Question 1

Most dinosaurs were extinct by ____ years ago.
A) 10,000
B) 1 million
C) 500 million
D) 65 million
E) 1 billion

Accepted Answer

Most dinosaurs became extinct approximately 65 million years ago, at the end of the Cretaceous Period, marking the Cretaceous-Paleogene extinction event.

Question 2

Which element is least useful for dating fossils greater than 10 million years old?
A) Carbon-14
B) Uranium-238
C) Uranium-235
D) Thorium-232
E) Rubidium-87

Accepted Answer

Carbon-14 has a half-life of about 5,730 years, making it useful for dating relatively recent fossils but not those over 10 million years old, as it would have decayed away to undetectable levels by then.

Question 3

If the entire history of the Earth is symbolized by a 12-month calendar, dinosaurs and mammals both appear in the month of ____.
A) August
B) September
C) October
D) November
E) December

Accepted Answer

Using the calendar analogy to represent Earth's history, dinosaurs first appeared around late December (approximately December 15-20), and mammals also first appeared in December, though earlier than dinosaurs. This analogy compresses the Earth's 4.6 billion-year history into a single year to help illustrate the relative timing of events in Earth's history. Dinosaurs and mammals both appearing in December highlights how recent their appearances are in the grand timeline of Earth's history.

Question 4

Fossils are predominantly found in ____.
A) metamorphic rocks
B) igneous rocks
C) sedimentary rocks
D) crystalline rocks
E) radioactive rocks

Accepted Answer

Fossils are predominantly found in sedimentary rocks because these rocks form from the accumulation of sediment, which can bury and preserve organic material. Metamorphic and igneous rocks undergo processes that typically destroy organic remains, while the term "crystalline rocks" can refer to both igneous and metamorphic rocks, and "radioactive rocks" is not a classification used in the context of fossil preservation.

Question 5

The first dinosaur fossils were discovered in ____, leading to the first public dinosaur craze.
A) Britain
B) Australia
C) United States
D) South Africa
E) China

Accepted Answer

The first dinosaur fossils that led to the public dinosaur craze were discovered in Britain in the early 19th century. This marked the beginning of paleontology as a scientific discipline and captured the public's imagination.

Question 6

The time interval used to measure the absolute age of rocks by radiometric dating is called the ____.
A) radioisotope unit
B) radiometric unit
C) radiometric life
D) radioisotope life
E) half-life

Accepted Answer

The correct term is "half-life," which refers to the time required for half of the radioactive atoms in a sample to decay. This concept is fundamental in radiometric dating to determine the absolute age of rocks and fossils.

Question 7

Over time, the carbon isotope¹⁴C decays into ____. A) 12C B) 14N C) 12N D) 13C E) 12B

Accepted Answer

Carbon-14 (14C) decays into nitrogen-14 (14N) through beta decay, where a neutron is converted into a proton, an electron, and an antineutrino, changing the element from carbon to nitrogen.

Question 8

Angiosperms first appeared during the ____ period.
A) Cambrian
B) Jurassic
C) Cretaceous
D) Neogene
E) Devonian

Accepted Answer

Angiosperms, or flowering plants, first appeared during the Cretaceous period, which is known for the diversification of flowering plants.

Question 9

Most dinosaurs died out by the end of the ____ period.
A) Triassic
B) Jurassic
C) Cretaceous
D) Quaternary
E) Permian

Accepted Answer

Most dinosaurs became extinct by the end of the Cretaceous period, which is the last period of the Mesozoic Era, approximately 66 million years ago.

Question 10

According to the geological time scale, which segment of Earth's history is the oldest?
A) Hadean eon
B) Archean eon
C) Proterozoic eon
D) Paleozoic era
E) Cenozoic era

Accepted Answer

The Hadean eon is the oldest segment of Earth's history, dating from the formation of the Earth about 4.6 billion years ago to about 4 billion years ago.

Question 11

During the Cretaceous period, ____.
A) mammals diversified and flourished
B) life appeared on this planet
C) the first animals with shells and skeletons appeared
D) the dinosaurs reached their peak and then most species became extinct
E) the first human-like apes appeared

Accepted Answer

During the Cretaceous period, dinosaurs reached their peak in diversity and abundance, but by the end of the period, most dinosaur species became extinct due to a mass extinction event.

Question 12

Mammals underwent an evolutionary "explosion", or major adaptive radiation, during the ____.
A) Mesozoic era
B) Cambrian period
C) Triassic period
D) Devonian period
E) Cenozoic era

Accepted Answer

Mammals underwent a major adaptive radiation during the Cenozoic era, following the extinction of the non-avian dinosaurs at the end of the Cretaceous period. This allowed mammals to fill ecological niches that were previously occupied by dinosaurs, leading to a significant diversification in their forms and habitats.

