UNIT 7 ck12’s 5.12-5.14 Flashcards
Who is one of the most famous scientists associated with the theory of evolution?
Charles Darwin
What are the two major ideas contained in Darwin’s theory of evolution?
- Evolution occurs
- Evolution occurs by natural selection
What is natural selection?
The process that results in living things with beneficial traits producing more offspring
What was the common belief about species before Darwin’s theories?
All species were created at the same time and remained unchanged
How old did people believe the Earth was during Darwin’s time?
About 6,000 years old
What significant event in Darwin’s life contributed to his ideas on evolution?
His voyage on the HMS Beagle
What was Darwin’s role on the HMS Beagle?
He was the naturalist
What was Darwin’s job as a naturalist on the Beagle?
To observe and collect specimens of plants, animals, rocks, and fossils
How long was Darwin’s trip on the Beagle?
5 years
Darwin spent over 3 years exploring during this trip.
What type of environments did Darwin visit that impressed him?
Tropical rainforests and new habitats
He observed many plants and animals he had never seen before.
What significant geological event did Darwin experience during his voyage?
Earthquake that lifted the ocean floor 2.7 meters
This indicated dramatic changes in continents and oceans over time.
What did Darwin find in mountains high above sea level?
Rocks containing fossil sea shells
These observations suggested that geological features change over time.
What did Darwin’s observations of rock ledges suggest?
Slow, steady processes change Earth’s surface
He noted that these ledges had once been beaches.
What type of fossils did Darwin dig up?
Fossils of gigantic extinct mammals
An example is the ground sloth, indicating past organisms were very different.
What are the Galápagos Islands?
A group of 16 small volcanic islands located 966 kilometers (600 miles) off the west coast of Ecuador, South America.
How do the individual Galápagos islands differ from one another?
They differ in terms of rockiness, dryness, soil quality, and rainfall.
What is a unique characteristic of the giant tortoises on the Galápagos Islands?
Some have saddle-shaped shells while others have dome-shaped shells.
What concept did Darwin begin to ponder due to his observations of the tortoises?
The origin of species.
Who was Jean Baptiste Lamarck?
An important French naturalist who proposed that species change over time
Lamarck’s idea of the inheritance of acquired characteristics is incorrect; traits developed during an organism’s lifetime cannot be passed to offspring.
What was Lamarck’s incorrect idea?
Inheritance of acquired characteristics
Lamarck believed that traits developed during an organism’s lifetime could be passed on to its offspring.
Who was Charles Lyell?
A well-known English geologist
Darwin took Lyell’s book, Principles of Geology, with him on the Beagle.
What did Charles Lyell argue in his book?
Gradual geological processes have shaped Earth’s surface
Lyell inferred that the Earth must be far older than most people believed.
Who was Thomas Malthus?
An English economist who wrote an essay titled On Population
Malthus argued that human populations grow faster than the resources they depend on.
What was the main argument of Malthus’s essay On Population?
Human populations grow faster than resources, leading to famine and disease
This keeps populations in check by killing off the weakest members.
