Deck 3: What the Rocks Say: How Geology and Paleontology Reveal the History of Life

Question 1

What is coal?

A) the remnants of fires created by ancient humans
B) highly compacted marine sediments
C) the remains of ancient buried plants
D) dinosaur bones that have been exposed to pressure

Answer 1

C

Question 2

Which of the following allowed scientists to determine whether early hominins were browsers (eating shrubs primarily) or grazers (eating grasses primarily)?

A) Shrubs and grasses differ in the type of photosynthesis they perform.
B) Shrubs and grasses have different carbon isotopic signatures.
C) Fossil remains of plants surrounding hominins indicate what they most likely ate.
D) a and b
E) a, b, and c

Answer 2

D

Question 3

Which of the following statements about countershading is true?

A) Countershading is widespread among living mammals, but there are no known instances of it in dinosaurs.
B) Countershading helps obscure the shadow cast by an animal, making it harder for predators to see it.
C) Only large predators use countershading to blend into their surroundings so that their prey cannot see them.
D) Countershading cannot be inferred from the fossil record because skin and scale tissue is never preserved.

Answer 3

B

Question 4

Which of the following incorrectly matches the event with its age in the fossil record?

A) evidence of nonsedentary animals 585 million years ago
B) evidence of large animals - 570 million years ago
C) extinction of the Ediacaran fauna - 570 million years ago
D) earliest evidence of chordates - 515 million years ago

Question 5

The oldest fossils may be

A) fossilized bacterial mats called stromatolites.
B) microscopic bits of carbon know as zircons.
C) marine animals from the Burgess Shale.
D) petrified pollen grains from ancient plants.

Question 6

Which of the following might be a useful organism to study to the emergence of multicellularity?

A) Streptococcus mutans, a biofilm forming bacteria that causes dental plaque
B) Dictyostelium discoideum, a unicellular slime mold that can form slug-like masses
C) Paramecium caudatum, an animal-like protist that is a complex unicellular organism
D) a and b
E) a, b, and c

Question 7

The rise of the cyanobacteria lineage 2.6 billion years ago corresponds to

A) the earliest evidence we have of life on Earth.
B) the emergence of chloroplasts.
C) a rise in atmospheric oxygen.
D) an increase in global temperature.

Question 8

What did carbon-14 dating reveal about Neanderthals and modern humans?

A) Neanderthals and modern humans coexisted in Europe 40,000 years ago.
B) Modern humans and Neanderthals only coexisted for a few thousand years before the Neanderthals disappeared.
C) Neanderthals and modern humans interbred for a few thousand years.
D) a and b
E) a, b, and c

Question 9

Darwin believed that Earth was

A) a few thousand years old.
B) 300 million years old.
C) a few billion years old.
D) 20 million years old.

Question 10

How do medical technologies help elucidate the fossil record?

A) CT scans reveal the ancient diseases of extinct organisms.
B) MRI scans reveal how fossilized tissue may have functioned.
C) CT scans reveal the detailed structure of fossilized bones.
D) Medical technologies can not be used to study the fossil record.

Question 11

Why was Lord Kelvin's calculation of Earth's age inaccurate?

A) He assumed that Earth was a rigid sphere.
B) He assumed that heat is lost at a constant rate.
C) He only measured heat on surface rocks.
D) a and b
E) a, b, and c

Question 12

A fossilized Homo sapiens specimen is found to be 195,000 years old. How was this age most likely determined?

A) by calculating the ratio of C-14 to C-12 in the fossilized remains
B) by calculating the ratio of rubidium to strontium in the fossilized remains
C) by calculating the ratio of potassium to argon in the rock layers above and below the fossil
D) by calculating the ratio of C-14 to C-12 in the rock layers above and below the fossil

Question 13

The human body is composed of approximately

A) 40 trillion cells.
B) 30 trillion cells.
C) 1 trillion cells.
D) 300 billion cells.

Question 14

The earliest evidence of multicellularity dates back to

A) 3.5 billion years ago.
B) 2.6 billion years ago.
C) 2.1 billion years ago.
D) 1.6 billion years ago.

Question 15

The oldest currently known fossil of a land animal is

A) a tetrapod.
B) a bird.
C) a millipede.
D) bacteria.

Question 16

Which of the following is true about isotopes with high decay rate probabilities?

