Define the theory of evolution. [Knowledge]
The general term for evolution is any process of change. Biological evolution is
descent with modification. Characteristics of a population change over time.
Individuals with certain heritable traits produce more offspring than those without
Describe how evolution explains (or is responsible for) the unity and diversity of life on
Evolution is responsible for the unity and diversity of life and implies that all
organisms come from a common ancestor. Life on Earth has changed over time.
Different species share common ancestors.
Explain how evolution ‘works’ making reference to populations, individuals, and
Evolution is caused by random genetic mutations and natural selection.
Individuals don’t evolve rather populations do. If a mutation affects a population,
then the offsprings will inherit those derived traits. Similarly, spp with an
advantage in a particular environment are more likely to reproduce and thereby
changing the population through natural selection.
Describe characteristics of model organisms ideal for evolutionary studies (be sure that
you can explain why these are ideal characteristics). [Knowledge, Comprehension]
Model organisms that are ideal for evolutionary study are organisms with short
life span, they breed quickly (we can see if the inherited trait is passed on), they
mature quickly (reach reproduction stage very quickly after their born and
therefore they can produce offsprings quickly), small (easy to have in a lab), easy
to maintain (managing all the model organisms will not be difficult) and with fairly
easy ethics approval.
Define key terms (phylogenetics): systematics, morphology, phylogeny, taxonomy,
classification,taxonomic hierarchy, taxon, lineage, monophyletic taxa, common ancestor,
paraphyletic taxa, polyphyletic taxa, principle/assumption of parsimony, mosaic
evolution, ancestral characters, and derived characters (section 19.5). [Knowledge]
Phylogenetics: the study of evolutionary relatedness among groups of org.
looking at genetic sequences and morphology
Systematics: the branch of biology that studies the diversity of life and its
Morphology: the study of the form and structure of organisms and their specific
Phylogeny: the evolutionary history of a group of organisms.
Taxonomy: the science of the classification of organisms into an ordered system
that indicates natural relationship.
Classification: an arrangement of organisms into hierarchical groups that reflect
their relatedness Taxonomic hierarchy: a system of classification based on arranging organisms
into ever more inclusive categories.
Taxon (taxa): a sname designating a group of organisms included within a
category in the Linnaean taxonomic hierarchy.
Lineage: group composed of species, taxa, or individuals related by descent
from a common ancestor
Monophyletic taxa: a group of organisms that includes a single ancestral species
and all of its descendants.
Polyphyletic: a group of organisms that belong to different evolutionary lineages
and do not share a recent common ancestor
Paraphyletic: a group of organism that include an ancestral species and some, but
not all of its descendents.
Common ancestor: an ancestral organism shared by 2 or more descendant
Principle of parsimony: a principle of systematic biology that states that a
particular trait is unlikely to evolve independently in separate evolutionary
Assumption of parsimony: assumption that the simplest explanation should be
the most accurate.
Mosaic evolution: the tendency of characteristics to undergo different rates of
evolutionary change within the same lineage
Ancestral characters: a trait that was present in a distant common ancestor
Derived characters: a new version of a trait found in the most recent common
ancestor of a group
Using the Linnaean system of classification, list from most inclusive, to least inclusive,
the terms: phyla, family, genus, species, and domain. [Knowledge, Comprehension]
Domain, phyla, family, genus, species
Relate the above terms, and their degree of inclusion, to the relative number of
organisms (individuals and types of organisms) found within each, explaining how, with
respect to the relative numbers of individuals at each level, a mailing address is
analogous to the Linnaean taxonomic system. [Comprehension, Analysis, Application]
Domain includes all species (a large number) and therefore it is the most
inclusive. As you go down the list, you become more specific and there are fewer
species being represented. Thus, it becomes less inclusive as you go down the
linnean system of classification. A mailing address is similar in that you start with
you specific and you become more broader.
Describe what is represented by a phylogenetic tree. [Comprehension]
A phylogenetic tree represents the evolutionary relationships of groups of
Read a phylogenetic tree. [I.e., given a phylogenetic tree, determine: where speciation
events occurred (nodes), common ancestors between specific lineages, orientation of
time scale, unique vs. shared histories, and provide one limitation of interpreting a
phylogenetic tree.] [Comprehension, Analysis, Application] Section 19.5
Explain why systematists would look at characters that are genetically independent.
