0000000000053030
AUTHOR
Jonathan M. Jeschke
showing 4 related works from this author
How partnerships end in guillemots Uria aalge : chance events, adaptive change, or forced divorce?
2007
Divorce in socially monogamous species can result from different mechanisms, for example, chance events, active desertion of the partner, or the intrusion of a third individual ousting the partner. We compared the predictions associated with such mechanisms with data from common guillemots (Uria aalge) breeding on the Isle of May, Scotland. The data cover the years 1982--2005 and show a yearly divorce rate of 10.2%. In most divorces (86%), one of the original partners moved to another breeding site, whereas the other bird stayed and bred with a new partner. On average, movers had a significantly lower breeding success after divorce, stayers were largely unaffected, whereas the incoming bird…
Predicting and testing functional responses: An example from a tardigrade–nematode system
2008
Abstract Numerous studies have empirically measured consumer functional responses or theoretically developed response models, but whether these models can quantitatively predict observed data has hardly been tested. We perform such a test for the terrestrial predator–prey system Macrobiotus richtersi (Tardigrada)– Acrobeloides nanus (Nematoda). For two different size classes of A. nanus , we report a functional response as measured in the laboratory and quantitatively compare it to predictions of three models with different degrees of complexity: (1) the disc equation which does not include satiation effects; (2) the steady-state satiation (SSS) equation which assumes a constant level of pr…
Understanding the long-term effects of species invasions
2006
We describe here the ecological and evolutionary processes that modulate the effects of invasive species over time, and argue that such processes are so widespread and important that ecologists should adopt a long-term perspective on the effects of invasive species. These processes (including evolution, shifts in species composition, accumulation of materials and interactions with abiotic variables) can increase, decrease, or qualitatively change the impacts of an invader through time. However, most studies of the effects of invasive species have been brief and lack a temporal context; 40% of recent studies did not even state the amount of time that had passed since the invasion. Ecologists…
Time and energy constraints: reply to Nolet and Klaassen (2005)
2006
Jonathan M. Jeschke, (jonathan.jeschke@gmx.net), Laboratory of Ecological and Evolutionary Dynamics, Dept of Biological and Environmental Sciences, Univ. of Helsinki, P.O. Box 65, FI-00014 Helsinki, Finland; and Evolutionary Ecology Unit, Dept of Biological and Environmental Science, Univ. of Jyvaskyla, P.O. Box 35, FI-40014 Jyvaskyla, Finland. Michael Kopp, Dept Biologie II, Univ. of Munich, Grosshaderner Str. 2, DE-82152 Planegg-Martinsried, Germany. Ralph Tollrian, Biological Sciences, Ruhr-Universitat Bochum, Universitatsstr. 150, DE-44780 Bochum, Germany.