Chapter 9 - Species Diversification

Question 1

What is life?

Answer 1

the ability to replicate and the presence of some sort of metabolic activity

Question 2

What were the 3 phases that allowed for the apparition of life on earth?

Answer 2

1- the formation of small molecules containing carbon and hydrogen
2- the formation of self-replicating, information-containing molecules (RNA)
3-the development of a membrane, enabling metabolism and creating the first cell

Question 3

What was the Urey-Miller experiment?

Answer 3

They recreated the early environment of earth and see if it could lead to the apparition of life (yes - could produce all 20 amino acids that way)

Question 4

What is a specie?

Answer 4

the basic units of biodiversity

individuals can look very different within species, or look very alike but not be from the same species

Question 5

What is the biological species concept?

Answer 5

Populations of organisms that interbreed with each other are of the same species (have to be reproductively isolated from other species)

Question 6

Can artificially bred species can be considered one specie?

Answer 6

No, if the breeding is artificial there is no species creation

Question 7

What are the 2 barriers in reproduction between species?

Answer 7

1- Prezygotic (physically unable to breed with other species)
2- Postzygotic (mating produces hybrid that do not survive long after fertilzation or if they survive, they are infertile)

Question 8

What are the 2 parts of a scientific name for a species?

Answer 8

the genus (ex: homo) and the specific epithet (sapiens)

Question 9

What are ring species?

Answer 9

When 1 species split into 2 pop for whatever reason and the 2 populations evolved independently from each other to the point where they cannot breed with each other anymore (they became 2 separate species)

Question 10

What are hybrid species?

Answer 10

Interbreeding of closely related species (despite postzygotic barriers)

Question 11

What is the morphological species concept?

Answer 11

Classifies species based on their physical characteristics rather than their reproductive isolation as defining features

Question 12

What is speciation?

Answer 12

when 2 species split into 2 distinct species by the 2 (necessary) processes of reproductive isolation and genetic divergence

Question 13

What is allopatric speciation?

Answer 13

Physical separation of a specie into 2 populations and genetic divergence of the 2 resulting populations

Question 14

What is sympatric speciation?

Answer 14

speciation without geographic isolation (normal and polyploid gametes from same specie interbreed - produce sterile offspring) OR (hybrid from 2 different species reproduces asexually and makes a hybrid species of itself)

Question 15

What are systematics?

Answer 15

A way to arrange evolutionnary trees by species in a manner that indicates the ancestors they share and at which point they separated

Question 16

Are humans more advanced than cockroaches?

Answer 16

No, we might be more complex but evolutionnairly we are not more advanced

Question 17

What are monophyletic groups?

Answer 17

Closely related with each other (more than with any individual outside the group) sharing a common ancestor

Question 18

What were based evolutionary trees on before? Now?

Answer 18

Before they were based on comparative anatomy, not they are DNA based (much more precise)

Question 19

Can some characteristics be independent from common ancestors but be present in 2 different species?

Answer 19

Yes, they are called analogous traits

Question 20

What are homologous traits?

Answer 20

features inherited from a common ancestor

Question 21

What is macroevolution?

Answer 21

gives rise to bigger (+important) compounds (eyes, wings, etc), and are the result of microevolution

Question 22

What is gradual change (tempo of evolution)?

Answer 22

Evolution by creeps: the pace of evolution occurs in small steps

Question 23

What is punctuated equilibrium?

Answer 23

long periods of no change, then big steps

Question 24

What are adaptive radiations

Answer 24

times of extreme diversification; when a small number of species diversifies into a much larger number of species

Question 25

What are the 3 phenomena that can trigger adaptive radiations?

Answer 25

• Mass extinction events (remaining species rapidly diversify)
• Colonization events (moving to a new location with new resources (and possibly less predators); colonizers can rapidly diversify
• Evolutionary innovations (the evolution of an innovative feature that increases fitness can allow a specie to rapidly diversify)

Question 26

What are the 3 domains of organisms?

Answer 26

Eukarya, Bacteria, Archaea

Question 27

What are theb 5 kingdoms of eukarya?

Answer 27

monera, plant, animal, fungi, protists