ENVT 101 VERIFIED STUDY GUIDE
Chapter 4
Evolution• - Answers - A trait must be inherited (genetic) for it to evolve
Individuals with traits that make them suited to a particular environment - Answers -
survive and reproduce at a greater rate in that environment than individuals with less
suitable traits
Charles Darwin: Naturalist and Geologist (1809-1882) - Answers -
Adaptation - Answers - • The acquisition of traits that allow a species to survive in its
environment
• Explained by Charles Darwin's theory of evolution by natural selection
Natural Selection - Answers - • The process of better-selected individuals passing their
traits to the next generation
Where do the differences in the genes within individuals come from? - Answers -
Mutations
• Mutations - Answers - • Changes in DNA coding sequence that occur by chance•
Random mistakes in DNA replications• Exposure to radiation• Toxins
Limiting Factor on where organism can live - Answers - Limiting Factor: Govern by the
environmental factors
• Physiological stress
• Competition with other species
• Predation, parasitism, diseases
• Climate and weather change
• Human disturbance
• Pollution•
Habitat destruction
Critical Limits - Answers - • The factor in shortest supply relative to demand is the
critical factor in a species distribution (Justus von Liebig: 1840
Tolerance limits - Answers - • Each environmental factor has both minimum and
maximum levels
Critical Limits - Answers - • Interaction of several factors determines biogeographical;
distribution• Tolerance limits may affect the distribution of young different than adults
,Indicators - Answers - • Indicates the presence of particular conditions• Presence or
absence of indicator species indicates ecosystem conditions
Habitat - Answers - • Set of environmental conditions in which a particular organism live
Ecological niche (Charles Elton: 1900-1991) - Answers - • Role played by a species in a
biological community
• Total set of environmental factors that determine a species distribution
Generalists - Answers - • Has a broader niche
• Can tolerate a wide range of habitat conditions
Specialists - Answers - • Occupy a narrow ecological niche
• Live in very limited condition
s• Often endemic species
Principle of competitive exclusion - Answers - • Complete competitors cannot coexist
(G.F. Gause: 1910-1986)
• The one that is more efficient in using resources will exclude the other
Resource partitioning - Answers - • Species with same niches divide up a resource
Speciation - Answers - • Development of new species• Can occur due to• Geographic
isolation
Allopatric Speciation - Answers - • The new population evolves independently of the
first, creating a new species
Directional selection - Answers - • The shift towards one extreme of a trait
Stabilizing selection - Answers - • Range of a trait is narrowed
Disruptive selection - Answers - • Traits diverge toward the two extremes
Taxonomy - Answers - • Study of organisms and their relationships
• Species are assigned with a Latin name with two parts(a binomial)E.g., Pinus
resinosa: Red Pine
Organisms are the categorized into broader taxonomic categories - Answers - •
Kingdoms
• Phyla
• Families
, • Genera
Coevolution• - Answers - Two (or more) species influence each other's evolutionary
process Can be
• Antagonistic OR• Mutually beneficial
intraspecific competition - Answers - competition between members of the same
species
interspecific competition - Answers - competition between members of different species
Predator - Answers - • Any organism that feeds directly on anotherorganism
Predator-mediated competition - Answers - • Predators may reduce the abundance of a
weaker competitor
AS predators become more efficient, - Answers - • The prey evolve defenses (thorns,
toxic chemicals, etc.
Coevolution - Answers - Overtime predator and prey evolve:
Batesian mimicry (parasitic benefit) - Answers - A type of mimicry in which a harmless
species looks like a species that is poisonous or otherwise harmful to predators.
