Charles Darwin
Lamarck
Evidence for Evolution
Theory of Evolution
Types of Natural Selection
100
What was Charles Darwin's job and with what ship did he set sail?
He was the naturalist aboard the HMS Beagle
100
Who was Jean-Baptiste Lamarck? What did he think about how organisms changed over time?
French naturalist who thought that by selective use or disuse of an organ, organisms acquired or lost traits in their lifetime and these traits would be passed to their offspring.
100
What are Homologous structures?
Variation of a structure that are very similar anatomically but have a very different function. Occurs on closely related organisms.
100
What is fitness? What are adaptations? How do they relate?
Fitness is the ability of an individual to survive and reproduce in its environment. Adaptations are inherited characteristics that can be structural, anatomical, physiological, and sometimes behavioral. Adaptions increase fitness.
100
What type of Natural Selection occurs when individuals at one end of a bell curve have a higher fitness than individuals in the middle or other end?
Directional Selection
200
How did Darwin begin his ideas on evolution?
He studied animals in different locations and fossils that resembled organisms that existed in his time.
200
What are the three points of Lamarck's theory of evolution?
1. Tendency toward perfection, 2. Use and disuse of organs 3. Inheritance.
200
What are analogous structures?
Structures that are very different anatomically but have a similar function.
200
What did Darwin see as the struggle for existence?
Members of each species compete regularly for food, living space and other necessities of life.
200
What type of natural selection occurs when individuals near center of the curve have higher fitness than individuals on the ends?
Stabilizing Selection
300
What was Darwin's ideas about the age of the earth? What was the thought of the time? Whose ideas did he support?
Darwin thought the earth was millions of years old while most people of the time thought the earth was only a few thousand years old. He supported Hutton and Lyell.
300
What did tendency towards perfection mean in Lamarck's theory of evolution?
All organisms have an innate tendency toward complexity and perfection. Ex: Birds kept trying to fly and so their wings became more suited for flight.
300
What is comparative embryology?
Comparison of embryos to find a common ancestor
300
What is natural selection?
The driving force of Evolution. Nature selects individuals whose traits will allow them to survive. It is observed in populations - not individuals.
300
What type of natural selection occurs when individuals at either end of the curve have a higher fitness than those in the middle?
Disruptive Selection
400
Who was Thomas Malthus? What was his theory?
Economist in London in the 1800s. He thought that if the human population continued to grow unchecked, soon there would not be enough resources for everyone.
400
What did Lamarck mean by use or disuse of an organ?
Organisms could alter the shape or size of organs by using them in different ways. Ex: Crabs attract mates by large claw. So by 'growing' their claw larger, crabs could attract more mates.
400
A record of species that lived long ago is an example of what type of evidence for evolution?
Fossil Records
400
Why is evolution classified as a 'theory'?
Because it is an explanation of an observation well supported by data.
400
What happens to a population if disruptive pressure is strong enough?
Curve will split into two and two distinct phenotype will emerge.
500
How did Malthus's theory influence Darwin?
Darwin applied his idea to plants and animals that they produce more offspring because not all survive to reproduce.
500
What did Lamarck think about inheritance?
Lamarck thought that acquired traits could be passed down to offspring. Ex: If I work out and become muscular, my offspring will be muscular.
500
Organisms with closely related morpholgical features have more closely related molecular features is an example of what type of evidence?
Comparative Biochemistry?
500
What are Darwin's 5 points for the theory for evolution?
1. Populations have variations. 2. some variations are favorable. 3. More offspring are produced than survive. 4. Those that survive have favorable traits. 5. A population will change over time.
500
What happens to a single-gene trait that has no effect on fitness?
It will not be under pressure by natural selection and so the allele frequency will be random.
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