Lab 1: Darwin & Natural Selection

Question 1

Anaximander, Xenophanes, and al-Jahiz

Answer 1

Scholars who theorized about evolution before Darwin

Question 2

Fitness

Answer 2

Avg. number of offspring produced by an organism compared to other organisms with different genotypes

Question 3

Genotype

Answer 3

Complete set of an organism’s genes

Combination of alleles for a given gene

Question 4

Adaptations

Answer 4

Gene-based trait whose frequency increases over time/generations AND whose presence results in a measurable advantage to the organism that possesses it

Question 5

Sexual Selection

Answer 5

Type of natural selection where opportunities to produce offspring are impacted by males competing to mate with females or females engaging in mate selection (on the bases of physical characteristics)

Question 6

Inheritance of acquired characteristics

Answer 6

the idea that if a parent developed a trait during its lifetime, it would be passed down to offspring)

Was disproved in an experiment where mice whose tails were hacked off we allowed to mate to see if offspring would be born tailess

Question 7

Charles Darwin

Answer 7

First to suggest that evolution occurred over time by natural selection (though the idea of evolution itself had been around since Greece)

Also recognized sexual selection (type of natural selection), artificial selection,

Question 8

Artificial Selection

Answer 8

When traits are selectively/intentionally passed down through deliberate breeding practices

Question 9

Gene

Answer 9

Basic unit of inheritance

Segments of DNA that code for specific protein products

Question 10

Thomas Malthus

Answer 10

Proposed (before Darwin) that exponential animal/human population growth would inevitably outpace linear resource growth resulting in war and famine

Contradicted the idea that all of the natural world was advancing towards divine perfection

Question 11

Struggle for Existence

Answer 11

Darwin’s idea (based on Thomas Malthus’ work) that only the most suitable specimens would be fit enough to compete successfully for resources and that others would perish.

Question 12

Phenotype

Answer 12

Observable, physical expression of an organism’s genotype

Question 13

Natural Selection

Answer 13

Darwin’s rationale for survival and increased reproduction opportunities of the fittest:

1. Organism variation is real
2. Variation is passed from parent to offspring
3. Many organisms produce far more offspring than will survive (differential reproductive success)

Question 14

Jean-Baptiste Lamarck

Answer 14

Theorized (before Darwin was born) that animals evolved by inheritance of acquired characteristics (the idea that if a parent developed a trait during its lifetime, it would be passed down to offspring)

Also believed things like poverty were inherited