Speciation

Question 1

Types of Evidence of Evolution

Answer 1

• Fossils
• Anatomy & molecular biology
• Embryology
• Biogeography

Question 2

Fossils (Evidence of Evolution)

• Show org not seen anymore
• Show g change

Answer 2

• Can present organisms not seen today
• Can show gradual change over time

ex 1 : Horses show progression of teeth
and toes to modern configuration
ex 2 : Whales also shows progression
from 4-limbed, terrestrial, cat-sized
animals to large, aquatic behemoths

Question 3

Anatomy & Molecular Biology (Evidence of Evolution)

• Sim in struct &/or g –> common A
• VS –> present in MA & without f today

Answer 3

• Similarity in structures and/or genes results from common
  ancestry
• Vestigial structures: structures from a past ancestor that are present in modern animals but don’t have an apparent function today

Question 4

Embryology (Evidence of Evolution)

• Sim in structures seen at ES –> common A

Answer 4

Similarity in structures seen at embryonic stages results from
common ancestry (though may not be seen in adult stages)

Question 5

Biogeography (Evidence of Evolution)

• Dist of o tracks w/ tec mvmnt

Answer 5

Distribution of organisms tracks with tectonic movement in past

Ex : The distribution of ratite animals, such as ostriches, emus & kiwis, in the southern hemisphere indicates the group has evolved since the Jurassic (Gondwana) period

Question 6

Modes of Speciation

• AS –> diverge
  
  • D –> p of pop
  • V –> b created to s pop
• SS –> evolve

Answer 6

Allopatry Speciation :When a population is split, two groups can begin to diverge into new species
- Dispersal = portion of population
moves
- Vicariance = natural barrier created to
split population

Sympatry Speciation : New species can evolve within and amongst existing populations