Ecosystems & Populations
description
Transcript of Ecosystems & Populations
![Page 1: Ecosystems & Populations](https://reader036.fdocuments.net/reader036/viewer/2022062323/56815ecf550346895dcd599e/html5/thumbnails/1.jpg)
Ecosystems & PopulationsChapters 4 & 5
![Page 2: Ecosystems & Populations](https://reader036.fdocuments.net/reader036/viewer/2022062323/56815ecf550346895dcd599e/html5/thumbnails/2.jpg)
Levels of Organization in Ecology
• Ecologists study individual organisms, but this only provides part of the story of its life cycle.
• An individual organism interacts with others of its species; it is also dependant on other organisms for food, shelter, reproduction and protection.
![Page 3: Ecosystems & Populations](https://reader036.fdocuments.net/reader036/viewer/2022062323/56815ecf550346895dcd599e/html5/thumbnails/3.jpg)
Levels of Organization in Ecology cont.
• Population – a group of organisms of one species that interbreed and live in the same place at the same time
• Members of the same population may compete with each other for food, water, and other resources.
• How organisms share the resources determines how far apart organisms live and the size of the population.
![Page 4: Ecosystems & Populations](https://reader036.fdocuments.net/reader036/viewer/2022062323/56815ecf550346895dcd599e/html5/thumbnails/4.jpg)
Levels of Organization in Ecology cont.
• Community – a collection of interacting populations
• A change in one population in a community will cause changes in the other populations.
![Page 5: Ecosystems & Populations](https://reader036.fdocuments.net/reader036/viewer/2022062323/56815ecf550346895dcd599e/html5/thumbnails/5.jpg)
Levels of Organization in Ecology cont.
• Ecosystem – made up of the interactions among the populations in a community and the community’s physical surroundings
• Terrestrial, freshwater and saltwater (marine) ecosystems are the three major kinds.
![Page 6: Ecosystems & Populations](https://reader036.fdocuments.net/reader036/viewer/2022062323/56815ecf550346895dcd599e/html5/thumbnails/6.jpg)
Levels of Organization in Ecology cont.
• Biome – a large region characterized by a specific climate and certain plants and animals
• Biosphere – the portion of Earth that supports life
• The biosphere extends from high in the atmosphere to the bottom of the ocean.
![Page 7: Ecosystems & Populations](https://reader036.fdocuments.net/reader036/viewer/2022062323/56815ecf550346895dcd599e/html5/thumbnails/7.jpg)
Organisms in Ecosystems
• Habitat – the place where an organism lives out its life
• Niche – the role and position a species has in its environment – how it meets its needs for food and shelter, how it survives and how it reproduces.
![Page 8: Ecosystems & Populations](https://reader036.fdocuments.net/reader036/viewer/2022062323/56815ecf550346895dcd599e/html5/thumbnails/8.jpg)
Niche
• Several species may share a habitat, but the food, shelter, and other resources of that habitat are used in different ways.
• These differences lead to reduced competition.
• It is an advantage for a species to occupy a niche different from those of other species.
![Page 9: Ecosystems & Populations](https://reader036.fdocuments.net/reader036/viewer/2022062323/56815ecf550346895dcd599e/html5/thumbnails/9.jpg)
Living Relationships• Predator-Prey
Relationship – beneficial for one species and harmful to another, involves a fight for survival.
• However, some species enhance their chances of survival by forming close, permanent relationships with other species - symbiosis.
![Page 10: Ecosystems & Populations](https://reader036.fdocuments.net/reader036/viewer/2022062323/56815ecf550346895dcd599e/html5/thumbnails/10.jpg)
Symbiotic Relationships
• Commensalism –relationship in which one species benefits and the other species is neither harmed nor benefited
• The clownfish lives among the stinging tentacles of an anemone and is protected from potential predators not immune to the sting of the anemone.
![Page 11: Ecosystems & Populations](https://reader036.fdocuments.net/reader036/viewer/2022062323/56815ecf550346895dcd599e/html5/thumbnails/11.jpg)
Symbiotic Relationships cont.
• Mutualism – relationship in which both species benefit
• Some fish and shrimp clean the bodies and mouths of large fish and turtles.
• The cleaner fish get a meal while the large fish have parasites removed.
![Page 12: Ecosystems & Populations](https://reader036.fdocuments.net/reader036/viewer/2022062323/56815ecf550346895dcd599e/html5/thumbnails/12.jpg)
Symbiotic Relationships cont.
• Parasitism – relationship in which one organism derives benefit at the expense of the other.
• Ticks are parasites of animals like dogs, obtaining nutrients from the blood of their host.
• Parasites harm, but usually do not kill, the host.