AUSTRALIAN BIOTA
The very large southern landmass, Gondwana, persisted for some time, giving rise to
an array of species that spread across it. When Gondwana broke up, it did so in stages
but eventually the Australian continent was isolated from Antarctica and South
America.
The available evidence suggests that, as Gondwana was breaking up, a number of
global climatic changes were also occurring. These changes in environmental
conditions impacted on Australian ecosystems and are reflected in the fossil record.
As the biotic and abiotic features of ecosystems were altered, those organisms best
adapted to these changes survived and passed on their genetic information to their
offspring.
The contribution of paleontology and the study of past environments are important to
our understanding of how our present actions may affect our environment and the
distribution of flora and fauna in the future.
Identify and describe evidence that supports the assertion that Australia was once
part of a landmass called Gondwana, including:
- matching continental margins
- position of mid-ocean ridges
- spreading zones between continental plates
- fossils in common on Gondwanan continents including Glossopteris and
Gangomopteris flora and marsupials
- similarities between present day organisms on Gondwanan continents
Things to consider:
- What does identify and describe mean?
- What does assertion mean?
- Underline key words
- Be succinct
There is a mountain of evidence which supports the theory that Australia was once
part of a landmass called Gondwana. The following evidence shows this.
 Matching continental margins: Geologists have discovered through rock strata
analysis that Southern Australia is a perfect boundary match with that of
Antarctica, and between the west coast of Africa and the east coast of South
America.
 Mid-ocean ridges: The study of mid ocean ridges has suggested that when
plates move mantle material wells up and creates new ocean floor. Scientists
have then deduced the further away from the ridge the older the rock is. This
evidence suggests that Australia was once part of the landmass called
Gondwana.
 Spreading zones between continental plates: These are areas of new ocean
floor forming between continental plates. Analysis of the ocean floor and
spreading zones has lead to the assertion that Australia was once part of the
Gondwanan super continent.
 Fossils in common on Gondwanan continents including Glossopteris and
Gangomopteris flora and marsupials: These plant fossils have been found in
rocks of the same age in Africa, Australia, India, South America, Antarctica
and New Zealand. This evidence supports the assertion that Australia was
once part of the super continent known as Gondwana.
 Similarities between present day organisms on Gondwanan continents: There
are many similarities between present day organisms and their Gondwanan
continents. For example the Rhea, Ostrich, Emu, Cassowary and Kiwis are all
examples of present day organisms which show extremely similar
characteristics. These organisms also suggest by their geographical positioning
that Australia was once part of the landmass called Gondwana.
Discuss current research into the evolutionary relationships between extinct species,
including megafauna and extant Australian species
Things to consider:
- What does discuss mean?
- Underline key words.
- Use scientific terminology, be succinct
Evolutionary relationship refers to how closely one organism is related to another.
From this we can draw on how closely related extinct species such as megafauna are
to current Australian species. Firstly megafauna as the name suggests are large
animals. Current living megafauna include elephants and whales. However over the
last 50000 years megafauna have becomes extinct. Extinction was more than likely
due to a number of factors including climatic change and human expansion.
Evolutionary relationships can be shown between megafauna and current Australian
species. For example if we compare the diprotodon and the common wombat we can
identify many structural similarities. Structural similarities include skull structure,
body covering, length and structure of limbs, ears and snout are all similarities
between that of the wombat and the diprotodon. This example illustrates the
evolutionary relationships between extinct Australian megafauna and current
Australian species. (Other evolutionary relationships include; giant kangaroo vs
kangaroo, giant echidna vs echidna and Genyornis vs the emu to name a few.)
VS
Solve problems to identify the positions of mid-ocean ridges and spreading zones that infer
a moving Australian continent
Things to consider:
- What does solve mean?
- What does identify mean?
- Understand the question so that the answer is correctly and accurately
represented
AIM:
To investigate and solve problems to identify the position of mid-ocean ridges and
spreading zones that infers a moving Australian continent.