It’s necessary because different organismal characters have the same genetic
Define and differentiate between the following terms with respect to the information they
provide regarding shared ancestry and their use in constructing phylogenies: homology
(homologous), analogy (analogous), and homoplasy (homoplasious) [Knowledge,
Homology: traint that came from a common ancestor
Analogy: traits with the same function in distantly related species
Homoplasy: similarity in species due to convergent evolution; cladistic term for
Given the relationship between several groups of organisms, identify structures (e.g.,
forelimbs and wings of tetrapods) as homologous or homoplasious (analogous).
Wings of tetrapods is analogous to wings of birds (therefore analogous). Not too
sure what this question is asking
Differentiate between ancestral and derived characters and their use in determining
evolutionary relationships. [Knowledge, Analysis]
Ancestral characters are old forms of traits while derived characters are new
forms of traits. Derived characters provide useful information about evolutionary
relationships because once a derived character becomes established; it’s usually
present in all of that species’ descendants.
Describe how outgroup analysis (or comparison) is used to identify ancestral or derived
Outgroup analysis involves comparing the group under study with more distantly
related species not otherwise included in analysis. This can help determine if a
character is derived or ancestral (so if the outgroup comparison contains the
character, than it means it’s ancestral however if it doesn’t, then it’s derived).
Identify a phylogenetic tree or description of a group of organisms as monophyletic,
paraphyletic or polyphyletic. [Analysis, Application] (19.6)
Define cladistics and briefly describe how it produces phylogenetic hypotheses.
[Knowledge, Comprehension] (19.6b) Cladistics produced phylogentic hypothesis and classifications that reflect only
the branching patterns of evolution. Cladists group together species that share
Describe how the principle/assumption of parsimony is used to construct phylogenetic
trees.[Comprehension] (look at 19.6b, as well)
Phylogenetic trees take on the most simplest explanation by looking at
homologous traits. Analagous traits are more rare and therefore not considered in
creating phylogenetic trees.
Describe briefly how a traditional evolutionary systematist determines evolutionary
relationships compared to a cladis. [Comprehension]
Systematists want to classifications to mirror phylogenetic history (evolutionary
history) while a cladist will make groupings based on shared dertived characters
(they ignore morphological divergence).
Define key terms (history of evolutionary thought): biogeography, comparative, vestigial
traits, Scala Naturae/ladder of life, catastrophism, uniformitarianism, gradualism,
inheritance of acquired characteristics. [Knowledge]
Biogeography: study of geographic distributions of plants and animals
Comparative morphology: analysis of the structure of living and extinct
Ladder of life: species had a purpose in the Great chain of being
Catastrophism: sudden changes in the world occurred and resulted in mass
extinction. (Cuvier went on to saying that God repopulated the Earth)
Gradualism: slow processes over long geologic time periods
Uniform: present is key to past and vice versa (relatively same rate in terms of
Inheritance of acquired characteristics: changes that an organism acquires in its
lifetime are inherited by its offspring.
Explain why Lamarck’s hypotheses/principles of use and disuse, and inheritance of
acquired characteristics leading to evolutionary change, are not supported.
His hypotheses are not supported because evolution is not based on how often a
structure is used or not used but rather the genetics. In other words, an
organism’s behaviour has no effect on its inheritable traits.
List Lamarck’s four major contributions to evolutionary thought and explain why three of
these were integral to Darwin’s evolution by natural selection. [Knowledge]
1) He proposed that all species change thru time
2) He recognized that changes are passed from generation to the next
3) He suggested that organisms change in response to their environments 4) He hypothesized the existence of specific mechanisms that caused
The first 3 were important in Darwin’s evolution by natural selection because traits
that are more advantageous to a particular environment will more likely be passed
on to subsequent generations. If that’s the case, populations will change thru time
as they adapt to their environments.
Explain why gradualism and uniformitarianism were integral to Darwin’s evolution by
natural selection. [Comprehension] o (Another way of looking at