Ecology Mini-Exam #1 Name:______
1. Define the following terms
Fact: That which has actual existence, like an idea.
Truth: That which is consistent with fact and reality
Reality: That which has objective existence.
2. List Darwin’s 5 observations
a) There is variation between organisms.
b) Some of that variation is heritable.
c) Some forms of variation are better than others.
d) Populations tend to grow exponentially.
e) Populations can not grow exponentially for very long.
3. Stabilising selection occurs when A) the middle of the phenotype distribution is selected against, while the extremes are selected for. B) the extremes are selected against and the middle is selected for. C) one extreme is selected for and the other extreme is selected against. D) one sex is selected for while the other sex is selected against.
4. In order for speciation to occur, there must be (circle all that apply) A) some limit to gene flow. B) genetic drift. C) stabilizing selection. D) directional selection. E) geographic isolation. F) reproductive isolation.
5. T / F For the most part, organisms living today are perfectly adapted to their environments.
6. T / F Evolution results in the perfection of species, with the ultimate result being the production of human-like forms.
7. T / F Evolutionary change is slow and gradual.
8. Evolution can be defined as A) the gradual perfection of species. B) the change of monkeys into men, or wolves into dogs. C) change in genotype frequencies over time. D) change in allele frequencies over time. E) change in phenotypes over time.
9. What are the assumptions of Hardy-Weinberg equilibrium
a. The population is closed.
b. Reproduction is panmictic.
c. All genotypes have equal reproductive success.
d. All genotypes have equal survival.
General Ecology Mini-Exam #2 Name:______
1. What is a population? A) a group of organisms reproductively isolated from other such organisms. B) a group of conspecifics inhabiting a given place at a specific time. C) a group of individuals working together for the common good. D) any group of organisms that can interbreed.
2. T / F The flying squirrels in Mexico are part of the same population as flying squirrels in the U.S. and Canada.
3. Imagine you have a population of mice in a barn. You set out 200 live traps and catch 10 mice on the first night. You mark each mouse with an ear tag, and release it at the point of capture. You set out 200 traps on the next night. The next morning you discover 20 mice in your traps. Of these 20 mice, 5 were ear-tagged. How many mice are in the population? (note: N = n1n2/m2).
N = (10*20)/5 = 40
The barn is 50m long and 10m wide. You did some calculations, and discovered that on average, the 5 marked mice moved 5m from the first time they were captured to the second time they were captured. Now, what is the population density? (Recall: the area of a circle = pr2 where p = 3.14).
D = N/A = 40 / [(50*10) + 2*5*50 + 2*5*10 + p*5^2] = 40/[(500) + 500 + 100 + 78.5]
= 40 / 1178.5 = 0.0339 mice per square meter.
Consider our model for population growth: DN / Dt = rN ( 1 – N / K). What happens to population size under each of the following conditions?
N < K: increase / decrease / stay the same
N = K: increase / decrease / stay the same
N > K: increase / decrease / stay the same
4. If a growing population ‘overshoots’ the carrying capacity in a significant way, what happens? A) the population will continue to grow exponentially. B) the population will oscillate around K, and ultimately settle down to K. C) the oscillations around K will persist for a long time, depending on the magnitude of r. D) if r is very large, the population will first exceed K, and then crash to extinction. E) B through D are correct. F) A and D are correct.
5. List 2 morally and ethically acceptable ways in which we can control human population growth:1) Increase the age of first reproduction. 2) Increase the amount of time between children. How to do this? Get women onto career tracks, with the effect that they develop their professions before starting families.
General Ecology Mini-Exam
1. T / F Can the logistic growth model produce patterns of chaotic population growth?
2. What is meant by a stable age distribution? A) all populations grow at the same rate. B) the age classes are all the same size. C) all age classes are growing at the same rate. D) population growth is constant.
3. Which of the following are not assumptions of the logistic growth model? A) birth rates are equal for all age classes. B) death rates are equal for all age classes. C) all individuals have equal fecundity. D) survivorship is equal across all individuals. These are all assumptions for Logistic growth.
4.
Consider the model below. Define the terms of in the equation.
Bf(t) Births to females at time T
g(t) The initial cohort
l(x,t) Survivorship to age X at time T
m(x,t) Fecundity for females aged X at time T
5. What is the advantage of the renewal equation over the logistic growth model?
It allows us to model age structured population growth, and growth for populations with age specific fecundity and survivorship.
6. What is the goal of all life history strategies? A) maximize survivorship. B) maximize the number of matings. C) maximize inclusive fitness. D) maximize physical fitness.
7. T / F Parental care and fecundity are inversely related.
8. T / F offspring that receive little parental care generally have a low probability of survival.
9. How is resource availability related to parental energy investment? A) as available resources increase, parental investment in offspring increases. B) as available resources increase, parental investment in offspring decreases. C) as available resources increase, parental investment in individual offspring decreases, but overall investment in all offspring increases.
10. Compare and contrast the life histories of Panamint kangaroo rats and Pinyon mice.
They are the same in that both species try to maximize inclusive fitness. They differ in that Pinyon mice have short lives, produce large litters, exhibit little parental care, and reproduce at every opportunity. K Rats on the other hand are long lived, attempt to avoid predation, produce small litters and exhibit a great deal of parental care. Also, K rats will delay reproduction until conditions are more suitable.
11. T / F Mate choice is generally practiced by the male.
12. T / F Female parental investment increases faster with each additional offspring than does male parental investment.
13. The optimal number of offspring for females is greater than the optimal number of offspring for males. False
14. What is sexual bimaturism? The 2 sexes mature at different rates.
15. Under what conditions does sexual bimaturism occur? When there is strong competition for access to mates.
16. What is the parent-offspring conflict? Conflict between strategies for parents and offspring. Parents try to maximize their own inclusive fitness while offspring attempts to maximize its fitness. What is best for the parent is not necessarily what is best for the offspring’s direct fitness.
17. Define the following terms:
a. Monogamy One male and one female
b. Polyandry One female and many males
c. Polygyny One male and many females
d. Promiscuity The most common mating system for living organisms – each sex has many mates.
18. Which is the most common mating system in living organisms? A) monogamy. B) polyandry. C) polygyny. D) promiscuity.
19. Which of the following environmental conditions favor monogamy? A) altricial young. B) a local or seasonal superabundance of food. C) an even distribution of resources. D) female territories nested within male territories. E) a great deal of energy required to rear the young. F) Sexual bimaturism.
20. In a potentially polygamous system, is the female generally off better off with the monogamous male or the polygynous male? A) monogamous male. B) polygynous male.
21. T / F Females generally have higher reproductive variance than males.
22. T / F Males generally have a higher mean number of offspring than do females.
Ecology Mini Exam: Competition
1. T / F In order for competition to occur, resources must be limiting.
2. Intraspecific competition refers to competition within ______species while interspecific competition refers to competition _between______species.
3. State the competitive exclusion principle as formulated by Gause: No 2 species can occupy the same niche at the same time.
4. What is our working definition of the niche? Where an organism lives and what is does.
5. What happened when Gause added crushed glass to the bottom of his petri dish? Both species of paramecium were able to persist.
6. Consider the figure below on the left. Label the A) Resource Utilization Curve, B) the Resource Availability Curve, C) a curve representing the niche, and D) a portion of the figure representing potential competition.
7. Explain the significance of the graph on the right, above.
When resources are negatively correlated it is possible to have overlap on each individual axis, but no competition overall.