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QUESTION 5 The figure shows the diversity of marine animals since the late Precambrian time. The data is from marine animal families that have been reliably preserved in the fossil record. 19OOT families 900 living 800 today 700 600 500 400 300 200 100 Number of marine families o Triassic - Jurassic Cretaceous Paleogene Neogene Ordovician Silurian Devonian Carboniferous Precambrian Cambrian p— S ) S 600 200 W S O N S S Millions of years ago Which of the following time periods saw the greatest evolutionary radiation of the marine families? (A) Ordovician (B) Cretaceous (C) Devonian (D) Permian
QUESTION 18 The diagram shows the abundance (n) of phenotypic and genotypic variation for the colour trait of a species of butterfly. AA Aa aa n =400 n =500 n= 1000 If these butterflies were placed in an environment with light-coloured trees which option from the table would be the most likely effect on the allelic frequencies? Frequency of allele/genotype A | 2 | AA | I = -- -- --
QUESTION 20 Which of the following are features of both microevolution and macroevolution? (A) mutations only (B) mutations and gene flow only (C) gene flow and genetic drift only (D) mutations gene flow and genetic drift
QUESTION 26 (1 mark) Define microevolution.
QUESTION 27 (4 marks) In a freshwater lake in Africa a species of crab and its snail prey species both exhibit specialisations that are unusual for freshwater species. The crabs possess strong claws with characteristics of marine crabs that crush and peel shells and the snail prey have thick strong shells that resist crushing. a) Identify which pattern of evolution this example represents. [1 mark] b) Describe how the two species may have evolved these characteristics. [3 marks]
QUESTION 9 (3 marks) Fossil evidence seems to show that the morphology of the Queensland lung fish has remained relatively unchanged for the past 100 million years. Describe the features of the theory of natural selection to explain how this may have occurred.
QUESTION 10 (3 marks) Researchers measured the adult beak lengths of an entire population of a species of bird and plotted their results on the graph. After many generations the lengths of the adult beaks were again measured. By comparing this new data to the original data the researchers concluded that the average length of beaks had increased as a result of directional selection. nitial distribution / of beak lengths Frequency 0 5 10 15 20 Beak length (mm) a) Describe directional selection. [2 marks]
QUESTION 11 (6 marks) The image shows changes in the frequency of a particular gene in a single species of bird leading to a speciation event. These changes have occurred over a period of successive time points (i.e. I IT and III) each separated by approximately 1000 generations. » The letters A B C and D represent separate niches inhabited by the birds. * The arrows depict gene flow between the niches. » The allelic frequency for the gene is shown as f in each niche. 1 111 Draw a conclusion about the type of speciation that has occurred in this population. Explain your reasoning by referring to the information provided in each of the time points.
QUESTION 7 In a long-term study of grasshopper colour in a grassland ecosystem it was found that the most abundant phenotype changed from dark green to straw yellow. dark green straw yellow L7 Population Phenotypic trait (colour) This change in the phenotype is an example of (A) diversifying selection. (B) directional selection. (C) stabilising selection. (D) disruptive selection.
QUESTION 10 The forelimbs of humans dogs birds and whales have a very similar pattern of bones. Human Bird Whale Not to scale The similarity of these structures is best explained by which pattern of evolution? (A) convergent evolution (B) divergent evolution (C) parallel evolution (D) coevolution
QUESTION 16 A small group of dingoes migrated to a new area and established a population. After several generations the new population showed a different genetic composition from the original population. This is an example of (A) microevolution and gene flow. (B) macroevolution and gene flow. (C) microevolution and genetic drift. (D) macroevolution and genetic drift.
QUESTION 18 Which scenario would create a selection pressure on a given population? (A) change in fur colour (B) change in weather patterns (C) greater resistance to disease (D) 1mproved ability to locate food sources
QUESTION 27 (3 marks) The table shows the percentage sequence similarity for three different parts of a gene found in four different eukaryotic species. The data was obtained by comparing DNA from one member of each species to Species A. From this data a proposed phylogenetic tree was produced. 100% 100% 100% e e | e | w o [ [ | D A ™ a Determine whether the phylogenetic tree has been drawn correctly based on the DNA comparison. Explain your reasoning.
