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href="../2852/option-b-biotechnology.html"><i class="fa fa-fw fa-caret-right"></i> Option B - Biotechnology</a></li><li><a href="../2853/option-c-ecology.html"><i class="fa fa-fw fa-caret-right"></i> Option C - Ecology</a></li><li><a href="../2854/option-d-human-physiology.html"><i class="fa fa-fw fa-caret-right"></i> Option D Human physiology</a></li></ul><div class="pull-right"><a class="sidenav-expand" title="Expand all" href="#"><i class="fa fa-plus-circle"></i></a> <a class="sidenav-compress" title="Compress all" href="#"><i class="fa fa-minus-circle"></i></a></div></h4><ul class="side-nav level-0"><li class="expanded parent selected"><label style="padding-left: 0px"><i class="fa fa-fw"></i><a href="evidence-for-evolution-51-.html">Evidence for evolution 5.1 </a></label></li><li class=""><label style="padding-left: 0px"><i class="fa fa-fw"></i><a href="../800/natural-selection-52.html">Natural selection 5.2</a></label></li><li class=""><label style="padding-left: 0px"><i class="fa fa-fw"></i><a href="../801/classification-of-biodiversity-53-.html">Classification of biodiversity 5.3 </a></label></li><li class=""><label style="padding-left: 0px"><i class="fa fa-fw"></i><a href="../802/cladistics-54.html">Cladistics 5.4</a></label></li></ul></div> <div class="hidden-xs hidden-sm"> <button class="btn btn-default btn-block text-xs-center" data-toggle="modal" data-target="#modal-feedback" style="margin-bottom: 10px"><i class="fa fa-send"></i> Feedback</button> </div> </div> <div class="col-md-9" id="main-column"> <h1 class="page_title"> Evidence for evolution 5.1 <a href="#" class="mark-page-favorite pull-right" data-pid="799" title="Mark as favorite" onclick="return false;"><i class="fa fa-star-o"></i></a> </h1> <ol class="breadcrumb"> <li><a href="../../../biology.html"><i class="fa fa-home"></i></a><i class="fa fa-fw fa-chevron-right divider"></i></li><li><a href="../467/05-evolution-.html">05 Evolution </a><i class="fa fa-fw fa-chevron-right divider"></i></li><li><span class="gray">Evidence for evolution 5.1 </span></li> <span class="pull-right" style="color: #555" title="Suggested study time: 30 minutes"><i class="fa fa-clock-o"></i> 30'</span> </ol> <article id="main-article"> <div class="intro-card" readonly="false"><img class="intro-image" readonly="true" src="../../images/05_evolution/red_bird_unsplash.png" style="width: 602px; height: 534px;"> <div class="content" readonly="true"> <div class="text">There are different types of evidence which support the theory of evolution, from fossils to selective breeding. This topic covers a range of evidence and some of the concepts related to inheritance, natural selection and evolution. </div> </div> </div> <div class="panel panel-turquoise"> <div class="panel-heading"><a class="expander pull-right" href="#"><span class="fa fa-plus"></span></a> <div> <p>Key concepts</p> </div> </div> <div class="panel-body"> <div> <p>Learn and test your biological vocabulary for 5.1 Evidence for evolution using these flashcards.</p> <p style="text-align: center"><iframe height="500" src="https://quizlet.com/419004108/flashcards/embed?i=xxmo&x=1jj1" style="border:0" width="100%"></iframe></p> </div> </div> <div class="panel-footer"> <div> <p>text</p> </div> </div> </div> <div class="panel panel-default"> <div class="panel-footer"> <div> <p>text</p> </div> </div> </div> <div class="panel panel-yellow"> <div class="panel-heading"><a class="expander pull-right" href="#"><span class="fa fa-plus"></span></a> <div> <p>Essentials</p> </div> </div> <div class="panel-body"> <div> <p>These slides summarise the essential understanding and skills in this topic. <br> They contain short explanations in text and images - good revision for all students.</p> <p>Read the slides and look up any words or details you find difficult to understand.</p> <div id="carousel-122" class="dynamic-gallery carousel slide" data-id="122"><div class="carousel-inner" role="listbox"><div class="item active"><a class="fancy" href="../../../std-galleries/5-122/img0.jpg" data-fancybox="gallery-122" title="" data-caption=""><img alt="" src="../../../std-galleries/5-122/img0.jpg"></a></div><div class="item "><a class="fancy" href="../../../std-galleries/5-122/img1.jpg" data-fancybox="gallery-122" title="" data-caption=""><img alt="" src="../../../std-galleries/5-122/img1.jpg"></a></div><div class="item "><a class="fancy" href="../../../std-galleries/5-122/img2.jpg" data-fancybox="gallery-122" title="" data-caption=""><img alt="" src="../../../std-galleries/5-122/img2.jpg"></a></div><div class="item "><a class="fancy" href="../../../std-galleries/5-122/img3.jpg" data-fancybox="gallery-122" title="" data-caption=""><img alt="" src="../../../std-galleries/5-122/img3.jpg"></a></div><div class="item "><a class="fancy" href="../../../std-galleries/5-122/img4.jpg" data-fancybox="gallery-122" title="" data-caption=""><img alt="" src="../../../std-galleries/5-122/img4.jpg"></a></div></div><a class="left carousel-control" href="#carousel-122" role="button" data-slide="prev"><i class="fa fa-fw fa-chevron-left"></i></a><a class="right carousel-control" href="#carousel-122" role="button" data-slide="next"><i class="fa fa-fw fa-chevron-right"></i></a></div><ol class="std-carousel-indicators"><li data-index="0"><img title="Click to view" src="../../../std-galleries/5-122/img0-thumb128.jpg"><li><li data-index="1"><img title="Click to view" src="../../../std-galleries/5-122/img1-thumb128.jpg"><li><li data-index="2"><img title="Click to view" src="../../../std-galleries/5-122/img2-thumb128.jpg"><li><li data-index="3"><img title="Click to view" src="../../../std-galleries/5-122/img3-thumb128.jpg"><li><li data-index="4"><img title="Click to view" src="../../../std-galleries/5-122/img4-thumb128.jpg"><li></li></ol> </div> </div> <div class="panel-footer"> <div> <p>These slides summarise the essential understanding and skills in this topic. <br> They contain short explanations in text and images - great revision.