Paleontology

Question 1

What is continental drift?

Answer 1

The gradual movement of the continents across the earth’s surface through geological time.

This movement is evidenced by scars on the ocean floor.

Question 2

Who introduced the Theory of Continental Drift and when?

Answer 2

Alfred Wegener introduced the theory in 1912.

The theory gained wider acceptance in the 1960s.

Question 3

What was the revolutionary aspect of the Theory of Continental Drift?

Answer 3

It changed the understanding of species and their distribution globally.

The theory explained the former connection of continents and species.

Question 4

What is Pangaea?

Answer 4

A supercontinent that existed approximately 335 million years ago and began to break apart about 175 million years ago.

Pangaea was centered on the Equator.

Question 5

What geological mechanism explains continental drift?

Answer 5

Plate tectonics.

This mechanism describes the movement of the plates below Earth’s surface.

Question 6

During which eras did Pangaea exist?

Answer 6

Late Paleozoic and early Mesozoic eras.

Pangaea was surrounded by the super-ocean Panthalassa.

Question 7

What was Gondwana?

Answer 7

A large landmass that existed from 450 to 120 million years ago.

Gondwana was part of Pangaea before splitting from Laurasia.

Question 8

List the continents included in Gondwana.

Answer 8

• South America
• Africa
• India
• Antarctica
• Australia

Gondwana started to split up around 150 million years ago.

Question 9

True or False: Pangaea was the first supercontinent to exist.

Answer 9

False.

Pangaea is the most recent supercontinent.

Question 10

How does understanding continental drift contribute to our knowledge of evolution?

Answer 10

It reveals how species were once connected on the same landmass but later became isolated.

This isolation led to the evolution of distinct species and ecosystems.

Question 11

What is biogeography?

Answer 11

The study of the distribution of species and ecosystems in geographic space and through geological time.

Biogeography helps understand how living organisms have evolved to adapt to different environments.

Question 12

How does continental drift relate to biogeography?

Answer 12

It helps understand the distribution of living organisms and how they evolved due to geological events.

Geological events influenced the migration and diversification of species.

Question 13

What is the significance of studying biogeography?

Answer 13

It provides knowledge for understanding the history of life on Earth.

Understanding past geological events is crucial for tracing species evolution.

Question 14

What are Ratite birds?

Answer 14

Flightless birds descended from a single ancestor that lived across Gondwana.

Ratites evolved independently after the separation of land masses.

Question 15

Why are Ratite birds only found on southern continents?

Answer 15

Because they evolved independently after the land masses of Gondwana separated.

Their distribution is a result of historical geological events.

Question 16

What anatomical feature distinguishes Ratite birds from other flightless birds?

Answer 16

They have no keel on their sternum.

The lack of a keel prevents them from flying even if they had suitable wings.

Question 17

What are fossils?

Answer 17

Remains, impressions, or traces of ancient life forms preserved in the Earth’s crust.

Fossils provide a direct record of ancient life and evolution.

Question 18

What are the different types of fossils?

Answer 18

True form, trace, mould, and cast fossils.

Each type provides different insights into ancient life.

Question 19

What are true form fossils?

Answer 19

Fossils made of an actual plant or animal, preserved through permineralisation.

True form fossils consist of hard parts like bones or stems.

Question 20

What is permineralisation?

Answer 20

The process where organic compounds are replaced molecule by molecule with inorganic minerals.

This process can lead to the petrification of organisms.

Question 21

What are trace fossils?

Answer 21

Fossils that record the behaviors and movements of animals, such as footprints and nests.

They provide insights into the lifestyle of ancient organisms.

Question 22

How is a mould fossil formed?

Answer 22

By leaving a hollow impression of a plant or animal in sediment.

The surrounding sediment hardens around the organism before decomposition.

Question 23

What is a cast fossil?

Answer 23

A natural occurring replica formed when sediment fills in a hollow mould fossil.

Cast fossils provide a three-dimensional representation of the original organism.

Question 24

What are the four key conditions necessary for fossil formation?