METHOD:
1. Using secondary sources identify the tectonic plates and the positions of midocean ridges, trenches and spreading zones. You may wish to draw your
answer.
DISCUSSION QUESTIONS:
1. Explain how the theory of plate tectonics has changed our ideas about the
surface of the Earth.
2. Which tectonic plate is entirely oceanic?
3. It has been suggested that the Atlantic Ocean is expanding and the Pacific
Ocean shrinking. What evidence supports this idea?
4. If the sea floor spreads from the mid-Atlantic ridge at the rate of 2.5cm per
year, how many kilometers of new crust will be laid down over one million
years?
5. The city of San Francisco has experienced Earth tremors and earthquakes over
the last 100 years. What is the reason for this?
6. The Earth’s crust is recycled over time. Explain how this happens.
7. On which tectonic plate is the continent of Australia.
8. It has been said that Australia is drifting northwards at about 6cm a year. What
technological advances have helped us to measure this?
9. Explain, with examples, how technological advances have increased our
understanding of plate tectonics.
Identify data sources, gather, process and analyse information from secondary
sources and use available evidence to illustrate the changing ideas of scientists in the
last 200 years about individual species such as the platypus as new information and
technologies became available
Things to consider:
- This is a secondary source question, so it’s to your discretion as to how and
where you will find your information.
- What does analyse and process mean?
- Use scientific terminology
AIM:
To look at the changing ideas of scientists in the last 200 years about the platypus.
METHOD:
1. Research the platypus, identifying data sources and collecting information to
write a report as outlined by the discussion questions.
DISCUSSION QUESTIONS:
For the platypus, produce an illustrated report that includes the following:
 An outline of the changes we believe have occurred over time.
 A description of the evidence for these changes (include both geological and
biological evidence.)
 A discussion of the ways our ideas have changed over the past 200 years.
What new information has become available? What new technologies and/or
processes have allowed us to find out more?
Discuss examples of variation between members of a species
Things to consider:
- What does discuss mean?
- What examples are you going to use?
- What is variation?
Variation refers to a slight difference within a species. For example you are not
identical to anyone in the classroom. This represents variation within the human
species. Variation may occur for various reasons such as competition for resources or
the organism’s environment.
Examples of variation between members of a species in Australia include the white –
naped honeyeater (Melithreptus lunatus). This bird is distributed throughout
Australia. However there is distinct variation between populations of the species. For
example the eastern Australian white – naped honeyeater has a short beak and an
orange patch around its eye. Compared to that of the western Australian white –
naped honeyeater which has a larger beak and a white or green patch around its eye.
This example shows variation within a species due largely to geographical isolation
and more than likely the honeyeater’s environment.
EASTERN HONEYEATER
WESTERN HONEYEATER
NOTE THE DIFFERENCE. ORANGE VS WHITE PATCH AROUND THE
EYE.
Identify the relationship between variation within a species and the chances of
survival of species when environmental change occurs
Things to consider:
- What does identify mean?
- Underline key words and make sure you understand what these words mean
- Be succinct
In order for a species to survive environmental change there must be variation within
that species. If there is no variation within a species that species is susceptible to
many factors which in turn could eliminate that species. For example a deadly
bacteria sweeps through a population if there is no variation in that species the species
will die out. Therefore all species need to ensure there is variation from one
generation to the next. This ensures that if there is an environmental change the
species will have some chance of survival.
Identify and describe evidence of changing environments in Australia over millions of
years
Things to consider:
- What does identify and describe mean?
- What type of evidence will we be looking for?
- Use scientific terminology
When Australia was still joined to Antarctica (65 million years ago) the climate was
cool, wet and the land was covered by temperant rainforest. The next 20 million years
saw Australia gradually breakaway from Antarctica and begin to drift northwards.
