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11.
Mate choice and fitness in a hybrid frog: Rana esculenta females prefer Rana lessonae males over their own 总被引:2,自引:0,他引:2
Summary The evolution and maintenance of female choice based on purely genetic differences is still a controversial issue, not only for theoretical reasons, but also because of the practical difficulty of demonstrating the fitness consequences of preferences and heritability of and genetic variability in the chosen traits. We argue that hybrid systems (broadly defined) offer suitable models for studying mate choice according to genetic differences. We present such a study for European water-frogs of the hybridogenetic Rana lessonae/Rana esculenta complex (L/E complex). R. esculenta, originally a hybrid between R. lessonae and R. ridibunda, eliminates the L genome premeiotically and only produces eggs and sperm containing only the R. ridibunda (R) genome. Consequently, the hybrid will only persist when it lives and mates with R. lessonae in mixed populations where it can regain the lost L genome. In such mixed populations, there is strong selection against E x E matings. because these will produce no viable offspring. We tested whether females of the hybrid R. esculenta do indeed avoid their own R. exculenta males and choose males of the parental species R. lessonae instead. Eleven E females were offered a simultaenous choice between one L and one E male. Females exhibited a significant preference for L males that was determined by the type of male, rather than by its size or activity. This choice is in the direction predicted from genetics. The question of why L males agree to mate with E females, but L females only rarely mate with E males, is answered by a sexual asymmetry in the cost/benefit ratios of mating with the wrong type and the right size. Our results are consistent with the mating pattern found in natural populations, but further studies are needed to show that female choice really causes this pattern.Correspondence to: H.-U. Reyer 相似文献
12.
Christopher Reyer Johann Bachinger Ralf Bloch Fred F. Hattermann Pierre L. Ibisch Stefan Kreft Petra Lasch Wolfgang Lucht Christoph Nowicki Peter Spathelf Manfred Stock Martin Welp 《Regional Environmental Change》2012,12(3):523-542
Located in a relatively dry region and characterized by mainly sandy soils, the German Federal State of Brandenburg (surrounding the capital city of Berlin) is especially vulnerable to climate change impacts (e.g., summer droughts) and cascading effects on ecological systems (e.g., decreasing ground water tables, water stress, fire risk, productivity losses) with socioeconomic implications. Furthermore, a complex interplay of unemployment, rural exodus, and an aging population challenges this structurally weak region. We discuss adaptation measures that are either implemented or planned, as well as research into adaptation strategies to climate change for the sectors forestry, agriculture, and water management as well as in nature conservation in light of socioeconomic and ecological challenges and benefits. In doing so, we adopt a systemic view of Brandenburg where the sectors discussed are seen as subsystems embedded in a larger regional system. This at least partially holarchical approach enables the identification of conflicts between adaptation measures, but also of synergies among the sectors that pertain to successful adaptation to climate change. The insights gained ultimately highlight the need for cross-sectoral, adaptive management practices that jointly target a sustainable regional development. 相似文献
13.
Reyer Christopher P.O Otto Ilona M. Adams Sophie Albrecht Torsten Baarsch Florent Cartsburg Matti Coumou Dim Eden Alexander Ludi Eva Marcus Rachel Mengel Matthias Mosello Beatrice Robinson Alexander Schleussner Carl-Friedrich Serdeczny Olivia Stagl Judith 《Regional Environmental Change》2017,17(6):1639-1650
Regional Environmental Change - This paper synthesizes what is known about the physical and biophysical impacts of climate change and their consequences for societies and development under... 相似文献
14.
Otto Ilona M. Reckien Diana Reyer Christopher P. O. Marcus Rachel Le Masson Virginie Jones Lindsey Norton Andrew Serdeczny Olivia 《Regional Environmental Change》2017,17(6):1651-1662
Regional Environmental Change - This article provides a review of recent scientific literature on social vulnerability to climate change, aiming to determine which social and demographic groups,... 相似文献
15.
Resource windfalls,investment, and long-term income 总被引:1,自引:0,他引:1
We develop a simple mechanism to explain why resource windfalls are likely to lower income levels in the long run. Most mineral-producing countries, in particular, fail to maintain incentives for savings and investment after positive resource shocks. Our analysis focuses on this savings–investment transmission channel through which resource rents affect welfare, and develops an OverLapping-Generations (OLG) model with features from endogenous growth theory to study the mechanism. In this model, savings adjust downwards to income from natural resources, investments adjust to savings, and subsequently the level of overall productivity falls. Resource affluence has two counteracting effects on income. In the short term, resource wealth augments income, but in the long-term, it decreases income through a crowding-out effect on knowledge creation. 相似文献
16.
Alternative forest management strategies to account for climate change-induced productivity and species suitability changes in Europe 总被引:1,自引:0,他引:1
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Reyer Christopher P. O. Rigaud Kanta Kumari Fernandes Erick Hare William Serdeczny Olivia Schellnhuber Hans Joachim 《Regional Environmental Change》2017,17(6):1563-1568
Regional Environmental Change - 相似文献
19.
Sex-specific nest defense in house sparrows (Passer domesticus) varies with badge size of males 总被引:2,自引:0,他引:2
Heinz-Ulrich Reyer Wiltrud Fischer Pascale Steck Thomas Nabulon Philip Kessler 《Behavioral ecology and sociobiology》1998,42(2):93-99
According to indicator models of sexual selection, females can benefit from choosing males with above average epigamic traits,
but empirical evidence for such benefits is scarce. Here, we report results from an experiment with 29 pairs of house sparrows
(Passer domesticus) where the intensity of nest defense against a mounted mustelid predator was related to the size of the black throat and
breast patch (“badge”) in males. Using principal components analysis (PCA), original response variables of both sexes were
reduced to two factors: “Approach” to the predator and “Distant warning”. “Approach”, the more risky behavior, increased from
small- through medium- to large-badged males and decreased in their females. Since large-badged males have a higher certainty
of paternity (i.e. greater benefits from defense) and may be older and more experienced (i.e. incur lower costs), the most
likely explanation for male defense intensity increasing with badge size is an improving benefit/cost ratio. The resulting
optimal response of their females and evolutionarily stable participation in joint parental care is illustrated by a graphical
model. It shows that females would, indeed, benefit directly from choosing large-badged males. This, however, is no proof
of a direct evolutionary tie between badge size and paternal behavior, as assumed by indicator models of sexual selection.
It may simply represent a spurious relationship, originating from the correlation of badge size and defense with confidence
of paternity.
Received: 22 September 1997 / Accepted after revision: 3 November 1997 相似文献