Key Vocabulary words: Know these definitions:
Ecological hierarchy
Ecosystem
Habitat
Community
Population
Species
Niche
Ecological interactions:
competition
predation
symbiosis
Ecological health:
Biodiversity
ECOLOGICAL HIERARCHY:
The living organisms on the earth can be organized in different groups, or divisions. The biggest division is the biosphere itself, that thin layer of soil, water and air and all the life within it. The other divisions fit within that biosphere. Like russian dolls, each division fits within another: For example
If we look at the biosphere as a group of living things, then the russian dolls are labeled like this:
Ecological Hierarchy of interaction
BIOSPHERE
biomes
ecosystems
communities
populations (made up of the same species).
organisms (of the same species)
If we look at the biosphere as a place, the russian dolls are labeled like this:
Hierarchy of a place called BIOSPHERE
biomes
ecosystems
habitats
ECOSYSTEMS:
We will focus on the Ecosystem, a network of interacting organisms linking biotic factors and abiotic factors. It is a system in equilibrium. It is dynamic, yet unchanging over a long period of time.
Ecosystems can be considered a group of living things who happen to be in the same place at the same time, like a group of friends hanging out together. Yet, we can also consider ecosystems a place. For example, a forest ecosystem is both a group of organisms and a place. Can you picture a forest as a group of trees, ferns, bushes, microbes, fungi...all interacting? Yet a forest is also geography: We have a forest called Pacific Spirit Park, an ecosystem named Camosun bog, another one called Trout Lake.
And ecosystems are dynamic, ever changing. Over time, organisms move in, move out. They mate, and have offspring and die. Yet ecosystems seem to stay the same: a forest may have the same species inventory for over 300 years.
Examples of ecosystems (they are like minibiomes within the big biome!):
west coast rainforest, desert, bog, micro ecosystem within the human gut!
Biodiversity:is the number of different organisms within any ecosystem...the more the better!
What happens inside ecosystems Here are a few of the interactions within that ecosystem:
1. Competition: organisms may compete for the same resources such as food, mates, territory
2. Predation: some organisms eat others: A game of tag with very high stakes.This affects their population dynamics. And their adaptations are exquisitely tuned to the task of hunting, killing, or running and escaping.
3. Symbiosis: some organisms live closely with others as a host/symbiont pair:
a. parasitism
b. mutualism
c. commensalism
Homework: Do the study guide questions for section 1.2 including the sample multiple choice questions. Note that some of these are tricky!
Your homework quiz for this section is here:
HOMEWORK QUIZ
Note that I must wait for all responses to come in before marking them.
