Competition between harvester ants and rodents in the cold desert
... Vbstract.— Local distribution patterns of three rodent species {Perognathus parvus, Perormjscus manictihitus, Rcithwdontomys megalotis) were studied in areas of high and low densities of harvester ants (Pogommiyrmex outjhcci) in Raft River Valley, Idaho. Numbers of rodents were greatest in areas of ...
... Vbstract.— Local distribution patterns of three rodent species {Perognathus parvus, Perormjscus manictihitus, Rcithwdontomys megalotis) were studied in areas of high and low densities of harvester ants (Pogommiyrmex outjhcci) in Raft River Valley, Idaho. Numbers of rodents were greatest in areas of ...
Will Small Population Sizes Warn Us of Impending Extinctions?
... extinction at t p 80, when N ∗ p 0. However, the increasing death rate initiates consumer-resource cycles in what had been a stable system. The cycles hide the underlying negative trend in N ∗ until close to t p 60, when the death rate has already grown by approximately 75% of the increase required ...
... extinction at t p 80, when N ∗ p 0. However, the increasing death rate initiates consumer-resource cycles in what had been a stable system. The cycles hide the underlying negative trend in N ∗ until close to t p 60, when the death rate has already grown by approximately 75% of the increase required ...
Scale-dependent interactions and community
... suggesting that either biotic (competition) or abiotic factors (recruitment failure, for instance because of increased inundation) limits forb establishment or survival within the Spartina zone. This would imply that facilitation prevails only at a certain distance, whereas other factors determine f ...
... suggesting that either biotic (competition) or abiotic factors (recruitment failure, for instance because of increased inundation) limits forb establishment or survival within the Spartina zone. This would imply that facilitation prevails only at a certain distance, whereas other factors determine f ...
Parasite establishment in host communities - People
... contacts across than within species. In this case, a mixture of host species more readily sustains the parasite than does either host alone. This matches the ÔcomplementaryÕ resource case of Tilman (1982). Two final cases correspond to situations where there is, for one or both host species, no thre ...
... contacts across than within species. In this case, a mixture of host species more readily sustains the parasite than does either host alone. This matches the ÔcomplementaryÕ resource case of Tilman (1982). Two final cases correspond to situations where there is, for one or both host species, no thre ...
Effects of predation risk on group size, vigilance
... Antipredator responses to large carnivores and the costs of response Until very recently, most discussions of predation in the context of ungulate population dynamics focused solely on direct mortality, but if predation risk affects the demography and dynamics of ungulates as it does other species ( ...
... Antipredator responses to large carnivores and the costs of response Until very recently, most discussions of predation in the context of ungulate population dynamics focused solely on direct mortality, but if predation risk affects the demography and dynamics of ungulates as it does other species ( ...
ABS 415 Help Education Expert/abs415helpdotcom
... • Describe the three main types of predator defined in ecology. How does an understanding of fitness, abundance, and foraging behavior help us understand predation? How does environmental patchiness or fragmentation affect predator–prey populations? ...
... • Describe the three main types of predator defined in ecology. How does an understanding of fitness, abundance, and foraging behavior help us understand predation? How does environmental patchiness or fragmentation affect predator–prey populations? ...
Long-term dynamics of three benthic Ampelisca (Crustacea
... probability for a juvenile to pass into the adult stage λ i and a parameter α i which measures the strength of the The ‘pollution factor‘ (PolFact) is a coefficient effects of hydrocarbons on individuals of species i. between 0 and 1 which has the form described by Appendix 1 and Fig. 1b,c illustrat ...
... probability for a juvenile to pass into the adult stage λ i and a parameter α i which measures the strength of the The ‘pollution factor‘ (PolFact) is a coefficient effects of hydrocarbons on individuals of species i. between 0 and 1 which has the form described by Appendix 1 and Fig. 1b,c illustrat ...
experimental ecology of food webs: complex systems in temporary
... The natural history of temporary ponds Each time a pond fills with water, a new episode in community ecology begins as species arrive to take advantage of the opportunity to complete the free-living aquatic stage of their life cycle. A flush of nutrients occurs as run-off water collects in the pond’ ...
... The natural history of temporary ponds Each time a pond fills with water, a new episode in community ecology begins as species arrive to take advantage of the opportunity to complete the free-living aquatic stage of their life cycle. A flush of nutrients occurs as run-off water collects in the pond’ ...
Comparative ecology of desert small mammals: a
... in experimental enclosures and foraging trays to quantify their foraging, researchers have assessed habitat preferences of species both in isolation and in the presence of competitors. Much of their work has focused on Gerbillus andersoni allenbyi and G. pyramidum, both of which favor semistabilized ...
... in experimental enclosures and foraging trays to quantify their foraging, researchers have assessed habitat preferences of species both in isolation and in the presence of competitors. Much of their work has focused on Gerbillus andersoni allenbyi and G. pyramidum, both of which favor semistabilized ...
Interaction strengths in food webs
... 1. Recent efforts to understand how the patterning of interaction strength affects both structure and dynamics in food webs have highlighted several obstacles to productive synthesis. Issues arise with respect to goals and driving questions, methods and approaches, and placing results in the context ...
... 1. Recent efforts to understand how the patterning of interaction strength affects both structure and dynamics in food webs have highlighted several obstacles to productive synthesis. Issues arise with respect to goals and driving questions, methods and approaches, and placing results in the context ...
