Mock Exam 6
VCE Biology Units 3 & 4 | Human Evolution and the Evidence for Evolution
✎ 120 marks total • approximately 150 minutes. Complete ALL questions on paper before opening the Model Answers lesson. Reading time: 15 minutes (recommended). No notes.
SECTION A — MULTIPLE CHOICE (40 marks)
Question 1 (1 mark)
Which of the following best describes relative dating of fossils?
✎ Circle your answer
A) determining the age of a fossil in relation to other fossils/rock layers, based on stratigraphy (deeper layers are generally older)
B) calculating the exact numerical age of a fossil using radioactive isotope decay
C) comparing DNA sequences between species
D) measuring the exact chemical composition of a fossil only
Question 2 (1 mark)
Radiometric dating methods (e.g. carbon-14, potassium-argon) determine absolute age by:
✎ Circle your answer
A) comparing fossils in adjacent rock strata
B) measuring the ratio of a radioactive parent isotope to its stable daughter isotope, using the known half-life of the isotope
C) measuring the depth of sediment layers only
D) comparing morphological similarity between species
Question 3 (1 mark)
Carbon-14 dating is most useful for dating organic material up to approximately:
✎ Circle your answer
A) 4.5 billion years
B) 1 million years only
C) 50,000 to 60,000 years, due to carbon-14’s relatively short half-life (approximately 5,730 years)
D) it cannot date organic material at all
Question 4 (1 mark)
Potassium-argon dating, with a much longer half-life than carbon-14, is more appropriate for dating:
✎ Circle your answer
A) recently deceased organic tissue
B) fossils younger than 1000 years
C) fossils composed purely of soft tissue
D) much older volcanic rock layers surrounding hominin fossils, in the range of hundreds of thousands to millions of years
Question 5 (1 mark)
The law of superposition, used in relative dating, states that:
✎ Circle your answer
A) in an undisturbed sequence of sedimentary rock layers, deeper (lower) layers are older than layers above them
B) all rock layers form at the same time
C) fossils near the surface are always the oldest
D) radioactive decay rates change over time
Question 6 (1 mark)
A fossil is defined as:
✎ Circle your answer
A) any living organism
B) preserved evidence of past life, such as mineralised remains, imprints or casts
C) a rock formed only through volcanic activity
D) a DNA sample extracted from living tissue only
Question 7 (1 mark)
One limitation of the fossil record as evidence for evolution is that:
✎ Circle your answer
A) it provides no information about extinct species
B) it directly contradicts molecular evidence in all cases
C) fossilisation is a rare event, so the fossil record is incomplete, with gaps between related species
D) fossils cannot be dated at all
Question 8 (1 mark)
Homologous structures, such as the pentadactyl limb in humans, whales and bats, are evidence for evolution because they:
✎ Circle your answer
A) perform identical functions in every species that has them
B) arose completely independently with no shared ancestry
C) are always vestigial and non-functional
D) share a similar underlying anatomical structure inherited from a common ancestor, despite being adapted for different functions
Question 9 (1 mark)
Analogous structures, such as the wings of insects and the wings of birds, arise through:
✎ Circle your answer
A) convergent evolution, where unrelated species independently evolve similar features in response to similar environmental pressures, not shared ancestry
B) shared recent common ancestry
C) identical genetic pathways inherited from a single ancestor
D) homology
Question 10 (1 mark)
Vestigial structures, such as the human coccyx or appendix, provide evidence for evolution because they:
✎ Circle your answer
A) are fully functional structures essential for survival
B) are reduced, non-functional (or reduced-function) remnants of structures that had a function in ancestral species
C) only appear in fossils, never in living organisms
D) prove that humans evolved after all other hominins
Question 11 (1 mark)
Compared with other great apes, the human skull shows which distinguishing features associated with bipedalism and increased brain size?
