Evolution

Question 1

Charles Darwin (background info)

Answer 1

Influenced by Charles Lyell’s “Principles of Geology” -> uniformitarianism
Studied sedimentary rocks and fossils in Patagonia (Argentina)
Observed biota of various island chains -> Galapagos

Question 2

Alfred Russel Wallace (background info)

Answer 2

Self-taught, left school at 13
Inspired by previous explorers, went to study nature in Brazil
Traveled to South America and Asia to study how geography affected the range of species
Corresponded with Darwin in 1858

Question 3

What did both Darwin and Wallace observe?

Answer 3

Patter: organisms only live in environments to which they are well-adapted
Hypothesized process: Environmental factors prevent any organism that is NOT well-adapted from successfully reproducing (Natural Selection)

Question 4

On the Origin of Species (book)

Answer 4

Published in 1859, sold out almost instantly, and met with critical acclaim and violent opposition
Darwin worked on the theory for the book for over 20 years.

Question 5

Darwin’s theory of evolution

Answer 5

• Variation exists among individuals within a population
• This variation is heritable
• The organisms whose variation best fits them to the environment are the ones most likely to survive, reproduce, and pass those desirable traits on to the next generation
• Variation provides the raw material for natural selection to act on
• Natural selection - observable way for life to change

Question 6

Genetic basis of evolution

Answer 6

Traits (such as colour) are coded for by deoxyribonucleic acid (DNA) which join together to form genes, which are linked to form chromosomes

Question 7

What is evolution

Answer 7

Differential reproductive success of genes within a population

Question 8

What is natural selection

Answer 8

This process of passing on “successful” traits to subsequent generations

Question 9

What is genetic inertia

Answer 9

It refers to how long it takes for a trait to become popular within a population. The longer it takes the greater the inertia.

Question 10

How does population size effects evolution

Answer 10

Small populations are able to evolve more rapidly but there is also less variety within the population so they are more vulnerable to rapid extinction

Question 11

What is convergent evolution and give an example

Answer 11

It is when two populations evolve independently but end up with similar traits an example being sharks and dolphins

Question 12

What is a species

Answer 12

Members of a population who can breed and produce viable offspring

Question 13

How do you differentiate species in the fossil record

Answer 13

By basing species on morphology (shape)

Question 14

How do you track biodiversity in the rock record

Answer 14

Sum the total taxa

Question 15

What would be considered a mass extinction

Answer 15

When the rate of extinction increases and overwhelms origination rate

Question 16

How does genetic variability stay maintained in populations?

Answer 16

Sexual reproduction - constant recombination of genetic material within a population (new combinations every generation)
Asexual reproduction - mutations (can also help provide genetic variation within a population, resulting in evolution over time); examples: deletions, duplications, inversions.