Unit 3 Topic 1 Recap

A group of the same species that live in a particular area at the same time is know as

• A community

• A population

• An ecosystem

• A niche

Define an ecosystem.

You are designing an experiment where you want to measure the biodiversity of a desert in which the only plant is spinifex. The best measure of biodiversity in this case is

• Species richness

• Relative species abundance

• Percentage cover

• Simpson's Diversity Index

Answer explanation

Because you only have 1 species (spinifex), the best measure is percentage cover. If you had more than 1 species present (also cactus, trees etc) then you would use other measures

What is the difference between species richness and species evenness?

Calculate species richness for the given data set.

Describe the benefit of using Simpson's diversity index over Species Richness as a measure of biodiversity.

Use the data set to calculate Simpson's Diversity Index (SDI).

Two different ecosystems were sampled and the SDI calculated. Ecosystem 1 SDI = 0.9 whereas Ecosystem 2 SDI = 0.3. Infer which ecosystem has greater biodiversity.

• Ecosystem 1 has greater biodiversity because 0.9 < 0.3

• Ecosystem 1 has greater biodiversity because 0.9 > 0.3

• Ecosystem 2 has greater biodiversity because 0.9 < 0.3

• Ecosystem 2 has greater biodiversity because 0.9 > 0.3

What is the commonly accepted threshold for statistical significant in a t-test?

• 0.1

• 0.5

• 0.05

• 0.005

Draw your favourite animal