✎ Circle your answer
A) a smaller cranial capacity and a posteriorly positioned foramen magnum
B) prominent brow ridges and a sagittal crest, identical to gorillas
C) a more anteriorly (centrally) positioned foramen magnum, larger cranial capacity, flatter face and reduced brow ridges
D) no differences at all from other great ape skulls
Question 12 (1 mark)
The position of the foramen magnum in hominin skulls is significant because it indicates:
✎ Circle your answer
A) diet type only
B) brain chemistry
C) age at death
D) posture and gait, a more forward/central position (underneath the skull) indicating habitual upright bipedal locomotion
Question 13 (1 mark)
A bowl-shaped, broader and shorter pelvis, as seen in Homo sapiens compared with other apes, is associated with:
✎ Circle your answer
A) efficient bipedal walking and support of upright body weight/internal organs
B) quadrupedal knuckle-walking
C) arboreal (tree-dwelling) locomotion only
D) egg-laying reproduction
Question 14 (1 mark)
Comparative anatomy across hominin species (e.g. Australopithecus vs Homo) is used as evidence for evolution by:
✎ Circle your answer
A) comparing DNA sequences exclusively, ignoring bone structure
B) examining shared and progressively modified skeletal features (skull, pelvis, limb proportions) to infer evolutionary relationships and trends over time
C) measuring the carbon-14 content of living tissue only
D) relying solely on the geographic location of fossil finds
Question 15 (1 mark)
Biogeography, as evidence for evolution, refers to the study of:
✎ Circle your answer
A) the chemical composition of fossils
B) the genetic code shared by all living things
C) the geographic distribution of species and how it relates to evolutionary history and historical continental positions
D) the dating of rocks using radioactive isotopes
Question 16 (1 mark)
Australia’s unique marsupial fauna, distinct from placental mammal-dominated continents, is best explained by:
✎ Circle your answer
A) marsupials being introduced to Australia recently by humans
B) marsupials evolving independently and identically on every continent
C) an absence of any common ancestor with other mammals
D) long-term geographic isolation following the break-up of Gondwana, allowing marsupials to diversify (adaptive radiation) largely free from placental mammal competition
Question 17 (1 mark)
Similar, but not identical, species found on separated continents that were once joined (e.g. ratite birds like the emu and ostrich) support evolution because they suggest:
✎ Circle your answer
A) descent from a common ancestral population that became geographically isolated after continental separation, subsequently diverging
B) simultaneous, independent creation of identical species
C) recent migration by flight across oceans
D) no evolutionary relationship at all
Question 18 (1 mark)
Which of the following is the best biogeographical evidence that Australia was once connected to South America and Antarctica (via Gondwana)?
✎ Circle your answer
A) identical DNA sequences in all placental mammals worldwide
B) related plant and animal lineages (e.g. southern beech Nothofagus, marsupials) found across Australia, South America and Antarctica, but nowhere else
C) the presence of humans on all three continents today
D) similar rock colour across the three continents
Question 19 (1 mark)
Island endemism (unique species found only on isolated islands, e.g. Galapagos finches) is explained by:
✎ Circle your answer
A) frequent gene flow with mainland populations preventing divergence
B) identical selective pressures to the mainland
C) geographic isolation allowing populations to diverge independently under local selective pressures, without significant gene flow from the mainland
D) the absence of natural selection on islands
Question 20 (1 mark)
Molecular evidence for evolution includes comparing which of the following between species?
