and temperature drivers.

Volatile and Semi-Volatile Organic Compounds May Help Reduce Pollinator-Prey Overlap in the Carnivorous Plant Drosophyllum lusitanicum (Drosophyllaceae).

Most carnivorous plants show a conspicuous separation between flowers and leaf-traps, which has been interpreted as an adaptive response to minimize pollinator-prey conflicts which will reduce fitness. Here, we used the carnivorous subshrub Drosophyllum lusitanicum (Drosophyllaceae) to explore if and how carnivorous plants with minimal physical separation of flower and trap avoid or reduce a likely conflict of pollinator and prey. We carried out an extensive field survey in the Aljibe Mountains, at the European side of the Strait of Gibraltar, of pollinating and prey insects of D.

Assessing seasonal demographic covariation to understand environmental-change impacts on a hibernating mammal.

Natural populations are exposed to seasonal variation in environmental factors that simultaneously affect several demographic rates (survival, development and reproduction). The resulting covariation in these rates determines population dynamics, but accounting for its numerous biotic and abiotic drivers is a significant challenge. Here, we use a factor-analytic approach to capture partially unobserved drivers of seasonal population dynamics.

An ecological perspective on 'plant carnivory beyond bogs': nutritional benefits of prey capture for the Mediterranean carnivorous plant Drosophyllum lusitanicum.

Background And Aims: Little is known about the evolutionary and ecological drivers of carnivory in plants, particularly for those terrestrial species that do not occur in typical swamp or bog habitats. The Mediterranean endemic Drosophyllum lusitanicum (Drosophyllaceae) is one of very few terrestrial carnivorous plant species outside of Australia to occur in seasonally dry, fire-prone habitats, and is thus an ecological rarity. Here we assess the nutritional benefits of prey capture for D.

Life history responses of meerkats to seasonal changes in extreme environments.

Species in extreme habitats increasingly face changes in seasonal climate, but the demographic mechanisms through which these changes affect population persistence remain unknown. We investigated how changes in seasonal rainfall and temperature influence vital rates and viability of an arid environment specialist, the Kalahari meerkat, through effects on body mass. We show that climate change-induced reduction in adult mass in the prebreeding season would decrease fecundity during the breeding season and increase extinction risk, particularly at low population densities.

Removal of pharmaceuticals in urban wastewater: High rate algae pond (HRAP) based technologies as an alternative to activated sludge based processes.

Microalgae biotechnology is a promising tool for many applications, including the elimination of nutrients and other contaminants from wastewater. In this work, we measured the removal efficiency of two wastewater treatment processes: an activated-sludge based conventional process and another based on microalgae biotechnology using high-rate algae ponds (HRAPs). The latter was tested using two different configurations.

Interactive life-history traits predict sensitivity of plants and animals to temporal autocorrelation.

Temporal autocorrelation in demographic processes is an important aspect of population dynamics, but a comprehensive examination of its effects on different life-history strategies is lacking. We use matrix population models from 454 plant and animal populations to simulate stochastic population growth rates (log λ ) under different temporal autocorrelations in demographic rates, using simulated and observed covariation among rates. We then test for differences in sensitivities, or changes of log λ to changes in autocorrelation among two major axes of life-history strategies, obtained from phylogenetically informed principal component analysis: the fast-slow and reproductive-strategy continua.

Defining the role of fire in alleviating seed dormancy in a rare Mediterranean endemic subshrub.

Fire is a topical issue in the management of many ecosystems globally that face a drying climate. Understanding the role of fire in such ecosystems is critical to inform appropriate management practices, particularly in the case of rare and ecologically specialized species. The Mediterranean heathlands are highly fire-prone and occur in a biodiversity hotspot increasingly threatened by human activities, and determining the reproductive thresholds of at-risk heathland species is critical to ensuring the success of future conservation initiatives.

Effects of extreme rainfall events on the distribution of selected emerging contaminants in surface and groundwater: The Guadalete River basin (SW, Spain).

This study is focused on the Guadalete River basin (SW, Spain), where extreme weather conditions have become common, with and alternation between periods of drought and extreme rainfall events. Combined sewer overflows (CSOs) occur when heavy rainfall events exceed the capacity of the wastewater treatment plants (WWTP), as well as pollution episodes in parts of the basin due to uncontrolled sewage spills and the use of reclaimed water and sludge from the local WWTP. The sampling was carried out along two seasons and three campaigns during dry (March 2007) and extreme rainfall (April and December 2010) in the Guadalete River, alluvial aquifer and Jerez de la Frontera aquifer.

Effective prey attraction in the rare Drosophyllum lusitanicum, a flypaper-trap carnivorous plant.

Premise Of The Study: Carnivorous plants have unusually modified leaves to trap insects as an adaptation to low-nutrient environments. Disparate mechanisms have been suggested as luring traits to attract prey insects into their deadly leaves, ranging from very elaborate to none at all. Drosophyllum lusitanicum is a rare carnivorous plant with a common flypaper-trap mechanism.