Fundamental aspects of evolution

Question 1

What is macroevolution

Answer 1

patterns, trends and rates of change over

time

Question 2

What is Punctuated equilibrium

Answer 2

A hypothesis that explains the speed at which evolution occurs through natural selection.
Suggests that a rapid change in the characterics of a population may occur. Once the new population has adapted to the new environment (there are environmental changes), no further evolutionary changes will occur so characterics of population will remains at an equilibrium. there will be long periods of time where there is no change or very little change.
Punctuated by natural selection to bring about rapid changes in a short period of time followed by a long period of equilibrium.
Evidence- absence of transitional fossils indicating rapid change

Question 3

What is Darwinism

Answer 3

Speciation happens gradually. a species gradually changes slowly to form a new diverging from the original one

Question 4

Explain Darwin’s theory of natural selection in detail (mvetsrb)

Answer 4

(change in gene pool)
M-Many offspring is produced than an environment can sustain
V- variation amongst the offspring
E- Environment changes
T- Offspring with traits more suited to the change in enviroment and some don’t
S- Survival of the best suited offspring
R- Reproduction amongst offspring with suited traits when matured
B- their babies will inherit the suitable trait

Question 5

Give an example of Galapagos finches

Answer 5

m- More offspring finches are born than the environment can sustain
v- Variations amongst the finches BEAKS
e- environment changes, ancestor is on different islands therefore there will be different foods available (explain how the environment is different in detail according to the source)
t- Traits that are more suitable (give in detail what those traits are)
s- Survival amongst the sharper beak finches
r- reproduction amongst the surviving sharper break finches
b- offspring of the surviving finches with the desirable trait(sharper beaks) will inherit the desirable trait

Question 6

What is the outcome of natural selection

Answer 6

1- Organisms in a population become better adapted to their environment overtime
2- this causes the gene pool of the population to change over time
3- If the gene pool changes so much that individuals from the new population can no longer breed and produce fertile offspring with individuals from ancestral population then a new species has evolved. this process is called speciation

Question 7

Define artificial selection

Answer 7

Mimics natural selections. it involves people choosing a set of characteristics that are desirable and them breeding plants or animals to have those particular characteristics

Question 8

Give one example of artificial selection in domesticated animals e

Answer 8

Bonsmara cattle - crossed Nguni cattle which are well adapted to South African conditions but poor beef producers with imported British beef cattle (hereford) which produce good beef but aren’t suited to a hot environment

Question 9

give an example of domesticated plant

Answer 9

maize “teosinte” which is endemic to Mexico they were artificially interbreed with a sub species, zea maya to produce larger cobs