QUESTION 7 (3 marks) Koalas were once widespread in Australia. Due to a variety of factors their population decreased and fragmented into small pockets forcing them to inbreed. They have recently been hit by devastating epidemic diseases. Explain why koalas face an increased extinction risk from disease.
QUESTION 8 (3 marks) Australia has many bird species that have evolved to be largely dependent on mangroves. These species are patchy in their distribution because of: « the island-like distribution of their habitat * exclusion by possible competitors » geographical barriers. Identify and describe the mode of speciation that may have caused diversity in mangrove bird species.
QUESTION 9 (3 marks) A computer simulation was used to observe genotypic changes in the gene pool of 20 randomly selected rabbits. The simulation was set with these parameters: each rabbit’s coat colour was either black or white » black alleles were dominant; white alleles were recessive « the number of rabbits was constant in each generation and breeding was random throughout the population « an environmental factor was chosen in the simulation to provide selection pressure. The table shows the results of the simulation at the start and after 20 generations. Initial population genotypes Population genotypes after 20 generations BB BB BB BB BB BB BB BB Bb Bb Bb Bb Bb Bb Bb Bb Bb Bb Bb Bb Bb Bb Bb Bb Bb Bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb Contrast the initial allele frequency with the allele frequency after 20 generations to draw a conclusion about the effect of the selection pressure on the rabbit population.
QUESTION 4 The graph shows the effect of a selection pressure on a hypothetical population. Phenotype Key [ ] Before the selection pressure B 20 generations later Number of individuals Which mode of phenotypic selection corresponds with the data? (A) negative (B) disruptive (C) stabilising (D) directional
QUESTION 10 Wings in birds bats and pterosaurs are phenotypically similar though they belong to different families and do not have a common ancestor with the trait. While the general morphology is similar the structure and organisation of each wing is different. This is an example of (A) coevolution. (B) parallel evolution. (C) divergent evolution. (D) convergent evolution.
QUESTION 12 Speciation occurs when (A) the gene pool of an existing species becomes too small to support a viable population. (B) selection pressures cause significant changes to the allele frequencies of a population. (C) genetic drift is no longer occurring within populations. (D) gene flow is no longer occurring between populations.
QUESTION 23 (3 marks) Compare microevolution and macroevolution.
QUESTION 28 (3 marks) In 1950 the myxoma virus was released into Australian pest rabbit populations to reduce their numbers. The resulting disease myxomatosis initially wiped out 95% of the rabbit population; however it quickly became less effective as a population control measure. This graph shows the frequency of myxomatosis resistance in Australia’s rabbit population from 1949 to 1956. 100 90 S 5 80 o < = 70 5 2 60 & £ 50 o % = 40 (- o > 30 a 3 g 20 [ 10 'v . — | 1949 1950 1951 1952 1953 1954 1955 1956 Year Use evidence from the graph and the principles of natural selection to explain how myxomatosis became ineffective as a population control measure.
QUESTION 8 (3 marks) Over time the South African cheetah population has suffered drastic reduction due to periodic droughts disease and hunting. Currently only small isolated populations of cheetahs exist in the wild. Explain in terms of genetic diversity why cheetah populations are now on the verge of extinction.
QUESTION 11 (8 marks) Allele frequencies were monitored in two large populations of field mice from neighbouring forests over a 10-year period. Results are shown. Forest X [ e s a) Calculate the allele frequencies for forest Y in 2018. Show your working. [2 marks] b) Identify temporal trends in allele frequency for forests X and Y and infer reasons for the observed differences. [6 marks]
QUESTION 6 Which of the following does not cause macroevolution? (A) time (B) mutation (C) extinction (D) speciation
QUESTION 18 Evolution during successive generations is a change in the (A) (B) ©) (D) small-scale variation of species’ allele frequencies. genetic transmission of characteristics. genetic composition of a population. divergence of taxonomic groups.
QUESTION 20 The graphs below show the trait distribution of a hypothetical population before and after selection. The dotted line indicates the mean of each population. Before selection After selection » 40 ; » 40 3] © . 2 £ s 5 o0 s o0 © ° 2 c c . w 20 w 20 : o o 2 10 2 10 £ g - - < 0 : Z 0 : 0 2 4 6: 8 10 12 14 0 2 4 6 : 8 10 12 14 Phenotype mean Phenotype mean The type of phenotypic selection represented in the graphs is (A) divergent. (B) disruptive. (C) stabilising. (D) directional.