Müllerian mimicry :(Mutual benefit) - Answers - two or more unpalatable species
resemble each other
Symbiosis - Answers - • Two or more species live intimately together withtheir fates
linked• Symbiosis Includes
Mutualism - Answers - • Both organisms benefit from their association
Commensalism - Answers - • One species benefits while the other neitherbenefits nor
harmed
Parasitism - Answers - • A form of predation, is also sometimes consideredas symbiosis
Keystone Species - Answers - • Plays a critical role in a biological community that is out
of proportion to its abundance
Ecosystem Engineers - Answers - • Affect the availability of resources• They can
modify, maintain, and /or create habitats
Abundance - Answers - • Total number of organisms in a community
Chapter 4
Evolution• - Answers - A trait must be inherited (genetic) for it to evolve
Individuals with traits that make them suited to a particular environment - Answers -
survive and reproduce at a greater rate in that environment than individuals with less
suitable traits
Charles Darwin: Naturalist and Geologist (1809-1882) - Answers -
Adaptation - Answers - • The acquisition of traits that allow a species to survive in its
environment
• Explained by Charles Darwin's theory of evolution by natural selection
Natural Selection - Answers - • The process of better-selected individuals passing their
traits to the next generation
Where do the differences in the genes within individuals come from? - Answers -
Mutations
• Mutations - Answers - • Changes in DNA coding sequence that occur by chance•
Random mistakes in DNA replications• Exposure to radiation• Toxins
Limiting Factor on where organism can live - Answers - Limiting Factor: Govern by the
environmental factors
• Physiological stress
• Competition with other species
• Predation, parasitism, diseases
• Climate and weather change
• Human disturbance
• Pollution•
Habitat destruction
Critical Limits - Answers - • The factor in shortest supply relative to demand is the
critical factor in a species distribution (Justus von Liebig: 1840
Tolerance limits - Answers - • Each environmental factor has both minimum and
maximum levels
Critical Limits - Answers - • Interaction of several factors determines biogeographical;
distribution• Tolerance limits may affect the distribution of young different than adults
,Indicators - Answers - • Indicates the presence of particular conditions• Presence or
absence of indicator species indicates ecosystem conditions
Habitat - Answers - • Set of environmental conditions in which a particular organism live
Ecological niche (Charles Elton: 1900-1991) - Answers - • Role played by a species in a
biological community
• Total set of environmental factors that determine a species distribution
Generalists - Answers - • Has a broader niche
• Can tolerate a wide range of habitat conditions
Specialists - Answers - • Occupy a narrow ecological niche
• Live in very limited condition
s• Often endemic species
Principle of competitive exclusion - Answers - • Complete competitors cannot coexist
(G.F. Gause: 1910-1986)
• The one that is more efficient in using resources will exclude the other
Resource partitioning - Answers - • Species with same niches divide up a resource
Speciation - Answers - • Development of new species• Can occur due to• Geographic
isolation
Allopatric Speciation - Answers - • The new population evolves independently of the
first, creating a new species
Directional selection - Answers - • The shift towards one extreme of a trait
Stabilizing selection - Answers - • Range of a trait is narrowed
Disruptive selection - Answers - • Traits diverge toward the two extremes
Taxonomy - Answers - • Study of organisms and their relationships
• Species are assigned with a Latin name with two parts(a binomial)E.g., Pinus
resinosa: Red Pine
Organisms are the categorized into broader taxonomic categories - Answers - •
Kingdoms
• Phyla
• Families
, • Genera
Coevolution• - Answers - Two (or more) species influence each other's evolutionary
process Can be
• Antagonistic OR• Mutually beneficial
intraspecific competition - Answers - competition between members of the same
species
interspecific competition - Answers - competition between members of different species
Predator - Answers - • Any organism that feeds directly on anotherorganism
Predator-mediated competition - Answers - • Predators may reduce the abundance of a
weaker competitor
AS predators become more efficient, - Answers - • The prey evolve defenses (thorns,
toxic chemicals, etc.
Coevolution - Answers - Overtime predator and prey evolve:
Batesian mimicry (parasitic benefit) - Answers - A type of mimicry in which a harmless
species looks like a species that is poisonous or otherwise harmful to predators.
Müllerian mimicry :(Mutual benefit) - Answers - two or more unpalatable species
resemble each other
Symbiosis - Answers - • Two or more species live intimately together withtheir fates
linked• Symbiosis Includes
Mutualism - Answers - • Both organisms benefit from their association
Commensalism - Answers - • One species benefits while the other neitherbenefits nor
harmed
Parasitism - Answers - • A form of predation, is also sometimes consideredas symbiosis
Keystone Species - Answers - • Plays a critical role in a biological community that is out
of proportion to its abundance
Ecosystem Engineers - Answers - • Affect the availability of resources• They can
modify, maintain, and /or create habitats
Abundance - Answers - • Total number of organisms in a community
