Plasticity of Communication in Nonhuman Primates
... suggesting that vocal divergence may be important to distinguish local populations from each other. They also reported no correlation between acoustic differences and genetic differences in pairs of animals. They suggested that there should be little variation in habitat among the areas of the three ...
... suggesting that vocal divergence may be important to distinguish local populations from each other. They also reported no correlation between acoustic differences and genetic differences in pairs of animals. They suggested that there should be little variation in habitat among the areas of the three ...
Population Dynamics: General Results from Local Analysis Thilo Groß
... reveals a new, general solution to the famous paradox of enrichment. It is shown that enrichment always destabilizes certain ecological models if the interaction is described by simple functions. However, a large class of more complex functions exists which result in more complex model behaviour. If ...
... reveals a new, general solution to the famous paradox of enrichment. It is shown that enrichment always destabilizes certain ecological models if the interaction is described by simple functions. However, a large class of more complex functions exists which result in more complex model behaviour. If ...
Inconsistent impacts of decomposer diversity on the stability of
... (e.g., earthworms) are known to importantly affect the activity of other soil taxa (Brown 1995; Eisenhauer et al. ...
... (e.g., earthworms) are known to importantly affect the activity of other soil taxa (Brown 1995; Eisenhauer et al. ...
Journal of Animal Ecology 82(6) - Seagrass Ecosystems Research
... dugon; sea turtles Chelonia mydas) on seagrass community structure, biomass and nutrient dynamics. Experiments were conducted in habitats with high risk of predation (interior of shallow banks) and lower risk (edges of banks) to elucidate whether nonconsumptive (risk) effects of tiger sharks (Galeoc ...
... dugon; sea turtles Chelonia mydas) on seagrass community structure, biomass and nutrient dynamics. Experiments were conducted in habitats with high risk of predation (interior of shallow banks) and lower risk (edges of banks) to elucidate whether nonconsumptive (risk) effects of tiger sharks (Galeoc ...
Top predators, mesopredators and their prey: interference
... Furthermore, the strength of top predator control of mesopredators may increase with ecosystem productivity (Elmhagen & Rushton 2007). We suggest this could result in ‘interference ecosystems’ where interference divides the predators into two functional groups, top predators and mesopredators. A sec ...
... Furthermore, the strength of top predator control of mesopredators may increase with ecosystem productivity (Elmhagen & Rushton 2007). We suggest this could result in ‘interference ecosystems’ where interference divides the predators into two functional groups, top predators and mesopredators. A sec ...
Form, Function, Food and Feeding in Stellate Echinoderms
... Ophiuroids with multiple arms produced without branching. Hyman (1955) stated that ophiuroids have five (rarely six or seven) arms that are not produced by branching. Several extinct stenurid ophiuroids such as Kentrospondylus (Lower Devonian) had ten arms (Spencer & Wright 1966). Congeneric specie ...
... Ophiuroids with multiple arms produced without branching. Hyman (1955) stated that ophiuroids have five (rarely six or seven) arms that are not produced by branching. Several extinct stenurid ophiuroids such as Kentrospondylus (Lower Devonian) had ten arms (Spencer & Wright 1966). Congeneric specie ...
Steady state solutions of an ecosystem mod
... by micronutrients may be necessary to account for growth rates that seem low by a factor of two (Cullen et al. 1992) as well as to account for the absence of large algal species, which are thought to be more sensitive to low micronutrient levels than species smaller are (Hudson and Morel 1990; Morel ...
... by micronutrients may be necessary to account for growth rates that seem low by a factor of two (Cullen et al. 1992) as well as to account for the absence of large algal species, which are thought to be more sensitive to low micronutrient levels than species smaller are (Hudson and Morel 1990; Morel ...
Bottom-Up and Top-Down Interactions across Aquatic
... Top-down effects of consumers are commonly observed in rocky intertidal ecosystems (Menge, 2000). These may result from consumption, consistent with the mathematical foundation of classic food chain models, or through nonconsumptive effects whereby prey behavior or traits are altered by limiting for ...