✎ Circle your answer
A) only physical body size
B) only geographic location
C) only fossil age
D) DNA nucleotide sequences and amino acid sequences of homologous proteins
Question 21 (1 mark)
The degree of similarity in DNA or protein sequences between two species is generally used to infer:
✎ Circle your answer
A) how recently the two species shared a common ancestor, with greater similarity suggesting more recent common ancestry
B) the exact date the species will become extinct
C) which species is ‘more evolved’ or superior
D) nothing about evolutionary relationships
Question 22 (1 mark)
The molecular clock hypothesis assumes that:
✎ Circle your answer
A) mutations never occur in DNA
B) neutral mutations accumulate in DNA at a roughly constant, measurable rate over time, allowing divergence times between species to be estimated
C) all species share the exact same DNA sequence
D) protein sequences change but DNA sequences do not
Question 23 (1 mark)
Cytochrome c and haemoglobin are frequently used in molecular comparisons between species because they:
✎ Circle your answer
A) are found only in humans
B) have no known amino acid sequence
C) are highly conserved proteins present across many species, so differences in amino acid sequence can indicate evolutionary distance
D) mutate at a different rate in every individual organism
Question 24 (1 mark)
When comparing the amino acid sequence of a protein such as cytochrome c across species, humans and chimpanzees show almost no differences, while humans and yeast show many differences. This pattern indicates:
✎ Circle your answer
A) humans and yeast are more closely related than humans and chimpanzees
B) protein sequence differences are unrelated to evolutionary relationships
C) chimpanzees and yeast are equally related to humans
D) humans share a much more recent common ancestor with chimpanzees than with yeast
Question 25 (1 mark)
DNA hybridisation (DNA-DNA hybridisation) techniques estimate evolutionary relatedness by:
✎ Circle your answer
A) measuring how well single strands of DNA from two different species bind (anneal) together, with greater complementary base pairing indicating closer relatedness
B) sequencing the entire genome and physically comparing the number of chromosomes only
C) measuring the physical length of chromosomes
D) comparing only mitochondrial size
Question 26 (1 mark)
Mitochondrial DNA (mtDNA) is particularly useful in studying recent human evolutionary history because it:
✎ Circle your answer
A) undergoes recombination with paternal DNA every generation
B) is inherited maternally without recombination and mutates at a relatively consistent rate, allowing maternal lineages to be traced back in time
C) is identical in all humans, with no variation
D) is found only in the nucleus
Question 27 (1 mark)
The genus Australopithecus (e.g. Australopithecus afarensis, such as the fossil ‘Lucy’) is characterised by:
✎ Circle your answer
A) a fully modern human skeleton with a large brain
B) exclusively arboreal, non-bipedal locomotion
C) a relatively small brain (ape-like), combined with clear anatomical adaptations for bipedal walking
D) advanced stone tool technology and complex language
Question 28 (1 mark)
Homo habilis is significant in the hominin fossil record largely because it:
✎ Circle your answer
A) was the first hominin species to leave Africa
B) had a brain smaller than any Australopithecus species
C) had no association with any stone tools
D) is associated with the earliest recognised stone tools (Oldowan tools) and shows an increased cranial capacity compared with Australopithecus
Question 29 (1 mark)
Homo erectus is notable in human evolution for:
✎ Circle your answer
A) being the first hominin species widely accepted to have migrated out of Africa into Asia and Europe, with evidence of controlled use of fire
B) never leaving the African continent
C) having a smaller brain than Australopithecus
D) being genetically identical to modern Homo sapiens
Question 30 (1 mark)
Homo neanderthalensis (Neanderthals) were:
✎ Circle your answer
A) direct lineal ancestors of all modern humans with no distinct branching
B) a closely related but distinct hominin species/lineage that lived alongside early Homo sapiens in Europe and Asia before going extinct, with genetic and fossil evidence of limited interbreeding
C) identical in every physical respect to modern humans
D) found exclusively in Australia
Question 31 (1 mark)
Modern genetic evidence indicates that non-African modern human populations carry approximately what percentage of Neanderthal DNA?
