Topic 3

Question 1

What did people think of species before Darwin?

Answer 1

People noted that fossils usually didn’t look like living animals so they assumed that extinction must have occurred. The reasons for this varied such as supernatural, natural disasters, one species slowly changing into another and that things weren’t extinct just hiding

Question 2

What did Curvier think?

Answer 2

Species did not change over time but instead strata were due to catastrophes that caused extinction and new species would populate

Question 3

What did Lamarck think?

Answer 3

Species changed over time due to: Inheritance of acquired characteristics (a characteristic acquired during an organisms lifetime could be passed to its offspring)

Question 4

What did Darwin believe?

Answer 4

He believed in evolution by natural selection and decent with modification

Question 5

What is descent with modification?

Answer 5

The passing of traits from parent organisms to their offspring

Question 6

What were Darwin’s 3 inferences?

Answer 6

1. Organisms must compete for limited resources and not all succeed. 2. Some heritable variations are likely to provide individuals with a competitive advantage. 3. Individuals with advantageous variations are likely to leave more offspring then others

Question 7

Do Individuals evolve?

Answer 7

Populations evolve not individuals

Question 8

What is context dependency in Natural Selection?

Answer 8

There is not innate tendency for perfection, instead species evolve based on their context

Question 9

What is phenotypic variation?

Answer 9

Form, function and behavior

Question 10

What is genotypic variation?

Answer 10

Genetic make-up

Question 11

How does Natural Selection act on variation?

Answer 11

It must be expressed phenotypically and genotypically

Question 12

What are the sources for variation?

Answer 12

Mutation, Recombination, Independent assortment of chromosomes and fertilization

Question 13

What is a Slecetive Agent? What types are there?

Answer 13

A selective agent is a component of the natural environment that consistently causes differential survival or reproduction. The examples are biotic-living and abiotic-non-living

Question 14

What is the evidence for evolution?

Answer 14

Fossil Record, Homology, Direct Observations and Biogeography

Question 15

How does the fossil record support evolution?

Answer 15

Strata can be used to date fossils. In a strata forms are consistent. Intermediate forms can be identified that appear to be ancestors of current species. Extinction is seen in the record

Question 16

What is homology? How does it support evolution?

Answer 16

Similarity due to common ancestry. We can see this in comparative embryology evidence, vestigial structures and in molecular evidence

Question 17

What are transitional links?

Answer 17

The intermediate fossils that seem to be ancestors of current species

Question 18

How do vestigial structures support evolution?

Answer 18

Certain species have structures in their body that they do not need but can link them to common ancestors. Such as leg like structures in whales

Question 19

How does embryology support evolution?

Answer 19

When in the embryonic stage many species look very similar and have similar structures. This contributes to the idea that they share a common ancestor

Question 20

What is molecular evidence?

Answer 20

The universal genetic code is: DNA-amino acids-proteins

Question 21

What is direct observation?

Answer 21

The use of artificial selection, antibiotic resistance and the development of pesticide resistance are examples of direct observations

Question 22

What is artificial selection?

Answer 22

Selectively breeding organisms in order to gain a desired trait. It shows that evolution can be forced onto a species

Question 23

How does antibiotic resistance support evolution?

Answer 23

Bacteria show that they can evolve to no longer be effected by antibiotics

Question 24

How does development of pesticide resistance support evolution?

Answer 24

This shows that after all the pest that are not effected by pesticides are the only one to produce offspring for the next generating meaning the next generation is completely resistant to pesticides; they have evolved

Question 25

What is Biogeography?

Answer 25

Regions with “identical” climates have different species yet show convergence of form and function