1. Interactions of Living Things
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. Organization in the Environment
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

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

9. Consumers Primary consumer – eats the producer
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
Represents the loss of energy by each organism in a food chain or web

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

22. Prey – the organism that is eaten
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. Long term, association between two or more species 3 types
Symbiosis
Long term, association between two or more species
3 types
Mutualism
Commensalism
Parasitism

25. Both organisms benefit Insects pollinating flowers
Mutualism
Both organisms benefit
Insects pollinating flowers

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

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

28. Herbivores evolving with the plants they eat
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