A) They decay rapidly.
B) They are very radioactive.
C) They cannot be used in radiometric dating.
D) a and b
E) a, b, and c

Question 17

What does the fossil record reveal about the locomotory behavior of Tyrannosaurus rex?

A) It was a fast runner, like an ostrich.
B) It had a sprawling gait, like a crocodile.
C) It was incapable of running fast.
D) Its small arms were leveraged to generate a running force.

Question 18

Which of the following is true regarding hominin evolution?

A) Evidence of Homo sapiens first appears 300,000 years ago in the fossil of a jaw.
B) One of the earliest hominins, Sahelanthropus, dates back to seven million years ago.
C) The earliest evidence of hominins with our human-like stature date back to two million years ago.
D) a and c
E) a, b, and c

Question 19

Which of the following is not a teleost?

A) tuna
B) salmon
C) shark
D) goldfish

Question 20

Which of the following incorrectly matches the group with its emergence in the fossil record?

A) extant mammal groups - 160 million years ago
B) dinosaurs - 350 million years ago
C) flowering plants - 136 million years ago
D) insects - 400 million years ago

Question 21

Which of the following could be considered a biomarker?

A) okanane, a derivation of the pigment in purple sulfur bacteria
B) amino acids found in interstellar clouds
C) carbon-13:carbon-12 ratio
D) a and c
E) a, b, and c

Question 22

What does the signature of carbon-13:carbon-12 in the fossil record indicate about the history of hominin behavior?

A) Early hominins consumed only grasses.
B) Early hominins consumed only shrub-like plants.
C) There was a gradual shift in hominin diet from shrub-like plants to grasses.
D) There was a gradual shift in hominin diet from grasses to shrub-like plants.

Question 23

Modern-day mammals are descended most recently from what group?

A) synapsids
B) reptiles
C) fish
D) amphibians

Question 24

How do paleontologists date fossils?

A) directly using carbon dating
B) indirectly by studying the age of rock layers
C) directly using radiometric dating
D) a and b
E) a, b, and c

Question 25

Hominins include

A) Homo sapiens only.
B) species within the genus Homo only.
C) Homo sapiens and other extinct species more closely related to humans than to chimpanzees.
D) humans, both extinct and extant, and the great apes.

Question 26

Nearly all currently existing animal lineages evolved during which period?

A) Ediacaran
B) Precambrian
C) Cambrian
D) Cryogenian

Question 27

Animals differ as a kingdom because they

A) use photosynthetic pigments to obtain energy.
B) release enzymes to break down the matter of organisms.
C) have bodies that can consume other organisms.
D) have toxins for protection.

Question 28

How does the process of fossilization occur?

A) Bones become rocks when exposed to high temperatures.
B) Minerals seep into the spaces of bones, turning them into rocks.
C) Bones are buried deep in the ground by sediment and later exposed.
D) The Sun dries out bones until they are hardened and preserved.

Question 29

Fossils of red algae in India date back to

A) 2.6 billion years ago.
B) 2.1 billion years ago.
C) 1.6 billion years ago.
D) 600 million years ago.

Question 30

Life may have existed as long ago as

A) 4.8 billion years ago.
B) 4.56 billion years ago.
C) 4.4 billion years ago.
D) 4.1 billion years ago.

Question 31

Tetrapods include

A) organisms descended from ancestors with four limbs.
B) birds.
C) whales.
D) all of the above

Question 32

Which of the following statements is true about Earth's atmosphere?

A) It formed from gases released from rocks in early Earth.
B) Its composition has changed over the history of Earth.
C) It originally had much more oxygen than today, making the early atmosphere toxic to most of the life that exists today.
D) a and b
E) a, b, and c

Question 33

Which of the following is not a reason that an organism would be unlikely to be discovered in fossilized form?

A) Most organisms are eaten or otherwise degraded to the point where there is nothing left to fossilize.
B) Soft-bodied organisms are unlikely to fossilize.
C) A fossil must rise to the surface of Earth.
D) A fossil must be discovered.
E) all of the above

Question 34

Oceans probably existed by

A) 4.56 billion years ago.
B) 4.4 billion years ago.
C) 4 billion years ago.
D) 3.8 billion years ago.

Question 35

The Burgess Shale is an example of a(n) ________ with a wealth of data from the ______ period.

