Evolution of Australian Biota

Transcription

1 Biology Evolution of Australian Biota New Revised Edition Kerri Humphreys

2 Contents Use the table of contents to record your progress through this book. As you complete each topic, write the date completed, then tick one of the three remaining columns to guide your revision for later. The column headers use the following codes:?? = Don t understand this very well at all. RR = Need to revise this. OK = Know this. Topic Page Date done?? RR OK Topic Page Introduction 1 24 Changing Distribution of 42 Australian Species Verbs To Watch 1 25 Bettongs in Australia 43 1 Assumed Knowledge 2 26 Tasmanian Devils in Australia 45 2 Plate Tectonics 3 27 Theories to Account for 46 Changing Distribution 3 Matching Continental Margins 4 28 Charles Darwin and Australia 47 4 Mid-Ocean Ridges and 6 29 Huxley-Wilberforce Debate 48 Spreading Zones 5 Australia Moves North 7 3 Mitosis 49 6 Fossils and Gondwana 8 31 Meiosis 51 7 Glossopteris and 9 32 Comparing Meiosis and 53 Gangamopteris Mitosis 8 Gondwanan Mammals Internal and External 54 Fertilisation 9 Present-day Gondwanan Fertilisation in Plants 55 Organisms 1 The Platypus Structure of a Flower Extinct and Extant Australian Pollination in Australian Plants 59 Species 12 Variation in a Species 2 37 Seed Dispersal in Australian 61 Plants 13 Variation in Magpies Banksias Variation in Koalas Asexual Reproduction in 65 Australian Plants 15 Timeline for Australia 25 4 Fertilisation in Australian Timeline for the Cainozoic Era Survival of Young in Australian Australian Fossil Sites Kingfishers the Laughing 69 Kookaburra 18 Play Inside Evolution in Australia Asexual Reproduction in 19 Megafauna Palaeontology and Distribution 71 2 Case Study Fossils and Current Human Activities 73 Australian Life Forms 21 Present Australian Biomes Biodiversity Changing Environments in 38 Topic Test 77 Australia 23 Acacia in Australia 4 Answers 81 Index 14 7 Date done?? RR OK 211 First published 24 Revised Edition 211 Bag 723 Marrickville NSW 1475 Australia Tel: (2) Fax: (2) sales@sciencepress.com.au All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording or otherwise, without the prior permission of. ABN

3 Introduction Each book in the Surfing series contains a summary, with occasional more detailed sections, of all the mandatory sections of the syllabus, along with questions and answers. It is envisaged this book will be useful in class for both initial understanding and revision, while the more traditional textbook can remain at home for more detailed analysis. All types of questions multiple choice, short response, structured response and free response are provided. Questions are written in exam style and use the verbs specified by the Board of Studies so that you will become familiar with the concepts of the topic and answering questions in the required way. Answers to all questions are included. A topic test at the end of the book contains an extensive set of summary questions, including multiple choice and free response questions. These cover every aspect of the topic, and are useful for revision and exam practice. Marking guidelines are supplied where appropriate. Verbs To Watch account, account for State reasons for, report on, give an account of, narrate a series of events or transactions. analyse Identify components and the relation ships among them, draw out and relate implications. apply Use, utilise, employ in a particular situation. appreciate Make a judgement about the value of something. assess Make a judgement of value, quality, outcomes, results or size. calculate Determine from given facts, figures or information. clarify Make clear or plain. classify Arrange into classes, groups or categories. compare Show how things are similar or different. construct Make, build, put together items or arguments. contrast Show how things are different or opposite. critically (analyse/evaluate) Add a degree or level of accuracy, depth, knowledge and under standing, logic, questioning, reflection and quality to an analysis or evaluation. deduce Draw conclusions. define State the meaning of and identify essential qualities. demonstrate Show by example. describe Provide characteristics and features. discuss Identify issues and provide points for and against. distinguish Recognise or note/indicate as being distinct or different from, note difference between things. evaluate Make a judgement based on criteria. examine Inquire into. explain Relate cause and effect, make the relationship between things evident, provide why and/or how. extract Choose relevant and/or appropriate details. extrapolate Infer from what is known. identify Recognise and name. interpret Draw meaning from. investigate Plan, inquire into and draw conclusions about. justify Support an argument or conclusion. outline Sketch in general terms; indicate the main features. predict Suggest what may happen based on available information. propose Put forward a point of view, idea, argument, suggestion etc for consid eration or action. recall Present remembered ideas, facts or experiences. recommend Provide reasons in favour. recount Retell a series of events. summarise Express concisely the relevant details. synthesise Put together various elements to make a whole. 1 Evolution of Australian Biota

