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Flashcards · Biology

Evolution and Natural Selection

112 cards from 7 lessons

  1. Who developed the theory of evolution by natural selection?

    Charles Darwin and Alfred Russel Wallace.

  2. What was the name of Darwin's ship?

    HMS Beagle.

  3. Which islands did Darwin study the finches on?

    The Galápagos Islands.

  4. When was On the Origin of Species published?

    1859.

  5. What happened in 1858?

    Wallace sent his paper to Darwin, and both were presented at the Linnean Society.

  6. Where did Wallace collect specimens?

    In the Amazon and South-East Asia.

  7. Why did Darwin delay publishing his theory?

    He wanted more evidence, and he knew the idea would upset many people.

  8. Give one reason why the theory was controversial.

    It conflicted with religious beliefs, or suggested a link between humans and apes.

  9. Why was it hard to accept the theory at first?

    There was no known mechanism for inheritance, and evolution is too slow to observe.

  10. What provided the mechanism Darwin lacked?

    Genetics, with the work of Mendel, and later DNA.

  11. What did Darwin learn from pigeon breeders?

    That choosing parents can produce new varieties, and nature could act in the same way.

  12. Why are the finches important?

    They showed how a single ancestor could give rise to species with different beaks.

  13. Which scientist had the idea independently of Darwin?

    Wallace.

  14. What is the common ancestor idea?

    All living things are descended from shared ancestors, and so are related.

  15. What phrase did Darwin use for the process?

    Natural selection.

  16. Common mistake about Darwin?

    Saying he invented the idea of evolution alone. Wallace had the same idea, and others before had suggested that species change.

  17. What is natural selection?

    The process by which better adapted individuals survive and reproduce, passing on their alleles.

  18. What are the five steps of natural selection?

    Variation, competition, survival of the best adapted, reproduction, and change in the population.

  19. Why do organisms compete?

    More offspring are born than the environment can support.

  20. What does survival of the fittest mean?

    The individuals best suited to the environment survive and breed.

  21. What is an adaptation?

    A feature that helps an organism to survive in its environment.

  22. Name three types of adaptation.

    Structural, behavioural and functional.

  23. Why are adaptations passed on?

    They are controlled by alleles.

  24. What happened to the peppered moths during the Industrial Revolution?

    The dark form became more common, because it was camouflaged on sooty trees.

  25. Why did the pale form become common again after 1956?

    The air was cleaner, the trees became paler and dark moths were seen more easily.

  26. What was Lamarck's idea?

    That characteristics acquired during life are inherited.

  27. Why is Lamarck's idea wrong?

    Acquired characteristics do not change the genes in the gametes.

  28. What is speciation?

    The formation of a new species.

  29. How can a new species form?

    A population is isolated, different selection acts on each group, and they can no longer interbreed.

  30. What does the proportion of an allele do over many generations if it is advantageous?

    It increases.

  31. Does natural selection happen in an individual during its lifetime?

    No. It acts on a population over generations.

  32. Common mistake about natural selection?

    Saying that organisms change because they need to. Variation is already there, and selection acts on it.

  33. What are antibiotics?

    Drugs that kill bacteria or stop them from growing.

  34. Do antibiotics work on viruses?

    No.

  35. What is antibiotic resistance?

    The ability of bacteria to survive an antibiotic.

  36. How does a bacterium become resistant?

    By a mutation, which gives variation in the population.

  37. What is the selection pressure in antibiotic resistance?

    The antibiotic.

  38. What happens to non-resistant bacteria when an antibiotic is used?

    They are killed.

  39. What do the resistant bacteria do?

    Survive and reproduce, and pass on the resistance allele.

  40. Why can bacteria evolve so fast?

    They reproduce very quickly, so there are many generations in a short time.

  41. What does MRSA stand for?

    Methicillin-resistant Staphylococcus aureus.

  42. Why is antibiotic resistance a problem?

    Infections become hard to treat, and surgery and other treatments become risky.

  43. Why should patients finish a course of antibiotics?

    To kill all of the bacteria, and not leave the resistant ones to survive.

  44. Why should antibiotics not be used for colds?

    Colds are caused by viruses, which antibiotics do not kill, and using them increases resistance.

  45. How does handwashing help?

    It reduces the spread of resistant bacteria.

  46. Does the antibiotic cause the mutation?

    No. The mutation happens by chance, and the antibiotic selects the bacteria that have it.

  47. Why is antibiotic resistance an example of evolution?

    The proportion of resistant bacteria increases by natural selection.

  48. Common mistake about resistance?

    Saying that the person becomes resistant. It is the bacteria that become resistant.

  49. How old is Ardi?

    About 4.4 million years.

  50. How old is Lucy?

    About 3.2 million years.

  51. How old are the Leakey Homo erectus fossils?

    About 1.6 million years.

  52. Where were Ardi and Lucy found?

    In Ethiopia.

  53. Which fossil was found by Donald Johanson?

    Lucy.

