Search results
Results From The WOW.Com Content Network
The number of trophic links per consumer is a measure of food web connectance. Food chains are nested within the trophic links of food webs. Food chains are linear (noncyclic) feeding pathways that trace monophagous consumers from a base species up to the top consumer, which is usually a larger predatory carnivore. [8] [9] [10]
Tertiary consumers, which are sometimes also known as apex predators, are hypercarnivorous or omnivorous animals usually at the top of food chains, capable of feeding on both secondary consumers and primary consumers. Tertiary consumers are usually the largest, strongest and most aggressive animal in the local environment. Both secondary and ...
That is, the consumer trophic level is one plus the weighted average of how much different trophic levels contribute to its food. In the case of marine ecosystems, the trophic level of most fish and other marine consumers takes a value between 2.0 and 5.0.
The primary consumer may be eaten by a secondary consumer, which in turn may be consumed by a tertiary consumer. The tertiary consumers may sometimes become prey to the top predators known as the quaternary consumers. For example, a food chain might start with a green plant as the producer, which is eaten by a snail, the primary consumer.
In a temperate grassland, grasses and other plants are the primary producers at the bottom of the pyramid. Then come the primary consumers, such as grasshoppers, voles and bison, followed by the secondary consumers, shrews, hawks and small cats. Finally the tertiary consumers, large cats and wolves.
For example, in a pond ecosystem, the standing crop of phytoplankton, the major producers, at any given point will be lower than the mass of the heterotrophs, such as fish and insects. This is explained as the phytoplankton reproduce very quickly, but have much shorter individual lives.
Trophic cascades are powerful indirect interactions that can control entire ecosystems, occurring when a trophic level in a food web is suppressed. For example, a top-down cascade will occur if predators are effective enough in predation to reduce the abundance, or alter the behavior of their prey, thereby releasing the next lower trophic level from predation (or herbivory if the intermediate ...
Consumer–resource interactions are the core motif of ecological food chains or food webs, [1] and are an umbrella term for a variety of more specialized types of biological species interactions including prey-predator (see predation), host-parasite (see parasitism), plant-herbivore and victim-exploiter systems.