1. Chapter 18

2. Ecology Symbiotic Relationships
Symbiotic—long term association between two species

3. Literal definition: the act of living together
What is symbiosis?
Literal definition: the act of living together
What it means:
Two organisms that live together
Temporarily or for a longer time
At least one of the organisms benefits from the relationship

4. Types of Symbiotic Relationships
COMMENSALISM
MUTUALISM
PARASITISM

5. Parasitism “Good for me, hurts you!” Example: Cuckoo and Warbler
Deer and Tick
A cuckoo may lay its eggs in a warbler’s nest. The cuckoo’s young will displace the warbler’s young and will be raised by the warbler.
A tick feeds on deer blood to the detriment of the deer.

6. Parasitism—one organism benefits while the other is harmed Ex. Mosquito

7. “Good for you, good for me!
MUTUALISM
“Good for you, good for me!
Example: Ostrich and Gazelle
These two animals feed next to each other in the grasslands. Both watch for predators and alert each other to danger. The visual abilities of these two animals are different so they are able to identify threats the other animal would not see.

8. Mutualism—two organisms that benefit from each other Ex. Clown Fish

9. COMMENSALISM “Good for me, doesn’t bother you!
Example: Hermit Crab and Snail
Remora and Shark
A hermit crab lives in shells that are made and then abandoned by snails. This neither harms nor benefits the snail.
A remora attaches themselves to a shark’s body. They travel with the shark and feed on the left over food from the shark’s meals. This does not hurt or help the shark.

10. Commensalism—one organism benefits, while the other is unaffected Ex
Commensalism—one organism benefits, while the other is unaffected Ex. Remora

11. Commensalism: one benefits, one is unaffected
Example 4: Clown fish with anemone
Clown fish gets protection Anemone is unaffected
Commensalism: one benefits, one is unaffected

12. Chapter 18-2—How Competition Shapes a Community
Competition—is when two species use the same resource. These resources include food, nesting sites, living space, light, mineral nutrients, and water.
For competition to occur these resources must be in short supply.
Ex. Africa Lions and Hyenas compete for prey

13. Niche—is the functional role of a particular species in and ecosystem
Niche—is the functional role of a particular species in and ecosystem. This is the “job” that organism does.
Not a habitat, which is location versus a niche, which is a pattern of living. Niche is based off such items as food consumption, reproduction, range of space taken.
Ex. Fig A jaguar’s niche (Diet, reproduction, time of activity)

14. Ecological Niche
A plant's or animal's ecological niche is a way of life that is unique to that species.
Niche and habitat are not the same. While many species may share a habitat, this is not true of a niche. Each plant and animal species is a member of a community.
The niche describes the species' role or function within this community.

15. Community
Community - all the species in a given area. Example - all the living things in Lake St. Clair

16. Fundamental Niche—is the entire range of conditions an organism is potentially able to occupy.
The actual part of the fundamental niche a species occupies is called its realized niche.
Ex. Figure 18-5 Warbler locations on the same tree.
Competition can limit the location of species. Limit food supply and space. May even lead to extinction.

17. Predator—hunter for food
Prey—hunted and eaten by others
Distribution of Life
Biosphere—life on Earth that exists in a thin layer of soil, water, and air
Average Range: 8 km deep in the ground to 8 km high in the air

18. Abiotic factors—non living aspects of the atmosphere

19. To study Ecology involves…
For non-living (abiotic)
Climatology
Hydrology
Oceanography
Physics
Chemistry
Geology
soil analysis, etc.
For living (biotic)
animal behavior
Taxonomy
Physiology
mathematics (population studies)
etc.

20. Biosphere can be divided into units called biomes.

21. The location of the tropical biomes.
Figure 8.3

22. The location of the temperate biomes.
Figure 8.13

23. Temperature deciduous forest
Only in N Hemisphere
Climate
Moist but temperate all yr, a few months above 10oC
Soils
Brown earth molisols – rich soil fauna and nutrients
Under conifers soils become leached – podzols – heathland results
Ecology
Mainly deciduous trees, some epiphytes
Four layers (canopy, shrub layer, field layer, ground layer) – dependent on species comprising the canopy
Very marked seasonality of vegetation - creates succession of dominants
Flowering trees and plants – assists wind pollination
Animals may hibernate and burrow to avoid winter effects
MASSIVE HUMAN IMPACTS – reduced coverage and species

24. The deciduous woodland edge
The deciduous woodland edge. Photographed in late spring, this picture shows how ground layer plants, such as bluebells, are spring flowering, to enable the main part of their reproductive cycle to be complete before the tree canopy closes.
Figure 8.17
Source: Photo courtesy of Joseph Holden

25. The location of the cold biomes.
Figure 8.18

26. Biome—a geological region with characteristic group of plants and animals
–usually name by type of vegetation
Example:Tundra, Taiga, Temperate deciduous forest, temperate rain forest, grasslands, and tropical rain forest

27. Aquatic biomes—bodies of water such as lakes, rivers, and oceans
Aquatic biomes—bodies of water such as lakes, rivers, and oceans. Identified by their abundant animal populations.
Polar regions—Extreme northern and southern regions; usually solid ice (30km thick)