UNIT 3 Environmental Science REVISION

Australia possesses a unique assemblage of mammal species, of which over 80% are endemic. This high level of endemism is a result of Australia's

• Distance from other countries.

• High ecosystem biodiversity

• Long period of isolation from other land masses

• Large number of marsupials

Western Victorian Volcanic plains is an example of a Biodiversity hotspot. This is because:

• It hosts the largest population of Eastern Barred Bandicoots on the mainland and they are under threat from human activity.

• It is the only area in Victoria with over 400 volcanoes

• The area has a low animal diversity and many are endemic to the area.

• The area has a high ecosystem diversity and many of these are under threat from human activity.

Species that are endemic to one particular area are a priority for conservation measures mainly because:

• The species already is experiencing a restricted habitat suggesting the species is at greater risk of extinction.

• The species provides social benefits to visitors to the area.

• There is only one population of the species remaining in the wild

• Populations in different areas have become separated and exist only on patches of remaining vegetation

Which statement is correct?

• Site 1 has a higher species richness but lower species diversity than Site 2.

• Site 2 has a lower species richness and lower species diversity than Site 1

• Site 1 has a higher species diversity and species abundance the Site 2

• Site 2 has a lower species richness and lower relative species abundance than Site 1.

Globally we are witnessing a decline in wild bees, honeybees and hover flies, caused by the destruction of habitats, increase in land use for agriculture and use of pesticides. This will greatly impact the food security because:

• A loss of pollinators will result in a loss of crop supplies

• Habitat destruction will impact areas for agricultural pursuits

• The use of pesticides always leads to biomagnification

• Pollinators and crops are example of commensalism.

As a consequence of the habitat destruction of tropical forests, the reduced numbers of migratory birds and the regeneration of temperate plant species has been found to be connected. This is most likely because:

• The temperate habitat no longer supports the nesting sites of birds.

• The temperate plant species rely on the birds to disperse seeds as they migrate.

• The tropical forests and temperate forests have the same species.

• The birds have not been able to adapt to the loss of plant species and therefore no longer travel here.

Having a greater genetic diversity within a population will support a species to survive:

• When their habitat is removed by deforestation.

• When the population is impacted by disease and climate change.

• When an exotic species out-competes the population for a resource.

• When a predator reduces the population numbers.

Habitat size and shape can greatly impact the conservation value of an area and impact the biodiversity within it. The size and shape of habitat fragment that is most likely to be impacted by the surrounding environments is:

• Small and circular

• Large and circular.

• Small and elongated.

• Large and elongated.

The Swift Parrot migrates to the mainland during summer and returns to Tasmania during nesting season. Unfortunately, the Sugar Glider, which was introduced to Tasmania in the early 1800s, preys on the eggs and chicks of the Swift Parrot and has been impacting the successful breeding of this critically endangered species. Which statement is most correct?

• The Swift Parrot is likely to become extinct within 5 years.

• The Swift Parrot is endemic to mainland Australia.

• The Sugar Glider is endemic to Tasmania and should be protected.

• The Sugar Glider is an exotic species in Tasmania

Elephants in Africa have recently shown evidence of evolution driven by poaching. More and more elephants are maturing without tusks. This is an example of:

• Natural selection at work to prevent the demise of the elephant population.

• Natural selection at work due to a selection pressure.

• Natural selection at work to ensure the poachers no longer have a target.

• Natural selection at work due to low genetic diversity.