While Antarctica became cooler, Australia was becoming increasingly warmer due to
the northward drifting and the Australian rainforest shrank while other types of
vegetation increased. As Australia continually drifted northwards, past the Tropic of
Capricorn, the climate in the north of Australia became very tropical. To this day
Australia continues to move north at about 6cm per year. There are many different
environments including the tropical north east, the arid centre and the temperate east
and western coasts. Therefore Australia’s environment has changed over millions of
years.
Identify areas within Australia that experience significant variations in temperature
and water availability
Things to consider:
- What does identify mean?
- How will you represent your information?
The diagram below illustrates the significant variations in temperature. Note the
key.
The diagram below illustrates the significant variations in water availability.
Note the key.
Identify changes in the distribution of Australian species, as rainforests contracted
and sclerophyll communities and grasslands spread, as indicated by fossil evidence
Things to consider:
- What does identify mean?
- Underline key words
- Understand what the question is asking before you answer
As Australia’s environment changed so did the distribution of organisms. Organisms
which could adapt to the warmer and drier conditions flourished in the new
ecosystems while those organisms who struggled to adapt either became extinct or
found little environmental pockets where they could survive. This is evident in such
fossil sights such as Riversleigh and Naracoorte. Riversleigh fossils show that the
Australian climate must have changed to warmer and drier conditions. Naracoorte
fossils suggest that lakes dried up and forests became open woodland. This fossil
evidence therefore suggests that the distribution of Australian species changed
according to the changing environment.
The following table indicates successful species which diversified in Australia’s
changing environment.
PLANTS
ANIMALS
 Acacias (950 species) and
 When Australia became a separate
Eucalypts (800 species) are highly
continent it contained three types
adapted Australian vegetation.
of mammals: placentals,
marsupials and monotremes.
 Acacias adapted to hot arid
conditions. Found almost
 The most successful group were
anywhere including; tropical
the marsupials.
rainforests, woodlands, arid areas,
 Marsupials adapted to the warmer
coastal heaths and sand dunes.
drier conditions to occupy many
 Eucalypts adapted to Australian
ecosystems.
hot arid conditions. Found mainly
 Today there are 141 different
in forests and woodlands.
species of marsupials.
Discuss current theories that provide a model to account for these changes
Things to consider:
- What does discuss mean?
- Underline key words
- Be succinct
Current theories that provide a model to account for these changes are climate change
and human impact.
CLIMATE CHANGE: As Australia moved northwards the mean temperature rose
and the availability of water declined. This lead to the reduction of rainforests and the
beginnings of woodlands and open grass plains. Another key factor which supports
this theory is the radiation of Australian marsupials and plant species such as
eucalypts. These organisms also support the theory of climate change based on their
distribution and abundance.
HUMAN IMPACT: Human impact is one theory behind the changes experienced on
Australia. Firstly the Aborigines and their hunting practices (using fire) may have lead
to the extinction of Australian megafauna.
The arrival of Europeans also changed local ecosystems due to their agricultural
practices, degradation of woodlands/forests and the introduction of foreign species.
These factors illustrate that human impact could be one theory that that influences
Australia’s environment.
Discuss Darwin’s observations of Australian flora and fauna and relate these to his
theory of evolution
Things to consider:
- What does Discuss mean?
- Who is Darwin? What is evolution?
Darwin visited Australia around 1836. He visited NSW, Tasmania and WA, in a quest
to understand how and why organisms evolve. He took notes of Australia’s native
flora and fauna to support his theory of natural selection. When in Australia Darwin
noticed the following: crows like English Jackdaws, a rat kangaroo (potoroo) which
he compared to a European rabbit both in size and behaviour and platypuses similar to
that of water rats in Europe according to their behaviour. Darwin also made
comparisons between the flora in Australia and Europe. These are the features
(adaptations) he noticed of Australian flora: trees leaves hang vertically compared to
Europe which hang mainly horizontally, leaves are light green, generally thin and
have a relatively small surface area compared to that of Europe which are glossy and
have a larger surface area and the bark of the trees is lighter in colour compared to
that of the trees in Europe.
