an inadvertent opening ramble about networks. predation is a straight-forward interspecies...

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an inadvertent

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an inadvertent opening ramble about networks

Predation is a straight-forward interspecies population interaction. One species uses another as a food resource. Predators play an important role in controlling prey population numbers in some systems. In simple systems, the predator-prey relationship results in coupled population osscilations

Classic example of predator-prey dynamics: Canadian lynx & snowshoe hare

Coupled oscillation

• prey numbers increase, predator numbers increase…to a point where the predation causes population decline in the prey item..

These dramas are the (proverbial) tip of the iceberg. Ecological community interactions are extremely complex…

Herbivores, that are competing, and also prey items

Predators, that are NOT directly interacting, but are ecologically interdependent

Here is the ecological story: In competition, the larger Daphnia will outcompete the smaller Daphnia. The salamanders eat the larger Daphnia, allowing the smaller Daphnia to persist. The midge can ONLY eat the smaller Daphnia. Thus, where the salamander larva is present, the midge larva do well… because they control the population of the midge prey’s competitor.

example of a typical ecological interaction?

example of a typical ecological interaction?

resource

30 boxes, one form of interaction… = 28 million pathways…

What do we do with systems where there are multiple modes of interaction, and more species (LCW = 300 species of herbaceous plant)