1. Biology 307 – Ecology and Human Affairs
Instructors: Dr. Jana Vamosi (BI 238A)
&
Dr. Larry Linton (BI 276C)
Textbook: Ecology of a Changing Planet, 3rd edition
Mark B. Bush

2. More important info: Notes can be obtained from:
me for questions at:
Marking is going to be based on:
1 midterm (Feb. 28th) %
1 final (non-cumulative) ---50%

3. Outline Introduction to Ecology Evolution and Natural Selection
Physiological Ecology
Behavioural Ecology

4. Outline Introduction to Ecology Evolution and Natural Selection
Physiological Ecology
Behavioural Ecology

5. Introduction to Ecology
Chapter , Bush

6. Introduction to Ecology
What is Ecology?
The Scientific Method
Ecology versus Evolution

7. What is Ecology?
The science that attempts to understand the distribution and abundance of organisms
e.g., why are dandelions abundant in some areas, but virtually absent from other areas?

8. Dandelion Distribution
vs.
soil characteristics?
herbivores?
seed dispersal?

9. What is Ecology?
Some questions get at the question of the distribution and abundance of organisms in a more indirect manner
e.g., what determines which male proboscis monkeys will mate and which will not?

10. Mate choice in the Proboscis monkey

11. vs. Environmental Science
The scientific study of the influence of human actions on natural processes
e.g., how is the rattlesnake’s distribution affected by ranching?

12. vs. Environmentalism
concern over changes to the environment due to human action
not science
e.g., how can we encourage hikers to stay on marked trails in mountain meadows?

13. Introduction to Ecology
What is Ecology?
The Scientific Method
Ecology versus Evolution

14. The Scientific Method. I.
starting point: observation(s) of a natural phenomenon
hypothesis is proposed to explain phenomenon & predictions made
hypothesis tested (typically with experiments) & results obtained

15. The Scientific Method. II.
interpret results to determine whether they are consistent with hypothesis
yes? hypothesis supported; no? hypothesis rejected
N.B. hypotheses never proven, only supported

16. Example
Hypothesis:
Plant species with fleshy fruits have heavier seeds than plant species with dry fruits

17. Collect data Fleshy Dry
Spondias radlikoferi(1.93g) Cordia alliodora (0.009g)
Carica papaya (0.011g) Albizia purpusii (0.03g)
Ficus insipida (0.002g) Senna multijuga (0.20g)
mean seed weight (Fl) mean seed weight (Dr)

18. Scientific method and experiments
The previous example did not involve an experiment
Ecological questions can be approached in a variety of ways (comparative, experimental)
An experiment involves a manipulation of some sort

19. Example of an experiment
Hypothesis:
Bearberry plants with fewer flowers will have heavier fruits

20. Experimental design:
make two groups of equal number of bearberry plants
In one group, leave plants alone (control group)
In the other, cut off some flowers (treatment group)

21. Data collection and analysis:
Measure the weights of fruit in the plants in the control and treatment groups
If weight(control) < weight(treatment), you have found support for your hypothesis (fewer flowers leads to larger fruit)

22. Hypothesis  Theory
hypotheses are tentative explanations for an observed phenomenon
theories are widely accepted explanations that are broad in scope and have a large body of evidence supporting them

23. Introduction to Ecology
What is Ecology?
The Scientific Method
Ecology versus Evolution

24. What is Evolution?
EVOLUTION: genetic changes within a lineage or population that result in population-level phenotypic changes
PHENOTYPE: the “appearance” of an organism e.g., physiology, anatomy, behaviour; the expression of the genes that have been inherited from the parent.

25. Ecology versus Evolution
Ecology and evolution are tightly linked
Both ecology and evolution seek to answer the common question of why is the natural world organized as it is
Ecology seeks the more proximate answer while evolution seeks the ultimate answer (i.e., there is a historical element to evolutionary questions)

26. Dandelion Distribution
vs.
A pattern of potential interest to both ecologists and evolutionary biologists

27. Example – dandelion distribution
ecologist might measure how abiotic (e.g., sunlight) and biotic (e.g., herbivore density) factors in the two habitats affect dandelions
evolutionary biologist might search for phenotypic traits in the dandelion that may (a) increase ability to survive in the first habitat or (b) prevent colonization and persistence of dandelions in second habitat

28. Summary
Ecology is an investigative science that relies on the scientific method
The scientific method requires observation, creation of a hypothesis, and data collection to refute or support the hypothesis.
Ecology and evolution are two separate disciplines that overlap in their investigation of the natural world.