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Science Stage 4 NEW SOUTH WALES D E PA R T M E N T OF EDUCATION AND TRAINING Australian environments Set 3: Another look at organisms Number: 40631 Title: Australian Environments This publication is copyright New South Wales Department of Education and Training (DET), however it may contain material from other sources which is not owned by DET. We would like to acknowledge the following people and organisations whose material has been used: Extracts from Science Syllabus Years 7-10 @ Board of Studies, NSW 2003 Photograph © Tom Brown Photographs © Jane West Photograph © Julie Haeusler Introduction pp vii-x Set 1 p 3 Set 1 p 18, Set 2 p 9, Set 5 p 5 Set 1 p 36 COMMONWEALTH OF AUSTRALIA Copyright Regulations 1969 WARNING This material has been reproduced and communicated to you on behalf of the New South Wales Department of Education and Training (Centre for Learning Innovation) pursuant to Part VB of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act. CLI Project Team acknowledgement: Writers: Editor: Illustrators: Rhonda Caddy, Monika Khun, Michael Manahan Jane West Tom Brown, Barbara Gurney and Rhonda Caddy All reasonable efforts have been made to obtain copyright permissions. All claims will be settled in good faith. Published by Centre for Learning Innovation (CLI) 51 Wentworth Rd Strathfield NSW 2135 _______________________________________________________________________________________________ _ Copyright of this material is reserved to the Crown in the right of the State of New South Wales. Reproduction or transmittal in whole, or in part, other than in accordance with provisions of the Copyright Act, is prohibited without the written authority of the Centre for Learning Innovation (CLI). © State of New South Wales, Department of Education and Training 2005. i Australian environments Here are the names of the lessons in this unit. Set 1 ☞ Who cares? Lesson 1 Lesson 2 Lesson 3 Lesson 4 Lesson 5 Do you care? Who is interested in environments? Environmental jobs Looking at Australian environments Describing ecosystems Set 2 A closer look at relationships Lesson 6 Another look at living things Lesson 7 Who eats what? Lesson 8 Decomposers Lesson 9 Food chains Lesson 10 Food webs Set 3 Another look at organisms Lessons 11 and 12 Adaptations Lessons 13 and 14 Endangered organisms Lesson 15 Australians who study organisms Set 4 Look for yourself! Lesson 16 Lesson 17 Lesson 18 Lesson 19 Lesson 20 Looking more closely Looking around you Sensing your environment Animals in your environment Temperature and rainfall What happens if? Lesson 21 Lesson 22 Lesson 23 Lesson 24 Lesson 25 What if there is a bushfire? What if there is a drought? What if there is a flood? What if humans keep making changes? Over to you Set 5 Australian environments Set 3 ii Set 3: Another look at organisms Contents What will you learn in Set 3? ...................................................................iii What do you need for Set 3? ....................................................................iv Lessons 11 and 12 Adaptations............................................................ 1 Lessons 13 and 14 Endangered organisms....................................... 17 Lesson 15 Australians who study organisms .................... 25 Suggested answers ................................................................................... 29 Send-in pages ............................................................................................ 35 Australian environments Set 3 iii What will you learn in Set 3? In Set 3, you will have opportunities to: • describe some adaptations of living things • explain how adaptations help an organism to survive in its environment • match drawing of animals with their descriptions • explain the meanings of extinct and endangered • describe why some organisms become extinct or endangered • extract information from a media article • describe the research of a current Australian scientist • discuss the impact (or effects) of this research. Australian environments Set 3 iv What do you need for Set 3? Here is a reminder of the items you need for Set 3. All lessons • various materials, such as books, CD-ROMs, videos and Internet resources with information about organisms • hand lens Lessons 13 and 14 • scissors • glue or sticky tape Australian environments Set 3 1 Lessons 11 and 12 Adaptations Organisms (living things) need all sorts of things to stay alive. They have to find food, water and shelter. They often have to find companions and a mate to reproduce. They need to avoid danger and animals that might eat them. Organisms have special features to help them to survive. Different organisms have different features. These features are called adaptations. Adaptations make organisms suit their environment. Some examples of adaptations 1. An owl hunts small animals such as mice. An owl hunts at night. It can see very well in the dark. What features does an owl have to help it to catch its food? Please check your answer. 2. Wombats mainly eat grasses. They dig burrows in the ground to shelter from the heat and to hide from animals that might kill them. Wombats have poor eyesight but a very good sense of smell. What features does the wombat have to help it to survive? Check your answer now. Australian environments Set 3 2 3. A gum tree is a plant. All trees take in water through their roots. They lose water through their leaves. Gum trees have deep roots and hard waxy waterproof leaves. They survive very well in the dry climate of Australia. Describe some features of the gum tree that help it to survive. Check your answer. You have described some features of an owl, a wombat and a gum tree. These features help them to survive. So these features are adaptations. The adaptations of the owl, wombat and gum tree make them suit their environments. 