The Biosphere Ch. 3 Lecture

Procedure Make a list of all the types of organisms, including plants, humans, insects, and so on, that you have seen near your home or school.

Procedure Make a diagram that shows how the organisms on your list interact with one another.

Think About It 1) Which organisms on your list provide energy or nutrients to the others? 2) What would you expect to happen if all the plants on your diagram died? Explain your answer. 3) Why is it difficult to make accurate predictions about changes in communities of organisms?

What Is Ecology?

What Is Ecology? Ecology: the study of how organisms interact with their environment. All organisms must interact with both living and nonliving things that surround them Coined by German biologist Ernst Haeckel in 1866. Based on the Greek word oikos, meaning house.

Biosphere The biosphere contains all portions of the planet in which life exists, including land, water, and air. It is the largest ecological unit/level on Earth.

Biosphere Interdependence of life on Earth contributes to an ever-changing biosphere.

Levels of Organization Ecologists study within different levels of organization. Species: a group of organisms so similar to one another that they can breed and produce fertile offspring.  Studies that focus on a particular type of organism in its environment are at the species level.

Levels of Organization Population: A group of organisms of one species living in the same area. Example: Desert tortoises (Gopherus agassizii) living in the Mojave Desert.

Levels of Organization Community: a group of interacting species living in the same place. Each species in a community has a direct or indirect influence on the others in its environment. Example(쓰지마): Desert tortoises are affected by the status of Joshua Trees which are influenced by California Buckwheat which also affects annual wildflowers which the tortoises eat. Buckwheat also depends on nitrogen from tortoise poop.

Levels of Organization Ecosystem: biotic community together with its physical environment in an integrated unit. Example: The western Mojave Desert foothills.

Levels of Organization Biome: a group of ecosystems that have the same climate and similar dominant communities. Example: Desert (deserts and xeric shrublands)

Ecological Research Observing Experimenting Modeling Often the first step; simple or complex; e.g. What species live here? Experimenting Test hypotheses; in lab or outdoors; control or standard to test against Modeling Over long periods of time or large spaces (e.g. whole biome); a way of understanding/predicting; simulations based on parameters / mathematical formulas from previous known observations and experiments.

Ecological Research Suppose you wanted to know if the water in a certain stream is safe to drink. Which ecological method(s) would you choose, and why? Observing Experimenting Modeling

Ecological Research Give an example of an ecological phenomenon that could be studied by modeling. Explain why modeling would be useful.