Answer 24

• The organism must die in a suitable location with little oxygen
• The carcass must be rapidly buried
• Permineralisation must occur over time
• The fossil must be exposed by erosion and discovered before it erodes

These conditions prevent decomposition and allow for the preservation of the organism as a fossil.

Question 25

What is the purpose of dating fossils?

Answer 25

To place absolute dates on the geological record and understand the history of life on Earth

This helps scientists discover when different species lived and provides evidence for evolution.

Question 26

What does relative dating of fossils rely on?

Answer 26

The order of sedimentary deposition

Older fossils are typically found deeper in sedimentary rocks.

Question 27

What are index fossils?

Answer 27

Organisms that were widespread, common, and lived during a specific time

They are used to compare locations and calibrate different sedimentary layers.

Question 28

What is radiometric dating?

Answer 28

A type of absolute dating that uses radioactivity to determine the age of rock layers or fossils

It involves measuring the decay of unstable elements into stable ones.

Question 29

What is half-life in the context of radioactive isotopes?

Answer 29

The time it takes for half the mass of a radioactive element to decay into its decay product

Different isotopes have different half-lives, making them useful for various dating applications.

Question 30

What are missing links in paleontology?

Answer 30

Organisms that show intermediate characteristics between old and new groups

They are hypothesized organisms that can help fill gaps in the evolutionary record.

Question 31

What are transitional forms?

Answer 31

Fossils of previously hypothesized missing links that provide evidence for evolution

Their discovery is often a significant event in the scientific community.

Question 32

What evidence does the discovery of Ambulocetus provide?

Answer 32

Understanding the evolution of cetaceans (dolphins and whales)

Ambulocetus is considered a significant transitional form in whale evolution.

Question 33

What does the discovery of Archaeoptery contribute to?

Answer 33

Understanding the evolution of aves (birds)

Archaeopteryx was a dinosaur with bird-like features, bridging the gap between reptiles and birds.

Question 34

What is Thrinaxodon?

Answer 34

A tetrapod with both reptile and mammal-like features

Thrinaxodon is significant in the study of mammal evolution.

Question 35

What are tetrapods?

Answer 35

Vertebrates with four limbs, including amphibians, reptiles, birds, and mammals

Tetrapods evolved from a common ancestor that was a fish with lobed fins.

Question 36

What are ‘living fossils’?

Answer 36

Organisms belonging to groups previously known only from the fossil record

They resemble ancient fossil specimens and are likely their living descendants.

Question 37

What characteristics do coelacanths display?

Answer 37

Primitive tetrapod-like characteristics, specifically lobed fins

Coelacanths were known only from the fossil record until a living specimen was found in 1938.

Question 38

When were coelacanths known only from the fossil record?

Answer 38

360-65 million years ago

The first living specimen was caught in 1938.

Question 39

What was Ginkgo once known for in the fossil record?

Answer 39

A globally distributed group of plants represented by many species

Ginkgo is notable for its historical distribution.

Question 40

What is the significance of fossil tourism in South Africa?

Answer 40

An important source of income and employment in fossil-rich areas

It attracts both international paleontologists and tourists.

Question 41

What is the Cradle of Humankind?

Answer 41

A World Heritage Site in Gauteng, South Africa, known for significant fossil discoveries

It includes sites like Sterkfontein, Swartkrans, and Kromdraai.

Question 42

Name two significant fossils found in the Cradle of Humankind.

Answer 42

• Mrs Ples
• Little Foot
• Karabo Child (2008)

These fossils have contributed greatly to our understanding of human origins.

Question 43

What is ‘Maropeng’?

Answer 43

The Tswana word for ‘origins’ and a tourist centre near the Cradle of Humankind

It plays a role in educating visitors about human evolution.

Question 44

Name three other areas in South Africa rich in fossils.

Answer 44

• Langebaan
• Border Cave
• Karoo area

These areas also attract tourists and contribute to local economies.

Question 45

How can local South Africans benefit from fossil tourism?

Answer 45

By working as tour guides, hotel staff, game rangers, drivers, curio sellers, etc.

It is essential for local communities to view these sites as economic opportunities.

Question 46

True or False: Fossil sites are only of academic interest and have no relevance to local communities.

Answer 46

False

Local communities can find employment and income through fossil tourism.