Darwin’s observations of Australian native flora and fauna relates to his theory of
evolution because:
 The adaptations of the trees are suited to its environment, therefore supporting
the theory of natural selection. (Survival of the fittest)
 The adaptations of the native fauna such as the potoroo, crows and platypuses
as a generalisations allows them to survive within Australia’s environment
therefore supporting Darwin’s theory of natural selection.
http://www.youtube.com/watch?v=1Gnxy8p3TBs
Gather, process and analyse information from secondary sources to develop a
timeline that identifies key events in the formation of Australia as an island continent
from its origins as part of Gondwana
AIM:
To draw up a timeline and identify key events in the formation of Australia from the
time of Gondwana.
METHOD:
1. Access secondary sources to construct a timeline, identifying the formation of
Australia as an island continent.
2. Once you have drawn your timeline research/try to find a flow diagram/flash of
Australia actually breaking away from Gondwana. Draw/print this diagram out.
RESULTS:
Timeline and flow diagram/printout placed in this section.
DISCUSSION:
1. Why is evidence of key events important in the development of our understanding
of the evolution of our continent?
2. How do fossils contribute to our understanding of life, both past and present?
RELEVANT WEBSITES
http://www.environment.gov.au/heritage/places/national/dinosaur-stampede/larkquarry/interactives/pangaea.html
http://www.apstas.com/gondwanatimeline.htm#GONDWANA
http://community.boredofstudies.org/16/biology/149733/timeline.html
Gather information from secondary sources to describe some Australian fossils,
where these fossils were found and use available evidence to explain how they
contribute to the development of understanding about the evolution of species in
Australia
AIM:
To identify key fossils and explain how fossil evidence contributes to the
development of understanding about the evolution of species in Australia.
METHOD:
1. You are to research and gather information from the following areas which contain
fantastic fossil evidence which increases our understanding about the evolution of
species in Australia:
* Riversleigh: World heritage fossil site
* The Pilocene wetlands of Bluff Downs
* Murgon: Eocene connection
* Lightning ridge: ancient monotremes
* The Naracoorte megafauna
* Ancient mammal and giant amphibians: Inverloch - San Remo
* The fossil fishes of Gogo
RESULTS:
Research the above areas and state how they increase our understanding about the
evolution of species in Australia.
Perform a first-hand investigation, gather information of named Australian fossil
samples and use available evidence to identify similarities and differences between
current and extinct Australian life forms.
AIM:
To describe a number of named Australian fossils as well as identify similarities and
differences between current and extinct organisms.
METHOD:
1. Observe each of the fossils in the classroom and complete the set of results for
each fossil examined.
RESULTS:
 Make a large labeled sketch of each fossil.
 For each fossil suggest a modern-day representative. Write this next to your
sketch. If unsure write “no modern-day representative.”
 For each fossil list the similarities and differences it has with the modern-day
representative. If you wrote no modern-day representative suggest a reason
why there isn’t one. Record this information next to your sketch.
DISCUSSION QUESTIONS
1. Explain the advantages in an investigation of examining actual fossils rather
than observing fossil photos or diagrams.
2. Outline how the study of extinct and current Australian organisms provides
evidence for evolution.
Present information from secondary sources to discuss the Huxley – Wilberforce
debate on Darwin’s theory of evolution.
AIM:
To discuss the Huxley – Wilberforce debate on Darwin’s theory of evolution.
METHOD:
1. You are to use other resources such as the internet to discuss the Huxley –
Wilberforce debate on Darwin’s theory of evolution. The key word is present
so you must choose how to present your information for example in report
format, using word, using PowerPoint and incorporating pictures to name a
few.
RESULTS:
As stated above in the method.
DISCUSSION:
1. In the debate what theory was Huxley supporting? What theory was
Wilberforce supporting?
