ISCI 173 JMU Exam 4 || WITH 100% CORRECT
SOLUTIONS.
Speciation correct answers origination of one or more new species from a parental species
3 steps for speciation correct answers 1. isolation of gene pools of populations
2. changes in the gene pools of one or both of the isolated populations
3. reproductive isolation preventing gene flow
Divergence correct answers decrease in gene flow leading to independent evolution and
potential reproductive isolation
Allopatric speciation correct answers geographically separated, gene flow is reduced by
isolation and genetic drift
Sympatric speciation correct answers geographically overlapping populations, gene flow
reduced by non-random mating (selection) and mutation
Adaptive Radiation correct answers (sympatric speciation) process in which organisms
diversify rapidly into new distinct forms
Evolutions 2 predictions correct answers 1. species change through time
2. species are related by common ancestry
What is a fossil? correct answers Any trace of an organism that lived in the past
fossils are formed by sedimentation or rapid exclusion of O2
Dating Fossils correct answers relative dating
radioactive dating: technique used to date materials based on the relative presence of
radioactive elements
Transitional Forms correct answers document the intermediate states between an ancestral
form and its descendants
Vestigal Trait correct answers structure that has reduced or no function in a derived species
but was inherited from an ancestral species in which the structure was functional
Homology correct answers similarities among of different species due to common descent
(structural, genetic, and developmental)
Structural homologies correct answers morphological similarities between related species
Genetic Homologies correct answers similarities in gene or protein sequence between two
species - can use this to determine how closely related 2 species are
Developmental Homology correct answers ancestral traits maintained during early
development due to ancestral genetic cues
SOLUTIONS.
Speciation correct answers origination of one or more new species from a parental species
3 steps for speciation correct answers 1. isolation of gene pools of populations
2. changes in the gene pools of one or both of the isolated populations
3. reproductive isolation preventing gene flow
Divergence correct answers decrease in gene flow leading to independent evolution and
potential reproductive isolation
Allopatric speciation correct answers geographically separated, gene flow is reduced by
isolation and genetic drift
Sympatric speciation correct answers geographically overlapping populations, gene flow
reduced by non-random mating (selection) and mutation
Adaptive Radiation correct answers (sympatric speciation) process in which organisms
diversify rapidly into new distinct forms
Evolutions 2 predictions correct answers 1. species change through time
2. species are related by common ancestry
What is a fossil? correct answers Any trace of an organism that lived in the past
fossils are formed by sedimentation or rapid exclusion of O2
Dating Fossils correct answers relative dating
radioactive dating: technique used to date materials based on the relative presence of
radioactive elements
Transitional Forms correct answers document the intermediate states between an ancestral
form and its descendants
Vestigal Trait correct answers structure that has reduced or no function in a derived species
but was inherited from an ancestral species in which the structure was functional
Homology correct answers similarities among of different species due to common descent
(structural, genetic, and developmental)
Structural homologies correct answers morphological similarities between related species
Genetic Homologies correct answers similarities in gene or protein sequence between two
species - can use this to determine how closely related 2 species are
Developmental Homology correct answers ancestral traits maintained during early
development due to ancestral genetic cues