QUESTION 22 Island populations are often isolated and can face an increased risk of extinction because of (A) 1improved reproductive fitness. (B) reduced genetic diversity. (C) decreased genetic drift. (D) unrestricted gene flow.
QUESTION 24 The figure below shows an evolutionary timeline indicating episodes of evolutionary radiation. Mammals Therapsida Birds Synapsida Sauropsida Archosauria Reptiles Permian Triassic Jurassic Cretaceous Palaeogene Palaeozoic Mesozoic Cenozoic 300 250 200 150 100 50 0 Million years ago (Ma) In which period did the radiation of mammals occur? (A) Triassic (B) Jurassic (C) Cretaceous (D) Palaeogene
QUESTION 26 (4 marks) Explain microevolutionary change through mutation.
QUESTION 28 (5 marks) The figure below shows a model of ecological niche occupation by species A—E. : T :_¢§ Species D - ‘© 2 | ® % © . m = 2 Z 2 3 Cool Warm Niche axis 2 — Temperature a) Identify which two species are occupying the same ecological niche. [1 mark] b) Species A and B have a common ancestor. Which diversification pattern would have occurred between species A and species B for them to occupy these niches? [1 mark] The table below shows the frequencies of genotypes and phenotypes for a particular trait in a generation of species E. Genotype (% frequency) Phenotype (% frequency) TT (0) Tt (100) tt (0) Phenotype 2 (0) c) Predict the next generation’s genotype and phenotype frequency. Which type of inheritance pattern is represented for Phenotype 17 Phenotype 1 (100) [3 marks]
QUESTION 4 Populations with reduced genetic diversity face an increased risk of extinction because they (A) have fewer chromosomes. (B) have difficulty finding mates for reproduction. (C) are less likely to adapt to changing environments. (D) contain a larger proportion of heterozygous individuals.
QUESTION 7 The distributions of phenotypes before and after a selection pressure acted on a population are shown. Which graph shows disruptive selection? === Before selection pressure 25 generations later (A) (B) Number of individuals Number of individuals (C) (D) Number of individuals Number of individuals Phenotype
QUESTION 10 The graph shows extinction rates over time. a ee NO) PPD PS 107 Extinction rate (families per million years a a re 500 450 400 350 300 250 200 ©1506 6100 8§©650 0 Millions of years ago (Mya) How many times in the past 500 million years has the extinction rate exceeded 14 families per million years? (A) 3 (B) 4 (C) 5 (D) 6
QUESTION 15 Allele frequencies are most likely to stay constant in (A) large populations with low levels of migration. (B) small populations with low levels of migration. (C) large populations with high levels of migration. (D) small populations with high levels of migration.
QUESTION 24 (5 marks) The frequency of a new allele was monitored in a population of insects over an 18-year period. Frequency 0.0 2004 2006 2008 2010 2012 2014 2016 2018 2020 2022 Year a) Infer if the new allele is advantageous or detrimental in this environment. Justify your response using evidence from the graph. [2 marks] b) Explain how mutations can contribute to microevolutionary change in populations [3 marks] that reproduce sexually.
QUESTION 4 (5 marks) The hummingbird hawkmoth (phylum: Arthropoda) is named for its similarity to hummingbirds (phylum: Chordata). The two species have independently developed similar feeding structures which they use to draw nectar from tube-shaped flowers. Both species help plants reproduce by distributing their pollen. a) b) c) Hummingbird hawkmoth Hummingbird Identify the diversification pattern demonstrated by the hummingbird and the hummingbird hawkmoth. [1 mark] Use the principles of natural selection to explain the similarities between the two species. [2 marks] Explain how coevolution of the hummingbird hawkmoth and tube-shaped flowers may have occurred. [2 marks]
QUESTION 8 (3 marks) Explain how temporal isolation can lead to speciation.
QUESTION 5 (3 marks) Nucleic acid sequences were used to investigate evolutionary relationships between four species. Species Nucleic acid sequence GACCGCATTTACGTA GACGTCATATCCGTA a) b) GACCGCATTTCCGTA GACGGCATATCCGTA Explain how data from conserved molecular sequences can be used to estimate time since divergence. Use the data to infer species I-IV in the cladogram. Species Species Species Species I: B. bartonus II: [2 marks] [1 mark] Il:
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