A) Lagerstätte; Cambrian
B) stromatolite; Cryogenian
C) Lagerstätte; Ediacaran
D) Ediacaran; Lagerstätte

Question 36

Which of the following incorrectly matches the event with its age in the fossil record?

A) oldest vertebrate trackways - 390 million years ago
B) oldest vertebrate fossils - 370 million years ago
C) oldest land animal - 350 million years ago
D) oldest fungi fossils - 440 million years ago

Question 37

Lord Kelvin argued that based on the temperature of rocks, Earth could not be as old as some geologists thought. What turned out to be wrong with his reasoning?

A) He claimed that the temperature of surface rocks should be used in calculations, but these calculations were shown to be unreliable.
B) He did not realize that the planet's interior was constantly changing.
C) The upper layers of Earth are cooler than Kelvin realized.
D) all of the above

Question 38

Molecular evidence of living organisms found in the fossil record is called

A) endosymbionts.
B) biomarkers.
C) isotopes.
D) microfossils.

Question 39

The diversification of grasses has mostly occurred in the last 20 million years. Some scientists have argued that this can be explained by

A) the decline of large herbivores.
B) the extinction of dinosaurs.
C) a decline in the concentration of carbon dioxide in the atmosphere.
D) the emergence of insects.

Question 40

Animals are most closely related to which major lineage of organisms?

A) Bacteria
B) Plants
C) Fungi
D) Algae

Question 41

Which of the following is not true about unstable isotopes?

A) Unstable isotopes have a fixed probability of decaying.
B) Earth's natural supply of unstable isotopes is steadily increasing.
C) Unstable isotopes and stable isotopes have a different ratio of neutrons to protons.
D) Geologists use unstable isotopes to estimate precise ages for geological formations.

Question 42

Eukaryotes differ from archaea and bacteria because

A) they contain a nucleus.
B) the cell membrane contains peptidoglycan.
C) they contain mitochondria.
D) a and c
E) a, b, and c

Question 43

Why is it hard to find rocks from Earth's early history?

A) because of heavy bombardments that melted most of Earth's crust up until 3.8 billion years ago
B) because of plate tectonics that destroyed rocks
C) because rocks are ephemeral structures
D) a and b
E) a, b, and c

Question 44

The earliest generally accepted fossils of living organisms are

A) yeasts.
B) stromatolites.
C) zircons.
D) carbon isotopes.

Question 45

The Ediacaran fauna includes

A) organisms that lived on land.
B) tetrapods.
C) organisms that are not clearly related to any currently existing lineages.
D) chordates.

Question 46

Earth formed

A) 4.6 billion years ago, and the earliest traces of life appear immediately thereafter.
B) 4 billion years ago, and the earliest traces of life appear immediately thereafter.
C) 4.6 billion years ago, and the earliest traces of life appear approximately 500-600 million years later.
D) 4 billion years ago, and the earliest traces of life appear approximately 500-600 million years later.

Question 47

What was the crest of a hadrosaur likely used for?

A) It housed a larger brain to allow it to better navigate its environment.
B) to process smells and increase predatory abilities
C) to generate species specific sounds
D) Scientists currently do not know what the crest of the hadrosaur was used for.

Question 48

The earliest fossils of our own species date to

A) approximately 500,000 years ago.
B) approximately, 2 million years ago.
C) approximately 6 million years ago.
D) approximately 300,000 years ago.

Question 49

Stromatolites are structures of mineralized layers created by

A) bacteria.
B) archaea.
C) sponges.
D) corals.

Question 50

The two lineages of prokaryotes, Archaea and Bacteria, probably diverged

A) 4.1 billion years ago.
B) 3.5 billion years ago.
C) 2.6 billion years ago
D) 1.6 billion years ago.

Question 51

Which of the following is true about Earth?

A) Earth is a dynamic planet.
B) Earth is made up of solid plates that float on a molten layer of rock.
C) Gradual geological processes have shaped the Earth.
D) all of the above

Question 52

Eukarya emerge in the fossil record ____ billion years ago and were _____ the size of prokaryotes.

A) 2.6; 10 times
B) 1.6; 100 times
C) 3.5; 10 times
D) 2.6; 100 times

Question 53

An element is determined by the number of ____; elemental isotopes vary in the number of ____.

