BIOL 204
BIOL 204 EXAM 3 Study Questions with
Correct Answers 2026 Updated
1
Biodiversity is recorded ____ but interpreted ___. Through what kind of observations?
recorded locally and interpreted globally. Through direct observations.
2
As habitat increases, what happens to # species observed? How is this modeled?
Species # observed increases. Modeled via species-area curves
3
Biogeography is the global ____ of ___ and ____.
global distribution of lineages and biodiversity
4
Who is the father of biology? What did he do importantly? What two patterns relating to
1) species richness and 2) biodiversity did he document in (think about space)?
Alfred Russel Wallace, traveled and collected and documented world species
Latitudinal gradient of species richness and different biodiversity in different regions
5
How many regions can be divided into biogeographic regions? What do they all differ in?
What do they correspond to?
6 regions based on plates
Differ in species richness and composition!
6
What is a clade?
A monophyletic group of organisms descended from a shared common ancestor
7
A ____ is a set of physical and environmental conditions a species requires and what else?
Niche
Conditions AND interactions with other species (predation, competition, other
relationships_
8
The geographical distribution of a given clade is determined by what five things (in brief)?
1) Ancestral niche
2) Geographic start point
3) Abiotic limitations
4) Opportunities for evolution based on location
BIOL 204
, BIOL 204
5) Time side origin
In short: history, geography, abiotic, evolution, and time
9
What is an example of an ancestral niche? What adaptations allow the niche? What limit?
Native cacti range is limited to Americas. Water conservation is shared since ancestors
evolved in an arid climate. Cold intolerance limits.
10
What history of earth determines geographical starting point?
Tectonic history!
11
When was the break up of Pangea? Separation of Gondwanaland? Of Beringia? What
species originated from Godwanaland?
180MYA
100 MYA
75 MYA
Flightless ratites (ostrich, emu, kiwi)
12
When were there land bridges between Europe and NA? When did all continents finally
separate?
65 MYA
50 MYA
13
When did the central American land bridge form? What did this cause?
3 MYA
Great american interchange! Lots of speciation due to fragmentation of marine habitats
and terrestrial habitat size increasing.
14
What was the evolutionary force and macroevolutionary outcome for snapping shrimp in
Atlantic and Pacific due to the GAI? What about the same for terrestrial mammals?
Geographic isolation caused reduced gene flow --> Allopatric speciation (speciation due to
physical separation)
Dispersal led to increased genetic drift (founder effect), leading to adaptive radiation (rapid
diversification)
15
Dispersal is ____ by individuals from where to where? What is it limited by?
movement, where they are born to where they live and breed
BIOL 204
BIOL 204 EXAM 3 Study Questions with
Correct Answers 2026 Updated
1
Biodiversity is recorded ____ but interpreted ___. Through what kind of observations?
recorded locally and interpreted globally. Through direct observations.
2
As habitat increases, what happens to # species observed? How is this modeled?
Species # observed increases. Modeled via species-area curves
3
Biogeography is the global ____ of ___ and ____.
global distribution of lineages and biodiversity
4
Who is the father of biology? What did he do importantly? What two patterns relating to
1) species richness and 2) biodiversity did he document in (think about space)?
Alfred Russel Wallace, traveled and collected and documented world species
Latitudinal gradient of species richness and different biodiversity in different regions
5
How many regions can be divided into biogeographic regions? What do they all differ in?
What do they correspond to?
6 regions based on plates
Differ in species richness and composition!
6
What is a clade?
A monophyletic group of organisms descended from a shared common ancestor
7
A ____ is a set of physical and environmental conditions a species requires and what else?
Niche
Conditions AND interactions with other species (predation, competition, other
relationships_
8
The geographical distribution of a given clade is determined by what five things (in brief)?
1) Ancestral niche
2) Geographic start point
3) Abiotic limitations
4) Opportunities for evolution based on location
BIOL 204
, BIOL 204
5) Time side origin
In short: history, geography, abiotic, evolution, and time
9
What is an example of an ancestral niche? What adaptations allow the niche? What limit?
Native cacti range is limited to Americas. Water conservation is shared since ancestors
evolved in an arid climate. Cold intolerance limits.
10
What history of earth determines geographical starting point?
Tectonic history!
11
When was the break up of Pangea? Separation of Gondwanaland? Of Beringia? What
species originated from Godwanaland?
180MYA
100 MYA
75 MYA
Flightless ratites (ostrich, emu, kiwi)
12
When were there land bridges between Europe and NA? When did all continents finally
separate?
65 MYA
50 MYA
13
When did the central American land bridge form? What did this cause?
3 MYA
Great american interchange! Lots of speciation due to fragmentation of marine habitats
and terrestrial habitat size increasing.
14
What was the evolutionary force and macroevolutionary outcome for snapping shrimp in
Atlantic and Pacific due to the GAI? What about the same for terrestrial mammals?
Geographic isolation caused reduced gene flow --> Allopatric speciation (speciation due to
physical separation)
Dispersal led to increased genetic drift (founder effect), leading to adaptive radiation (rapid
diversification)
15
Dispersal is ____ by individuals from where to where? What is it limited by?
movement, where they are born to where they live and breed
BIOL 204