</p> <p>Read the slides and look up any words or details you find difficult to understand.</p> <div id="carousel-210" class="dynamic-gallery carousel slide" data-id="210"><div class="carousel-inner" role="listbox"><div class="item active"><a class="fancy" href="../../../std-galleries/5-210/112movement-1.jpg" data-fancybox="gallery-210" title="" data-caption=""><img alt="" src="../../../std-galleries/5-210/112movement-1.jpg"></a></div><div class="item "><a class="fancy" href="../../../std-galleries/5-210/112movement-2.jpg" data-fancybox="gallery-210" title="" data-caption=""><img alt="" src="../../../std-galleries/5-210/112movement-2.jpg"></a></div><div class="item "><a class="fancy" href="../../../std-galleries/5-210/112movement-3.jpg" data-fancybox="gallery-210" title="" data-caption=""><img alt="" src="../../../std-galleries/5-210/112movement-3.jpg"></a></div><div class="item "><a class="fancy" href="../../../std-galleries/5-210/112movement-4.jpg" data-fancybox="gallery-210" title="" data-caption=""><img alt="" src="../../../std-galleries/5-210/112movement-4.jpg"></a></div><div class="item "><a class="fancy" href="../../../std-galleries/5-210/112movement-5.jpg" data-fancybox="gallery-210" title="" data-caption=""><img alt="" src="../../../std-galleries/5-210/112movement-5.jpg"></a></div></div><a class="left carousel-control" href="#carousel-210" role="button" data-slide="prev"><i class="fa fa-fw fa-chevron-left"></i></a><a class="right carousel-control" href="#carousel-210" role="button" data-slide="next"><i class="fa fa-fw fa-chevron-right"></i></a></div><ol class="std-carousel-indicators"><li data-index="0"><img title="Click to view" src="../../../std-galleries/5-210/112movement-1-thumb128.jpg"><li><li data-index="1"><img title="Click to view" src="../../../std-galleries/5-210/112movement-2-thumb128.jpg"><li><li data-index="2"><img title="Click to view" src="../../../std-galleries/5-210/112movement-3-thumb128.jpg"><li><li data-index="3"><img title="Click to view" src="../../../std-galleries/5-210/112movement-4-thumb128.jpg"><li><li data-index="4"><img title="Click to view" src="../../../std-galleries/5-210/112movement-5-thumb128.jpg"><li></li></ol> </div> </div> </div> <div class="panel panel-violet"> <div class="panel-heading"><a class="expander pull-right" href="#"><span class="fa fa-plus"></span></a> <div> <p>Summary</p> </div> </div> <div class="panel-body"> <div> <h3>Revision summary list for 5.1 Evidence for evolution</h3> <ul> <li>A change in the heritable characteristics of a species is evolution.<img alt="" class="Left" height="80" src="../../../ib/biology/images/flickr_cc_commercial_ok/05_evolution/squiggle_bird_huge_beak.png" style="float: right;" width="123"></li> <li>Evidence for evolution comes from <ul> <li>the fossil record.</li> <li>Selective breeding of domesticated animals</li> <li>"Adaptive radiation" can explain similar structures with different functions.</li> <li>Isolated populations can produce separate species by divergent evolution.</li> <li>Continuous variation across the geographical range of related populations matches the concept of gradual divergence.</li> </ul> </li> </ul> <div class="yellowBg"> <p><u>Skills</u> (can you ....)</p> <ul> <li>Describe how the dark bark leads to the development of melanistic insects in polluted areas.</li> <li>Compare and contrast the pentadactyl limb of mammals, birds, amphibians and reptiles.</li> <li>Describe how each limb structure is adapted to each different method of locomotion.</li> </ul> </div> <hr class="hidden-separator"> <h3>Mindmaps</h3> <p>These diagram summaries cover the main sections of topic 4.3 Carbon cycle.<br> Study them and draw your own list or concept map, from memory if you can.</p> <div id="carousel-123" class="dynamic-gallery carousel slide" data-id="123"><div class="carousel-inner" role="listbox"><div class="item active"><a class="fancy" href="../../../std-galleries/5-123/51evidenceevolspiderlist.png" data-fancybox="gallery-123" title="" data-caption=""><img alt="" src="../../../std-galleries/5-123/51evidenceevolspiderlist.png"></a></div><div class="item "><a class="fancy" href="../../../std-galleries/5-123/51evidenceevolspidersimple.png" data-fancybox="gallery-123" title="" data-caption=""><img alt="" src="../../../std-galleries/5-123/51evidenceevolspidersimple.png"></a></div><div class="item "><a class="fancy" href="../../../std-galleries/5-123/51evidenceevolspiderdetaiiled.png" data-fancybox="gallery-123" title="" data-caption=""><img alt="" src="../../../std-galleries/5-123/51evidenceevolspiderdetaiiled.png"></a></div></div><a class="left carousel-control" href="#carousel-123" role="button" data-slide="prev"><i class="fa fa-fw fa-chevron-left"></i></a><a class="right carousel-control" href="#carousel-123" role="button" data-slide="next"><i class="fa fa-fw fa-chevron-right"></i></a></div><ol class="std-carousel-indicators"><li data-index="0"><img title="Click to view" src="../../../std-galleries/5-123/51evidenceevolspiderlist-thumb128.jpg"><li><li data-index="1"><img title="Click to view" src="../../../std-galleries/5-123/51evidenceevolspidersimple-thumb128.jpg"><li><li data-index="2"><img title="Click to view" src="../../../std-galleries/5-123/51evidenceevolspiderdetaiiled-thumb128.jpg"><li></li></ol> </div> </div> <div class="panel-footer"> <div> <p>text</p> </div> </div> </div> <div class="panel panel-default"> <div class="panel-heading"><a class="expander pull-right" href="#"><span class="fa fa-plus"></span></a> <div> <p>Exam style questions</p> </div> </div> <div class="panel-body"> <div> <h3>Question about pentadactyl limbs as evidence of evolution</h3> <div> <p>The question below, requires an understanding of the structure of the pentadactyl limb and the differences and adaptations which can be found in different animals. In this case the examples are birds and humans.