✎ Circle your answer
A) 50%
B) 0%, with absolutely no interbreeding having occurred
C) approximately 1-2%, indicating limited interbreeding between Homo sapiens and Neanderthals
D) approximately 99%
Question 32 (1 mark)
The ‘Out of Africa’ (Recent African Origin) model of human evolution proposes that:
✎ Circle your answer
A) modern humans evolved independently and simultaneously on every continent from local Homo erectus populations
B) Homo sapiens first evolved in Europe before migrating to Africa
C) there is no evidence linking African fossils to modern human origins
D) anatomically modern Homo sapiens evolved in Africa and then migrated outward, progressively replacing other hominin populations across the globe
Question 33 (1 mark)
A cladogram (phylogenetic tree) showing hominin relationships is constructed primarily using:
✎ Circle your answer
A) shared derived characteristics (morphological and/or molecular) to group species according to relative recency of common ancestry
B) geographic location alone, with no reference to shared traits
C) alphabetical order of species names
D) body size alone
Question 34 (1 mark)
On a typical hominin phylogenetic tree, Homo sapiens and Homo neanderthalensis are shown as:
✎ Circle your answer
A) the exact same species with no distinguishing branch
B) sister lineages sharing a relatively recent common ancestor, having diverged from each other after both lineages split from earlier Homo populations
C) completely unrelated, with independent origins
D) ancestor and direct descendant, i.e. sapiens evolved directly from neanderthalensis
Question 35 (1 mark)
Charles Darwin’s theory of evolution by natural selection proposes that:
✎ Circle your answer
A) individuals can change their traits during their lifetime and pass the change on to offspring
B) all individuals in a population are genetically identical
C) heritable variation exists within populations, and individuals with traits better suited to their environment are more likely to survive and reproduce, passing those traits to offspring
D) evolution always proceeds towards a predetermined, perfect end goal
Question 36 (1 mark)
The evidence from fossils, comparative anatomy, biogeography and molecular biology is considered particularly powerful support for evolution because:
✎ Circle your answer
A) each line of evidence is studied in isolation and never compared with others
B) only one type of evidence (fossils) is actually reliable
C) the different types of evidence usually contradict one another
D) independent lines of evidence, obtained using different methods, converge on the same evolutionary relationships/pattern, increasing confidence in the theory
Question 37 (1 mark)
Evolution is described as a ‘unifying theory’ in biology because it:
✎ Circle your answer
A) provides an explanatory framework that connects and makes sense of observations across many biological disciplines, including genetics, anatomy, biogeography and palaeontology
B) applies only to fossils and has no relevance to living species
C) has been replaced by newer, unrelated theories
D) only explains the evolution of humans
Question 38 (1 mark)
Which of the following selective pressures is commonly proposed to have favoured the evolution of bipedalism in early hominins?
✎ Circle your answer
A) an abundance of dense, continuous forest cover with no need to travel
B) a changing environment with expanding savannah/grassland, favouring efficient long-distance walking, freeing the hands, and improved thermoregulation
C) an increase in average body size to a point where bipedalism became mechanically impossible
D) bipedalism providing no measurable survival or reproductive advantage
Question 39 (1 mark)
Increases in hominin brain size (encephalisation) over time are thought to have been driven by selective pressures including:
✎ Circle your answer
A) a decrease in social group complexity
B) reduced reliance on tool use
C) increasingly complex social behaviour, tool use, and dietary changes (e.g. increased access to energy-dense foods)
D) no identifiable selective advantage
Question 40 (1 mark)
Overall, the accumulated fossil, anatomical, biogeographical and molecular evidence for human evolution supports the conclusion that:
✎ Circle your answer
A) Homo sapiens appeared suddenly, with no anatomical or genetic connection to earlier hominins
B) each hominin fossil species is unrelated to modern humans
C) evolutionary relationships cannot be tested or supported by physical evidence
D) modern humans share a nested pattern of common ancestry with other hominins and, more distantly, with other primates, consistent with descent with modification over millions of years
SECTION B — EXTENDED RESPONSE (80 marks)
Question 1: Dating the Fossil Record
Question 41 (2 marks)
Question 1: Dating the Fossil Record (a)
A hominin fossil is discovered embedded between two layers of volcanic ash. State the dating technique most appropriate for dating the volcanic ash layers, and explain why the volcanic rock (rather than the fossil bone itself) is often dated using this technique.