4. What is an adaptation? 5. Emus are tall flightless birds that live in Australia. They eat fruit and plants. They can run very fast. They have large eyes and strong beaks. They are a dull red brown colour, like the soil. Describe some adaptations of the emu. Well done! You can describe the adaptations of some living things to their environment. Australian environments Set 3 3 What about you? What adaptations do you have? Try these questions. 6. Why do you think humans have hair on their heads and lashes on their eyes? 7. What does your heart do when you have to run quickly? (This is an adaptation because it helps you to survive.) 8. What do you do if you feel cold? (What you do is an adaptation because it helps you to survive.) 9. Can you think of any other adaptations that you have? Describe two. Compare your answers with the ones in the answer pages. You have adaptations that help you to survive in your environment. And you’ve noticed that you have different kinds of adaptations. Adaptations that are features or structures of your body are called morphological adaptations. Adaptations in how your body works are called physiological adaptations. Adaptations in how you act and what you do are called behavioural adaptations. Australian environments Set 3 4 Kinds of adaptations Morphological (or structural) adaptations are often visible features of an organism. They are related to the way the organism looks or is structured. Here are some examples. • Some animals have special colours or patterns, for attracting a mate or for camouflage (to help the animal to hide). For example, male bower birds have some bright blue feathers whereas females are brown. • Some flowers have special colours, patterns and perfume to attract insects and so help the plant to reproduce. For example, wattles are bright yellow and have strong perfume to attract bees. • Some animals have spines to protect themselves from predators. For example, echidnas are covered with spiny needles. • Some plants have special seeds to protect the seeds or to help them disperse (spread out). For example, hakea seeds are in a tough pod that opens after fire. Each seed has a wing to make it fly. Physiological (or body function) adaptations are related to the way that an organism carries out its life processes. These adaptations affect the internal functioning of the organism and usually are not immediately visible to an observer. Here are some examples. • Marsupial animals, such as possums, give birth to tiny babies that are protected and cared for in a pouch. • Humans produce perspiration (sweat) to cool the body down. • Kangaroos reduce the amount of water they lose by making their urine very concentrated (with lots of wastes dissolved in a little water). Behavioural (or what the organism does) adaptations include responses to a specific stimuli (things that happen to cause a reaction). Behavioural adaptations include individual and group responses. Here are some examples. • Penguins huddle together to keep warm. • Plants droop their leaves to reduce the amount of water they lose. • Kangaroos lick their paws to keep cool. • Plants grow towards the sunlight. Keep these three different kinds of adaptations – morphological, physiological and behavioural – in your mind as you learn about the variety of adaptations of some plants and animals. Choose the ones that interest you from the next 16 pages. Australian environments Set 3 5 Adaptable plants Here are some examples of plants with different adaptations. baobab tree grass tree cactus mangrove Venus fly trap stringy bark 10. Use information in the pictures to complete as much of the table as you can. Plant adaptation Name(s) of plant example special tissue for holding water absorbs extra nutrients by catching insects narrow leaves to reduce loss of water Use the answer pages to fill in any gaps in your table. Australian environments Set 3 Predict an ecosystem where it might be found 6 All plants have special features that enable them to survive in the environment in which they live. They have morphological, physiological and behavioural adaptations to help them. Roots Roots serve two main purposes for a plant. • Roots anchor, or hold, the plant in the ground, providing support for the plant. • The plant absorbs all its minerals and water through its roots. Roots are covered by lots of tiny hairs, called root hairs, which increase the surface area through which absorption can take place. Roots usually fall into either of two main types: the tap root or the fibrous root. tap root fibrous root 11. What is an advantage of each of these types of roots for the plant? tap root ______________________________________________________________________________________ fibrous root ________________________________________________________________________________ Check your answer. Roots usually behave by growing downwards. But not always! Australian environments Set 3 7 Some plants live in soggy areas that tend to have a lot of water around all the time. An example is mangroves, which grow in estuaries where a river meets the sea. Mangroves have special roots called pneumatophores (say new-MAT-a-faws). These roots grow upward out of the muddy river bottom, instead of down, so that the roots are exposed to air at low tide. This lets the roots get oxygen so that the cells in the roots can carry out respiration to get the energy they need. mangrove Roots are also useful for propagating some plants. (Propagating means making new plants or reproducing.) Plants such as grasses, some vines and strawberries use runners either above ground or below ground to reproduce themselves. grass runners strawberry runners An activity for you to try Go into the garden and see if you can identify some plants that have