</p> <p>Answer the question on paper and then compare your answer to the model answer.</p> <div class="yellowBg"> <p>This diagram shows pentadactyl limbs in Birds and Humans</p> <p><img alt="" src="../../images/05_evolution/pentadactyl_diagram_simplified.png" style="width: 713px; height: 367px; border-width: 1px; border-style: solid;"></p> <p><strong>Compare and contrast the pentadactyl limb of mammals and birds. [4]</strong></p> <ul> <li><em>Include similarities in structure</em></li> <li><em>Mention differences in specific elements</em></li> </ul> <p><strong>....................................................................................... ............................................................................ </strong></p> <p><strong>....................................................................................... ............................................................................ </strong></p> <p><strong>....................................................................................... ............................................................................ </strong></p> <p><strong>....................................................................................... ............................................................................ </strong></p> <p><strong>Describe how the structure of the wing and hand is adapted to each different function [2]</strong></p> <ul> <li>Try to link structure and function in each point of your answers?</li> </ul> <p><strong>....................................................................................... ............................................................................ </strong></p> <strong>....................................................................................... ............................................................................ </strong> <p><strong>Explain how the existence of pentadactyl limbs in birds and mammals provides evidence supporting the theory of evolution. [3]</strong></p> <p><strong>....................................................................................... ............................................................................ </strong></p> <p><strong>....................................................................................... ............................................................................ </strong></p> <p><strong>....................................................................................... ............................................................................ </strong></p> </div> </div> <p>Click the + icon to see a model answer.</p> <button class="btn btn-xs bg-turquoise showhider"><i class="fa fa-fw fa-plus"></i></button><section class="hiddenbox hidden"> <h3>Model answer</h3> <p>The skill of this answer is to ensure that the points make logical connections between the two species.</p> <div class="yellowBg"> <p><strong>Compare and contrast the pentadactyl limb of mammals and birds. [4]</strong></p> <p><span style="color:#FF0000;">Similarities</span></p> <ul> <li><span style="color:#FF0000;">The bird wing and the human arm both have a humerus, ulna and a radius bone.</span></li> <li><span style="color:#FF0000;">Both limbs also have several wrist bones</span></li> <li><span style="color:#FF0000;">They are an example of homologous structures - evolving from a single origin.</span></li> </ul> <p><span style="color:#FF0000;">Differences</span></p> <ul> <li><span style="color:#FF0000;">There are only three "finger bones" in the bird wing and five in the human hand.</span></li> <li><span style="color:#FF0000;">The finger bones are longer in the bird wing than in the human hand.</span></li> </ul> <p><strong>Describe how the structure of the wing and hand is adapted to each different function. [2]</strong></p> <p>The skill in this answer is to link a structure to it's function</p> <ul> <li><span style="color:#FF0000;">The wrist bones of birds have long shapes, allowing the attachment of feathers.</span></li> <li><span style="color:#FF0000;">The position of the thumb opposite the other fingers on the human hand allow it to hold tools</span></li> </ul> <p><strong>Explain how the existence of these structures in birds and mammals provides evidence supporting the theory of evolution. [3]</strong></p> <p>This answer requires knowledge beyond the data provided.</p> <p><span style="color:#FF0000;">The pentadactyl limb is found in Birds Mammals as well as reptiles and amphibians </span></p> <p><span style="color:#FF0000;">They all share the same organisation of bones even though these animals use a wide variety of methods of locomotion. This is known as 'adaptive radiation'.</span></p> <p><span style="color:#FF0000;">The simplest explanation of the existence of this bone arrangement in so many different animals is that it evolved once in history in a common ancestor of all the animals. These animals have since evolved by divergent evolution to use the structures in a variety of ways.</span></p> <p><span style="color:#FF0000;">It would be very unlikely that two separate evolutionary processes would arrive at the same structure as complex as a pentadactyl limb.</span></p> </div> </section> <div class="panel panel-has-colored-body panel-expandable panel-has-border panel-default"> <div class="panel-heading"><a class="expander pull-right" href="#"><span class="fa fa-plus"></span></a> <div> <p>Extra exam question about adaptive radiation (evolution). Click to open it .</p> </div> </div> <div class="panel-body"> <div> <p>The question below, requires an understanding of adaptive radiation, but also knowledge of the finches of the Galapagos islands. Explaining how the finches provides evidence for the process of adaptive radiation is worth thinking through and practising.