Week 6: Lecture 2: Systematics, Phylogeny And Tree Of Life

Question 1

Three schools of thought in systematics

Answer 1

1. Phenetic system
2. Classic evolutionary system
3. Cladistic system

Question 2

Phylogenetic trees

Answer 2

A graphical representation of evolutionary relationships among a set of organisms or groups of organisms (horizontal or vertical)

Question 3

Types of phylogenetic trees

3

Answer 3

Monophyletic
Paraphyletic
Polyphyletic

Question 4

Parsimony

Answer 4

(A phylogenetic tree is only a hypothesis of the evolutionary relationships between organisms in the tree)
So draw multiple trees
And select the tree with the least steps which is most simple

Question 5

Why can morphological and genetic similarity between two species be different
2 reasons

Answer 5

• body form changes at a different rate to RNA/DNA

- much molecular evolution not expressed in body form

Question 6

Methods to add time to a phylogenetic tree

3

Answer 6

Radio metric data
Stratigraphy
Molecular clocks

Question 7

Radiometric data

Answer 7

Compares amount of radioactive isotope with amount of decay products (decay rate known) to estimate age.
(Carbon 12 can be used)

Question 8

Stratigraphy

Answer 8

Layering of deposited rocks allows geological timescale to be estimated.

Question 9

Molecular clocks

Answer 9

Amount of genetic divergence used to estimate timing.

Question 10

Six kingdoms in the tree of life

Answer 10

Animalia
Plantae
Fungi
Archaea
Protista
Eubacteria

Question 11

Animalia is more closely related to which other kingdom than plantae?

Answer 11

Fungi

Question 12

Heterotrophic

Answer 12

An organism that eats other plants or animals for energy and nutrients.