runners. Look for vines, grasses and plants used as shrubbery or ground covers. You may be able to gently pull some up and take a closer look. What would happen if you cut these and replanted the cut sections? Try it. You will need to provide adequate water to these newly planted sections over the next few weeks for them to keep growing. Australian environments Set 3 8 Leaves Leaves are necessary for plants to absorb sunlight (light energy) for the process of photosynthesis. Photosynthesis is necessary for all plants to make the sugars (food) they require for their life processes. Leaves on different plants have different shapes and sizes so that each plant can maximise its exposure to sunlight, without losing excessive amounts of water through the leaves. Look at the examples below. These leaves are not drawn to scale and are really very different sizes. baobab banksia she oak bangalow palm iron bark blackbean Big leaves enable the plant to gain maximum exposure to sunlight but in dry, hot and windy conditions, big leaves will result in the loss of large quantities of water through stomates in the leaves. Stomates (or stomata) are tiny structures on the surface of the leaf that allow gases to move in and out of spaces inside the leaf. Water moves out of the leaf through the stomates as water vapour. To reduce this loss of water as much as possible, the majority of stomates are located on the underside of a leaf, so that they are facing away from the Sun. The stomates can also be sunken into the leaf so that they are not directly exposed to light energy. Australian environments Set 3 9 Some plants, such as the eucalypts, have narrower leaves to reduce the amount of surface exposed to the Sun. Their leaves are also very firm and leathery to prevent water loss. Pine needles are also an adaptation to minimise water loss since the extremely cold climate where pine trees grow is also very dry. It is dry because most of the moisture is frozen and so plants need to reduce water loss by reducing the size of the leaves. Cactus leaves (the spines) have adapted in the same way, only they have very swollen succulent stems that hold moisture. 12. Look closely at the diagrams of leaves on page 8. If you were a plant living in a very hot dry climate, which leaves would you prefer to have? How would they assist you in surviving? Please read the comments in the answer pages. Leaves also need protection from animals. Some leaves have sharp spines, serrated edges (bumpy edges like a bread knife) or simply have a bad taste. 13. Look back at the plants on page 5. Which ones do you think have adaptations to protect them from predators? Check your answer. Leaves also have behavioural adaptations. For example, spinifex grass can roll its leaves during dry conditions to reduce water loss. Most plants grow towards sunlight – this is called phototropism. And of course, there are many physiological adaptations of plants. For example, plants such as mosses and ferns (that grow under trees and ledges where it is darker) have adaptations so that they do not need as much sunlight as other plants for photosynthesis. Australian environments Set 3 10 Stems Stems of plants provide support for the plant and enable them to stand upright. They are either woody or very flexible and filled with sap. Plants that grow very tall, such as trees, require extra strength and tend to have very thick trunks. The branches, however, are more flexible so that they do not break in the wind. Plants respond to conditions around them as they grow. For example, plants in windy areas tend to grow lower to the ground or to grow in the same general direction as the wind so that they do not get battered excessively. Flowers and fruit Flowers are the reproductive organs of plants. They contain special structures to enable male sex cells (in pollen) to join with female sex cells so that seeds form. Every plant species has a specially adapted, and different, type of flower. For example, many plants rely on wind to carry pollen from one flower to another. The pollen must be formed high in the flower, not hidden away in the petals, so that wind can blow it to another flower. Flowers that rely on animals to carry pollen have adaptations of perfume, nectar and bright colours to attract animals. Their pollen is usually sticky or spiky so that it clings to an animal when it visits the flower. The seeds produced by different plants are also unique. If the seed is to be spread by wind, it is very light and may have wispy attachments so that it blows away easily. Other seeds are contained in very brightly coloured fruit, so that animals will eat the fruit and the seeds will be spread via the animals’ droppings. Some fruit is very tough and requires very high temperatures, such as a bushfire, to split it open. This is very common among some native Australian species. In very dry areas, such as desert regions, plants have very short flowering cycles, usually coinciding with periods of rain. The flowers bloom and produce seeds very quickly so that new seedlings are established before the next seasonal dry spell. Australian environments Set 3 11 Adaptable animals Animals are very adaptable creatures and no two species are exactly alike. They have developed unique features to cope with their surroundings and have managed to survive in some very desolate places on Earth. In this section you will look more closely at some adaptations of animals that assist their survival in different conditions. Animals on land Animals that live on land are called terrestrial animals. They need different adaptations from aquatic animals because they live in a different environment. What are some of these special features? Support Air is very thin compared with water. It does not provide any support to organisms. Animals need to have very strong