Interaction strengths in food webs - Centre for Biodiversity Theory
... 1. Recent efforts to understand how the patterning of interaction strength affects both structure and dynamics in food webs have highlighted several obstacles to productive synthesis. Issues arise with respect to goals and driving questions, methods and approaches, and placing results in the context ...
... 1. Recent efforts to understand how the patterning of interaction strength affects both structure and dynamics in food webs have highlighted several obstacles to productive synthesis. Issues arise with respect to goals and driving questions, methods and approaches, and placing results in the context ...
Herbicidal effect of Ailanthus altissima leaves water extracts on
... Although ailanthone may not be the only phytotoxic compound in A. altissima tissues it is the most active as shown by Heisey (1993) who identified it as a component responsible for the phytotoxic effect, and Heisey (1996) who compared the toxicity of pure ailanthone to those of root bark extracts. O ...
... Although ailanthone may not be the only phytotoxic compound in A. altissima tissues it is the most active as shown by Heisey (1993) who identified it as a component responsible for the phytotoxic effect, and Heisey (1996) who compared the toxicity of pure ailanthone to those of root bark extracts. O ...
GROWTH AND PRODUCTION OF THE BARNACLE BALANUS
... 1961) were not observed at Quequen because recruitment rate was low and thus individuals were commonly isolated on the substratum. The influence of sewage pollution on the growth rate of B. amphitrite cannot be assessed in the field, since this species is absent in nonpolluted intertidal areas. Mort ...
... 1961) were not observed at Quequen because recruitment rate was low and thus individuals were commonly isolated on the substratum. The influence of sewage pollution on the growth rate of B. amphitrite cannot be assessed in the field, since this species is absent in nonpolluted intertidal areas. Mort ...
Supporting Materials
... realizations of a hypothetical phytoplankton ecosystem along a meridional transect from 80◦ N to 80◦ S (note that this is the latitudinal extent of the global model), each with 78 species. Each species range size was chosen at random between a minimum of 0◦ and a maximum of 160◦ in extent. The midp ...
... realizations of a hypothetical phytoplankton ecosystem along a meridional transect from 80◦ N to 80◦ S (note that this is the latitudinal extent of the global model), each with 78 species. Each species range size was chosen at random between a minimum of 0◦ and a maximum of 160◦ in extent. The midp ...
Biodiversity and Climate Change: Integrating Evolutionary and
... Ecology and evolution have developed as separate fields based on the distinction between “ecological time” and “evolutionary time” made by Slobodkin (1961). Hairston et al. (2005) have proposed that rapid evolution should be defined as genetic changes occurring fast enough to have a measurable impact ...
... Ecology and evolution have developed as separate fields based on the distinction between “ecological time” and “evolutionary time” made by Slobodkin (1961). Hairston et al. (2005) have proposed that rapid evolution should be defined as genetic changes occurring fast enough to have a measurable impact ...
Summary
... growth of adult individuals. However, the VBGC give poor adjustment in the case of this species by underestimating the value of growth slope during whole investigation period. The VBGC has the disadvantage of not being accurate for describing first growth years with exception for species, which est ...
... growth of adult individuals. However, the VBGC give poor adjustment in the case of this species by underestimating the value of growth slope during whole investigation period. The VBGC has the disadvantage of not being accurate for describing first growth years with exception for species, which est ...
larval competition differentially affects
... Biological transmission of arboviruses includes acquisition of the virus by the vector from an infectious blood meal, replication, dissemination of virus to the salivary glands, and transmission to a host by bite (Hardy 1988, Higgs 2004). Successful completion of this process requires that infection ...
... Biological transmission of arboviruses includes acquisition of the virus by the vector from an infectious blood meal, replication, dissemination of virus to the salivary glands, and transmission to a host by bite (Hardy 1988, Higgs 2004). Successful completion of this process requires that infection ...
Lack of relationship between below
... vary among species (Wilson & Tilman 1995), yet little is known about which plant traits make different species effective competitors below ground. Much as it has been assumed that plants will increase root allocation in response to root competition, it has also been assumed that root system size is ...
... vary among species (Wilson & Tilman 1995), yet little is known about which plant traits make different species effective competitors below ground. Much as it has been assumed that plants will increase root allocation in response to root competition, it has also been assumed that root system size is ...
A 20-YEAR RECORD OF ALPINE GRASSHOPPER ABUNDANCE
... The only long-term records of grasshoppers (Orthoptera: Acrididae) known to fall within category (b) are the present study over 20 years, and the exceptional 32-year study of Gage and Mukerji (1977, 1978). This Canadian survey annually sampled peak adult populations for the rural districts of every ...
... The only long-term records of grasshoppers (Orthoptera: Acrididae) known to fall within category (b) are the present study over 20 years, and the exceptional 32-year study of Gage and Mukerji (1977, 1978). This Canadian survey annually sampled peak adult populations for the rural districts of every ...
Dispersal and persistence
... Barriers – abiotic or biotic feature that restricts movement of genes or individuals from one place to another • Species-specific • Generally, organisms that inhabit fluctuating environments are more tolerant of extreme/unusual conditions than species in stable habitats ...
... Barriers – abiotic or biotic feature that restricts movement of genes or individuals from one place to another • Species-specific • Generally, organisms that inhabit fluctuating environments are more tolerant of extreme/unusual conditions than species in stable habitats ...
Ecology of a sympatric pair of coregonid fish: Species interactions
... combination of these factors may sufficiently reduce competition and allow coexistence of the two closely related fish species. ...
... combination of these factors may sufficiently reduce competition and allow coexistence of the two closely related fish species. ...