  54. What was Ardi's brain volume?

    About 300 to 350 cm³.

  55. What was Lucy's brain volume?

    About 400 cm³.

  56. What was the Homo erectus boy's brain volume?

    About 880 cm³.

  57. What did Lucy's pelvis show?

    She walked upright on two legs.

  58. Why did Ardi have a grasping toe?

    To climb trees.

  59. What evolved first, walking upright or a big brain?

    Walking upright.

  60. Give one limitation of the fossil record.

    It is incomplete, because few organisms are fossilised.

  61. Why do scientists disagree about fossils?

    Often only a few bones are found, so they are hard to classify.

  62. Which animal is our closest living relative?

    The chimpanzee.

  63. Where in the world were most early hominid fossils found?

    East Africa.

  64. Common mistake about human evolution?

    Saying humans evolved from chimpanzees. We share a common ancestor.

  65. Why do stone tools last so long?

    Stone does not rot, so it survives for millions of years.

  66. What are the oldest well-known stone tools called?

    Oldowan tools.

  67. What species made the Oldowan tools?

    Early Homo, such as Homo habilis.

  68. What shape were hand axes?

    Symmetrical and teardrop shaped, worked on both sides.

  69. Which species made hand axes?

    Homo erectus.

  70. Which later tools were made by modern humans?

    Thin blades, and tools of bone and antler.

  71. What do more complex tools suggest about their makers?

    They had more skill, planning and a larger brain.

  72. How are stone tools dated?

    From the rock layers around them, or by dating the volcanic ash or other material found with them.

  73. Are deeper layers of rock older or younger?

    Older.

  74. A tool lies between two ash layers dated at 1 and 1.8 million years. What is its age?

    Between 1 and 1.8 million years old.

  75. What can be dated by carbon-14?

    Organic remains up to about 50 000 years old.

  76. Give a limitation of stone tools as evidence.

    Wooden tools rot away, or the maker is not known.

  77. Why might a tool be in the wrong layer?

    Erosion or animals may have disturbed the layers.

  78. What did the Lomekwi tools show?

    That tool making began about 3.3 million years ago, earlier than expected.

  79. Why do scientists use more than one dating method?

    To cross-check, which makes the result more reliable.

  80. Common mistake about dating a tool?

    Saying that the stone itself is dated. The surrounding layers or material are dated.

  81. What is a pentadactyl limb?

    A limb with five digits and a common pattern of bones.

  82. Name the bone in the upper limb.

    The humerus.

  83. Name the two bones in the lower limb.

    The radius and the ulna.

  84. What are the bones of the wrist called?

    Carpals.

  85. What are the bones of the fingers called?

    Phalanges (digits).

  86. Name four animals with a pentadactyl limb.

    Human, bat, whale and horse.

  87. What is the function of a bat's wing?

    Flying.

  88. What is the function of a whale's flipper?

    Swimming.

  89. What does the same pattern of bones suggest?

    That the animals share a common ancestor.

  90. What has changed the limbs for different functions?

    Natural selection.

  91. What is a homologous structure?

    A structure with the same arrangement of parts, but possibly a different function.

  92. What is an analogous structure?

    A structure with the same function but a different origin, such as the wings of a bird and an insect.

  93. Are insect and bird wings homologous?

    No. They are analogous.

  94. Why is the horse leg adapted for running?

    It is long with few digits, ending in a hoof.

  95. What is divergent evolution?

    Related species evolving different features from a common ancestor.

  96. Common mistake about the pentadactyl limb?

    Saying the animals evolved from each other. They share a common ancestor.

  97. What are the five kingdoms?

    Animals, plants, fungi, protists and prokaryotes.

  98. Who proposed the three domain system?

    Carl Woese.

  99. When was the three domain system proposed?

    1977.

  100. What are the three domains?

    Bacteria, Archaea and Eukaryota.

  101. What kind of evidence led to the three domains?

    Genetic analysis, such as comparing ribosomal RNA genes.

  102. Which domain includes plants and animals?

    Eukaryota.

  103. What is the difference between archaea and bacteria?

    Archaea have different genes, cell membranes and ribosomes, and often live in extreme environments.

  104. Do archaea have a nucleus?

    No, they are prokaryotes.

  105. Which kingdom do fungi belong to?

    Fungi, within the domain Eukaryota.

  106. What is a binomial name?

    A two-part Latin name, with the genus first and the species second.

  107. What is the binomial name for humans?

    Homo sapiens.

  108. Why was the five kingdoms system changed?

    Genetic evidence showed that the prokaryotes were two very different groups.

  109. Why are genes better for classification than appearance?

    Appearance can be misleading, but genes show evolutionary relationships.

  110. Name an extreme habitat in which archaea live.

    Hot springs, salt lakes or deep-sea vents.

  111. Why do scientists revise classification?

    New evidence, such as DNA sequences, shows new relationships.

  112. Common mistake about classification?

    Thinking it is fixed. It changes with new evidence.