BIOL 2060 Lecture 25: food webs
19 Apr 2016
School
Department
Course
Professor
Document Summary
Maps summarize feeding relationships among species: who eats who. Diversity is lower food web more simple. Detritus: recycling of organic material to be reused in the food chain: ex. Parasite kills predator, predator carcass used by lower trophic levels. Represents number of linkages in the food web: describes the position of a species in a food web. Herbivores always level 2 only feed on level 1. Can usually have up to 5 trophic level in a web. Many species present: web represent only about 30% of species and 11% of interactions. Total of 249 species and 3313 interactions: thicker arrows are strong interactions, thinner lines are weaker interactions. Parasites and bacteria often difficult to observe and quantify. Habitat usually not incorporated: interactions between species and their environment. Connection diversity: some interactions/connections are stronger than others. Structural complexity: network can be an intricate tangle of interactions. Network evolution: the network can change over time.