2. Why is this debate so well remembered? What was the outcome of this
debate?
3. Present day apes and humans show many similar features. Several million
years ago they shared a common ancestor. Why is it untrue to say that humans
are “descended from apes”?
Perform a first – hand investigation to gather information of examples of variation in
at least two species of living organism
AIM:
To examine variation in two species of living organisms.
METHOD:
1. Examine the various species of plants and animals.
2. Observe each specimen noting certain features such as size, colour and
structure. Record your observations into a results table.
RESULTS:
SPECIES
NAME
FEATURE FEATURE FEATURE FEATURE ADDITIONAL
1
2
3
4
COMMENTS
DISCUSSION:
1. How does variation within a species increase the chance of survival of a
species?
Distinguish between the processes of meiosis and mitosis in terms of the daughter
cells produced.
Things to consider:
- What does distinguish mean?
- Find out the differences between meiosis and mitosis
- What is a daughter cell?
- Be succinct
-
-
-
MITOSIS
Process produces two daughter
cells which are identical to that of
the parent cell
Chromosome numbers in the
daughter cells are same in number
to that of the parent cell.
Chromosomes line up singly
Occurs in all living things
Used for growth, asexual
reproduction and repair.
Daughter cells are somatic (2n)
-
-
-
MEIOSIS
Process produces four daughter
cells which are NOT identical to
that of the parent cell
Chromosome numbers in the
daughter cells are half of the
parents
Chromosomes line up in pairs
Occurs only during sexual
reproduction.
Only in sexual reproduction.
Daughter cells are gametes (n)
Other key words that are beneficial to know now for years 11 and 12 are:
Asexual:
Sexual:
Parthenogenesis:
Fertilisation:
Chromosomes:
Genes:
DNA:
Gametes:
Somatic cell:
Haploid:
Diploid:
Compare and contrast external and internal fertilisation.
Things to consider:
- What does compare mean?
- What does contrast mean?
- Use scientific terminology
- You may use two tables one that shows similarities the other that shows
differences, or both in one.
EXTERNAL FERTILISATION
- Male gametes swim to female
gametes outside the body by
motility
- No copulation (intercourse)
- Male gametes spread over a larger
area therefore there is less chance
of fertilisation
- Large amount of female gametes
produced
- Zygote forms outside of the
female/males body
- Most common in fish, amphibians
and algae
INTERNAL FERTILISATION
- Male gametes swim to the female
gamete within the body
- Copulation occurs (intercourse)
- Male gametes are shed into a
confined space therefore there is a
greater chance of fertilisation
occurring
- Limited amount of female
gametes produced
- Zygote develops within the
females body until developed
- Common on land plants, reptiles,
birds and mammals
Analyse information from secondary sources to tabulate the differences that
distinguish the processes of mitosis and meiosis.
Things to consider:
- Key words = analyse, tabulate, distinguish.
- Ensure you show the differences between meiosis and mitosis
- You may wish to use pictures with your table.
AIM:
To research and tabulate the differences that distinguishes the processes of mitosis
and meiosis.
METHOD:
1. You are to use the internet to identify and distinguish between the processes if
mitosis and meiosis.
2. Construct a table in your workbook to illustrate your answer.
RESULTS:
A table that distinguishes between the processes of mitosis and meiosis.
You may wish to show the two processes using pictures and illustrate how they are
different to one another.
Identify data sources, gather, process and analyse information from secondary
sources and use available evidence to discuss the relative success of internal and
external fertilisation in relation to the colonisation of terrestrial and aquatic
environments
Things to consider:
- What do the following words mean; identify, gather, process, analyse and
discuss?
- Underline key words
- Be succinct
- Understand what your answer may require before you write an answer
AIM:
To examine and compare the different reproductive strategies employed by terrestrial
and aquatic organisms.