</p> <p>Answer the question on paper and then compare your answer to the model answer.</p> <div class="yellowBg"> <p>The diagram below, drawn by Darwin, illustrates the size and shape of finch species in the Galapagos islands.</p> <p style="text-align: center;"><strong><img alt="" src="../../images/05_evolution/darwin_finches_drawings.jpg" style="width: 200px; height: 156px;"></strong></p> <p><strong>Explain how the shape of beaks in Galapagos finches provides evidence for adaptive radiation</strong>. <strong>[4]</strong></p> <p><strong>....................................................................................... ............................................................................ </strong></p> <p><strong>....................................................................................... ............................................................................ </strong></p> <p><strong>....................................................................................... ............................................................................ </strong></p> <p><strong>....................................................................................... ............................................................................ </strong></p> <p><strong>....................................................................................... ............................................................................ </strong></p> </div> <button class="btn btn-xs bg-turquoise showhider"><i class="fa fa-fw fa-plus"></i></button><section class="hiddenbox hidden"> <h3>Model answer</h3> <div class="yellowBg"> <p><strong>Explain how the shape of beaks in Galapagos finches provides evidence for adaptive radiation. [4]</strong></p> <p><span style="color:#FF0000;">Adaptive radiation is the development of one ancestor species into several different forms as each one separately adapts to the environment in each of the different, new, unoccupied ecological niches.</span></p> <p><span style="color:#FF0000;">Darwin discovered many different forms of closely related Galapagos finches on the islands of the archipelago, the Galapagos islands..</span></p> <p><span style="color:#FF0000;"> The size and shape of their beaks which was most noticeably different and all these different forms of beak supported the idea of adaptive radiation.</span></p> <p><span style="color:#FF0000;">Each species had had separately evolved from a single species of ancestor finch. Each island having different environmental conditions had resulted in the finches on that island evolving in slightly different ways to have beaks of different shapes.</span></p> </div> </section> </div> </div> <div class="panel-footer"> <div> <p>text</p> </div> </div> </div> </div> </div> <div class="panel panel-has-colored-body panel-expandable panel-has-border panel-default"> <div class="panel-heading"> <div> <p>Extra exam question on speciation - - - click to open.</p> </div> </div> <div class="panel-body"> <div> <p>Speciation is the evolution of two distinct species from a common ancestor.</p> <p>Answer the question on paper and then compare your answer to the model answer.</p> <p><span style="font-family:arial,helvetica,sans-serif;"><b><span lang="EN-GB" style="font-size: 11pt; line-height: 107%;">Outline how one population of a species can evolve into two separate species. (5 marks). </span></b></span></p> <div class="yellowBg"> <hr> <hr> <hr> <hr><em>Hint: Outline requires the main points. The word "speciation" is not in the question and so will gain credit.</em></div> Click on the "+" icon to see a model answer. <button class="btn btn-xs bg-turquoise showhider"><i class="fa fa-fw fa-plus"></i></button><section class="hiddenbox hidden"> <h3>Model answer</h3> <p>Examples of speciation may help you to answer the question.</p> <div class="yellowBg"> <p><strong>Outline how one population of a species can evolve into two separate species. (5 marks). </strong></p> <ul> <li style="margin-left: 18pt;"><span style="color:#FF0000;">Speciation is the evolution of two or more species from a common ancestor.</span></li> <li style="margin-left: 18pt;"><span style="color:#FF0000;">Speciation occurs when two populations are isolated from each other.</span></li> <li style="margin-left: 18pt;"><span style="color:#FF0000;">By geographic or behavioural factors.</span></li> <li style="margin-left: 18pt;"><span style="color:#FF0000;">The two populations are not able to interbreed.</span></li> <li style="margin-left: 18pt;"><span style="color:#FF0000;">Different selection pressures in the different environments can favour different characteristics.</span></li> <li style="margin-left: 18pt;"><span style="color:#FF0000;">The heritable characteristics of the two populations diverge as the genomes change.</span></li> <li style="margin-left: 18pt;"><span style="color:#FF0000;">Speciation can then occur when the two species evolve different traits and have sufficient variation to be considered as different species.</span></li> </ul> <p style="margin-left: 18pt;"><em>Examiner hint: Speciation requires isolation and different selection pressures as if the two groups interbreed they will not become separate species.</em></p> </div> </section> </div> </div> </div> <div class="panel-footer"> <div> <p>text</p> </div> </div> </div> <div class="panel panel-green"> <div class="panel-heading"><a class="expander pull-right" href="#"><span class="fa fa-plus"></span></a> <div> <p>Test yourself</p> </div> </div> <div class="panel-body"> <div> <h3>Multiple choice questions</h3> <p>This is a self marking quiz containing questions covering the topic outlined above.<br> Try the questions to check your understanding.