Speciation + Phylogenetics

Question 1

What is life?

Answer 1

• reproduction
• metabolism
• ability to respond/adapt
• growth
• homeostasis

Question 2

When did life evolve?

Answer 2

about 4.5 billion yrs ago

Question 3

Where did life first evolve?

Answer 3

• shallow seas
• deep sea thermal vents
• extraterrestrial origins

Question 4

Spontaneous generation

Answer 4

1. little atmospheric O
2. lots of E
3. no competition

Question 5

LUCA

Answer 5

Last Universal Common Ancestor

Question 6

3 domains

Answer 6

1. bacteria
2. eukarya
3. archaea

Question 7

Miller-Urey hypothesis - origin of life

Answer 7

1. abiotic synthesis of small org molecs/monomers
2. joining of these small molecs into polymers
3. membrane-bound protocells
4. origin of self-replicating molec

Question 8

prokaryotes flourished

Answer 8

3.7 mill yrs ago

Question 9

biological species concept

Answer 9

• mate & prod fertile offspring, then they are the same species
• actually or potentially interbreeding pops that are reproductively isolated from all other such groups

Question 10

morphospecies concept

Answer 10

members of the same species usually look alike

Question 11

ecological species concept

Answer 11

a group of organisms adapted to a particular niche

Question 12

niche

Answer 12

conditions and resources that define the requirements of a species

Question 13

the species problem(s)

Answer 13

• hybrids
• fossils (only morphospecies)
• asexuals
• bacteria (horizontal gene transfer)

Question 14

pre-zygotic barriers

Answer 14

• behavioral
• physical
• time
• space

Question 15

post-zygotic barriers

Answer 15

genetic incompatibility

Question 16

speciation

Answer 16

the evolutionary process by which new biological species arise

Question 17

general model of speciation

Answer 17

1. genetic drift
2. natural selection
3. mutation

Question 18

allopatric speciation

Answer 18

speciation that depends on an external barrier to gene flow (geographic isolation) to begin/complete the event

Question 19

sympatric speciation

Answer 19

speciation in which new species evolve from a single ancestral species while inhabiting the same geographic region (common in plants)

Question 20

adaptive radiation

Answer 20

rapid diversification in which natural selection accelerates the rates of speciation

Question 21

co-speciation

Answer 21

when 2 groups of org’s speciate in response to each other at the same time (eg. parasite/host)

Question 22

instantaneous speciation

Answer 22

2 species hybridize and prod offspring that are reproductively isolated from both parents (plants, not animals)

Question 23

Linnaeus

Answer 23

• father of taxonomy

- plants & animals

Question 24

Whittaker

Answer 24

• 5 kingdom system
  1. monera
  2. protista
  3. plantae
  4. fungi
  5. animalia
• problems:
  1. 2 distinct lineages of prokaryotes
  2. protista not monophyletic

Question 25

gene flow

Answer 25

- movement of genes btwn pops | - inhibits speciation events

Question 26

phylogenetic tree

Answer 26

a branching diagram that represents a hypothesis about the evolutionary history of a group of orgs

Question 27

Louis Pasteur

Answer 27

disproves modern day spontaneous generation (regeneration)

Question 28

what evolves faster, the non-coding or coding sections of genes?

Answer 28

non-coding -> more mutations

Question 29

cladistics

Answer 29

classifying organisms into clades based on common descent

Question 30

monophyletic

Answer 30

the ancestor and all of its descendants

Question 31

character is similar because (2)

Answer 31

1. convergent evolution | 2. common descent

Question 32

shared common ancestor

Answer 32

character that originated in an ancestor (eg. backbone)

Question 33

shared derived character

Answer 33

evolutionary novelty unique to a particular clade (eg. hair)

Question 34

parsimony

Answer 34

simplest form; reqs the smallest amount of changes

Question 35

Permian extinction

Answer 35

- 250 mya - claimed about 96% of marine species - plants not impacted much

Question 36

Cretaceous extinction

Answer 36

- 65 mya | - dinosaurs

Question 37

extinctions

Answer 37

opportunity for adaptive radiations