METHOD: PART A:
1. Copy and complete the following table.
TYPE OF
DEFINITION
NUMBER
HAZARDS STRATEGIES
FERTILISATION
OF
IN
TO ASSIST
GAMETES PROCESS
PROCESS
PRODUCED
PART B:
1. Research the reproductive strategies of one aquatic and one terrestrial organism.
You may select one from the list below.
Aquatic: Corroboree frog, crucifix toad, green tree frog, water – holding frog,
Australia bass, barramundi, catfish and Macquarie perch.
Terrestrial: red kangaroo, potoroo, bower bird, brolga, royal spoonbill, lyrebird,
brown falcon, wedge – tailed eagle and dingo.
2. Write a brief case study about each organism using the following headings:
- The name of the organism
- The environment in which it lives
- Its method of fertilisation
- The reproductive strategies it employs to ensure that some of its gametes meet
- The relative success of the method of fertilisation
- The source of your data (reference)
CONCLUSION:
1. From your investigation, what type of fertilisation to ensure continuity of the
species best suits an aquatic environment and a terrestrial environment?
2. Write a brief conclusion to this investigation.
Discuss the relative success of these forms of fertilisation in relation to the
colonisation of terrestrial and aquatic environments.
Things to consider:
- What does discuss mean?
- Underline key words
- Use scientific language
External fertilisation is a relatively successful form of fertilisation in relation to the
colonisation of aquatic environments for the following reasons:
 There is a large amount of gametes produced both by the female and male to
ensure fertilisation occurs.
 The water environment provides support for both male and female gametes.
 Amount of zygote’s formed ensures continuity of the species.
 Cyclical reproductive behaviours
 Synchronised timing
These factors enable the gametes and young produced after fertilisation to spread out
within the aquatic environment as well as colonise large bodies of water.
Internal fertilisation is a relatively successful form of fertilisation in relation to the
colonisation of terrestrial environments for the following reasons:
 Gametes are restricted to a confined space therefore increasing the chances of
a male gamete fertilising a female gamete
 Females generally produce one gamete in a cycle, males produce copious
amounts of gametes, this increases the chances of fertilisation.
 Courtship and cyclical reproductive behaviours increases the chances of
fertilisation.
 Water is not required for successful fertilisation.
Colonisation of terrestrial ecosystems has only become possible due to organisms
overcoming the need for water. Without this need for water organisms have been able
to colonise the driest and obscure locations on our Earth.
Describe some mechanisms found in Australian flora for:
-
pollination
seed dispersal
asexual reproduction
with reference to local examples
Things to consider:
- What does describe mean?
- Underline key words
- Ensure you include local examples
Pollination: Pollination is the process by which pollen is transferred by wind or
insects to the stigma (female) of flowers. The following are some mechanisms in
Australian flora for pollination:
 The wattle relies on the wind for pollination to occur. This is not a very
reliable process for pollination to occur so the wattle produces a large amount
of pollen. This increases the chances of pollination occurring.

Bottle brushes have large spectacular red flowers. These flowers are extremely
attractive to birds. The birds are attracted to the flower in the search for nectar.
In the process of consuming the nectar the bird’s body and head collect small
amounts of pollen. When the bird flies off in the search for more food, it may
transfer the pollen to another bottle brush, therefore continuing the process of
pollination.

A male wasp pollinating an Australian orchid by accident.
Seed Dispersal: Seed dispersal is the process by which seeds are dispersed from the
parent plant by the means of wind or animal contact. The following are some
mechanisms of Australian flora for seed dispersal:
 Seeds of wire grass are spread by wind. The seed has a twisted like structure
with three hair like bristles. Once the seed has been carried by the wind and
comes to rest the hair like structures appear to burrow into the ground (assisted
by the wind) and the seed is planted.