skeletons to hold them up, to protect their organs and to let them move. Skeletons may be exoskeletons on the outside, such as the ‘shell’ on a beetle. Skeletons may also be endoskeletons, on the inside, such as the skeleton in your body. Compare the endoskeletons in these animals. Terrestrial animals have thicker stronger bones than aquatic animals. Australian environments Set 3 12 Water loss Animals on land face a major problem with losing water. Animals must keep lots of water within their cells – for example, approximately 70% of human body tissue is composed of water – because water is essential to maintain life processes. Animals have behavioural adaptations to help reduce water loss. They can move away from heat and tend to live close to sources of water. Most animals will move to search for water in times of drought. Land animals have internal lungs or respiratory organs to prevent water loss. Also, their methods of reproduction do not tend to depend on water. Land animals either produce eggs which contain their own fluid or rely entirely on internal methods of reproduction. Availability of light and temperature control Availability of light is not an issue for animals on land as they do not gain any direct benefit from exposure to light. However, light is associated with temperature, which is a major concern for animals as it is directly related to water loss and maintenance of body temperature. Temperature varies significantly on land, from place to place, season to season and on a daily basis within a given region. Land absorbs heat easily and also loses it quickly; that is why the coastal regions are usually cooler than inland areas during the day and vice versa at night. Animals have some very ingenious ways of avoiding extreme temperatures. These include the type of body covering they have, sweating and producing concentrated urine. Many animals burrow to avoid the hottest part of the day or only come out at night. The size and shape of an animal is also related to its ability to regulate its body temperature. Some animals can change colour to absorb or reflect more light. For example, some reptiles can go dark when they need to absorb heat from the Sun’s rays, or get lighter in colour when avoiding exposure to excess heat radiation from the Sun. (Snakes are reptiles so their body temperature changes with the surrounding temperature. They have to absorb or reflect heat to keep their body temperature in control.) Australian environments Set 3 13 Colour Colour can be a very good disguise for animals. This adaptation is called camouflage and it can help them to hide and to protect themselves from predators. A camouflaged animal tends to blend in completely with its surroundings, making it difficult for other animals to see it. Colour is also used to attract a mate; for example, male bower birds collect blue objects to decorate their nests to attract females. Most male birds are more colourful than the females, which would usually sit on the nest and so need to blend in with the surroundings. Obtaining food Animals have unique adaptations for gathering food, such as: claws for digging; special teeth for tearing, cutting or chewing food; scents that lure victims; silk nets that can trap unsuspecting passers; beaks that can crush, peck or reach into very small places. Look at these examples. albatross wedge-tailed eagle bridled honeyeater spoonbill rainbow lorikeet long-tailed finch northern shoveler duck collared kingfisher Australian environments Set 3 14 Can you suggest what each of the birds on page 13 might eat? Hint: Look at the size and shape of the beak. Does it look thin and pointy for getting into small places, strong and sharp for cutting or tearing, or small for pecking the ground? Go outside and observe the birds in your garden for a few clues. Draw up a table with your answers in the space below. Compare your answers with the ones in the answer pages. Other adaptations Some animals have special adaptations to protect themselves. These include the ability to produce poison, warning scents, noises and ability to get away from danger. Think of an animal with a protective adaptation. Describe it below. There are some examples in the answer pages. Australian environments Set 3 15 All animals need some protection from their surroundings. For example, some have very hairy nostrils and eye lashes to prevent sand and dust from getting into the eyes or lungs; others have thick fur to provide insulation or water-resistant feathers to avoid getting soaked in the rain or water. (Wet feathers would decrease the ability to fly.) Big eyes assist nocturnal (night) vision and long whiskers can help animals to sense things in reduced light. Animals also need to be able to find a mate and many animals have special morphological, physiological and behavioural adaptations to make reproduction more likely. If you are interested in adaptations, there are lots of books, videos and CD-ROMs that you could investigate to find out more. Exercise 11 But now it is time to complete the send-in exercise for Lessons 11 and 12. Australian environments Set 3 16 Australian environments Set 3 17 Lessons 13 and 14 Endangered organisms Have you seen a dinosaur recently? I don’t mean a photo or a model. A real dinosaur. No? I wonder why not? Dinosaurs were large reptiles that lived on Earth millions of years ago. And now they are no longer here. That diverse group of animals is now extinct. Extinct means has died out. No one is sure exactly why the dinosaurs became extinct. There may have been climate changes or disease; there could have been a major disaster. The extinction probably took a very long time. They became extinct because they did not have the adaptations to survive when their environment changed. What are endangered organisms? Living things continue to become extinct, even today. As well, some organisms are endangered. This means that there is a high chance that these organisms will become extinct. Use the pictures of animals on page 41 to complete the diagram below. Some of Australia's endangered animals Native cat Numbat an animal with large ears, large eyes and long whiskers a furry animal with a bushy tail and stripes Bettong Orange-bellied parrot a jumping animal with large feet and a rounded body an animal with a strong beak and feathers Australian environments Set 3 18 More examples This animal is called a Thylacine, or Tasmanian tiger. It is extinct. It was hunted by farmers because it killed sheep. The forests where it lived were cut down for wood and cleared for farmland. 