3.2

Question 1

Define ecological succession

Answer 1

Transition in species composition over time.

Question 2

Define primary succession and give an example.

Answer 2

An almost lifeless area with no soil first gets bacteria, moss, and lichen, which create soil, then grasses and shrubs begin to grow, often taller plants begin to grow next and change the area into a forest. An example would be a volcano erupting with lava flow.

Question 3

Define secondary succession and give an example.

Answer 3

An existing community is cleared, but the base soil is still intact. It can cause more biodiversity if the entire community of plants and animals is not destroyed. An example would be logging a wooded area.

Question 4

Define pioneer species

Answer 4

The first living things to come to an area devoid of anything but rock.

Question 5

Define seral stages

Answer 5

The stage where more, different living things come to an area already inhabited by the pioneer species.

Question 6

Define climax community

Answer 6

The final stage in primary succession, a community full of plants and animals.

Question 7

Define species richness

Answer 7

The amount of species in an area.

Question 8

Define ecological diversity

Answer 8

The variety of communities, ecosystems, and habitats in an area.

Question 8

Define genetic diversity

Answer 8

The amount of different DNA present in a population.

Question 9

Define keystone species

Answer 9

A species that is vital to an ecosystem

Question 10

How do keystone and invasive species affect biodiversity?

Answer 10

Keystone species preserve the biodiversity of an ecosystem, invasive species can destroy it.

Question 10

Define invasive species

Answer 10

A species that invades a different area where it has no natural predators and it can take over the area.

Question 11

How are primary succession and secondary succession different?

Answer 11

Primary succession is the slow process of bare rock becoming a thriving ecosystem, secondary succession can take less time and usually has soil already.

Question 12

Find the Shannon-Weiser index and evenness of a community with 5 species, with amounts in each species of 25, 28, 39, 32, and 14.
Compare this community to one with a richness of 6 species that have 19, 15, 51, 10, 4, and 11.

Answer 12

1st community:
H = 1.56
E = 0.97
2nd community:
H = 1.52
E = 0.85
The first community has less species than the second, but the amounts are more even, the second community has more species, but the species are less even.