</p> <br><a class="btn btn-primary btn-block text-center" data-toggle="modal" href="#2225ae6d"><i class="fa fa-play"></i> START QUIZ!</a><div class="modal fade modal-slide-quiz" id="2225ae6d"> <div class="modal-dialog" style="width: 95vw; max-width: 960px"> <div class="modal-content"> <div class="modal-header slide-quiz-title"> <h4 class="modal-title" style="width: 100%;"> 5.1 Evidence for evolution (1) <strong class="q-number pull-right"> <span class="counter">1</span>/<span class="total">1</span> </strong> </h4> </div> <div class="modal-body p-xs-3"> <div class="slide-quiz" data-stats="5-339-799" style="opacity: 0"> <div class="exercise shadow-bottom"><div class="q-question"><p>Which of the following statements is <u><strong>not</strong></u> true about Evolution?</p></div><div class="q-answer"><p><label class="radio"><input class="c" type="radio"> It is learned by animals during their lifetime.</label></p><p><label class="radio"><input type="radio"> It happens at the species level.</label></p><p><label class="radio"><input type="radio"> It's a gradual cumulative change.</label></p><p><label class="radio"><input type="radio"> It concerns characteristics which can be inherited.</label></p></div><div class="q-explanation"><p>"A change in the heritable characteristics of a species" is evolution. <br>Most frequently this is a gradual cumulative change.</p><p>Changes to individual organisms during their lifetime are not evolution, as the change has to be heritable.<br>Evolution occurs a the species level because individuals survive or die which changes the composition of the members of the species.</p></div><div class="slide-q-actions"><button class="btn btn-default btn-sm btn-xs-block text-xs-center check"><i class="fa fa-check-square-o"></i> Check</button></div></div><div class="exercise shadow-bottom"><div class="q-question"><p>Which of the points below provide evidence in support of evolution?</p><ol start="1" style="list-style-type: upper-roman;"><li><p>The fossil record.</p></li><li><p>Selective breeding of food crops.</p></li><li><p>The wings of birds and bats</p></li><li><p>Radiation studies</p></li></ol></div><div class="q-answer"><p><label class="radio"><input class="c" type="radio"> I, and II</label></p><p><label class="radio"><input type="radio"> All of the points</label></p><p><label class="radio"><input type="radio"> I and IV</label></p><p><label class="radio"><input type="radio"> I and III</label></p></div><div class="q-explanation"><p>Evidence for evolution in this list comes from;</p><ul><li>The fossil record.</li><li>Selective breeding of food crops and domesticated animals.</li></ul></div><div class="slide-q-actions"><button class="btn btn-default btn-sm btn-xs-block text-xs-center check"><i class="fa fa-check-square-o"></i> Check</button></div></div><div class="exercise shadow-bottom"><div class="q-question"><p>What might be expected to happen if two populations of a species of snail are separated by a river which has very different environmental conditions on each bank, for example a woodland and a golf course?</p><p><img alt="" src="../../images/05_evolution/snail_golf_woodland.png" style="width: 400px; height: 229px;"></p></div><div class="q-answer"><p><label class="radio"><input class="c" type="radio"> Divergent evolution.</label></p><p><label class="radio"><input type="radio"> Interbreeding of the two population.</label></p><p><label class="radio"><input type="radio"> One population will become better adapted to the environment.</label></p><p><label class="radio"><input type="radio"> Convergent evolution.</label></p></div><div class="q-explanation"><p>If the are different selection pressures in the two environments, then snails will be affected by different natural selection. This is divergent selection.</p></div><div class="slide-q-actions"><button class="btn btn-default btn-sm btn-xs-block text-xs-center check"><i class="fa fa-check-square-o"></i> Check</button></div></div><div class="exercise shadow-bottom"><div class="q-question"><p>Lake Malawi has a surface area of almost 30 000 km<sup>2</sup> and is home to 1000 species of Cichlid fish.</p><p style="text-align: center;"><img alt="" src="../../images/05_evolution/chiclids_malawi.png" style="width: 400px; height: 248px;"></p><p>The diagram of Cichlid fish varieties illustrates a continuous variation in their features across the geographical range of the lake.</p><p>It is understood that all but five species are descendants of a single original colonist species?</p><p>What is the name of the process which forms this sort diversity?</p></div><div class="q-answer"><p><label class="radio"><input type="radio"> Evolution.</label></p><p><label class="radio"><input type="radio"> Gradual production of new species.</label></p><p><label class="radio"><input class="c" type="radio"> Adaptive radiation.</label></p><p><label class="radio"><input type="radio"> Natural selection.</label></p></div><div class="q-explanation"><p>Continuous variation across the geographical range of related populations matches the concept of gradual divergence.</p></div><div class="slide-q-actions"><button class="btn btn-default btn-sm btn-xs-block text-xs-center check"><i class="fa fa-check-square-o"></i> Check</button></div></div><div class="exercise shadow-bottom"><div class="q-question"><p>The image below shows adaptations in the wings of modern insects.</p><p><img alt="" src="../../images/05_evolution/homologous_wing_parts.png" style="width: 500px; height: 193px;"></p><p>There is evidence that ancestors of all these insects had two pairs of wings.</p><p>What is the biological term for structures like these?</p></div><div class="q-answer"><p><label class="radio"><input type="radio"> Equivalent.</label></p><p><label class="radio"><input class="c" type="radio"> Homologous.