Lecture 1- development of evolutionary though

Question 1

what did Aristotle believe? (300bc)

Answer 1

that life was spontaneously generated

Question 2

explain of Francesco Redis(1668) experiment

Answer 2

• redi tested Aristotle’s theory that life on earth was spontaneously generated
• he experimented with jars of covered and uncovered meat
• a few weeks after setting up the experiment, he found flies and maggots on the uncovered meat

Question 3

what were the finding of Francesco Redi’s 1668 experiment?

Answer 3

there was maggots on the uncovered meat. this shows that life came from existing life (as the flies had laid their eggs, thus generating the maggots) and that concluded life was not spontaneous.

Question 4

Did francesco Redi accept or reject Aristotle’s theory?

Answer 4

Rejected, as he stated that life was not spontaneous

Question 5

What was Aristotle’s scale of nature consistent with?

Answer 5

the old testament account of creation, that species were created by god and are therefore perfect

Question 6

why is Carl Linnaeus significant? (1707-1778)

Answer 6

he was a Swedish naturalist. He created a two part binomial format for naming species.

Question 7

what type of classification system did Carl Lineaus create?

Answer 7

He created a nested classification system, grouping similar species into similar categories. Eg.linking in the same genus

Question 8

What is carl linaeus’ binomial classifcation system?

Answer 8

scientific names have a genus and a species name (eg. Homo Sapien)

Question 9

what did Linnaeus ascribe resemblance between species to?

Answer 9

the pattern of creation, NOT evolutionary kinship

Question 10

How did darwin expand on Linnaeus binomial system?

Answer 10

he argued that classification should be noted on evolutionary relationships, and noted that organisation on the Linnaean system often reflected these relationships (they looked similar as they had similar characteristics from a common ancestor)

Question 11

Explain George Curviers stance on evolution and extinction (1769-1832)

Answer 11

• Curvier noted that the older the rock strata, the more dissimilar the found organism were to current forms
• some species appeared and disappeared between layers
• he then inferred that each boundary between stratamarked a sudden catastrophic event causing extinction, and that new species repopualted the areas after
• he STAUNCHLY rejected evolution as a cause for these changes

Question 12

How did darwin contribute to evolutionary theory?

Answer 12

• wrote the origin of species by means of natural selection in 1859
• proposed the theory of natural selection as the main cause of evolution

Question 13

explain the theory of evolution via natural selection

Answer 13

• induvidual plants and animals show variation
• this variation is HERITABLE, and is passed on partially to offspring
• there is competition for limited resources within an environment, and this is a limiting factor
• the limiting factor results in competition
• competition causes selection.the magnitude and presence of favourable traits influences whether the outcome of competition, and whether the organism lives or dies.
• those who survive pass favourable genes onto the population, and these gradual change and adaptation of form and function of traits within a population

Question 14

how do traits influence the outcome of natural selection?

Answer 14

traits influence how well adapted an organism is to its environment. the presence and magnitude influences the outcome of competition, and whether the organism survives to reproduce

Question 15

Explain the process by which darwin discovered natural selection

Answer 15

• on the voyage of the beagle (1831) he observed finches on the Galapogas Islands
• he obserbved birds on different islands with different characteristics depending in their food source
• all of darwins finches had evolved in different environments, and subsequently undergone adaptive radiation within them

Question 16

what were the differences in beaks that darwin noted on?

Answer 16

• birds with seeds and nuts as their main food source had big beaks
• birds with narrow beaks accessed their food from tree trunks

Question 17

what is adaptive radiation?

Answer 17

the process by which organisms diversify rapidly from an ancestral species to a multitude of new forms, in response to new ecological niches

Question 18

who thought of the theory of evolution independently of Darwin?

Answer 18

alfred russel wallace

Question 19

who argued that selection acts on individuals?

Answer 19

George williams

Question 20

what did George Williams argue?

Answer 20

that selection acts on individuals, and populations are where this change can be measured

Question 21

why was Charles Lyell significant?

Answer 21

He published principles of geology, which essentially stated that the earth was millions of years old to allow for the formation of geological structures. This supported Darwins work, as it showed that the earth was old enough for the timescale of evolution to occur

Question 22

why was Thomas Malthus significant? what did he write?

Answer 22

he wrote the essay entitled: “essay on the principle of population”. he stated that reproduction is potentially faster than food production, but due to competition it never truly is

Question 23

what were darwins two problems when proposing his theory of evolution?

Answer 23

• the age of the earth was though to only be 6000 years old (based on the bible) which didn’t provide an appropriate time scale for evolution
• he knew nothing about the genetic components for variability