Topic 5.4 - Cladistics

Question 1

Clade

Answer 1

Group of organisms that have evolved from a common ancestor

Question 2

Identifying members of a clad

Answer 2

Species in a similar clade will have similar base sequences for genes and similar amino acid base sequences of a protein.

Question 3

Molecular clocks

Answer 3

The DNA base sequence differences between two species have a positive correlation between the time since diverging and the number of differences.

Question 4

Convergent evolution

Answer 4

Evolution that occurs due to adaptation to the environment. Convergent evolution can cause species to have analogous features as their features may have the same purpose but have different evolution pathways (Octopus eye and human eye)

Question 5

Homologous features

Answer 5

Same evolution pathway, different function and different outward appearance - usually occurs due to having similar ancestry (whale flippers and human arms )

Question 6

Cladograms

Answer 6

Show the most probable sequence of divergence in clades

Question 7

Primates

Answer 7

Species most similar to humans - bonobo and chimpanzee

Question 8

Cladistics and reclassification

Answer 8

Cladistics produced at the end of the 20th century showed that classification based on structure was incorrect since some of those classed together did not have the same ancestral origins

Question 9

Extant

Answer 9

Opposite of extinct - living