8th Grade Integrated Science Chapter 14 Lesson 1 on the Continental Drift Hypothesis. This is a short introduction to Alfred Weger and the current evidence used to support his theory. There is a short explanation of the fossil and rock evidence found. *This outline follows the Chapter 14.1 presentation slides.

1. Chapter 14 Lesson 1 – The Continental Drift Hypothesis – p494-500 – page 1
New Vocabulary
 Pangaea (495) – The supercontinent that all continents today were once a part of
 Continental Drift (495) – A hypothesis that suggests that continents are in constant motion on the surface of
Earth
Pangaea
 Each year, North America moves a few _____________________ farther away from Europe and closer to Asia.
 Nearly 100 years ago, Alfred _________________ began an important investigation to know whether Earth’s
continents were fixed in their positions.
o He proposed that all continents were once part of a supercontinent called ____________.
o Over time Pangaea began_________________ __________________, and the continents slowly
moved to their present positions.
 Wegener proposed the hypothesis of _____________________ drift, which suggested that continents are in
constant motion on the surface of Earth.
Evidence That Continents Move
 The most obvious evidence for continental drift is that the continents appear to fit together like pieces of a
__________________________.
 However, scientists were skeptical, and Wegener needed additional evidence
1. Apparent fit of the continents
2. Past ____________ Data
3. __________________ Correlation
4. _____________ and Mountain Correlation

2. Chapter 14 Lesson 1 – The Continental Drift Hypothesis – p494-500 – page 2
Climate Clues
 When Wegener pieced Pangaea together, he proposed that South America, Africa, India, and Australia were
located closer to ___________________________ 280 million years ago.
 He suggested the climate of the Southern Hemisphere was much ______________________ at the time.
o Glaciers covered most of these continents
 Wegener studied the _______________ deposited by glaciers in South America, Africa, India, and Australia.
 He discovered ________________ _______________, or deep scratches in rocks made as the glaciers moved
across the land on neighboring continents today.
Fossil Clues
 Animals and plants that lived on different continents can be ____________________ to that continent alone.
o Kangaroos are exclusive to___________________ . Lions live in ________________but not S. America.
o Because ____________________ separate continents, these animals cannot travel from one continent
to another by natural means
 However, _______________________of similar organisms have been found on several continents separated by
oceans.
 Fossils of a plant called Glossopteris have been discovered in rocks from South America, ______________,
India, Australia, and________________________.
 Evidence suggests these plants grew in a _____________________environment. Therefore, the climate of this
region, including Antarctica, was different than it is today.
o Antarctica had a warm and wet climate and changed drastically from _________ milllion years earlier
when glaciers existed.

3. Chapter 14 Lesson 1 – The Continental Drift Hypothesis – p494-500 – page 3
Rock Clues
 Wegener also observed that ________________________ ranges and rock formations on different continents
had common origins.
 Today geologists have determined that large-scale volcanic eruptions occurred on the western coast of
_________________ and the eastern coast of South America at about the same time hundreds of millions of
years ago
o These volcanic rocks are identical in both ____________________and ___________
 The _____________________ mountain range in northern Europe and the Appalachian Mountains in eastern
N. America are similar in age, structure, and composition.
 If you place the continents ______________________, these mountains would meet and form on long,
continuous mountain belt.
What is missing?
 Wegener continued to support the continent drift hypothesis until his death in ______________
 His ideas were not widely accepted until nearly 4 decades later, because he could not explain how they
________________.
 One reason scientists questioned continental drift was because it is a ______________ process
 It was not possible for Wegener to measure how ________________ the continents moved
o How could continents push their way through the ___________________rock of the sea floor?
o However at that time, the world was only beginning to understand what the seafloor looked like.
o It took many years after Wegener died before the evidence of plate tectonics hidden in the rifts on the
seafloor to be discovered.