نتایج جستجو برای: ten predator species

تعداد نتایج: 661804  

Journal: :Biology letters 2011
John N Griffin Brian R Silliman

Despite the global vulnerability of predators to extinction, and the critical functional role they play in many ecosystems, there have been few realistic tests of the consequences of predator species deletion (conversely, predator diversity) in natural ecosystems. We performed a four-month field experiment in a southeastern United States salt marsh to test the role of predatory crab diversity i...

Journal: :Theoretical population biology 2013
Martin Hartvig Ken Haste Andersen

Species with a large adult-offspring size ratio and a preferred predator-prey mass ratio undergo ontogenetic trophic niche shift(s) throughout life. Trophic interactions between such species vary throughout life, resulting in different species-level interaction motifs depending on the maximum adult sizes and population size distributions. We explore the assembly and potential for coexistence of...

Journal: :Journal of nematology 1986
R W Parmelee D G Alston

The effect of tillage intensity on nematode community trophic structure and the role of nematodes in the regulation of decomposition rates in agroecosystems were examined. Conventional (CT) and no-tillage (NT) agroecosystems were sampled monthly for 1 year. Tillage affected nematode trophic structure and total abundance. Monthly mean densities of bacterivorous, fungivorous, and total nematodes ...

بیژن حاتمی, , زینت احمدزاده, ,

Greenhouse whitefly, Trialeurodes vaporariorum West., is one of the most important pests of field crops and ornamental plants in greenhouses which usually controlled by chemical insecticide and/or by biologic control factors. In this study the effect of singular and integrated use of Confidor and predator, Chrysoperla carnea (Steph.) against different nymphal instars of the pest on tomato plant...

2017
Todd C. Atwood Eric Gese Kyran Kunkel TODD C. ATWOOD

Minimizing risk of predation from multiple predators can be difficult, particularly when the risk effects of one predator species may influence vulnerability to a second predator species. We decomposed spatial risk of predation in a 2-predator, 2-prey system into relative risk of encounter and, given an encounter, conditional relative risk of being killed. Then, we generated spatially explicit ...

2013
Claudia Stephan Thomas Bugnyar

Advanced inferring abilities that are used for predator recognition and avoidance have been documented in a variety of animal species that produce alarm calls. In contrast, evidence for cognitive abilities that underpin predation avoidance in nonalarm-calling species is restricted to associative learning of heterospecific alarm calls and predator presence. We investigated cognitive capacities t...

Journal: :Proceedings. Biological sciences 2015
Genevieve M Kozak Janette W Boughman

Predation risk can alter female mating decisions because the costs of mate searching and selecting attractive mates increase when predators are present. In response to predators, females have been found to plastically adjust mate preference within species, but little is known about how predators alter sexual isolation and hybridization among species. We tested the effects of predator exposure o...

2017
Richard Zhang Patricia M. Gray

In evolutionary biology, predator-prey species pairs can be observed participating in evolutionary arms races between adaptations and counter-adaptations. For example, as a prey becomes more adept at avoiding capture, its predator becomes a more adept hunter. The rough-skinned newt (Taricha granulosa) produces a toxin that protects it from virtually all predators, except one. That one predator ...

2007
Weibing Wang Jianhua Shen Juan J. Nieto

In biomathematics, many mathematical models have been established to describe the relationships between species and the outer environment, and the connections between different species. Among the relationships between the species living in the same outer environment, the predator-prey theory plays an important and fundamental role. The dynamic relationship between predators and their prey has l...

2015
Gail S. Robertson Mark Bolton Paul Morrison Pat Monaghan Yan Ropert-Coudert

Ecologically similar sympatric species, subject to typical environmental conditions, may be expected to exhibit synchronous temporal fluctuations in demographic parameters, while populations of dissimilar species might be expected to show less synchrony. Previous studies have tested for synchrony in different populations of single species, and those including data from more than one species hav...

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