1. Ch. 51 Review Matching: A.Classical conditioning B.Operant conditioning C.Habituation D.Fixed action pattern E.Imprinting 1.Birds exposed to a full song in a critical period cause development of the same song 2.Prairie dogs who live near hiking trails do not give alarm calls every time a person walks by 3.Your dog learns to shake hands with you when you hold out your hand after being rewarded with treats 4.A rat learns how to get through a maze when it is rewarded with a treat, but never obtains food if it makes a mistake 5.A baby duck runs for cover when an object is thrown over its head, but stops running after many trials

2. Ch. 53 Warm-Up 1.Sketch an exponential population growth curve and a logistic population growth curve. 2.What is an ecological footprint? 3.What are ways that you can reduce your ecological footprint?

3. POPULATION ECOLOGY Chapter 53

4. You Must Know: How density, dispersion, and demographics can describe a population. The differences between exponential and logistic models of population growth. How density-dependent and density- independent factors can control population growth.

5. Population = group of individuals of a single species living in same general area Rely on the same resources, Interact, and Interbreed Introduction

6. Characterizing a Population Population Size - changes to the # of organisms in a population Involves adding & removing individuals Birth rate Death rate Immigration Emigration

7. Characterizing a Population Density - # of individuals per unit of area or volume Count the # of individuals Mark-Recapture Method Also affected by birth rates, death rates, immigration, and emigration density

8. Characterizing a Population Dispersion- spacing patterns within a population Provides insight into the environmental associations & social interactions of individuals in population

9. Clumped Pattern (most common)

10. Uniform May result from direct interactions between individuals in the population territoriality

11. Random Unpredictable patterns – no strong attraction or repulsion between the individuals

12. Patterns of Dispersal: 1. Clumped – most common; near required resource 2. Uniform – usually antagonistic interactions 3. Random – not common in nature

13. Characterizing a Population Population Range - geographical limitations of a population Abiotic & biotic factors such as temperature, rainfall, food, predators, etc. Organisms have adaptations specific to their habitat adaptations to polar biome adaptations to rainforest biome

14. Changes in Range Range expansions & contractions changing environment

15. At Risk Populations Endangered species are greatly affected by changes in range The more limited their range / habitat the more at risk the organisms are to extinction Iriomote cat New Guinea tree kangaroo Northern white rhinoceros Socorr o isopod Catalina Island mahogany tree Iiwi Hawaiian bird Devil’s hole pupfish

16. Additions occur through birth, and subtractions occur through death. Life table : age-specific summary of the survival pattern of a population Represent data with a survivorship curve. Plot # of individuals in a cohort still alive at each age. Demography: the study of vital statistics that affect population size

17. Life Table

18. Population Growth Rates Survivorship Curves - graphic representation of life table The relatively straight lines of the plots indicate relatively constant rates of death; however, males have a lower survival rate overall than females.

19. Survivorship Curves: Type I curve: low death rate early in life (humans) Type II curve: constant death rate over lifespan (squirrels) Type III curve: high death rate early in life (oysters)

20. Population Growth Rates Factors that affect population growth rates: sex ratio how many females vs. males? generation time at what age do females reproduce? age structure How many cohorts (groups that are the same age) of females are able to reproduce?

21. Trade-offs: Survival vs. Reproduction Reproduction has a cost… increase reproduction may decrease survival investment per offspring (how many offspring are produced and how much parental care is necessary) reproductive events per lifetime (how often they reproduce) when reproduction begins - age at first reproduction or at maturity Natural selection favors a life history that maximizes lifetime reproductive success

22. Parental Survival Kestrel Falcons: The cost of larger broods to both male & female parents

23. Reproductive Strategies Semelparity Big-bang reproduction Many offspring produced at once Individual often dies afterwards Less stable environments Selected by organisms rate of growth  r-selected Fish, bugs and plants Agave Plant

24. Reproductive Strategies Iteroparity Repeated reproduction Few, but large offspring More stable environments Selected by carrying capacity  k-selected Mammals, birds, etc Lizard Critical factors: survival rate of offspring and repeated reproduction when resources are limited

25. K-selection : pop. close to carrying capacity r-selection : maximize reproductive success K-selectionr-selection Live around KExponential growth High prenatal careLittle or no care Low birth numbersHigh birth numbers Good survival of youngPoor survival of young Density-dependentDensity independent ie. Humansie. cockroaches

26.  N/  t = B-D N = population size t = time Change in Population Size Change in population size during time interval Births during time interval Deaths during time interval = -

27. Zero population growth : B = D Exponential population growth : ideal conditions, population grows rapidly

29. Unlimited resources are rare Logistic model : incorporates carrying capacity (K) K = maximum stable population which can be sustained by environment dN/dt = r max ((K-N)/K) S-shaped curve

30. Laboratory Populations

31. Factors that limit population growth: Density-Dependent factors : population matters i.e. Predation, disease, competition, territoriality, waste accumulation, physiological factors Density-Independent factors : population not a factor i.e. Natural disasters: fire, flood, weather

32. Populations fluctuate due to biotic and abiotic factors 1975-1980: peak in wolf numbers 1995: harsh winter weather (deep snow)

33. What do you notice about the population cycles of the showshoe hare and lynx?

34. Boom-and-bust cycles Predator-prey interactions Eg. lynx and snowshoe hare on 10-year cycle

35. Introduced Species Non-native species transplanted populations grow exponentially in new area out-compete native species loss of natural controls lack of predators, parasites, competitors reduce diversity Ex. African honeybee gypsy moth water hyacinth zebra mussel purple loosestrife kudzu gypsy moth

36. Human Population Growth 2 configurations for a stable human population (zero population growth): A.High birth / high death B.Low birth / low death Demographic transition : occurs when population goes from A  B

37. Population Growth Rates Age Structure – the relative number of individuals of each age Used to predict a populations growth trends and bring to light social conditions such as war, immigration, emigration, poor health care, etc. What does the data imply about population growth in these countries?

38. Global Carrying Capacity UN predicts: 7.8 to 10.8 billion people by the year 2050 2012 = 7 billion Estimated carrying capacity = 10-15 billion? Ecological footprint : total land + water area needed for all the resources a person consumes in a pop. 1.7 hectares (ha)/person is sustainable U.S.: 10 ha/person  over K?? Limitations? Consequences? Solutions?

40. Human Population Growth 1650  500 million What factors have contributed to this exponential growth pattern? 1650  500 million Industrial Revolution Significant advances in medicine through science and technology 2005  6 billion adding 82 million/year Population of… China: 1.3 billion India: 1.1 billion

41. Map of ecological footprint of countries in the world (proportional sizes shown)

42. Concept Check Questions 1.Define population. 2.What are the three types of dispersion? 3.What 4 things affect population size and density? 4.This relies on kin selection and reduces individual fitness but increases fitness of recipient. 5.This is the loss of response to stimulus