A) neutrons; electrons
B) protons; neutrons
C) neutrons; protons
D) protons; electrons

Question 54

Scientists discover a new fossil that they expect is at least three million years old. To estimate the age of the fossil they would most likely

A) search for layers of volcanic ash in rock layers above and below the location of the fossil.
B) use radiocarbon dating to determine the age of the fossil itself.
C) use radiocarbon dating to determine the age of the sedimentary layer in which the fossil was found.
D) all of the above

Question 55

Which of the following supports an ancient Earth?

A) the absence of short-lived isotopes in rocks
B) the presence of many short-lived isotopes in rocks
C) the absence of long-lived isotopes in rocks
D) none of the above

Question 56

Which of the following incorrectly matches the event with its age in the fossil record?

A) emergence of land plants 475 million years ago
B) oldest treelike plant, Wattieza - 385 million years ago
C) oldest fungi fossils - 440 million years ago
D) oldest land animal - 440 million years ago

Question 57

The earliest animal fossils appear similar to modern-day

A) sponges.
B) archaea.
C) fungi.
D) jellyfish.

Question 58

The earliest traces of life are found in which geological eon?

A) Archean
B) Hadean
C) Phanerozoic
D) Proterozoic

Question 59

Prokaryotes include representatives from

A) bacteria.
B) archaea.
C) eukarya.
D) a and b
E) a, b, and c

Question 60

Lord Kelvin believed that Earth was

A) a few thousand years old.
B) 300 million years old.
C) a few billion years old.
D) 20 million years old.

Question 61

The earliest land plants resemble

A) large coniferous trees.
B) forbs and grasses.
C) tree ferns.
D) mosses and liverworts.

Question 62

What are four features shared by all chordates?

Question 63

Match the following species or taxonomic groups with the approximate time period in which they appear in the fossil record.
$$\begin{array} { | l | l | } \hline \text { Bacteria } & 3.5 \text { bya } \\\hline \text { Mammals } & 150 - 200 \text { mya } \\\hline \text { Tetrapods } & 370 \text { mya } \\\hline \text { Flowering plants } & 132 \text { mya } \\\hline \text { Sponges } & 650 \text { mya } \\\hline\end{array}$$

Question 64

Describe the evidence of the early types of life on land.

Question 65

Compare and contrast the Ediacaran and Cambrian fauna.

Question 66

Describe three reasons why any given organism would be unlikely to be discovered in fossilized form.

Question 67

Describe an example fossils being used to reconstruct the behavior of extinct animals.

Question 68

Zircons are

A) tiny specks of carbon preserved for billions of years in minerals
B) large particles of carbon preserved for millions of years in underground deposits
C) molecular evidence of living organisms
D) a and c
E) b and c

Question 69

Explain how carbon isotopic signatures can be used to determine the diets of extinct organisms.

Question 70

Which of the following is a behavior that was discovered in the fossil record?

A) Turtles died while mating in a lake.
B) Ichthyosaurs gave birth to live offspring.
C) A fish died while feeding on a pterosaur.
D) all of the above
E) none of the above

Question 71

The earliest hints of terrestrial life come from

A) prokaryotes.
B) plants.
C) algae.
D) animals.

Question 72

The earliest signs of life 4.1 billion years ago exist in

A) fossilized bacterial mats called stromatolites.
B) isotopic signatures of zircons.
C) biomarkers from pigmented bacteria.
D) all of the above

Question 73

Which of the following may have been a more limiting factor for early life to form?

A) the toxic atmosphere
B) the amount of water available
C) the temperature
D) a and b
E) b and c

Question 74

Give one explanation that has been proposed for why grasses expanded and diversified around 20 million years ago.

Question 75

We are currently in the ____ epoch, which began _____ years ago.

A) Quaternary; 2.58 million
B) Cenozoic; 66 million
C) Holocene; 11,700
D) Phanerozoic; 541 million

Question 76

Describe one advantage that carbon dating provides over other types of radiometric dating.

Question 77

An isotope's half-life is

A) the amount of time that the isotope has been on Earth divided by two.
B) the length of time it takes for half of a sample of atoms to decay.
C) the number of protons and neutrons in an atom divided by two.
D) the ratio of unstable atoms to stable atoms in half a gram of sample.

Question 78

Explain the statement "It's a microbial world … and we just happen to live in it" in the context of both early and modern Earth.

Question 79

What factor might scientists take into account when choosing an isotope to date a new fossil?

Question 80

Describe the earliest pieces of evidence we have for life on Earth, including direct and indirect evidence.