Question 13

The earliest signs of life appeared on Earth during the ____.
A) Archean
B) Paleozoic
C) Mesozoic
D) Cambrian
E) Cenozoic

Accepted Answer

The earliest signs of life on Earth are found in rocks dating back to the Archean Eon, which began about 4 billion years ago, significantly earlier than the other periods listed.

Question 14

Which group of animals are living representatives of the theropods, a lineage of bipedal predatory dinosaurs?
A) birds
B) crocodiles and alligators
C) snakes and lizards
D) turtles
E) mammals

Accepted Answer

Birds are the only living descendants of theropods, which were a group of bipedal predatory dinosaurs. This connection is supported by numerous anatomical and genetic similarities.

Question 15

Dinosaurs flourished during the ____ era.
A) Archaean
B) Paleozoic
C) Mesozoic
D) Cambrian
E) Cenozoic

Accepted Answer

Dinosaurs flourished during the Mesozoic era, which is often referred to as the "Age of Reptiles." This era spanned from about 252 to 66 million years ago and is divided into three periods: Triassic, Jurassic, and Cretaceous.

Question 16

A paleontologist estimates that when a particular rock formed, it contained 12 mg of the radioactive isotope potassium-40, which has a half-life of 1.25 billion years. The rock now contains 3 mg of the isotope. About how old is the rock?
A) 2.5 billion years
B) 5.0 billion years
C) 1.25 billion years
D) 0.3 billion years
E) 0.4 billion years

Accepted Answer

The rock has gone through two half-lives to reduce from 12 mg to 3 mg (12 mg to 6 mg in the first half-life, and then 6 mg to 3 mg in the second half-life). Since each half-life is 1.25 billion years, two half-lives equal 2.5 billion years.

Question 17

The analysis of large-scale changes in morphology and diversity over life's 3.8-billion-year history comprises the study of ____.
A) microevolution
B) mutation
C) macroevolution
D) artificial selection
E) genetic drift

Accepted Answer

Macroevolution refers to the broad pattern of evolution above the species level, encompassing the grand scale of change that results in the emergence of new species and other taxonomic groups, as well as the extinction of species, over long periods of time. This includes the study of large-scale changes in morphology and diversity throughout the history of life on Earth.

Question 18

Which adaptation is least likely to be found in any dinosaurs?
A) bright coloration
B) bipedal posture
C) feathered wings
D) gills for breathing underwater
E) posture with heads upright and tails off the ground

Accepted Answer

Dinosaurs, being terrestrial animals, would not have evolved gills for breathing underwater as this is an adaptation found in aquatic animals.

Question 19

The radioactive decay of carbon-14 can be used to determine ____.
A) relative dating
B) absolute dating
C) mutation rates
D) plate tectonics
E) extinction rates

Accepted Answer

Carbon-14 dating is a method used to determine the absolute age of an object containing organic material by using the properties of radiocarbon, a radioactive isotope of carbon.

Question 20

Radiometric dating works best with ____.
A) sedimentary rocks
B) limestone
C) metamorphic rock
D) volcanic rocks
E) meteorites

Accepted Answer

Radiometric dating works best with volcanic rocks because they contain minerals that crystallize from molten material, providing a reliable record of the time of formation.

Quiz 23: Paleobiology and Macroevolution

Most dinosaurs were extinct by ____ years ago.

Which element is least useful for dating fossils greater than 10 million years old?

If the entire history of the Earth is symbolized by a 12-month calendar, dinosaurs and mammals both appear in the month of ____.

Fossils are predominantly found in ____.

The first dinosaur fossils were discovered in ____, leading to the first public dinosaur craze.

The time interval used to measure the absolute age of rocks by radiometric dating is called the ____.

Over time, the carbon isotope14C decays into ____.

Angiosperms first appeared during the ____ period.

Most dinosaurs died out by the end of the ____ period.

According to the geological time scale, which segment of Earth's history is the oldest?

During the Cretaceous period, ____.

Mammals underwent an evolutionary "explosion", or major adaptive radiation, during the ____.

The earliest signs of life appeared on Earth during the ____.

Which group of animals are living representatives of the theropods, a lineage of bipedal predatory dinosaurs?

Dinosaurs flourished during the ____ era.

A paleontologist estimates that when a particular rock formed, it contained 12 mg of the radioactive isotope potassium-40, which has a half-life of 1.25 billion years. The rock now contains 3 mg of the isotope. About how old is the rock?

The analysis of large-scale changes in morphology and diversity over life's 3.8-billion-year history comprises the study of ____.

Which adaptation is least likely to be found in any dinosaurs?

The radioactive decay of carbon-14 can be used to determine ____.

Radiometric dating works best with ____.

Over time, the carbon isotope¹⁴C decays into ____.