Evolution

Question 1

4 basis of natural selection

Answer 1

1) heritable variation
2) competition for resources
3) reproductive success varies
4) organisms adapt with environment

Question 2

Mechanisms for modification

Answer 2

Gene variation
Pressure at individual level

Question 3

Gene

Answer 3

Unit of heredity
Passed from partner to offspring

Question 4

Genetic fitness

Answer 4

Individuals ability to reproduce relative to others.
More for= ability to spread more genes

Question 5

Adaptation

Answer 5

Evolve trait better visited to environment. Result of natural selection.

Question 6

Traits between two species link them together. Share a common ancestor

Answer 6

Transitional species

Question 7

Linked fish and amphibians

Answer 7

Tetrapods

Question 8

Similar structures
inherited from common ancestor

Answer 8

Homologous structures

Question 9

Similar structures
Originated independently

Answer 9

Analogous structures

Question 10

Structure important for ancestor
Remains in derived species

Answer 10

Vestigial structures

Question 11

Antibiotic resistant bacteria

Answer 11

Staphylococcus aureus
Penicillin and methicillin resistant

Question 12

Biogeographic evidence

Answer 12

Similarities in global strata
All continents were connected and split apart

Question 13

Marsupials in Australia

Answer 13

Egg laying- marsupial pouch- placenta
Placental mammals outcompeted marsupials in South America.

Question 14

Species definition

Answer 14

Group of same kind of organism in a population
May breed to produce viable offspring
Do not breed with other kinds

Question 15

Speciation

Answer 15

Formation of two species from one

Question 16

Allopathic speciation

Answer 16

Geographic isolation. Physical barrier
Adaptive radiation

Question 17

Sympatric specidtion

Answer 17

Within same area
Gene flow
Sexual selection
Habitat differentiation

Question 18

Gene flow types

Answer 18

Polyploidy: >2 chromosome copies
Autopolyploid: cell division error. Tetraploid cells. Self pollination
Allopolyploid: Asexual reproduction. Interbreeding with sterile hybrids.

Question 19

Pre-zygotic barriers

Answer 19

Temporal
Habitat
Behavioral
Mechanical
Gametic

Question 20

Habitat isolation

Answer 20

Pre zygotic Limit mating
2 species with 2 habitats within same area. Rare encounters

Question 21

Temporal isolation

Answer 21

Pre-zygotic prevents mating
Seasonal breeding.

Question 22

Behavioral isolation

Answer 22

Pre-zygotic Prevents mating
Specific mating rituals

Question 23

Mechanical isolation

Answer 23

Pre-zygotic prevents fertilization
Mismatched anatomy prevents fertilization

Question 24

Gametic isolation

Answer 24

Pre-zygotic prevents fertilization
Morphology of sperm or biochemical barrier.

Question 25

Post zygotic barriers

Answer 25

Hybrid viability: low hybrid survival rate Hybrid fertility: sterile hybrids due to chromosome numbers differing Hybrid breakdown: first generation may be fertile, but 2nd is sterile

Question 26

Hybrid patterns

Answer 26

Spatially overlap zone. Patches and boundary overlap. Alleles change within zone. Hybrids have more developmental problems.

Question 27

Hybrid Environment

Answer 27

Climate change shoots hybrid zones and provide buffer to climate change.

Question 28

Results of hybrids

Answer 28

Temporary reconnection re-establishes gene flow. Real time speciation

Question 29

Hybrid reinforcement

Answer 29

Strengthening reproductive barriers. Reinforced sympatric speciation Changes occur via natural selection.

Question 30

Hybrid fusion

Answer 30

Wearing of reproductive barriers. Gene pools become more similar Biodiversity decreases

Question 31

Stability

Answer 31

Continued formation of hybrid individuals Many hybrids despite low success rate because both species often enter hybrid zones. Narrow zone= more hybrids Wider zone= less hybrids

Question 32

Time for speciation

Answer 32

4,000 years- 40 mil years Average 6.5 million years

Question 33

Speciation punctual model

Answer 33

Short speciation. Prolonged stabilization. Abrupt extinction

Question 34

Speciation gradual model

Answer 34

Small incremental changes over entire time period. Produced two species