</label><label class="radio"></label></p><p><label class="radio"><input type="radio"> Vestigial</label></p><p><label class="radio"><input type="radio"> Equivalent</label></p></div><div class="q-explanation"><p>All the insects share the feature of having 2 pairs of 'wing-like' structures although there are differences in each animal.</p>This suggests that they all shared a common ancestor, with 2 pairs of wings.</div><div class="slide-q-actions"><button class="btn btn-default btn-sm btn-xs-block text-xs-center check"><i class="fa fa-check-square-o"></i> Check</button></div></div><div class="exercise shadow-bottom"><div class="q-question"><p>What is the best description of selective breeding?</p></div><div class="q-answer"><p><label class="radio"><input type="radio"> A farmer selects sheep with the highest quality wool at a market.</label></p><p><label class="radio"><input type="radio"> A zoologist in a safari park puts animals together for breeding to increase genetic diversity.</label></p><p><label class="radio"><input class="c" type="radio"> A dog breeder selects the animals with preferred features for his breeding programme.</label></p><p><label class="radio"><input type="radio"> A pet owner keeps carefully selected aquarium fish so there are no predators in the tank.</label></p></div><div class="q-explanation"><p>Selective breeding provides evidence for evolution because it shows that when a breeder chooses the animals for the breeding programme which have specific features, the offspring have more of these features.</p></div><div class="slide-q-actions"><button class="btn btn-default btn-sm btn-xs-block text-xs-center check"><i class="fa fa-check-square-o"></i> Check</button></div></div><div class="exercise shadow-bottom"><div class="q-question"><p>What natural process causes the increase in frequence of the melanistic form of the Peppered moth if pollution causes the vegetation it lives on to be covered in smoke and become darker?</p></div><div class="q-answer"><p><label class="radio"><input type="radio"> Selective breeding</label></p><p><label class="radio"><input type="radio"> Adaptive radiation</label></p><p><label class="radio"><input class="c" type="radio"> Natural selection</label></p><p><label class="radio"><input type="radio"> Disruptive selection</label></p></div><div class="q-explanation"><p>Natural selection causes an increase in the number of dark moths because the birds which eat the moths cannot see the dark forms so easily, as they have better camouflage in polluted environments.</p></div><div class="slide-q-actions"><button class="btn btn-default btn-sm btn-xs-block text-xs-center check"><i class="fa fa-check-square-o"></i> Check</button></div></div> </div> </div> <div class="modal-footer slide-quiz-actions"> <div class=""> <div class="pull-left pull-xs-none mb-xs-3"> <button class="btn btn-default d-xs-none btn-prev"> <i class="fa fa-arrow-left"></i> Prev </button> </div> <div class="pull-right pull-xs-none"> <button class="btn btn-success btn-xs-block text-xs-center btn-results" style="display: none"> <i class="fa fa-bar-chart"></i> Check Results </button> <button class="btn btn-default d-xs-none btn-next"> Next <i class="fa fa-arrow-right"></i> </button> <button class="btn btn-default btn-xs-block text-xs-center btn-close" data-dismiss="modal" style="display: none"> Close </button> </div> </div> </div> </div> </div></div> <hr class="hidden-separator"> <p>This is a second self marking quiz containing different questions covering the topic outlined above in a slightly different way.</p> <br><a class="btn btn-primary btn-block text-center" data-toggle="modal" href="#ec333da3"><i class="fa fa-play"></i> START QUIZ!</a><div class="modal fade modal-slide-quiz" id="ec333da3"> <div class="modal-dialog" style="width: 95vw; max-width: 960px"> <div class="modal-content"> <div class="modal-header slide-quiz-title"> <h4 class="modal-title" style="width: 100%;"> 5.1 Evidence for evolution (2) <strong class="q-number pull-right"> <span class="counter">1</span>/<span class="total">1</span> </strong> </h4> </div> <div class="modal-body p-xs-3"> <div class="slide-quiz" data-stats="5-599-799" style="opacity: 0"> <div class="exercise shadow-bottom"><div class="q-question"><p>Which is the most compelling evidence provided by fossils in support of evolution?</p></div><div class="q-answer"><p><label class="radio"><input type="radio"> They can be dated which shows their origin.</label></p><p><label class="radio"><input type="radio"> They are found in sedimentary rocks.</label></p><p><label class="radio"><input class="c" type="radio"> They document the existence of extinct organisms that show a relationship to present day species.</label></p><p><label class="radio"><input type="radio"> They are extinct species which end an evolutionary line.</label></p></div><div class="q-explanation"><p>All the answers have some relevance but the most compelling is that they document the existence of extinct organisms that show a relationship to present day species, often illustrating the cumulative changes which have occurred.</p></div><div class="slide-q-actions"><button class="btn btn-default btn-sm btn-xs-block text-xs-center check"><i class="fa fa-check-square-o"></i> Check</button></div></div><div class="exercise shadow-bottom"><div class="q-question"><p><span>Which of the following best describes homologous structures?</span></p></div><div class="q-answer"><p><label class="radio"><input type="radio"> They are identical in structure.</label></p><p><label class="radio"><input type="radio"> They are identical in function.</label></p><p><label class="radio"><input class="c" type="radio"> They are derived from single origin in a common ancestor.</label></p><p><label class="radio"><input type="radio"> They are identical in structure and function.</label></p></div><div class="q-explanation"><p>Homologous structures evolved from a common ancestor and have a similar structure but this structure may be modified to adapted to a different function.