... Top-down effects of consumers are commonly observed in rocky intertidal ecosystems (Menge, 2000). These may result from consumption, consistent with the mathematical foundation of classic food chain models, or through nonconsumptive effects whereby prey behavior or traits are altered by limiting for ...
When Does Alternative Food Promote Biological Pest
... of omnivory. Third, we consider spatial structure and ask how the distribution of PPF and prey relative to each other matters to reducing herbivory. Finally, we step beyond consumerresource interactions and ask when food web complexities (omnivory, hyperpredation, intraguild predation, competition) ...
... of omnivory. Third, we consider spatial structure and ask how the distribution of PPF and prey relative to each other matters to reducing herbivory. Finally, we step beyond consumerresource interactions and ask when food web complexities (omnivory, hyperpredation, intraguild predation, competition) ...
Non-Consumptive Effects of Spiders and Ants: Does Fear
... physiology, morphology and behaviour. Spiders are among the most diverse and frequent predators in terrestrial ecosystems. Our behavioural arena experiments revealed that behavioural changes under spider predation risk are relatively scarce among arthropods. Wood crickets (Nemobius sylvestris), in p ...
... physiology, morphology and behaviour. Spiders are among the most diverse and frequent predators in terrestrial ecosystems. Our behavioural arena experiments revealed that behavioural changes under spider predation risk are relatively scarce among arthropods. Wood crickets (Nemobius sylvestris), in p ...
Short-term changes of protozoan control on autotrophic
... 24 h after fixation, and only individuals without plastids (checked for Chi a fluorescence with the 490/510/520filterset) were included in the counts. The length and width of HNF were measured weekly in the epi- and metalimnetic samples on at least 40 individuals per sample, and geometrical approxim ...
... 24 h after fixation, and only individuals without plastids (checked for Chi a fluorescence with the 490/510/520filterset) were included in the counts. The length and width of HNF were measured weekly in the epi- and metalimnetic samples on at least 40 individuals per sample, and geometrical approxim ...
preliminary survey of the relationship between the feeding habit and
... that C. finmarchicus ate the same amount of T. fluviatilis whether 01’ not Artemia were present. When only Artemia were available, a few were eaten, but the feeding decreased greatly in a mixed culture. Thus, it would appear that Calanus is predominantly an herbivore. Acartia tonsa Despite its small ...
... that C. finmarchicus ate the same amount of T. fluviatilis whether 01’ not Artemia were present. When only Artemia were available, a few were eaten, but the feeding decreased greatly in a mixed culture. Thus, it would appear that Calanus is predominantly an herbivore. Acartia tonsa Despite its small ...
True Value of Estuarine and Coastal Nurseries for Fish
... control of nursery populations (Baker and Sheaves 2009b). In addition, these refuge-food acquisition tradeoffs vary between species (Camp et al. 2011) meaning that nursery ground values may differ markedly depending on the species involved. Food Webs (Fig. 1g) Predators have a strong top-down contro ...
... control of nursery populations (Baker and Sheaves 2009b). In addition, these refuge-food acquisition tradeoffs vary between species (Camp et al. 2011) meaning that nursery ground values may differ markedly depending on the species involved. Food Webs (Fig. 1g) Predators have a strong top-down contro ...
Baboons, Space, Time, and Energy The
... habitats—or of two species in a single habiThere are two complementary, but quite tat—attributable to differences in group different approaches to "explaining" social size, numbers of adult males and females organization. One is reductionistic: an ex- per group, group responses to predators, aminati ...
... habitats—or of two species in a single habiThere are two complementary, but quite tat—attributable to differences in group different approaches to "explaining" social size, numbers of adult males and females organization. One is reductionistic: an ex- per group, group responses to predators, aminati ...
Feeding of detritivores in freshwater sediments
... material (e.g. from recently died algae) is deprived of the most nutritious components and only part of the lost biomass is replaced by microbial biomass. Therefore, detritivores probably have to deal with food sources of low nutritional value which will vary with states of degradation and microbial ...
... material (e.g. from recently died algae) is deprived of the most nutritious components and only part of the lost biomass is replaced by microbial biomass. Therefore, detritivores probably have to deal with food sources of low nutritional value which will vary with states of degradation and microbial ...