1. The Thylacine is extinct. What does this mean? 2. Why is the Thylacine extinct? This animal is called a long-footed potoroo. It is endangered. It has been killed by foxes and wild cats. The forest where it lives has been changed by logging (cutting down trees). 3. The long-footed potoroo is endangered. What does this mean? 4. Why is the long-footed potoroo endangered? You have looked at examples of extinct and endangered animals. All sorts of organisms – plants, animals and decomposers – can become endangered or extinct. Australian environments Set 3 19 You have thought about some reasons that organisms become endangered or extinct. These include: • that they are easy prey for predators brought into Australia, such as foxes, cats and dogs • that they have been hunted over many years and so their numbers are greatly reduced • that their natural habitat has been changed by: human activity, such as clearing for towns, agriculture and industry; the effects of pollution; the rapid growth of technology. 5. Here are some steps that are recommended to protect Australian organisms from extinction. Explain why each one would help. (a) Pet cats should be indoors animals. They should be shut inside the home at night. (b) Cars should be washed on the grass. Waste car oil and wastes from pets should be disposed of properly and not washed into street drains and so into rivers and waterways. (c) Areas of bushland should not be altered until they have been studied to see which organisms live there. Compare your explanations with the ones in the answer pages. Australian environments Set 3 20 Some more of Australia's endangered animals Read about these endangered animals and look carefully at the drawings. You will then better understand why they are in danger of extinction. Western swamp tortoise This is the world's rarest tortoise and one of Australia's most endangered animals. It has been successfully bred in captivity but less than 300 remain in the wild. Bridled nailtail wallaby This is one of the most beautiful of Australia's wallaby species. It has been reduced to 10% of its former range. It was thought to be extinct until a population was discovered in central Queensland in 1973. Northern hairy nosed wombat This is Australia's rarest mammal and vies for a lead position among the world's endangered animals. Only 65 survive but are protected in Epping Forest, Queensland, a scientific reserve of 3 330 hectares. New words – what do they mean? In the list below are some words you have just read. You might like to know what these words mean. brindled – grey-brown coloured with darker spots or stripes in captivity – in a human-made enclosure rare – not widely known, uncommon range – the limits to which the animal is spread out vies – competes with other animals Australian environments Set 3 21 Extract information from the descriptions about these Australian endangered animals and answer the following questions. 6. How many western swamp tortoises are there in the wild? 7. When was the population of bridled nailtail wallabies first discovered? 8. Where is the only population of northern hairy nosed wombats? 9. A recovery plan is underway for the bridled nailtail wallaby. What do you think this means? 10. Why do you think that bridled nailtail wallabies became endangered? 11. Two of the world’s most endangered species are on this Australian list. Which species are they? Check your answers in the answer pages. Australian environments Set 3 22 Some of the world's endangered animals Many species in other parts of the world are also in danger of extinction. Read about three other endangered species in the boxes below. Look carefully at the drawings. Then answer the questions on the next page. Giant panda A cooperative project between the World Wildlife Fund and the People's Republic of China began in 1980 to learn more about the giant panda and to ensure its conservation. Only an estimated 1 000 pandas remain, all confined to the bamboo forests of south-western China. Scarcity led to their adoption as the emblem for the World Wide Fund for Nature. Blue whale The blue whale is found in all oceans. It is the largest animal on Earth. It has been heavily exploited in modern times; for example, in 1930–31, more than 30 000 were slaughtered. The species was finally protected in 1967 but is still endangered. Aye-aye Found only in the northern sector of the east coast rainforests of Madagascar, this solitary creature sleeps in a nest by day and feeds on fruit and insect larvae by night. An important cause of its disappearance is prompted by its bizarre appearance; many Malagasy consider it a creature of ill-omen to be killed on sight. It has recently been successfully bred in captivity. Australian environments Set 3 23 New words – what do they mean? The following list explains the meanings of some words which may be new to you. cooperative – working together, helping conservation – stopping further killing estimated – to calculate an approximate number emblem – a badge or symbol protected – agreement to defend the animal from harm solitary – an animal which lives alone larvae – immature, free swimming stage of insect life Malagasy – the people of Madagascar ill-omen – bad luck Can you extract more information on endangered species? Answer the following questions. 