Invasion rate of deer ked depends on spatiotemporal variation in host density

Invasive parasites are of great global concern. Understanding the factors influencing the spread of invading pest species is a first step in developing effective countermeasures. Growing empirical evidence suggests that spread rates are essentially influenced by spatiotemporal dynamics of host-parasite interactions, yet approaches modelling spread rate have typically assumed static environmental conditions. We analysed invasion history of the deer ked (Lipoptena cervi) in Finland with a diffusion-reaction model, which assumed either the movement rate, the population growth rate, or both rates may depend on spatial and temporal distribution of moose (Alces alces), the main host of deer ked. We fitted the model to the data in a Bayesian framework, and used the Bayesian information criterion to show that accounting for the variation in local moose density improved the model's ability to describe the pattern of the invasion. The highest ranked model predicted higher movement rate and growth rate of deer ked with increasing moose density. Our results suggest that the historic increase in host density has facilitated the spread of the deer ked. Our approach illustrates how information about the ecology of an invasive species can be extracted from the spatial pattern of spread even with rather limited dat

Applying Interconnected Game Theory to Analyze Transboundary Waters: A Case Study of the Kura-Araks Basin

A number of environmental problems are international in nature, including many water management issues. Rivers, for example, do not recognize political boundaries. Therefore, pollution generated in one country can affect neighboring countries, while water extraction in an upstream country can affect water flow and water availability in a downstream country. The situation creates an interdependency among countries, which might lead to disputes over the management of transboundary water. Therefore, coordination among the countries is necessary for effective management of these transboundary resources. The focus of a recently published study (Khachaturyan and Schoengold, 2018) is the transboundary Kura-Araks Basin (see Figure 1 for its location), which is a major river system in the South Caucasus, with about 11 million people living in the basin. The countries in the basin are Armenia, Azerbaijan, Georgia, Iran, and Turkey, with Armenia, Azerbaijan, and Georgia having over 80 percent of the streamflow. The Kura-Araks Basin is a primary source of water for agricultural, industrial, and municipal uses in the South Caucasian countries. The study determines whether there are economic benefits to be gained from cooperation in the management of the Kura River (shared between Azerbaijan and Georgia), and under what conditions cooperation is an achievable outcome. Azerbaijan withdraws about 35 percent of the total available renewable water resources while Georgia only withdraws about 3 percent

Phytoplankton pigments and dissolved organic matter distribution in the Gulf of Riga

http://www.elsevier.com/locate/issn/09247963The results of field studies of phytoplankton and dissolved organic matter DOM.in the Gulf of Riga in August-September 1993, June 1994 and April 1995 are presented. Actively excited fluorescence in UV- and visible spectral regions was used to investigate spatial distributions of DOM, Chl a, carotenoids and phycoerythrin in surface water. The fluorescent data were collected by means of laser remote sensing spectrometer LIDAR., spectrofluorometers in underway flow-through mode and in the measurements of the water samples. Pronounced variable spatial structures of phytoplankton were observed in spring 1995 and late summer 1993, while in early summer 1994 the pigment distribution was rather homogeneous. The spatial modulation of high-resolution profiles of phytoplankton with the period 3.5-5 km was detected across the gulf in all seasons probably caused by variability of hydrophysical conditions. A negative correlation of DOM concentration in surface waters and salinity was revealed in August-September 1993 and June 1994

Negative density-distribution relationship in butterflies

Peer reviewe

Quantitative trait evolution and environmental change

Peer reviewe

Long-term phonological learning begins at the level of word form

Incidental learning of phonological structures through repeated exposure is an important component of native and foreign-language vocabulary acquisition that is not well understood at the neurophysiological level. It is also not settled when this type of learning occurs at the level of word forms as opposed to phoneme sequences. Here, participants listened to and repeated back foreign phonological forms (Korean words) and new native-language word forms (Finnish pseudowords) on two days. Recognition performance was improved, repetition latency became shorter and repetition accuracy increased when phonological forms were encountered multiple times. Cortical magnetoencephalography responses occurred bilaterally but the experimental effects only in the left hemisphere. Superior temporal activity at 300–600 ms, probably reflecting acoustic-phonetic processing, lasted longer for foreign phonology than for native phonology. Formation of longer-term auditory-motor representations was evidenced by a decrease of a spatiotemporally separate left temporal response and correlated increase of left frontal activity at 600–1200 ms on both days. The results point to item-level learning of novel whole-word representations

Evolution of predator dispersal in relation to spatio-temporal prey dynamics : how not to get stuck in the wrong place!

Peer reviewedPublisher PD

Modeling complex ecological economic systems: toward an evolutionary, dynamic understanding of people and nature

Recent understanding about system dynamics and predictability that has emerged from the study of complex systems is creating new tools for modeling interactions between anthropogenic and natural systems. A range of techniques has become available through advances in computer speed and accessibility and by implementing a broad, interdisciplinary systems view

Copernicus Ocean State Report, issue 6

The 6th issue of the Copernicus OSR incorporates a large range of topics for the blue, white and green ocean for all European regional seas, and the global ocean over 1993–2020 with a special focus on 2020

The effect of dietary restriction on reproduction: a meta-analytic perspective

Background: Dietary restriction (DR), a reduction in the amount of food or particular nutrients eaten, is the most consistent environmental manipulation to extend lifespan and protect against age related diseases. Current evolutionary theory explains this effect as a shift in the resolution of the trade-off between lifespan and reproduction. However, recent studies have questioned the role of reproduction in mediating the effect of DR on longevity and no study has quantitatively investigated the effect of DR on reproduction across species. Results: Here we report a comprehensive comparative meta-analysis of the effect of DR on reproduction. In general, DR reduced reproduction across taxa, but several factors moderated this effect. The effect of DR on reproduction was greater in well-studied model species (yeast, nematode worms, fruit flies and rodents) than non-model species. This mirrors recent results for longevity and, for reproduction, seems to result from a faster rate of decline with decreasing resources in model species. Our results also suggested that not all reproductive traits are affected equally by DR. High and moderate cost reproductive traits suffered a significant reduction with DR, but low cost traits, such as ejaculate production, did not. Although the effect of DR on reproduction was stronger in females than males, this sex difference reduced to near zero when accounting for other co-factors such as the costliness of the reproductive trait. Thus, sex differences in the effect of DR on longevity may be due to a failure to expose males to as complete a range of the costs of reproduction as females. Conclusions: We suggest that to better understand the generality of the effect of DR, future studies should attempt to address the cause of the apparent model species bias and ensure that individuals are exposed to as many of the costs of reproduction as possible. Furthermore, our meta-analytic approach reveals a general shortage of DR studies that record reproduction, particularly in males, as well as a lack of direct side-by-side comparisons of the effect of DR on males and females