Relative impacts of copepods, cladocerans and
... Wiackowski et al., 1994), but indirect effects of calanoid copepods on other heterotrophs have not been measured. Jiirgens et al. (1994a) described the effects of Daphnia spp. and mixed copepods (Eudiaptomus and three species of cyclopoids) on the largely heterotrophic, microbial community of a meso ...
... Wiackowski et al., 1994), but indirect effects of calanoid copepods on other heterotrophs have not been measured. Jiirgens et al. (1994a) described the effects of Daphnia spp. and mixed copepods (Eudiaptomus and three species of cyclopoids) on the largely heterotrophic, microbial community of a meso ...
Effects of productivity, disturbance, and ecosystem size on food
... ecosystem size are comparably strong, and the disturbance effect is the weakest (Takimoto and Post, in preparation). Despite these advances in empirical research, there are currently few theoretical attempts to examine and compare the effects of productivity, disturbance, and ecosystem size within a s ...
... ecosystem size are comparably strong, and the disturbance effect is the weakest (Takimoto and Post, in preparation). Despite these advances in empirical research, there are currently few theoretical attempts to examine and compare the effects of productivity, disturbance, and ecosystem size within a s ...
Effects of predatory ants on lower trophic levels across a gradient of
... established ant exclosures in each of the two management types in Belen, with all study plots in Belen Rustic located at least 600 m from plots in Belen Production. Plots in Irlanda and Hamburgo were separated by a minimum of 1 km, and these were separated from plots in Finca Belen by 11 km. We thus ...
... established ant exclosures in each of the two management types in Belen, with all study plots in Belen Rustic located at least 600 m from plots in Belen Production. Plots in Irlanda and Hamburgo were separated by a minimum of 1 km, and these were separated from plots in Finca Belen by 11 km. We thus ...
Trophic roles of heterotrophic nanoflagellates and ciliates among
... During the study period, 5 dominant genera of ciliates were found (Table 1). Judging from the microscopic observation of FLB ingestion by ciliates, we confirmed that Cyclidium spp. and Halteria spp. were consumers of bacteria. Although Cinetochilum sp. is classified as a bacterial consumer in the li ...
... During the study period, 5 dominant genera of ciliates were found (Table 1). Judging from the microscopic observation of FLB ingestion by ciliates, we confirmed that Cyclidium spp. and Halteria spp. were consumers of bacteria. Although Cinetochilum sp. is classified as a bacterial consumer in the li ...
Trophic ecology of meiofauna: Francisco J.A. Nascimento
... chemical conditions of their habitats (Meysman et al. 2006). The community structure of benthic invertebrates is determined by several interacting factors, one of the most important being how individuals acquire nutrients. Most of ocean bottoms are situated below the photic zone, which mean that ani ...
... chemical conditions of their habitats (Meysman et al. 2006). The community structure of benthic invertebrates is determined by several interacting factors, one of the most important being how individuals acquire nutrients. Most of ocean bottoms are situated below the photic zone, which mean that ani ...
Mrs. Krausz`s Environmental Science: Chapter 5 Study Guide
... mountain meadow, grasshoppers and aphids eat the flowers and grasses. Ladybugs eat the aphids, and blue jays eat the grasshoppers and ladybugs. Blue jays also eat grass seeds and pine nuts and even an occasional small frog from the pond. The frogs ate algae in the pond when they were tadpoles, but n ...
... mountain meadow, grasshoppers and aphids eat the flowers and grasses. Ladybugs eat the aphids, and blue jays eat the grasshoppers and ladybugs. Blue jays also eat grass seeds and pine nuts and even an occasional small frog from the pond. The frogs ate algae in the pond when they were tadpoles, but n ...
Habitat structure, trophic structure and ecosystem
... in increased density and diversity because of greater opportunities for specialization or increased likelihood of immigration (MacArthur and Wilson 1967). For example, forest fragmentation in the Amazon results in reduced dung decomposition rates, likely due to reductions in density, species richnes ...