12. Which animal is used as the emblem for the World Wide Fund for Nature? 13. Which of the endangered species is the largest animal on Earth? 14. What happened to blue whales in 1930–31? Why? 15. What is an important cause for the disappearance of the aye-aye? Please check your answers. Australian environments Set 3 24 Exercise 13 In send-in Exercise 13, you will find out about another endangered or extinct organism. There are two ways you could do this. • You can carry out your own research to find information about an organism. You need to describe where it lives/lived and why it is endangered or extinct. You can present your information on your own paper or in another way that you choose. You can show that you are performing at a high level in science if you choose to complete Exercise 13 in this way. • If you would like a simple way to complete Exercise 13, read the information and answer the questions in the send-in pages. Australian environments Set 3 25 Lesson 15 Australians who study organisms There are many people in Australia who study living things. Many of these people have jobs as scientists at universities or at the CSIRO (Commonwealth Scientific and Industrial Research Organisation). Your task in this lesson is to learn about what one scientist does. There are different ways that you can do this. Choose the way that you will enjoy the most (or follow your teacher’s instructions). You could: ❒ ❒ ❒ read the information and answer the questions on pages 25 and 26 ❒ prepare your own report using information that you find for yourself. If you want to do this, read the instructions on page 28. use information from pages 26 and/or 27 to complete Exercise 15 use information sent to you by your teacher or information that you find for yourself to complete Exercise 15 Decide how you will complete this lesson and do it. Happy learning! Studying Sydney Harbour Dr Lynne McLoughlin is a biologist at Macquarie University in Sydney. She has studied how ecosystems around Sydney Harbour have changed since Europeans first took over the area in 1788. Dr McLoughlin has found that all areas of the harbour have changed greatly. Dr McLoughlin collected information from government records, newspapers and other reports. She also studied paintings and photographs taken around Sydney Harbour. She made some interesting doscoveries. Mangroves used to only occur around the openings of creeks and rivers but now they are quite common in the harbour. One reason for this is that there are more mudflats because soil is being washed into the harbour from cleared land. Now, communities such as beabches and saltmarshes are much less common in the harbour. Australian environments Set 3 26 The harbour has also been changed by dredging, which means digging soil from the bottom to make the harbour deeper. This began in 1842 and continued until the 1960s. Many of the areas around the harbour have been filed with soil and garbage and turned into parks. Retaining walls of concrete and stone replace natural tidal areas. Dr McLoughlin's research is important because it helps people to see that 'natural' communities may be due to chan ges that people have made—they may not be natural at all. It helps people to make decisions about ecosystems to protect. 1. Underline the name of the scientist. 2. Describe what this scientist has found out. 3. Why is this information useful for Australians? More Australian scientists There is information about two more Australian scientists following. Choose the research that you think is more interesting and use it to complete the send-in page for this lesson. Dr Bill Rudman Dr Rudman works at the Australian Museum in Sydney. It is called the Australian Museum because it was the first museum established in Australia (1827). The main areas of research at this museum include Australian Aboriginal culture and Australian organisms, rocks and minerals (natural history). Dr Rudman has studied sea slugs, called nudibranchs, that get most of the food they need from microscopic plants called zooxanthellae. These algae (sea plants) naturally grow on the surfaces of corals. The sea slugs eat the corals, with the algae attached, then keep the algae alive inside their bodies. Australian environments Set 3 27 Sunlight can travel through the bodies of the sea slug to reach the algae, so the algae can photosynthesise and make sugars. The sea slugs use these sugars from the algae. Understanding how these organisms survive together provides information about the richness of relationships in nature. Studies of the mechanisms by which sea slugs are able to maintain algae inside their bodies may assist scientists to understand and control relationships between other organisms, including parasites and hosts. Dr Chris Smith, Dr Warren Bond and Mr Frank Dunin These scientists from the CSIRO have been working with farmers in the Wagga Wagga area to measure the amount of water used by agricultural crops. Smith, Bond and Dunin used huge pots to hold water under the soil. By weighing these pots very accurately, they could determine how much water the plants had used and how much water had leaked through the soil into the water table. They have been able to compare the efficiency of different crops to prevent leakage. Leakage of water is a problem because salt rises towards the surface when the water table is high. This makes the soil salty, which is called salination, and reduces the ability of the soil to grow plants. Contrary to usual thinking, plants that use more water – like the native plants that were cleared for farming – are better for this