✎ Write your answer on paper
Question 1: Dating the Fossil Record
Question 42 (3 marks)
Question 1: Dating the Fossil Record (b)
The ash layer below the fossil is dated to 2.0 million years old, and the ash layer above the fossil is dated to 1.8 million years old. Using these two ages, state what can be concluded about the age of the fossil and name the dating principle being applied.
✎ Write your answer on paper
Question 1: Dating the Fossil Record
Question 43 (4 marks)
Question 1: Dating the Fossil Record (c)
Explain the difference between relative dating and absolute (radiometric) dating, giving one example technique of each, and outline one limitation of each technique.
✎ Write your answer on paper
Question 2: Comparative Anatomy of Hominin Skulls
Question 44 (3 marks)
Question 2: Comparative Anatomy of Hominin Skulls (a)
Skull A has a small braincase (approximately 450cc), large brow ridges, a posteriorly positioned foramen magnum and a protruding (prognathic) jaw. Skull B has a large braincase (approximately 1350cc), small brow ridges, a centrally positioned foramen magnum and a flat face. Identify which skull is more likely to belong to Australopithecus and which is more likely to belong to Homo sapiens, justifying your answer with two features for each.
✎ Write your answer on paper
Question 2: Comparative Anatomy of Hominin Skulls
Question 45 (4 marks)
Question 2: Comparative Anatomy of Hominin Skulls (b)
Explain how the position of the foramen magnum and the shape of the pelvis together provide evidence for the evolution of bipedalism in the hominin lineage.
✎ Write your answer on paper
Question 2: Comparative Anatomy of Hominin Skulls
Question 46 (3 marks)
Question 2: Comparative Anatomy of Hominin Skulls (c)
Explain why comparative anatomy alone cannot definitively establish evolutionary relationships between species, and identify one additional type of evidence that should be used to support anatomical conclusions.
✎ Write your answer on paper
Question 3: Molecular Clock and Protein Comparison
Question 47 (3 marks)
Question 3: Molecular Clock and Protein Comparison (a)
The table below shows the number of amino acid differences (compared with the human sequence) in the protein cytochrome c across several species.
Chimpanzee: 0
Rhesus monkey: 1
Dog: 10
Chicken: 13
Yeast: 44
Describe the pattern shown by this data.
✎ Write your answer on paper
Question 3: Molecular Clock and Protein Comparison
Question 48 (3 marks)
Question 3: Molecular Clock and Protein Comparison (b)
Explain what this pattern suggests about the evolutionary relatedness of these species to humans, linking your answer to time since divergence from a common ancestor.
✎ Write your answer on paper
Question 3: Molecular Clock and Protein Comparison
Question 49 (4 marks)
Question 3: Molecular Clock and Protein Comparison (c)
For this question, assume cytochrome c accumulates amino acid differences between two lineages at a simplified constant rate of 1 amino acid difference per 7 million years since divergence. Using the data above, calculate the approximate time since humans and dogs last shared a common ancestor, showing your working. Then discuss ONE assumption or limitation of the molecular clock method.
✎ Write your answer on paper
Question 4: Biogeography and Continental Drift
Question 50 (3 marks)
Question 4: Biogeography and Continental Drift (a)
Explain, using the break-up of the supercontinent Gondwana, why Australia has such a high proportion of endemic marsupial species compared with other continents.
✎ Write your answer on paper
Question 4: Biogeography and Continental Drift
Question 51 (3 marks)
Question 4: Biogeography and Continental Drift (b)
Explain how the distribution of southern beech (Nothofagus) trees across Australia, New Zealand and South America supports the theory of continental drift and common ancestry.