 Harvester ants feed on many different types of seeds. They carry the seeds
closer to where they are nesting and store them underground. Once
underground the ants feed on their starch content. The seed is not
disadvantaged by this process as the plant has many seeds which may not be
eaten. The seeds which are not eaten are already underground and after a fire,
germinate to produce new plants. E.G.
Asexual reproduction: Is the process in which there is only one parent and no actual
fertilisation occurs. The following are some mechanisms in which Australian flora
undergo to enable asexual reproduction:
 Binary fission – mainly occurs in bacteria whereby cells split in two. (No flora
example)
 Spore formation – the Australian tree fern reproduces asexually by producing
spores on the underside of their fronds. These spores are distributed by wind.
 Budding – parent forms an outgrowth (bud) which is a smaller replica of itself.
Coral in the Great Barrier Reef is an example.
 Vegetative propagation – Process by which plants form new plants by using a
runner. For example Spinifex grass. (See fig 4.8.1 pg 195 of text)
Describe some mechanisms found in Australian fauna to ensure:
- fertilisation
- survival of the embryo and of the young after birth
Things to consider:
- What does describe mean?
- What is Australian fauna?
- Be succinct
There are many different ways in which Australian fauna ensures that fertilisation
occurs. For example courtship behaviours, fertilisation techniques and structures of
Australian fauna are all adaptations in which enables successful fertilisation to occur.
The following are examples of Australian fauna and some mechanisms which ensure
fertilisation and survival of the embryo/young:
Marsupials: - Fertilisation technique occurs by copulation.
- Small amount of energy/food invested at the embryonic stage.
- Short gestation period = successful development of embryo
- Young then develop in the pouch, food source obtained from mother
- Once fully developed young are expelled from pouch and fend for themselves
- RED KANGAROO, highly adapted to environment, copulation occurs,
embryo develops, fetus makes way to mother’s teat, fetus grows, fetus is born
another embryo is placed on hold, second embryo begins to develop and
makes way to pouch while joey still suckles on teat, third embryo may
develop, therefore female kangaroo may have joey at foot, joey in pouch and
embryo on hold suggesting a highly adapted and successful mechanism to
ensure fertilisation as well as the survival of the embryo and young.
Explain how the evolution of these reproductive adaptations has increased the
chances of continuity of the species in the Australian environment.
Things to consider:
- What does explain mean?
- Underline key words
- Plan an answer so that you are succinct
Through the evolution of the red kangaroo’s reproductive adaptations it has increased
their chances of continuity of the species in Australia. Such adaptations include the
dominant male of the group passing on his set of chromosomes from one generation
to the next. This ensures that the highest quality of genes is passed on from one
generation to the next. Female red kangaroo’s also can hold up to three young at any
one time. This ensures the continuity of the species because of the rapid production of
young.
Other reproduction adaptations in Australian species that ensures continuity includes;
“family ties,” whereby the organism mates with one partner only and invests a lot of
energy into the successful survival of their young. Their young then ensures the
survival of the next generation and so forth. E.G. Blue Wrens. Parthenogenesis is
another adaptation which ensures continuity within a species. This involves no
fertilisation whereby young simply develop from an egg. This enables continuity
within a species as young simply develop eliminating time for fertilisation to occur.
E.G. Bynoe gecko.
Describe the conditions under which asexual reproduction is advantageous, with
reference to specific Australian examples.
Things to consider:
- What does describe mean?
- Only include advantages as well as Australian examples
- Use scientific terminology
Australian plants use asexual reproduction as a means of continuity of the species. For
example in arid conditions where a seedling would almost find it impossible to
germinate it would be advantageous for that plant to asexually reproduce. This
circumstance is often used by Australian Spinifex grass whereby a new plant develops
with the aid of a runner from the parent plant. Another example is the Darling Lily
which reproduces both with flowers and tubers. These tubers provide nutrients for the
developing plant.