area. This is because they keep the water table lower and so stop salt rising towards the surface. Smith, Bond and Dunin have measured the efficiency of several crops to prevent water leakage. These crops include wheat and triticale, lucerne and canola. They have also measured the water leakage for native vegetation. By comparing their measurements, they can make recommendations about crops that are best for preventing leakage of water into the water table, and so, best for reducing salination. So far, their research shows that lucerne is a very good crop for preventing leakage. They have experimented with farmers and found that rotating lucerne and another crop reduces the salination of the soil. The best crop to reduce leakage would be trees but trees grow too slowly to be a commercial crop in most areas. Australian environments Set 3 28 Didn’t like these examples of Australian scientific research? There is lots of other information from universities and other organisations available via the web. Think of an idea and search for information using a search engine. Exercise 15 You can now complete Exercise 15 in the send-in pages. If you are preparing your own report make sure that you have: • identified the scientist(s) • described what organism(s) the scientist is studying and what s/he has learned • discussed how this information could be useful or perhaps lead to problems. Australian environments Set 3 29 Suggested answers Lessons 11 and 12 Adaptations Some examples of adaptations Page 1 Page 2 Page 3 1. An owl has large eyes to see at night. It has strong wings to fly quickly and claws to grab small animals. It has a sharp hooked beak for tearing food. 2. A wombat has a good sense of smell to find food and to avoid animals that could kill it. It has strong claws and legs for digging. You might also say a wombat has strong jaws and teeth for chewing grasses. 3. A gum tree has deep roots to reach for water. It has hard waxy leaves to prevent water escaping. Because gum tree leaves are hard, they do not dry out or wilt as quickly as other trees’ leaves. 4. An adaptation is a feature that helps an organism to survive in its environment. 5. An emu can run quickly. It has large eyes to see food and enemies and a strong beak to eat fruit and plants. Its colour helps it to hide. What about you? 6. Hair on the head insulates and protects the head. It stops too much heat being lost and stops the skin from being sunburnt. Eyelashes protect the eyes because they stop dust and grit getting into the eyes. These foreign materials could scratch the surface of the eyes and impair vision. 7. Your heart beats faster (to quickly move sugar and oxygen through your body to your muscles and to move carbon dioxide to your lungs to be excreted). 8. You put on a jumper (or you shiver). Both these behaviours are adaptations to keep you warm. 9. You have many adaptations. For example, you have: • two eyes to enable you to see in three dimensions • • a large brain to solve problems and use symbols and words a thumb that works in the opposite direction from your fingers so that you can grasp. Australian environments Set 3 30 Lessons 11 and 12 continued Adaptable plants Page 5 10. Here are some sample answers. Plant adaptation Name(s) of plant example Predict an ecosystem where it might be found special tissue for holding water boabab tree cactus desert absorbs extra nutrients by catching insects Venus fly trap scrubland ecosystems with poor soils narrow leaves to reduce loss of water boabab tree stringy bark desert scrubland Roots Page 6 11. A tap root goes deep into the ground, to get deep water and as an anchor. A fibrous root spreads out to get water from a large space around the plant. Leaves Page 9 12. If you were a plant in a hot dry environment, you may prefer to have leaves like the banksia, iron bark or she oak. They are thinner than the others and would reduce the surface area from which water loss, called transpiration, could occur. 13. Grass tree leaves are razor sharp; a cactus has spines; the Venus fly trap looks spiky but it isn’t. Australian environments Set 3 31 Lessons 11 and 12 continued Obtaining food Page 14 Here is an example of a suitable table and some suggested answers. Bird Possible food albatross small prey, aquatic organisms from shallow water or scavenged on the seashore spoonbill crustaceans found in mud or shallow water northern shoveler duck scavenges small organisms in shallow water wedge-tailed eagle small prey such as rats, lizards, snakes rainbow lorikeet nectar and seeds collared kingfisher small prey such as lizards, mice brindled honeyeater nectar from flowers long-tailed finch grass seeds Other adaptations For example: spiders and snakes producing venom; kangaroos are able to move very fast; echidnas have spines; geckos will be pale coloured in areas with white sand or mottled when surrounded by pebbles of varying colour. Australian environments Set 3 32 Lessons 13 and 14 Endangered organisms What are endangered organisms? Page 17 Here are the animals. Native cat Numbat an animal with large ears, large eyes and long whiskers a furry animal with a bushy tail and stripes Bettong Orange-bellied parrot a jumping animal with large feet and a rounded body More examples Page 18 Page 19 1. The Thylacine has died out. There are none of them alive any more. 2. The Thylacine was killed by people. The places where it lived were changed or destroyed. It did not have the adaptations it needed to survive when its environment changed. 3. The long-footed potoroo might become extinct. There are not very many of these animals left. 4. It is killed by foxes and cats. The places where it lived were changed or destroyed. 