4 1 Assumed Knowledge 1. Draw a circle diagram to show the inner structure of the Earth. 2. The diagram shows the lithosphere and the layers inside the Earth. Crust Crust 8 to 75 km Mantle Mantle Iron core Layers based on chemical properties Figure 1.1 Lithosphere. Lithosphere 1 to 2 km Asthenosphere 35 to 5 km Mesosphere Rigid lithosphere Plastic asthenosphere Solid mesosphere Liquid outer core 515 km Solid inner core Layers based on physical properties Define the lithosphere. 3. Identify the areas of evidence that suggest crustal s move over time. 4. Outline the fundamental process responsible for crustal motion. 5. Explain how Earthquakes relate to boundaries. 6. Explain how volcanoes relate to boundaries. 7. Figure 1.2 shows the zone of life on Earth. The upper limit of the biosphere is about 12 kilometres above the Earth s surface where air currents carry airborne spores and pollen. From this diagram identify two extreme areas where life if found. 8. Define a fossil. 9. Define natural selection. 1. Use an example to show how present-day organisms have developed from different organisms in the distant past. 11. Describe a new technology that has assisted in increasing our understanding of the evolution of living things. 12. List the major stages in the evolution of living things from organic molecules to multicellular organisms. 13. Use an example to evaluate how the fossil record has increased our ideas about the history of life on Earth. 14. Outline the difference between monotreme, marsupial and placental mammals. 15. Outline Charles Darwin s contribution to evolution. 16. Define mitosis. 17. What is the role of cell division? 18. What is cytokinesis? 19. Describe a difference between mitosis in plant cells and mitosis in animal cells. 2. Where does mitosis occur in plants? 21. Why is mitosis important in asexually reproducing organisms? 22. What is fertilisation? 23. Some animals have both male and female organs on the same body, e.g. tapeworms. What is the name given to animals with both sexes on the same body? 24. What is meiosis? 25. What is pollination? 26. Figure 1.3 shows a cross-section of a flower. I G H A J B C D F Figure 1.3 Parts of a flower. Identify each part of the flower. 27. What is a seed? 28. Distinguish between asexual and sexual reproduction. E Elevation (m) Airborne bacteria, some birds and other organisms Sea level Isolated communities at oceanic ridges; energy obtained from heat and chemical reactions Most of the biosphere is within this band Trench A few scattered bottom-living animals Upper limit of land animals Upper limit of human habitation Bacteria down to several thousand metres Highest mountains Upper limit of most plants Upper limit of agriculture Figure 1.2 Biosphere. Evolution of Australian Biota 2

5 2 Plate Tectonics Plate tectonics is the study of the movement of crustal s. The lithosphere consists of the crust and the upper mantle and is divided into several major s. Plate tectonics provides the evidence that Australia was once part of an ancient super continent. In 1911, Alfred Wegener ( ), a meteorologist who was very interested in meteorology and climatology and made several trips to Greenland studying air currents, became interested in the fossils found on opposite sides of the Atlantic Ocean. There were many identical plants and animals separated by the ocean. The current view of the time held that there had once been a land bridge but it had sunk into the ocean. Wegener looked at the coastline of Africa and South America and the idea arose that the two continents had once been connected. He formed his hypothesis that the continents had once been joined and had since drifted apart, but he knew he needed to collect a large amount of supporting evidence. To support his hypothesis, Wegener studied the rock formations on either side of the Atlantic and found that the Scottish Highlands matched with the Appalachian mountains of eastern North America and the rock strata of the Santa Catarina system in Brazil matched the Karroo system in South Africa. He also looked at the palaeoclimate of old rock formations and found that there were fossils of tropical plants on Spitsbergen, an island in the Arctic circle. This showed that the ancient climate was totally different from the climate today. In 1915 Wegener proposed that the continents had been united into one landmass called Pangaea. He suggested that Pangaea broke apart and the continents drifted apart to their present positions. For this reason his hypothesis was called the continental drift hypothesis. Wegener was not the first person to suggest that the continents had once been joined together. As soon as maps of Africa and South America had been drawn, many scientists noticed that the outlines of the two continents fitted together. However, he was the first to carry out a large systematic study to show that rock types, rock formations and fossils also matched as well as the coastal outline. Many people opposed Wegener s theory as he had no convincing mechanism for the movement of the continents. His hypothesis was supported by Arthur Holmes ( ) who proposed that convection currents in the upper mantle moved the continents. However, it was not until the 195s when scientists began investigating the topography of the ocean floor that the theory of continental drift was revived. Data collected about seismic characteristics, earthquakes, magnetic characteristics, volcanic formations, rock ages and types have led to the theory of tectonics which varies from Wegener s idea of continents ploughing through ocean floors to the theory that oceans and continents form s which move over the asthenosphere. The asthenosphere is the zone below the lithosphere, between 7-2 km below the surface where the material is less solid and has a plastic flow so that the s can move over this more yielding layer. African Eurasian Australian -Indian Antarctic Figure 2.1 Earth s crustal s. For You to Do Pacific North American South American 1. What is tectonics? 2. Outline the observations that led Alfred Wegener to form his hypothesis of continental drift. 3. Discuss the evidence Wegener found to support his hypothesis. 4. What was Pangaea? 5. Explain why Wegener s hypothesis was called the continental drift hypothesis. 6. Why was Holmes hypothesis of convection currents in the upper mantle important in supporting Wegener s hypothesis of continental drift? 7. Outline why Wegener s theory was revised in the 195s. 8. How is modern tectonics different to Wegener s theory of continental drift? 9. What is the asthenosphere? 1. How is the asthenosphere involved in tectonics? 11. Coal deposits, which are the fossilised remains of tropical plants, have been found in Antarctica. What conclusion can be drawn from this evidence? 12. Suggest a reason why Wegener s theory of continental drift was not readily accepted when first proposed. 3 Evolution of Australian Biota