t-» 'frs Cross-a-Clue VOCABULARY REVIEW- 3. Theory that evolutionary change occurs slowly and gradually Evolution: How Change Occurs J1.

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1 Name Class Date ( CHAPTR 14 volution: How Change Occurs VOCABULARY RVW- Cross-a-Clue Write the answers to the numbered clue$ on the l~nesprovided,these answers will give you the words to fill in on the crossword diagram below The crossword contains letter clues to help you place the word or words correctly " ffj N 'frs t-» L T ( 1 B J1 ~G N i c N 1 of the fittest is Darwin's explanation for diversity in nature 2 Form of evolution also known as adaptive radiation 3 Theory that evolutionary change occurs slowly and gradually,! '1a Prentice-Hall, nc 1

2 4 Form of evolution in which different organisms produce species that are similar in appearance and behavior 5 Author of On the Origin of Species 6 ndividuals of the same species that can interbreed and are located in a given area 7 Combination of an organism's habitat and its role in that habitat 8 Selection in which humans allow only the best organisms to produce offspring 9 Source of the random variation upon which natural selectiqn;6perates 10 Process in nature that is similar to artificial selection Process, also known as divergent evolution, in which " one species gives rise to many species 12 Term that describes the loss of an entire species 13 frequency describes the number of times a particular allele for a gene occurs in a gene pool 14 State of existence that involves very little or no change 15 xplains how new species evolve from existing species Prentice-Hall, nc

3 1 Name Class Date CHAPTR 14 t) volution: How Change Occurs Section 14-4 SKLL ACTVTY- Makinginferences' Finches in the Galapagos The Galapagos slands are located about 900 kilometers off the west coast of South America Volcanicactivity caused them to emerge from the sea about 3 million years ago n this activity you will learn about a group of finches that migrated to the Galapagos slands from the mainlandof SouthAmerica ' The finches, also known as Charles Darwin's finches, are among the best-known species on the Galapagos slands Darwin's observations of these birds helped him to formulate his ideas about evolution Since then, the finches have been studied in detail Their pattern of evolution is considered to be a classic example of adaptive radiation There are 14 species of finches on the Galapagos slands The table below contains a description of four habitats occupied by Darwin's finches Based on this information, answer the ~ questions that follow HABTATS (characteristic plants noted) t 1 The habitats described in the table contain different kinds of foods Natural selection produced different beak shapes in finches depending on the type of food in each habitat List and describe the characteristics of the new beaks that might have made it possible for the birds to adapt to the foods in each habitat Cacti: Treeless Zone/Fems, Dry/Cacti TropicallTree Moist/Trees Grasse 1 Nectar in cactus 1 Tree insects Tree leaves Seeds flowers 2 Flying 2 Tree seeds 2 nsects 2 Cactus spines insects 3 Fruit that can be used 3 Fruits" 4 Dense underbrush as prodding tools 4 Dense underbrush 3 Prickly cactus fruit 4 Parasitic ticks on bodies of iguanas 5 Open, rocky areas Tropical trees:, Moist Prentice-Hall, nc 3

4 Treeless zone: 2 For each area, what type of nesting sites and nesting materials might the birds have chosen? Cacti: 8 Tropical trees: Moist forest: Treeless zone: The figure below shows data on the lengths of the beaks of three species of Darwin's finches The percentage of individuals in each category of beak length is given ach of these species inhabits the ground ) " :c -'"0 OQ) Q)~ ClQ) lull) -0 fso eq) 0 5:~4 Species A Species B Species C,,~ Beak length (millim~ters) 3 a What is the shortest length of the beak observed in species A? b About what percentage of the birds of species A have this beak length? 4 What is the beak length of 45 percent of the birds of species A? 5 What is the beak length of most of the birds in species B? 6 What is the range of beak lengths for the birds of species C? 7 Based on the data, what can you predict about the size of the seeds eaten by each of these species of birds? Prentice-Hall, nc

5 Name Class Date CHAPTR 14 ) volution: How Change Occurs Section 14-5 SKLL ACTVTY- Applyingconcepts nvestigating Models of volution ) One of the major difficultieswith evaluating evolution is that the fossil record is incomplete n this activity you will investigate two models of evolution Charles Darwin proposed the theory of n(,lturalselection to explain evolution He said that species change gradually over time These small changes eventually resulted in new species Most scientists agree with Darwin's theory, but questions are still raised about parts of the theory One of the most important questions involves the rate of evolution f Darwin's theory of gradualism is correct, you would expect to see a range of slightly varying fossils leading from one species to the next However,the fossil record shows few intermediate forms Some scientists explain the gaps in the fossil record by pointing out that few organisms become fossils and it is likely that there are no fossils of many species Some scientists explain the gaps in the fossil record another way These scientists support the theory of punctuated equilibria, which explains that the gaps in the fossil record are gaps in evolution They believe Utat there are few intennediate forms as species evolve nstead, species remain unchanged for millions of years, then undergo rapid evolution The figure below illustrates two alternative ways of interpreting the same fossil data about body size ach straight line that is labeled with a letter stands for a species Angles indicate the points at which species diverged from an older species, forming new ones The greater the angle between two species, the greater the difference in body size Label the graphs to show which one illustrates punctuated equilibria and which one illustrates gradualism volution of New Species Graph 1 Graph 2 F GH CD F Q) F D B C A ---L- Bodysize Prentice-Hall, nc 7

6 n what ways are the two interpretations similar and in what ways are they different? 2 magine that a new fossil has been found from the timeiperiod between species A and species B as shown in Graph 1What prediction would you make about the size of the new fossil? xplainyour answer ~ Below are skulls from five different species Use them to answer the questions that follow 3 Use the theory of gradualism to explain the transitions between species A and species 4 How would you explain the same sequence using the theory of punctuated equilibrium? Prentice-Hall, nc