5. (a) Cats are carnivores. They like to hunt at night. Keeping them inside will stop them from hunting and killing native animals such as small birds, lizards and mammals. (b) Wastes should not be put into gutters and so into rivers and waterways. They could poison or give diseases to native organisms that live in our rivers and oceans. (c) A bushland area may be home to an endangered species. If the area were changed, the species could become extinct. So, the area should be studied first. Australian environments Set 3 33 Lessons 13 and 14 continued Some more of Australia’s endangered animals Page 21 6. less than 300 7. 1973 8. Epping Forest, Queensland 9. People are working to help this wallaby survive and reproduce so that the numbers will increase. The wallabies may be captive or in the wild. 10. Perhaps people have taken its habitat by clearing land for farms? Perhaps the wallabies’ habitat has been changed in some other way? 90% of the space and resources that the wallabies used to have are now no longer available. 11. western swamp tortoise, northern hairy nosed wombat Some of the world’s endangered animals Page 23 12. giant panda 13. blue whale 14. They were killed by people. People wanted to use them. (Whale oil can be used as a fuel and to make soap and perfume.) 15. People kill them because they are frightened that the animals will bring bad luck. Lesson15 Page 26 Australians who study organisms Studying Sydney Harbour 1. Dr Lynne McLoughlin 2. Dr McLoughlin has found out that the ecosystems around Sydney Harbour have changed greatly since 1788. 3. It helps people to make decisions about which ecosystems in Sydney Harbour should be protected. Australian environments Set 3 34 Australian environments Set 3 35 Send-in page Name Lessons 11 and 12: Adaptations ______________________________ Exercise 11 This exercise is an opportunity for you to show that you can: • describe some adaptations of living things to factors in their environment • write explanations to match the adaptations you select. Below are some sentences about different plants and animals. Choose at least one plant and one animal that you would like to write about. For each organism you choose: • describe two adaptations that benefit the organism • explain how each adaptation helps it to survive. Giraffes Giraffes are herbivores that live in the drier parts of Africa. Food is sometimes scarce. They are very tall animals with long necks. They have patched markings which are similar colours to the regions where they live. Australian environments Set 3 36 Moss Moss is a plant which does not have true roots. Instead, it is held in place by fixings called rhizoids. Moss gets its water from the moisture on the surfaces where it lives. It needs light for photosynthesis but must live in cool shady places. Polar bears Polar bears live on ice and snow in the Arctic. They prey on seals, penguins and fish. They have thick soft white fur and thick layers of fat. They have strong sharp claws and can run and swim very quickly. Neptune’s necklace Neptune’s necklace is a sea plant. It is a producer that lives in the ocean. Most light for photosynthesis is at the water surface. Each piece of the necklace is filled with air so that it floats. Hundreds of pieces join together to form a colony of this seaweed. Australian environments Set 3 37 Send-in page Name Lessons 13 and 14: Endangered organisms ______________________________ Exercise 13 This exercise is an opportunity for you to show that you can: • extract information from a scientific description • apply information to explain why adaptations are important. Below there is information about an endangered reptile called an angonoka. Read through the information now. Angonoka Extremely rare and in imminent danger of extinction, the angonoka is restricted to three islands of forest in northwest Madagascar. The species is entirely herbivorous. The main threats to its survival are commercial and subsistence exploitation, habitat modification and predatory feral pigs. Here are some words from the information that may be new to you. imminent – just about to happen herbivorous – the animal is a herbivore subsistence – day to day survival exploitation – taking or killing more than are needed modification – changes feral – a domestic animal gone wild Australian environments Set 3 38 Now read the information about the angonoka again. Then answer the questions under the information. 1. What does the angonoka eat? 2. Underline the words that best match the angonoka. producer predator plant consumer prey animal 3. Write two reasons that the angonoka is endangered. 4. How do you know that there are not many angonokas left in the world? 5. There are other forest areas near where angonokas live. Why don’t these animals spread into other areas so that they can survive? Australian environments Set 3 39 Send-in page Lesson 15: Name ______________________________ Australians who study organisms Exercise 15 This exercise is an opportunity for you to show that you can: • describe some recent Australian scientific research • evaluate what effect this research might have • discuss some benefits and possible problems that may come from this new information. Complete the tasks below, using information from pages 33 and/or 34 or information your teacher has provided or that you have found for yourself. 1. Who is the scientist and what has been discovered? 2. How might this new information affect other people? Explain why you think so. Australian environments Set 3 40 If you want to prepare your own report, use the lines or space below. Make sure that you : • identify the scientist(s) • describe what organism(s) the scientist is studying and what s/he has learned • discuss how this information could be useful or perhaps lead to problems. Australian environments Set 3 41 Endangered Australian animals Use these drawings in Lessons 13 and 14 Australian environments Set 3 42 Australian environments Set 3