the rest of the evoloution booklet

Question 1

Biological species concept

Answer 1

Population were individuals are able to interbreed to produce viable offspring, populations that can reproduce will share a gene pool n become reproductively isolated from other groups

Question 2

Specieation

Answer 2

Formation of a new species,
need mechanism of evoloution and isoation for this to happen

2 modes, allopatric and sympratic

Question 3

Allopatric speciation

Answer 3

Single species seperated into 2 geographyically isolated populations, by geographic border

eg highways, bodies of water, mountain

Question 4

Sympatric speciation

Answer 4

new species created without geographical isolation, population within a single geographic location splits

Happens by non-random mating, diff selective pressures, other reproductive isolating methods

Question 5

Reproductive isolating mechanism

Answer 5

any behavioural, structural, biochemical trait that prevents individuals from reproducing successfully

Question 6

Prezygotic

Answer 6

Prevent mating or fertilization

Ecogoloical, temporal, behavioural, mechanic, gametic

Question 7

Postzygotic

Answer 7

prevent viable and fertile offspring

Zygotic, hybrid inviability, hybrid infert

Question 8

Ecological isolation

Answer 8

prezygotic mating prev

Species that live in diff habitats/seperate niches do not meet to mate

Question 9

Temporal isolation

Answer 9

Prezygotic mating
Different species mate at different times (day, season, year), so they dont mate

Question 10

Behavioural isolation

Answer 10

Prezygotic mating
the courtship and mating cues are specific, and not understood/recognized by other species

Question 11

Mechanical isolation

Answer 11

Fertilizating preven

Structural differences in reproductive organs prevent fertilization

Question 12

Gametic isolation

Answer 12

Fertilization preven

Prevents fertilization at the molecular level, eggs and sperm fail to fuse

Sperm is recognized as imposter by female immune system

Question 13

Zygotic mortality

Answer 13

Postzygotic

Fertilized zygote dies before birth, chromosomes are not compatible

eg sheeps and goats can mate but zygote is not viable

Question 14

Hybrid inviabiliity

Answer 14

The embryo develops and dies before birth or is born alive but hybrid is weak, experiences reduced survival and does not survive to reproduce

Question 15

Hybrid Infertility

Answer 15

Hybrids do develop normally and reach sexual maturity but are sterile (dont produce viable gametes) (Eg mule, horse and donkey, not a species bc not viable)

Question 16

Adaptive radiation (pattern of evoloution)

Answer 16

Rapid evoloution of a single species into many new species, driving force is filling a variety of new or formerly empty ecological niches

usually occurs when variety of new resources becomes available

eg: darwin’s finches, each island finch was diff from each other to adapt to each island

Question 17

Divergent evoloution

Answer 17

Species that were once similar to an ancestral species, diverge or become increasingly different

common ancestor, homologous structures

Question 18

Convergent evoloution

Answer 18

Similar traits arise because different species have adapted to similar environmental conditions

Diff ancestor, analogous structures

Question 19

Parallell evoloution

Answer 19

Come from common ancestor, respond to similar environmental pressures, evolve similar traits

Question 20

Coevolution

Answer 20

one species evolves in response to the evoloution of another species, symbiotic relationship

Question 21

Gradualism (speed of evoloution)

Answer 21

Evolutionary change is slow, gradual and constant

Over long periods, small changes accumulate resulting in dramatically different organisms

Evidence: fossils/transitional species

Question 22

Punctuated equillibrium

Answer 22

Evolutionary changes are rapid spurts of change, followed by long periods of little to no change

favourable mutations/sudden environmental changes cause pressures to increase

Question 23

Hardy-weinberg equilibrium principale

Answer 23

States populations allele and genotype frequency is constant unless there is some evolutionary mechanism acting upon it

for there to be change (no evoloution) it follows his 5 conditions

Question 24

Hardys 5 conditions for equilibrium?

Answer 24

Large populations
Random mating: females cant select prefered phenotypes
No mutations: no new alleles
No gene flow: no exchange of genes
No NS: no reproductive advantage