Population-ecology-graph-worksheet Rennel 646u5n

Name: Rennel Burgos

Date: 07/16/2016

Population Ecology Graph Worksheet Directions: Look at the graphs below and answer the following questions. Graphs 1 - Exponential Growth and Carrying Capacity

1. Which of the two curves exhibits exponential growth? The one that looks like a J curve, colored yellow. 2. Which of the two curves exhibits a carrying capacity? The S curve or the logistic growth, colored green. 3. What is the carrying capacity of this graph? 1000 4. In what generation does this population reach its carrying capacity? Between 24 and 26. Graph 2

1. For what type of organism is the carrying capacity shown? The organism Deer. 2.

3. Give one possible reason why the population decreased in 1990 after it had reached its carrying capacity. Competition in resources had increased and caused a decline in the deer population. 3. Give one hypothesis to explain why the population exceeded its carrying capacity in 1992. Since the population in deer increased it means the competition in resources was minimum and that the number in predators was less causing the deer population to rise again. 4. Why did the population decrease in 1994 after it exceeded the carrying capacity? Normally there would be a number of species or organism that the environment carrying capacity can withhold and their fore causing changes such as population decrease. In this occasion there would be little resources for a large number in deer population causing it to decline once again. Graph 3- Survivor Graphs Graph 3 shows 4 different growth curves- A, B, C & D.

Curve A shows a white woman’s life expectancy in the USA. Curve B shows an Indian woman’s life expectancy in India. Curve C shows fish’s life which has an equal chance of dying at any age. Curve D shows an oyster’s life in which there are many young but few survive to adulthood. 1. Who has a better chance of surviving infancy - Indian or American women? Women in the USA, American women. 2. At what age are most oysters dead? they are mostly dead before the age of 20 years. 3. At what age are most fish dead? They dead before 60 years. 4. Look at Curve A. Notice that it levels off between the ages of 20-40. What does this mean? It means that the percentage in survivors remain the same and that there are no new individuals. 5. Which has a longer life expectancy - fish or oysters? fish have a longer life expectancy.

Graph 4 - Competition Curve Graph 4 shows the growth of 2 species of bacteria grown on the same petri dish. It also shows their growth rate when grown separately.

1. Which of the 2 types of bacteria will soon die? Why? P. Caudatum will soon die. 2. Which of the 2 bacteria strains is better adapted for competition? P. Aurelia. 3. How is the growth rate for P. caudatum different when it is grown alone? In this occasion the both bacteria are grown in the same petri dish and if bacteria P. Caudatum is grown alone it will have more resources and less competition for it to survive longer. 4. What happens to the growth rate of P. aurelia around day 12? Every environment has its carrying capacity, in this case probably resources are startng to become limited or less and bacteria P. Aurelia is reaching its carrying capacity in day 12. Graph 5 – Predator-Prey Graph Isle Royale National Park on a remote island was established in 1940, and designated a wilderness area in 1976. The only mode of transportation available is by boat or seaplane. Moose first arrived at Isle Royale around 1900. The moose population tends to increase in years with mild winters, early spring green-up, abundant winter forage, low wolf numbers and low levels of tick infestation. Wolves first arrived at the island on an ice bridge from Canada in 1940. Disease has also influenced the wolf population. Between 1980 and 1982, the wolf population declined from 50 to 14, due to canine parvovirus.

1. What is the greatest moose population? What year did that occur? What was the wolf population when the moose population the greatest? According to the graph above the greatest population of moose was in the year 1995 with a total of 2500 moose; while the population for the wolf was 15. 2. What would happen to the wolf population if the moose population decreases? If the moose population decreased it would cause the wolf population to decrease as well due to the lack of food and limited resources. 4. What would happen to the moose population if the wolves were removed from Isle Royale? The moose population would increase in large numbers but resources would eventually become less or limited because of competition. 5. Describe the pattern between the wolf (predator) population in relation to the moose (prey) population. The pattern used to describe the wolf and moose population is the boom and bust curve. The boom curve is in a constant change of rise and decline of the population of the wolf, while the bust curve has a rise and decline within a time frame but is not in a constant change. 5. Identify a factor, other than moose population, that has influenced the wolf population in Isle Royale. Disease would be a factor. 6. Identify two factors, other than the wolf population, that may influence the moose population. Since deer is an animal that is hunted in other areas, hunting would be a factor as well as disease. 7. Isle Royale has been undeclared as a national park and has been purchased by a large resort. Describe one positive and one negative impact on the Isle Royale ecosystem. Now a days most places are kept as reserves and are considered protected areas for survival of an ecosystem or its species living in it, so a positive impact would be to keep the Isle Royale as a protected area or reserve. A negative impact would be the destruction of ecosystems or land for man uses such as industrialization and tourism impacts. 8. Are predator-prey relationships density-dependent or density-independent limiting factors? Explain. Most likely it would be density- dependent since the number of prey and the amount of predators depend on each other, in order to maintain the number of species in a stable or moderate condition for the survival of both species rather than reaching its carrying capacity and cause a large decrease in numbers.