Lecture 3

Question 1

what is science

Answer 1

a process of generating knowledge

Question 2

what is the process of generating knowledge

Answer 2

observation
hypothesis
data collection 
experimentation
conclusions?

Question 3

what must a scientific theory be

Answer 3

a scientific theory is a falsifiable explanation derived from the scientific process

Question 4

what is a theory

Answer 4

theory is the best possible explanation at the time and based on the experiments done/data collected

Question 5

who was Erasmus Darwin (1731-1802)

Answer 5

A freethinking physician and poet, he wrote widely on the natural sciences and medicine
He subscribed to a concept of transmutation, which he believed resulted from inheritance of derived traits
He likely impacted his grandson’s thinking on inheritability

Question 6

where did darwin first go to school

Answer 6

University of Edinburgh in Scotland for medicine- but he didn’t like it

Question 7

where did darwin go to school after

Answer 7

Cambridge where he began studying for the ministry– but he didn’t like that much either

Question 8

what sparked darwins interest in evolution

Answer 8

Darwin starts collecting beetles

Question 9

why is William Paley (1743-1805) important

Answer 9

Darwin read and admired Paley’s seminal work, Natural Theology
Highly influential in his day, Paley’s work was empirically grounded, yet religious in nature
Watchmaker analogy = design implies a designer

Question 10

why is John Stevens Henslow (1796-1861) important

Answer 10

a professor of botany at Cambridge, he was a major influence on Darwin, and served as a mentor for many years
The two regularly set out on specimen-hunting excursions to the local countryside

Question 11

what was the initial purpose of darwin’s voyage

Answer 11

to conduct an extensive hydrographic survey of Patagonia, Tierra de Fuego and Chile

Question 12

During the voyage, Darwin began to consider two key geological questions
what were they about

Answer 12

1. the relationship between volcanism and seismic activity

2. the relative ages of mountain ranges and rock formations

Question 13

In addition to living plant and animal specimens, Darwin collected what

Answer 13

the bones of a number of extinct species

Question 14

did darwin actively look to prove a theory

Answer 14

It is important to note that Darwin was not actively building a theory of transmutation during the Beagle voyage. By 1836, he had some well-developed geological theories, but evolution by natural selection would – appropriately enough – develop slowly over several years

Question 15

During this time, Darwin would reflect on two key conclusions he’d drawn from his time on the Beagle, what were they

Answer 15

1. in nature, there is fierce competition for resources

2. minute differences among individuals maybe advantageous

Question 16

what type of work did darwin first publish

Answer 16

He published and presented on his geological findings, but not on his theories of transmutation (evolution)

Question 17

what was this was the foundation of natural selection as a theory

Answer 17

Darwin’s 1837 sketch outlined his theory of all life’s descent from an original ancestor
Though the details would not be worked out for some years, this was the foundation of natural selection as a theory

Question 18

who was Alfred Russel Wallace (1823-1913)

Answer 18

An English naturalist, he conducted years of fieldwork in Brazil and the Malay Archipelago
He independently devised a theory of natural selection
Without his knowledge, his research —along with Darwin’s—was presented to the Linnean Society of London in 1858

Question 19

when was On the Origin of Species by Means of Natural Selection published

Answer 19

One year after the joint paper with Wallace was presented at the Linnean Society of London, Darwin published On the Origin of Species by Means of Natural Selection (1859)
It was immediately popular and controversial

Question 20

what are the 6 Principles of Natural Selection

Answer 20

Overproduction
Competition
Variation
Adaptation
Natural selection
Speciation

Question 21

what is Overproduction

Answer 21

An organism’s potential rate of reproduction is higher than the rate of food and resource production

Question 22

what is Competition

Answer 22

There is a struggle for survival

Question 23

what is variation

Answer 23

Variations exist within a population

Question 24

what is adaptation

Answer 24

Variations can be favourable and may offer a selective advantage (Adaptation)
the white and black moth example during the industrial revolution

Question 25

what is natural selection

Answer 25

Those best suited to their environment survive and have more offspring and so will be better represented in the next generation

Question 26

what is speciation

Answer 26

With enough accumulated differences, a new species may arise

Question 27

that is needed in order for something to be considered “fit”

Answer 27

Reproductive Success

Question 28

what did the Galapogos Finches help darwin to conclude

Answer 28

Natural selection does not always result in unidirectional change

Question 29

what are the Types of Variation

Answer 29

Continuous variation

Discontinuous variation

Question 30

what is Discontinuous variation

Answer 30

involves “either-or traits” that are confined to set categories and do not fall on a continuum

Discontinuous variation is usually not a significant factor in evolutionary adaptation

Question 31

what is Continuous variation

Answer 31

is variation with a relative value on a continuum between extremes. Height is an example, as is hand span, shoe size, weight, skin color, etc

Question 32

what are Complex Adaptations

Answer 32

The development of complex mechanisms such as the eye is the result of continuous variation, with multiple intermediate steps

Question 33

Natural Selection will take place ONLY if:

Answer 33

the trait is heritable
the trait displays variation among individuals
the trait must be subject to selective pressure

Question 34

What are selective pressures?

Answer 34

Competition for food/energy

Competition for a mate**
important to note… some features do not have anything to do with the environment… it is just to help attract and mate to pass not heir genes

Environmental changes

Predators

Parasites

Question 35

Darwin believed in “blending inheritance”, what is that

Answer 35

where characteristics from each parent mixed like liquids

Question 36

what was one thing that darwin got wrong

Answer 36

blending inheritance

Question 37

who proved blending inheritance wrong

Answer 37

In 1867, Fleeming Jenkin showed statistically that with blending inheritance, single favorable mutations would be diluted out of existence over time

Question 38

what didn’t darwin know

Answer 38

1. What is the source of individual variation?

2. How are characteristics inherited?