Chapter 1 - Introduction to Ecology

Ecology

The study of the relationships between organisms and their environments

Consists of a variety of aspects;

-Natural history

-Biotic/Abiotic

-Lab to field

-Physiological to global scale

-Millisecond to millenial scale

-Scientific method

Levels of Ecology

Organismal - the individual/autoecology

Population - Group of interbreeding individuals of a single species inhabiting an area

Community - An association of interacting species

Ecosystem - Biological community consisting of multiple communities interacting

Landscape - The exchange of materials/energy/organisms across communities and ecosystems

Biosphere - Takes multiple landscapes/portions of the Earth into account (global ecology)

Temporal Scale

A given timeframe/passing of time

a) milliseconds to years (fine scale)

-Ex; examining photosynthesis in plants

b) centuries to millenia (coarse scale)

-lifetime output of the plant itself

Requires different methods to study based on the time period

Paleoecologists

Study the data from fossils and reconstruct ecosystems from the past using historical data

Experiment Types

Observational Research - Data collection is obtained through observing a species

-In Situ - observation that takes place in the habitat where the organism lives

-Ex-Situ - research that takes places outside of the organism’s natural habitat

Experimental Research - research that involves the manipulation of variables of interest

MacArthur Warbler Study

Example of in-situ observational research

-Studied 5 warbler species in spruce forests of North America

-His theory predicted that, because they have identical ecological requirements, they’d be unable to coexist indefinitely

-In actuality, they all coexist but occupied different feeding zones of the trees they lived in (top, middle, inside, bottom, etc)

David Schindler Lake Erie Study

Example of experimental research

-in 1971, agricultural runoff from industry resulted in much of the death of Lake Erie, but this had to be proven

-David Schindler had a theory that the phosphorus killed the ecosystem within the lake

-Divided a different lake into two sections, one with phosphorus and the other without

-The section containing higher concentration of phosphorus died out, the other remained stable

Change in Environments

Environmental changes occur over large spatial or temporal scales (ex; climate change)

-Difficult to study due to variety of changes and unknown factors in the future

-Right research tools and a detailed knowledge of biology is necessary to predict these changes

Measuring Vegetation Records

Palynology - Study of Pollen

Pollen is preserved well in lakes, using historical records you can detect which pollen was present/absent in a specific time in history

-Sediment from the nearby Appalachian mountain is swept into the lake

-This sediment contains pollen

-By uncovering the sediment, you can detect changes in pollen and therefore changes in the landscape

David monitored plant pollen deposited from the mountains, discovered large temporal changes

-Pollen present earlier in history is located deeper in the sediment

Jackrabbits

-Beginning to show up more in urban centres, more north of their range likely due to climate change impacting their geographies

-Wildlife-friendly planning is a method to protect their habitats

Scientific Method

When an interesting question is formed, we form a testable hypothesis to answer it

1. Original question - Acts as the ‘guiding light’ of the scientific process

2. Hypothesis - many variations/alternatives, provides a testable prediction

3. Test Prediction - determines the validity of the hypothesis

4. Testing of Hypothesis - Through observations, experimentation, or modelling we collect data that will then be analyzed (statistics, etc) in order to accept or reject the hypothesis

Ecologist

Person who applies a scientific approach to understanding the relationship between organisms and the environment