REVIEW Carrying capacity Population dynamics Fecundity Biotic potential

1. REVIEW • Carrying capacity • Population dynamics • Fecundity • Biotic potential • Calculating Population change • Open population • Closed population • Three general survivorship patterns • 3 growth models

2. Date of next test - • May 22nd – C-D, 23rd A-B

3. Pike Perch game answers • 1.) Graph

4. 2.) Since pike eat a lot of perch there needs to be many more perch than pike in order for the pike to survive. • 3.) The pike population responds to the population of perch. This means that an increase in perch population will cause an increase in pike populations and vice versa.

5. 4.) If there are no predators, the prey’s population would continue to increase until they run out of food or die from stress due to over-crowding or disease • 5.) Predators are beneficial to prey because they can help control its population and prevent disease or over-crowding.

6. Read through population dynamics graphs and complete it.

8. Some key words used to describe population graphs • S Curve (Sigmoid) / logistic growth • Lag Phase • Log phase • Stationary phase/ Equilibrium • Exponential growth • Limiting factors • Density dependent/independent • Carrying capacity

9. Date of next test - • May 22nd – C-D, 23rd A-B

10. REVIEW • Carrying capacity • Population dynamics • Fecundity • Biotic potential • Calculating Population change • Open population • Closed population • Three general survivorship patterns • 3 growth models

11. Factors Affecting Population Change&Interactions Within Communities

12. Density-Dependent Factors • Density-Dependent Factors • Play a greater role in limiting population growth as the population increases in size • Ex. competition, predation, disease

13. Intraspecific competition • When the individuals of a population of the same species compete for the same resources

14. Density-Dependent Factors: • Predation • A predator catches, kills and consumes prey (of another species). • Helps to regulate the number of prey

15. Density-Dependent Factors • Disease • In dense or overcrowded populations, pathogens are able to pass more easily from host to host

16. Density-Dependent Factors • Allee Effect • When the population density is so low that the species cannot reproduce.

17. Density-Dependent Factors • Minimum viable population size • The smallest number of individuals needed to ensure a population can continue for a given period of time

18. Density-Independent Factors • Density-Independent Factors • Play a role in limiting population growth regardless of population size • Ex. extreme weather, human intervention

19. Density-Independent Factors • Limiting Factor • Any essential resource that is in short supply or unavailable • Determines how much the individual or population can grow (affects the biotic potential) • Ex. light, space, water, nutrients

20. Complete p.g. 9 and first part of 10.

22. Bring laptops next class. • Test May 22nd/ 23rd

23. Review • Density-Dependent Factors • Intraspecific competition • Predation • Disease • Allee Effect • Minimum viable population size • Density-Independent Factors • Limiting Factor

24. Using your textbook (P.g. 675-684) and classmates help, come up with definitions to the following words for your notes.

25. Interactions Within Communities • Community • Interspecific competition • Ecological Niche • Fundamental Niche • Realized Niche • Symbiosis

26. Community • Made up of all populations of different species within an ecosystem • Interspecific competition • When the individuals of different species compete for the same resources • Restricts population growth • A driving force for populations of species to evolve adaptations to continue to use resources

27. Ecological Niche (organism’s “occupation”) • An organism’s biological characteristics, including the use of, and interaction with abiotic and biotic resources in its environment • Fundamental Niche • An organism’s biological characteristics and the set of resources individuals in the population are theoretically capable of using under ideal conditions • Ex. If resources were abundant and no competition existed • Realized Niche • An organism’s biological characteristics and the set of resources individuals in the population actually use under existing environmental conditions

28. Symbiosis • Two species maintain a close, usually physical association • At least one of the species benefits • Includes mutualism, commensalism and parasitism

29. Interactions Within Communities • Types of Symbiotic Relationships: • Mutualism (+/+) • Both organisms benefit • Neither organism is harmed • Obligatory mutualism: neither species can survive without the other

30. Interactions Within Communities • Commensalism (+/0) • One organism benefits and the other organism is unaffected

31. Parasitism (+/-) • One organism (parasite) benefits at the expense of the other organism (host) • Host is harmed but is usually not killed • ~1/4 animal species is thought to be a parasite

32. Symbiosis worksheet

34. Interactions Within Communities • Types of Interspecific Competition • I. Interference competition: fighting over shared resources

35. II. Exploitative competition: consumption of shared resources

36. Interactions Within Communities • Interspecific Competition • Niche overlap means more competition. • Competition declines because: • Population size of the weaker competitor declines • One species may adapt. • Migration

37. Interactions Within Communities • Resource partitioning • Avoidance of, or reduction in, competition for similar resources by individuals of different species occupying different non-overlapping ecological niches • Ex. Anolis lizards • Ex. plants

39. Interactions Within Communities • Predation • interspecific interaction If other prey is available, it alters this cyclical relationship

40. Interactions Within Communities • Canadian lynx-snowshoe hare cycle (10 years)

41. Complete first ½ of p.g. 10, matching

42. Defense Mechanisms

44. Interactions Within Communities • Defence Mechanisms • Plants: morphological defences (thorns, hooks, spines, needles) and chemical defences (distasteful, toxic) • Insects: some use chemicals produced by their food as protection from their predators (ex. monarch butterfly)

45. Interactions Within Communities • Passive Defence Mechanisms • Ex. Hiding • Ex. Camouflage • Ex. Visual warning to predators of chemical defences (poisons) • Ex. Mimicry • Batesian: a harmless species mimics a harmful species

46. Interactions Within Communities • Active Defence Mechanisms • Ex. Fleeing from predators • Ex. Alarm calls • More costly in terms of energy required

48. Interactions Within Communities • Introduction of Exotic (non-indigenous) Species • Can disrupt ecosystems’ dynamic equilibrium and displace indigenous species to such a degree that they impact on the biodiversity in that ecosystem • Since non-indigenous species often have few predators in that area, they can reduce or eliminate indigenous species by outcompeting them for food and habitat, or by preying on them

49. Complete pages 10 – 11 in your population ecology package.