... in increased density and diversity because of greater opportunities for specialization or increased likelihood of immigration (MacArthur and Wilson 1967). For example, forest fragmentation in the Amazon results in reduced dung decomposition rates, likely due to reductions in density, species richnes ...
UvA-DARE (Digital Academic Repository) Feeding of detritivores in
... componentss that are released from decaying organic matter. Benthic microbial activity andd biomass are observed to increase within hours after sedimentation of algae (Graf 1992).. In aerobic environments, aquatic hyphomycetes are dominant during the early stagess of decomposition of plant matter. T ...
... componentss that are released from decaying organic matter. Benthic microbial activity andd biomass are observed to increase within hours after sedimentation of algae (Graf 1992).. In aerobic environments, aquatic hyphomycetes are dominant during the early stagess of decomposition of plant matter. T ...
11 - Amboseli Baboon Research Project
... to feeding, be? with respect anti-predator and social mechanisms, havior, spacing structure." While such classifications may help organize large bodies of data, they must fail as devices. The reason is this: explanatory to there are many different ways exploit food in a rain forest Thus, any habitat ...
... to feeding, be? with respect anti-predator and social mechanisms, havior, spacing structure." While such classifications may help organize large bodies of data, they must fail as devices. The reason is this: explanatory to there are many different ways exploit food in a rain forest Thus, any habitat ...
Food web
A food web (or food cycle) is the natural interconnection of food chains and generally a graphical representation (usually an image) of what-eats-what in an ecological community. Another name for food web is a consumer-resource system. Ecologists can broadly lump all life forms into one of two categories called trophic levels: 1) the autotrophs, and 2) the heterotrophs. To maintain their bodies, grow, develop, and to reproduce, autotrophs produce organic matter from inorganic substances, including both minerals and gases such as carbon dioxide. These chemical reactions require energy, which mainly comes from the sun and largely by photosynthesis, although a very small amount comes from hydrothermal vents and hot springs. A gradient exists between trophic levels running from complete autotrophs that obtain their sole source of carbon from the atmosphere, to mixotrophs (such as carnivorous plants) that are autotrophic organisms that partially obtain organic matter from sources other than the atmosphere, and complete heterotrophs that must feed to obtain organic matter. The linkages in a food web illustrate the feeding pathways, such as where heterotrophs obtain organic matter by feeding on autotrophs and other heterotrophs. The food web is a simplified illustration of the various methods of feeding that links an ecosystem into a unified system of exchange. There are different kinds of feeding relations that can be roughly divided into herbivory, carnivory, scavenging and parasitism. Some of the organic matter eaten by heterotrophs, such as sugars, provides energy. Autotrophs and heterotrophs come in all sizes, from microscopic to many tonnes - from cyanobacteria to giant redwoods, and from viruses and bdellovibrio to blue whales.Charles Elton pioneered the concept of food cycles, food chains, and food size in his classical 1927 book ""Animal Ecology""; Elton's 'food cycle' was replaced by 'food web' in a subsequent ecological text. Elton organized species into functional groups, which was the basis for Raymond Lindeman's classic and landmark paper in 1942 on trophic dynamics. Lindeman emphasized the important role of decomposer organisms in a trophic system of classification. The notion of a food web has a historical foothold in the writings of Charles Darwin and his terminology, including an ""entangled bank"", ""web of life"", ""web of complex relations"", and in reference to the decomposition actions of earthworms he talked about ""the continued movement of the particles of earth"". Even earlier, in 1768 John Bruckner described nature as ""one continued web of life"".Food webs are limited representations of real ecosystems as they necessarily aggregate many species into trophic species, which are functional groups of species that have the same predators and prey in a food web. Ecologists use these simplifications in quantitative (or mathematical) models of trophic or consumer-resource systems dynamics. Using these models they can measure and test for generalized patterns in the structure of real food web networks. Ecologists have identified non-random properties in the topographic structure of food webs. Published examples that are used in meta analysis are of variable quality with omissions. However, the number of empirical studies on community webs is on the rise and the mathematical treatment of food webs using network theory had identified patterns that are common to all. Scaling laws, for example, predict a relationship between the topology of food web predator-prey linkages and levels of species richness.