Interactions in Ecology: Understanding Relationships in the Environment

1. Chapter 18 Interactions of Living Things

2. What is Ecology? • The study of the interactions between organisms and their environment • Interactions between organisms is not simply who eats who but varied, some good some bad

3. 2 parts of ecology • Biotic aspect • The living part of the environment • Animals, plants, insects, humans • Abiotic aspect • The non-living part of the environment • Physical factors • Rocks, water, soil, light, temperature

5. Organism Populations Communities Ecosystems Biosphere Single animal Group of the same animal Different populations in the same area Includes the abiotic factors Earth where life exists Organization in the Environment

7. The Energy Connection • All living things need energy to survive • Organisms are divided into groups based on how they get energy • Producers • Consumers • Scavengers • Decomposers

8. Producers • Make their own food/energy • Use the sun to go through the process of photosynthesis • Includes plants, algae and some bacteria

9. Consumers • Can’t make their own energy, get it by eating producers or other consumers • Primary consumer – eats the producer • Secondary consumer – eats a consumer • Herbivore – eats only plants • Carnivore – eats only animals • Omnivores – eats both plants and animals

10. Scavenger vs. Decomposer • Scavengers eat dead animals for energy • Examples include turkey vultures • Decomposers get energy by breaking down the remains of dead organisms • Recyclers, bacteria and fungi

12. Food Chains and Webs • Food chains represent how energy flows from one organism to the next • Rare in nature because animals usually eat more than one organism Food webs represent many pathways that energy flows in an ecosystem

14. Represents the loss of energy by each organism in a food chain or web Energy Pyramids

15. Habitat vs. Niche • Habitat – the environment in which an organism lives • When things like deforestation, building of roads and buildings occur, habitats are being destroyed • Niche – organisms way of life in the ecosystem • Includes its habitat, food, predators, competitors and abiotic factors

16. Niche of the Gray Wolf • Consumers • Carnivores, eating moose, deer, reindeer, sheep and small animals such as birds and snakes • Social Structure – hunt in packs • Nurture and teach their young • Important in population control

17. Interactions • Most living things produce more offspring than will survive but abiotic and biotic factors will control the population size • Example: frogs

18. Limiting factors • Populations cannot grow indefinitely because the environment contains only so much food, water, living space and other resources • When one or more becomes scarce, it becomes a limiting factor

19. Carrying Capacity • The largest population that a given environment can support over a long period of time • When the population gets larger than carrying capacity, limiting factors will cause the population to get smaller

21. Competition • Can occur among individuals within a population or between populations • Competition for resources, mates, space

22. Predator and Prey • Prey – the organism that is eaten • Predator – the organism doing the eating • Adaptations • Predator – speed or ambush prey • Prey – run away, camouflage, poisonous, bright colors, groups

24. Symbiosis • Long term, association between two or more species • 3 types • Mutualism • Commensalism • Parasitism

25. Mutualism • Both organisms benefit • Insects pollinating flowers

26. One organism is benefiting and the other is unaffected Clown fish and sea anemone Commensalism

27. One organism is harmed and the other is benefiting Parasite- benefits Host - harmed Parasitism

28. Coevolution • Long term change that takes place in two species because of their close interactions with each other • Herbivores evolving with the plants they eat • Flowers and their pollinators