I posted this question earlier tonight, since the \"expert\" help -trivium- said
ID: 105469 • Letter: I
Question
I posted this question earlier tonight, since the "expert" help -trivium- said it was too ambiguous and couldnt be answered. I did some research and came up on the answer myself. Thank you for nothing useless expert. Glad I spend 14.95 for this site. So here is the answer to my own question posted below:
Some 40,000,000 years from now the volcanic Erebor Archipelago will form west of the Australian subcontinent (the nearest major landmass). After reading Section 20.4 in your text, contemplate the following geographical data, and answer the questions below:
Island Distance from Australia (km) Size (km2)
North Panem 3502 1544
South Panem 3523 95
Snow 955 1540
Mellark 950 99
Everdeen 789 444
Haymitch 1828 699
A. Based on the Equilibrium Theory of Island Biogeography (MacArthur and Wilson), predict the following and explain your choice (6 points):
First let me explain what this Theory is: The equlibrium theory of island biogeography states that in order to predict species richness it has to be determined based on isand size (area) and distance (isolation) from the main land. This Theory does not try to predict composition or abundance. It also considers species richness to be in dynamic equilibrium between immagration and extinction. extinction and colonization rates are affected by island size and distance. Larger ilsands have more species and closer islands have more species.
Island(s) with highest colonization rates: According to the theory the island that is closest and is the largest wil have the highest colonization initialy. This would be snow island at a distance of 955km. While it is true Mellark is closer at 950 km, Snow is 1540 km in size compared to the small size of 99km of Mellark
Island(s) with lowest colonization rates: Using this same theory, the smallest lsland and furthest away from Australia should have the lowest colonization which in this case would be South Panem. Furthest at 3523km and smallest at 95km.
Island(s) with highest extinction rates: Mellark is mmost likely going to experience the highest levels of extinction according to the theory. The islands that are the cloest and the smallest experience the highest extinction and turn over rate. Mellark is the closest at 950km and smallest at 99km.
Island(s) with lowest extinction rates: North Panem, according to this same theory wil experience the lowest extinction rate. The theory states closer and smaller equals higher rates, therefor the farther and larger should experience the lowest extinction rate. Notrth Panem fits this description of a distance of 3502km and size of 1544km.
Island(s) with highest equilibrium species richness: When observing species richness, 3 main things are involved: Immigration, extinction, and evolution. Snow in theory should have the highest species richness. The island is close to Australia, providing great immagration, low extinction, and a vast habitat diversity for evolution.
Island(s) with lowest equilibrium species richness: South Panem in theory should have the lowest species richness because a lot of species would not be able to survive the trip to the island being so far away, and those that do survive will not be met with a lot of habitat diversity. So if they do make it that far, they better hope the environment is suitable to live in.
B. This model does not always predict the number of species on an island. Examples of one factor influencing the number of species on an island that is not incorporated in this model include finches in the Galápagos Islands and honeycreepers and Drosophila in the Hawaiian Islands. What factor is this? (10 points)
The two big things that arent taken into account are adaptations and evolution. A new species may evolve on the island that might not evolve on the main land due to some environmental factor, or some other factor. Also, this only takes into account how far it is from Australia. An Island far away, like North Panem which contains a large area of land might be cose to another large body of mainand with species to inhabit it. It may not have a rich species from australia, but that doesn't mean it will go inhabited. Also, you have to consider other factors like humans introducing species to far away islands.
- Please feel free to use my answers, again no thanks to Trivium's "expert" help.
Explanation / Answer
A. Based on the Equilibrium Theory of Island Biogeography (MacArthur and Wilson), predict the following and explain your choice (6 points):
Island(s) with highest colonization rates:
Island(s) with lowest colonization rates:
Island(s) with highest extinction rates:
Island(s) with lowest extinction rates:
Island(s) with highest equilibrium species richness:
Island(s) with lowest equilibrium species richness:
B. This model does not always predict the number of species on an island. Examples of one factor influencing the number of species on an island that is not incorporated in this model include finches in the Galápagos Islands and honeycreepers and Drosophila in the Hawaiian Islands. What factor is this? (10 points)