Evolution

Question 1

Lamarck’s Theory of Acquired Traits

also know the difference between his and Darwin’s theory

Answer 1

• evolution by acquired traits
• creatures developed traits during their lifetime and then passed them down to their offspring
• example: giraffes stretched their necks to reach leaves in tall trees and then passed on this trait

*this is not correct

Question 2

Darwin’s Theory of Natural Selection

Answer 2

(1) more individuals are produced than can survive;
(2) there is therefore a struggle for existence;
(3) individuals within a species show variation; and
(4) offspring tend to inherit their parents’ characters.

example: giraffes who already have longer necks survived the best, and the others died, so this became the only trait to inherit.

Question 3

“fit” or reproductive potential

Answer 3

individuals that leave behind the most viable, fertile offspring are more fit than individuals who merely reach old age without the same degree of reproduction.

Question 4

Darwin’s Finches

Answer 4

they are known for their remarkably diverse beak for and function, that was evolved to suit different foods. these birds helped Darwin justify his theory of evolution.

Question 5

Fossil Record

evidence supporting Darwin’s theory

Answer 5

• history of life documented by fossils and the collection of them.
  a) Law of Superposition - age is based on the layer of rock
  b) Radiometric Dating - a method of dating rocks and minerals using radioactive isotopes

Question 6

Comparative Anatomy

evidence supporting Darwin’s theory

Answer 6

• comparing the structure
  a) Homolgous Structures - similar bone arrangement but different functions due to DIVERGENT evolution. reveals shared common ancestor with shared similar genes.
  b) Analogous Structures - similar functions due to shared environment but are not similar in actual structural make up. Results from CONVERGENT evolution. Organisms do NOT share a recent common ancestor or shared genes

ex: humans and cats for a)
ex: bird and butterfly wings for b)

Question 7

Vestigal Structures

evidence that supports Darwin’s theory

Answer 7

• structures that are retained in the body but do not have any apparent funtion.

birds with wings that dont use them

Question 8

Comparative Embryology

evidence that supports Darwin’s theory

Answer 8

• all vertebrate embryos have a tail and pharyngeal gill slits which are lost in the adult form of some vertebrates.

humans have tails when they are embryos

Question 9

Molecular Record

evidence supporting Darwin’s theory

Answer 9

• the most strongest and conclusive piece of evidence
  DNA nucleotide sequence comparisons
  RNA nucleotide sequence comparisons
  Amino acid sequence comparisons

shows the similariy and differences of our DNA with different species.

Question 10

Artificial Selection

evidence supporting Dawrin’s theory

Answer 10

• humans control which traits are selected.

dog breeding