Biodiversity within a community

Question 1

Suggest how this student would obtain data to give a more precise value for the index of diversity of this habitat.

Answer 1

1. Obtain larger sample and find the mean
2. Random number generator

Question 2

The ecologists captured insects from a number of sites on the island. Suggest how they decided where to take their samples.

Answer 2

1. Draw grid over (map of) area;
2. Select squares / coordinates at random.

Question 3

Suggest one way in which the method used by the ecologists might have caused the increase in their estimates of the size of the insect population.

Answer 3

1. Scientists removed large numbers of insects from same area
2. Affecting ratio of marked to unmarked.

Question 4

What two measurements are needed to calculate an index of diversity?

Answer 4

1. Number of individuals of each species;
2. Total number of individuals / number of species;

Question 5

Explain how a very high diversity of bird species has developed in the Amazonian forest.

Answer 5

1. No interbreeding
2. Mutation;
3. Different selection pressures / different foods / niches / habitats;
4. Adapted organisms survive and breed
5. Increase in allele frequency