BSC2011 Exam 1 Study Guide - UWF - Dr. Clifton
Homologous Structures definition and example (CH 26 STARTS HERE) - -Homology is
similarity due to shared ancestry. An example is the similarity in the number and
arrangement in the bones in the forelimbs of mammals bc they descend from a common
ancestor... this is an example of morphological homology.
-Analagous Structures definition and example - -Analogy is ancestry due to convergent
evolution. Example would be animals that have wings or fins that perform similar functions
but do not share a common ancestor
-Goals of systematics - -Systematics is a discipline focused on classifying organisms and
determining their evolutionary relationships
-Cladistics - -Approach to systematics where common ancestry is the primary criterion
used to classify organisms
-taxonomy - -Scientific discipline focused on how organisms are named and classified
-two classification systems we discusssed - -1) Binomial Nomenclature - first part is the
genus and second part is the specific epithet, which is unique for each species within the
genus. Examples include Panthera pardus AKA leopard and Homo sapien AKA human or
"wise man"
2)Hierarchical Classification - a hierarchy of increasingly inclusive categories; the Linean
naming system
-Categories of classification used in systematics (general -> most specific) - -Domain;
Kingdom; Phylum; Class; Order; Family; Genus; Species (DKPCOFGS)
-Clade - -A clade is a group of species that includes an ancestral species and all its
descendants.
-Taxon - -The named taxonomic unit at any level of the hierarchy
-Sister group - -Groups of organisms that share an immediate common ancestor
-Monophyletic - -A taxon that consists of an ancestral species and all of its descendants (a
taxon is equal to a clade if...)
-Paraphyletic - -A taxon that consists of an ancestral species and some, but not all of its
descendants
-Polyphletic - -A taxon that consists of distantly related species but does not include their
most recent common ancestor
, -Apomorphy - -A derived character
-synapomorphy (shared derived character) - -An evolutionary novelty unique to a
particular clade (Ex: hair is shared by all mammals but NOT found in their ancestors)
-symplesiomorphy (shared ancestral character) - -A character that originated in an
ancestor of the taxon (Ex: backbone in mammals bc all mammals have a backbone but a
backbone does not distinguish mammals from other vertebrates)
-automorphy - -
-ingroup - -Linage that includes the species being studied
-outgroup - -A species or group of species from an evolutionary lineage that is known to
have diverged before the lineage that includes the species being studied
....look at chart pg 554 the Lancelot is a good out-group bc it is a member of the chordates
group but it it is unlike the vertebrates bc it does not have a backbone...
-phylogenetic tree - -A branching diagram representing the evolutionary history of a
group of organisms
-cladograms - -
-parismony - -AKA Occam's razor - the simplest explanation is often the best. Ex: In the
case of tree based on morphology, the most parsimonious tree requires the fewest
evolutionary events, as measured by the origin of shared derived morphological
characteristics (for phylogenies based on DNA, the most parsimonious tree requires the
fewest base changes)
-maximum liklihood - -The tree most likely to have produced a given set of DNA data,
based on certain probability rules about how DNA sequences change over time Ex:
Probability rules could be based on the assumption that all nucleotide substances are
equally likely; however, if evidence suggests that the assumption is not correct, more
complex rules could be devised to account for the different rates of change among different
nucleotide or at different positions in a gene
-interperet relationships among organisms in simple phylogenetic tree - -i'll try my best
-how molecular biology is used as a tool in systematics - -
-how molecular clocks are used to track time - -A molecular clock uses constant rates of
evolution in some genes to estimate the absolute time of every evolutionary change
-why some studies use DNA coding for ribosomal RNA (rRNA) and other studies used
mitochondrial DNA (mtDNA) - -Some ribosomal rRNA changes relatively slowly and is best
used for investigating relationships for taxa that diverged hundreds of millions of years
Homologous Structures definition and example (CH 26 STARTS HERE) - -Homology is
similarity due to shared ancestry. An example is the similarity in the number and
arrangement in the bones in the forelimbs of mammals bc they descend from a common
ancestor... this is an example of morphological homology.
-Analagous Structures definition and example - -Analogy is ancestry due to convergent
evolution. Example would be animals that have wings or fins that perform similar functions
but do not share a common ancestor
-Goals of systematics - -Systematics is a discipline focused on classifying organisms and
determining their evolutionary relationships
-Cladistics - -Approach to systematics where common ancestry is the primary criterion
used to classify organisms
-taxonomy - -Scientific discipline focused on how organisms are named and classified
-two classification systems we discusssed - -1) Binomial Nomenclature - first part is the
genus and second part is the specific epithet, which is unique for each species within the
genus. Examples include Panthera pardus AKA leopard and Homo sapien AKA human or
"wise man"
2)Hierarchical Classification - a hierarchy of increasingly inclusive categories; the Linean
naming system
-Categories of classification used in systematics (general -> most specific) - -Domain;
Kingdom; Phylum; Class; Order; Family; Genus; Species (DKPCOFGS)
-Clade - -A clade is a group of species that includes an ancestral species and all its
descendants.
-Taxon - -The named taxonomic unit at any level of the hierarchy
-Sister group - -Groups of organisms that share an immediate common ancestor
-Monophyletic - -A taxon that consists of an ancestral species and all of its descendants (a
taxon is equal to a clade if...)
-Paraphyletic - -A taxon that consists of an ancestral species and some, but not all of its
descendants
-Polyphletic - -A taxon that consists of distantly related species but does not include their
most recent common ancestor
, -Apomorphy - -A derived character
-synapomorphy (shared derived character) - -An evolutionary novelty unique to a
particular clade (Ex: hair is shared by all mammals but NOT found in their ancestors)
-symplesiomorphy (shared ancestral character) - -A character that originated in an
ancestor of the taxon (Ex: backbone in mammals bc all mammals have a backbone but a
backbone does not distinguish mammals from other vertebrates)
-automorphy - -
-ingroup - -Linage that includes the species being studied
-outgroup - -A species or group of species from an evolutionary lineage that is known to
have diverged before the lineage that includes the species being studied
....look at chart pg 554 the Lancelot is a good out-group bc it is a member of the chordates
group but it it is unlike the vertebrates bc it does not have a backbone...
-phylogenetic tree - -A branching diagram representing the evolutionary history of a
group of organisms
-cladograms - -
-parismony - -AKA Occam's razor - the simplest explanation is often the best. Ex: In the
case of tree based on morphology, the most parsimonious tree requires the fewest
evolutionary events, as measured by the origin of shared derived morphological
characteristics (for phylogenies based on DNA, the most parsimonious tree requires the
fewest base changes)
-maximum liklihood - -The tree most likely to have produced a given set of DNA data,
based on certain probability rules about how DNA sequences change over time Ex:
Probability rules could be based on the assumption that all nucleotide substances are
equally likely; however, if evidence suggests that the assumption is not correct, more
complex rules could be devised to account for the different rates of change among different
nucleotide or at different positions in a gene
-interperet relationships among organisms in simple phylogenetic tree - -i'll try my best
-how molecular biology is used as a tool in systematics - -
-how molecular clocks are used to track time - -A molecular clock uses constant rates of
evolution in some genes to estimate the absolute time of every evolutionary change
-why some studies use DNA coding for ribosomal RNA (rRNA) and other studies used
mitochondrial DNA (mtDNA) - -Some ribosomal rRNA changes relatively slowly and is best
used for investigating relationships for taxa that diverged hundreds of millions of years