</p></div><div class="slide-q-actions"><button class="btn btn-default btn-sm btn-xs-block text-xs-center check"><i class="fa fa-check-square-o"></i> Check</button></div></div><div class="exercise shadow-bottom"><div class="q-question"><p>Which of these statements best describes the structure and function of homologous characteristics?</p></div><div class="q-answer"><p><label class="radio"><input type="radio"> Similar in structure and have the same function.</label></p><p><label class="radio"><input type="radio"> Identical in structure and vary in function.</label></p><p><label class="radio"><input class="c" type="radio"> <span data-sheets-formula-bar-text-style="font-size:13px;color:#000000;font-weight:normal;text-decoration:none;font-family:'Arial';font-style:normal;text-decoration-skip-ink:none;">Similar in structure and may vary in function.</span></label></p><p><label class="radio"><input type="radio"> Animal legs, arms, wings and claws are homologous structures.</label></p></div><div class="q-explanation"><p>Homologous structures have a similar structure but not identical structures, and this allows them to adapt to new functions. Legs and arms of animals are sometimes examples of homologous structures but, not always, e.g. insect legs and human legs are not homologous.</p></div><div class="slide-q-actions"><button class="btn btn-default btn-sm btn-xs-block text-xs-center check"><i class="fa fa-check-square-o"></i> Check</button></div></div><div class="exercise shadow-bottom"><div class="q-question"><p>Adaptive radiation is shown by organisms evolving in different environments. What observable patterns does this process lead to?</p></div><div class="q-answer"><p><label class="radio"><input type="radio"> Different types of limbs in organisms.</label></p><p><label class="radio"><input type="radio"> Common features in unrelated species.</label></p><p><label class="radio"><input class="c" type="radio"> A range of different adaptations of a feature in related species.</label></p><p><label class="radio"><input type="radio"> Very similar organisms with different forms of locomotion.</label></p></div><div class="q-explanation"><p>Adaptive radiation occurs when different selection pressures lead to the evolution of a range of different adaptations. This may occur at first in a single species but will eventually be seen in several related species. They may be in different isolated locations or in organisms exploiting different niches in a single environment.</p></div><div class="slide-q-actions"><button class="btn btn-default btn-sm btn-xs-block text-xs-center check"><i class="fa fa-check-square-o"></i> Check</button></div></div><div class="exercise shadow-bottom"><div class="q-question"><p>Which two factors drive the process of adaptive radiation.</p></div><div class="q-answer"><p><label class="radio"><input type="radio"> Random selection of mates in reproduction and different behaviour.</label></p><p><label class="radio"><input type="radio"> Random genetic mutations and new forms of DNA appearing.</label></p><p><label class="radio"><input class="c" type="radio"> Random genetic mutations and different selection pressures.</label></p><p><label class="radio"><input type="radio"> New forms of locomotion and different reproductive behaviour. </label></p></div><div class="q-explanation"><p>Adaptive radiation occurs when different selection pressures lead to the evolution of one or more species which are exploiting different niches in an environment. Mutations bring about new alleles in several genes and different selection pressures in each niche lead to the natural selection to favour different adaptations.</p></div><div class="slide-q-actions"><button class="btn btn-default btn-sm btn-xs-block text-xs-center check"><i class="fa fa-check-square-o"></i> Check</button></div></div><div class="exercise shadow-bottom"><div class="q-question"><p><span data-sheets-formula-bar-text-style="font-size:13px;color:#000000;font-weight:normal;text-decoration:none;font-family:'Arial';font-style:normal;text-decoration-skip-ink:none;">The existence of different breeds of domestic dog is due to which of the following?</span></p></div><div class="q-answer"><p><label class="radio"><input class="c" type="radio"> Artificial selection.</label></p><p><label class="radio"><input type="radio"> A Mutation.</label></p><p><label class="radio"><input type="radio"> Natural selection.</label></p><p><label class="radio"><input type="radio"> Random mating.</label></p></div><div class="q-explanation"><p>Dog breeds are developed by humans artificially selecting certain traits in dogs and breeding only the animals with these desired traits.</p></div><div class="slide-q-actions"><button class="btn btn-default btn-sm btn-xs-block text-xs-center check"><i class="fa fa-check-square-o"></i> Check</button></div></div><div class="exercise shadow-bottom"><div class="q-question"><p>Which of the following best describes evolution?</p></div><div class="q-answer"><p><label class="radio"><input type="radio"> A change in the appearance of a species.</label></p><p><label class="radio"><input class="c" type="radio"> A change in the heritable characteristics of a species over time.</label></p><p><label class="radio"><input type="radio"> The formation of new species.</label></p><p><label class="radio"><input type="radio"> Random changes in the genes of a species.</label></p></div><div class="q-explanation"><p>As evolution occurs, the heritable characteristics (genes) in the gene pool of a species change to those which are the most successful for survival.</p></div><div class="slide-q-actions"><button class="btn btn-default btn-sm btn-xs-block text-xs-center check"><i class="fa fa-check-square-o"></i> Check</button></div></div><div class="exercise shadow-bottom"><div class="q-question"><p>Which of the following must happen to allow two new species to arise from a single species?