Types of Evolution

Question 1

Speciation

Answer 1

• species continuously evolve which is collected form mass evidence
• speciation is When evolution leads to the evolution of an entirely new species

Question 1

Species

Answer 1

a member of species who can breed and offspring can do the same

Question 2

Modes of speciation

Answer 2

Reproductive Isolation
Allopatric Speciation
Sympatric Speciation

Question 3

Reproductive Isolation

Answer 3

any factor which prevents two populations from interbreeding while in the same region

Question 4

how to new speicies form

Answer 4

• individuals from the original species must evolve to become reproductively isolated from the remainder of the population
• This also would involve a new independent interbreeding populations

Question 5

Prezygotic

Answer 5

• what Reproductive isolating mechanism may. be classified as
• ## prevent fertilization and zygote formation

Question 6

examples of prezygotic

Answer 6

differences in breeding season, physical or behavioural traits, habitat preferences or incompatibility of gametes

Question 7

Postzygotic

Answer 7

• what Reproductive isolating mechanism may be classified as
• prevent a fertilized egg from growing into a viable adult

Question 8

examples of postzygotic

Answer 8

zygote mortality, hybrid individual inviability or hybrid infertility

Question 9

Allopatric Speciation

Answer 9

• Most new species form when a single species is separating into two geographically isolated populations
• Once populations are physically separated, they cannot exchange genetic information so are reproductively isolated
• They will respond to their environment and will become less and less similar over time.

Question 10

Sympatric Speciation

Answer 10

• A new species can also evolve from within a large population
• No geographic isolation is necessary
  -This can happen gradually, as a response to a change in the environment, or suddenly through a random mutation

Question 11

Patterns of Evolution

Answer 11

• natural selection leads to some predictable outcomes:
  -Closely related species share many homologous features, even if they do not serve the same function
• Species may have vestigial structures that once served a function in their ancestors
• Remote islands are inhabited by unique species that are descended from a few individuals who were able to reach the island

Question 12

Adaptive Radiation

Answer 12

• single species evolved into a number of distinct but closely related species
• This process most commonly occurs when a variety of new resources become available that are not being used by other species
• Darwin’s Finches

Question 13

Divergent Evolution

Answer 13

• one single species is placed under selective pressures and therefore evolves to occupy unique niches
• This has allowed us to develop such great biodiversity of life
• This is because all natural ecosystems require a number of species each with unique ecological roles
• For example, need producers, consumers, decomposers and scavengers to maintain balance with the ecosystem

Question 14

Convergent Evolution

Answer 14

• two different species evolve to occupy similar ecological niches
• Similar adaptations may be favoured in very different geographic regions that have very similar selection pressures
• For example, both sharks and dolphins have evolved streamlined bodies even though they are very distantly related

Question 15

Coevolution

Answer 15

• a species’ evolutionary success is closely linked to that of another species
• For example, certain plants have evolved hard protective shells to protects their seeds while birds also developed stronger jaws and teeth for chewing through those same hard shells
• In some extreme cases, species can become so closely dependent that the extinction of one species could lead to the extinction of the other
• Symbiotic relationships are good examples of coevolution