Plan, choose equipment or resources and perform a first-hand investigation to gather
and present information about flowers of native species of angiosperms to identify
features that may be adaptations for wind and insect/bird/mammal pollination
Things to consider:
- What does plan mean. (As it is a “plan” skill you will have to conduct your
own experiment, including choosing your own equipment.)
- Underline key words
- Be succinct in your answer
Explain the importance of the study of past environments in predicting the impact of
human activity in present environments
Things to consider:
- What does explain mean?
- What does impact mean?
- Understand what to question is asking before you answer it
The study of past environments has shown that human activity has a strong impact on
present environments. One concept has shown a decrease in biodiversity over time.
This means that instead of organisms multiplying or evolving there has been a decline
or increase in extinction. This lack of biodiversity is largely due to the fact that
Australia’s rainforests have been cleared or downsized for agricultural means, timber
or urban sprawl. Small pockets of rainforests are still maintained however this appears
to not maintain the organisms within it. Therefore it is evident from the study of past
environments; human impact is having a devastating affect on present environments.
Identify the ways in which palaeontology assists understanding of the factors that may
determine distribution of flora and fauna in present and future environments
Things to consider:
- What does identify mean?
- Be succinct
Palaeontology assists our understanding of the factors that may determine distribution
of flora and fauna in present and future environments in the following ways:
- Palaeontology is the study of fossils from the past. Scientists can then
formulate under what conditions these organisms lived.
- Fossils found in similar areas indicate the distribution of that species.
- Knowing the distribution of that species scientists may be able to determine
what environment that organisms lived in.
- From the above information scientists may be able to make links between
species and the type of environment which suits and therefore its distribution.
Explain the need to maintain biodiversity
Things to consider:
- What does explain mean?
- What is biodiversity?
- Understand the meaning of the dot point before answering the question
Firstly biodiversity is the diversity among plant and animal species within an
environment. In recent times there has been a great need to maintain biodiversity as
recent studies have shown the decline in certain species within Australia such as the
koala. The main cause of the decline in Australian species is the intervention of
humans and their impacts on the environment. Human impact includes the destruction
of natural habitats for agricultural gain, destruction of land to build houses and cities
and generally using the land for societal gains. The effect of human activity on
ecosystems includes the decline in biodiversity, including the drop in numbers of
certain species who are unable to cope with the change, species are susceptible to
extinction as well as the general decline of all species when an ecosystem is affected
by human activity. Therefore there is a need to maintain biodiversity as if not
maintained large proportions of animals and plants will decline in number or become
extinct.
Gather, process and analyse information from secondary sources and use available
evidence to propose reasons for the evolution, survival and extinction of species, with
reference to specific Australian examples
Things to consider:
- What do the following words mean; gather, process and analyse.
- You need to give reasons for the evolution, survival and extinction of species.
- Ensure you give Australian examples.
http://www.amonline.net.au/thylacine/
http://www.naturalworlds.org/thylacine/
Process information to discuss a current effort to monitor biodiversity
Things to consider:
- What does process and discuss mean?
- Underline key words
- The worksheets that were handed out recently outline this dot point.
The following is a list which illustrates Australia’s effort to monitor biodiversity:
 1992, Australia signed the Convention on Biological Diversity. This ensured
that Australia would take action to protect their biodiversity. The three main
aims of the convention were as follows; conservation of biodiversity,
sustainable use of its components and the fair and equitable use of the benefits
arising from the use of genetic resources.
 In 2002 all countries that signed the convention agreed that by 2010 their rate
of biodiversity loss would be minimised. This is known as the 2010
Biodiversity target.
 2005 U.N. released study known as Millennium Ecosystem Assessment. Study
aimed to show the degradation taking place and the effort required to obtain
the 2010 biodiversity target.
 2006 World Conservation Union released its Red List of Threatened Species.
 Australian Government has a National Strategy for the Conservation of
Australia’s Biological Diversity. NSW government has NSW Biodiversity
Strategy. These strategies are all in place to ensure that conservation takes
place within the individual, community and national levels.