✎ Write your answer on paper
Question 5: Interpreting a Hominin Cladogram
Question 52 (3 marks)
Question 5: Interpreting a Hominin Cladogram (a)
A simplified hominin cladogram shows a common ancestor splitting into two lineages: the Paranthropus lineage, and the Homo lineage. The Homo lineage then splits, giving rise to Homo habilis, then Homo erectus, which itself splits into Homo neanderthalensis and Homo sapiens. Using this cladogram, state which two species share the most recent common ancestor, and identify the closest related hominin lineage shown to Homo sapiens on this tree.
✎ Write your answer on paper
Question 5: Interpreting a Hominin Cladogram
Question 53 (3 marks)
Question 5: Interpreting a Hominin Cladogram (b)
Explain what a node (branch point) on a cladogram represents.
✎ Write your answer on paper
Question 5: Interpreting a Hominin Cladogram
Question 54 (4 marks)
Question 5: Interpreting a Hominin Cladogram (c)
Identify at least TWO different types of evidence that would be used to construct a hominin cladogram such as this one, and explain how ‘shared derived characteristics’ are used to group species together on the tree.
✎ Write your answer on paper
Question 6: Evolution as a Unifying Theory
Question 55 (5 marks)
Question 6: Evolution as a Unifying Theory
Explain why evolution is considered a ‘unifying theory’ in biology, referring to at least THREE different fields/lines of evidence that independently support it.
✎ Write your answer on paper
Question 7: Amino Acid Sequence Comparison Table
Question 56 (4 marks)
Question 7: Amino Acid Sequence Comparison Table (a)
A 10-amino-acid segment of a haemoglobin-like protein was compared across species, recording the number of amino acid differences from the human sequence: Chimpanzee = 1, Gorilla = 2, Mouse = 7. Using this data, rank the three species from most closely related to least closely related to humans, and justify your ranking.
✎ Write your answer on paper
Question 7: Amino Acid Sequence Comparison Table
Question 57 (4 marks)
Question 7: Amino Acid Sequence Comparison Table (b)
Explain why DNA sequence comparisons are generally considered a more precise/sensitive tool for measuring evolutionary relatedness than protein (amino acid) sequence comparisons alone.
✎ Write your answer on paper
Question 8: Selective Pressures in Human Evolution
Question 58 (3 marks)
Question 8: Selective Pressures in Human Evolution (a)
Outline TWO selective pressures proposed to have driven the evolution of bipedalism in early hominins.
✎ Write your answer on paper
Question 8: Selective Pressures in Human Evolution
Question 59 (3 marks)
Question 8: Selective Pressures in Human Evolution (b)
Explain, in terms of natural selection, how an increase in average hominin brain size could become established in a population over many generations.
✎ Write your answer on paper
Question 9: Neanderthal Genome and Interbreeding
Question 60 (3 marks)
Question 9: Neanderthal Genome and Interbreeding (a)
Describe the type of evidence used to determine that Homo sapiens and Homo neanderthalensis interbred, and state the approximate percentage of Neanderthal-derived DNA found in modern non-African human populations.
✎ Write your answer on paper
Question 9: Neanderthal Genome and Interbreeding
Question 61 (3 marks)
Question 9: Neanderthal Genome and Interbreeding (b)
Explain why populations of modern human ancestry that remained in Africa generally show little to no Neanderthal DNA, linking this to the Out of Africa migration model.
✎ Write your answer on paper
Question 10: Vestigial Structures
Question 62 (4 marks)
Question 10: Vestigial Structures
Using TWO named human vestigial structures, explain how they provide evidence of shared ancestry with other species.
✎ Write your answer on paper
Question 11: Out of Africa vs Multiregional Hypothesis
Question 63 (6 marks)
Question 11: Out of Africa vs Multiregional Hypothesis
Compare the ‘Out of Africa’ (Recent African Origin) model and the ‘Multiregional’ hypothesis for the origin of modern Homo sapiens, and outline ONE type of evidence that has been used to support the Out of Africa model over the multiregional hypothesis.
✎ Write your answer on paper
✓ Finished? Open the next lesson — Model Answers — to mark your work.