</p><p>I Separation of the original species into two groups<br>II Interbreeding between the groups<br>III Different mutations in the two groups<br>IV Reproductive isolation between the two groups</p></div><div class="q-answer"><p><label class="radio"><input type="radio"> I only.</label></p><p><label class="radio"><input type="radio"> II and III only.</label></p><p><label class="radio"><input class="c" type="radio"> I, III, IV only.</label></p><p><label class="radio"><input type="radio"> All of the above, I, II, III, and IV.</label></p></div><div class="q-explanation"><p>For two groups of one species to form two species, they must be reproductively isolated, so they cannot interbreed and then different mutations will allow different genetic variation in each of the isolated populations, leading to adaptation to their respective environments and phenotypic differences between the groups.</p></div><div class="slide-q-actions"><button class="btn btn-default btn-sm btn-xs-block text-xs-center check"><i class="fa fa-check-square-o"></i> Check</button></div></div> </div> </div> <div class="modal-footer slide-quiz-actions"> <div class=""> <div class="pull-left pull-xs-none mb-xs-3"> <button class="btn btn-default d-xs-none btn-prev"> <i class="fa fa-arrow-left"></i> Prev </button> </div> <div class="pull-right pull-xs-none"> <button class="btn btn-success btn-xs-block text-xs-center btn-results" style="display: none"> <i class="fa fa-bar-chart"></i> Check Results </button> <button class="btn btn-default d-xs-none btn-next"> Next <i class="fa fa-arrow-right"></i> </button> <button class="btn btn-default btn-xs-block text-xs-center btn-close" data-dismiss="modal" style="display: none"> Close </button> </div> </div> </div> </div> </div></div> <h3>Drag and drop activities</h3> <p>Test your ability to construct biological explanations using the drag and drop questions below.</p> <div class="tib-quiz" data-stats="5-875-799"><p>The acceptance of a scientific theory requires evidence. Fossils are one piece of evidence for the scientific theory of evolution.</p><p style="text-align: center;"><img alt="" src="../../images/richard/topic-3-images/5.1-fossils.jpg" style="width: 250px; height: 119px;"></p><p>Drag and drop the correct word or phrase to outline the evidence for evolution provided by fossils.</p><div class="label label-default q-number">1</div><div class="exercise shadow-bottom"><div class="q-question"><p> </p><p class="gap-drop"> <span class="q-text-draggable draggable" draggable="true">present day</span> <span class="q-text-draggable draggable" draggable="true">long time scales</span> <span class="q-text-draggable draggable" draggable="true">complexity</span> <span class="q-text-draggable draggable" draggable="true">sequences</span> <span class="q-text-draggable draggable" draggable="true">living</span> <span class="q-text-draggable draggable" draggable="true">hundreds of years</span> <span class="q-text-draggable draggable" draggable="true">internal organs</span> <span class="q-text-draggable draggable" draggable="true">hard</span> <span class="q-text-draggable draggable" draggable="true">preserved</span> <span class="q-text-draggable draggable" draggable="true">shells</span> <span class="q-text-draggable draggable" draggable="true">extinct</span> <span class="q-text-draggable draggable" draggable="true">single-celled</span></p></div><div class="q-answer"><p>Fossils are the <input type="text" style="height: auto;" data-c=" preserved"> <span class="review"></span> remains of previously living organisms. Bones and <input type="text" style="height: auto;" data-c="shells"> <span class="review"></span> are commonly fossilised as they are <input type="text" style="height: auto;" data-c="hard"> <span class="review"></span> and durable by nature.</p><p>Fossils provide evidence for evolution in several ways:</p><ol><li>They demonstrate the existence of organisms that are not now <input type="text" style="height: auto;" data-c="living"> <span class="review"></span> .</li><li>Fossil <input type="text" style="height: auto;" data-c="sequences"> <span class="review"></span> show gradual evolution of species.</li><li>Fossils provide evidence of evolution over <input type="text" style="height: auto;" data-c="long time scales"> <span class="review"></span> .</li><li>Fossils of now <input type="text" style="height: auto;" data-c="extinct"> <span class="review"></span> species can be linked to <input type="text" style="height: auto;" data-c="present day"> <span class="review"></span> species.</li><li>The sequence in time of the fossil record equates with the increasing <input type="text" style="height: auto;" data-c="complexity"> <span class="review"></span> of living organisms from <input type="text" style="height: auto;" data-c="single-celled"> <span class="review"></span> to multicellular organisms.</li></ol></div><div class="q-explanation"><p><em>Fossils are good evidence of the evolution of life over a long time scale.</em></p></div><div class="actions"><span class="score" data-score="0"></span><button class="btn btn-default btn-sm btn-xs-block text-xs-center check"><i class="fa fa-check-square-o"></i> Check</button></div></div><div class="totals"><span class="score"></span><button class="btn btn-success btn-block text-center check-total"><i class="fa fa-check-square-o"></i> Check</button></div></div><hr> </div> </div> <div class="panel-footer"> <div> <p>text</p> </div> </div> </div> <div class="panel panel-fucsia"> <div class="panel-heading"><a class="expander pull-right" href="#"><span class="fa fa-plus"></span></a> <div> <p>Just for fun</p> </div> </div> <div class="panel-body"> <div> <p>Everyone needs a bit of fun while they revise. 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