Bio 181 1st Edition Lecture 15EcologyPast LectureI. PopulationII. Principles of ecology and HUMAN populations:Current LectureI. 4 major types of interspecific interactions:II. Communities change over timeI. 4 major types of interspecific interactions:A. intersepecific: refers to different species interaction which is negative for both1. Competitiona) leads to species having an ecological niche, which refers to its role in the ecosytem. (1) carnivores and herbivoire contribute to the ecosytem is a good example of their niche. (2) Habitat looks at where an organisms lives while niche looks at what they do and how they contribute to the community.b) When two species compete for a certain resources it will destroy the other for that resource. (1) competition exclusion principle: Species occupying similar niches and competing for the same resouces cannot coexist.c) Fundamental niche- exams the potential of a certain resource and how it could be available to an organism. d) While realized niche- understands what resoucres are actually available at the timee) Allopatric species, those that are related closley but seperate by geographyf) sympatric- population in close geographic proximity,(1) character displacement, due to environment and resource availablilty2. Predationa) predator prey relationship, which is beneficial to predators onlyb) predators use methods such as comouflage to hide themselves fromprey or blend in with certain food sources of the prey to attract it, then attack.c) coevolution then begins to take place such as animals mimicing different plants or animals to seem poisonous to predators.d) Predation also helps maintain a healthy ecosystem. when agouti eats palm tree seeds, they sometimes bury them and save them for later, however ocelot feed on agouti. So those seeds left allow for more palm trees to growe) Another example is the wolves in Yellowstone park and the need for their predator prey relationship. (1) Wolves killing support more scavengers, beaver recolonized the streams, pronghorn then lost fewer calves to coyote -increased streamside vegetation reduced erosion,provided cover for birds, fish, and other animalesf) Animals can also avoid predation with mutiple methods. Coloration used to look like a deadly animal, living in groups, disruptive coloration, playind dead.(1) Mimicry is a good example of these skills(2) Mullerian mimicry where several well-protected species resemble each other.(a) ex: common wasp and bumblebee.(3) Batesian mimicry, is where unprotected species resemble harmful ones.(a) coral snake and king snake, hard to tell which is posinous 3. Parasitism: one species benefits while causing harm to another. a) This can be seen in pathogenic diseases like malaria caused by mosquitos. b) Bacteria, fungi, protists and other viruses are nown as microbial pathogens4. Symbiosis: close association between two or more speciesa) mutualism: both species benefits(1) example, fungi causing plant growth known as mycorrhizae.b) Commensalism: looks at how one species benefits and the other is not affected. (1) ex: birds nesting in trees not cauusing problems for the trees(2) ex: The remora forms a special relationship with sharksII. Communities change over timeA. Disturbance in communities can be removal of other organisms, which can be caused by alter resources or lead to altered resources.B. Human and natural activity are mainly examed when looking at disturbance1. Ecological successsion takes place when communities change over time and different plants and animals become more dominant in an area.a) Primary succession happens in a newly formed lifeless place begining with soil formation. b) While secondary succession occurs in disturbes areas and is typically faster because soil already existed.C. Eutrophication seen in lakes, ponds areas where nutrient enrichment causes increase in plants or algea, and water qualitity declines and pant and soil takes over.1. can be caused by too much human use of