Bio 1200; Chapter 23 Systematics, Phylogenies, and Comparative Biology

According to this phylogeny, which of the following groups form clades? A) Hawk and Velociraptor B) Turtles and Crocodiles C) Giraffe and Bat D) Stegosaurus and Tyrannosaurus E) Stegosaurus, Tyrannosaurus, and Velociraptor

A) Hawk and Velociraptor C) Giraffe and Bat

How are homologous and homoplastic traits different ? A) Homologous traits are inherited from a common ancestor; homoplastic traits are not B) Homoplastic traits are common to all life on Earth; homologous traits are not C) Homologous traits are common to all life on Earth; homoplastic traits are not D) There is no difference; they are synonyms E) Homoplastic traits are inherited from a common ancestor; homologous traits are not

A) Homologous traits are inherited from a common ancestor; homoplastic traits are not

When more than one process could have caused a pattern in biological diversity that is observed today, what methods do scientists use to distinguish between those competing hypotheses? A) Phylogenetic Methods B) Maximum likelihood methods C) Molecular Methods D) Experimental Methods

A) Phylogenetic Methods

Which of the following statements are true regarding the use of the molecular clock? A) The evolutionary changes in genes with a constant rate of change can be determined B) Data indicate that rates of evolution are similar for most genes, so timing estimates are usually applicable to other genes in the same organism C) To date, no alternative methods have been developed D) It may be used to determine the timing of clade branching events for a particular molecule

A) The evolutionary changes in genes with a constant rate of change can be determined D) It may be used to determine the timing of clade branching events for a particular molecule

Which of the following are true of scientific, or species names? A) The first word is always capitalized B) They are written in italics C) They are always the same, regardless of language spoken D) The first word is the family to which the organism belongs. E) They can be the same for more than one species as long as they are classified in different kingdoms.

A) The first word is always capitalized B) They are written in italics C) They are always the same, regardless of language spoken

____________ structures are those that are derived from the same boy part in a common ancestor.

Homologous

In cladistics, a(n) ____________ is any aspect of the phenotype, including morphology, physiology, behavior, and DNA.

character

Evolutionary relationships among species are evaluated through the identification of shared derived characters in an approach called _______.

cladistics

A ____________ is constructed by nesting clades characterized by shared derived characters.

cladogram

In cladistics, a character state is __________ by determining whether it is ancestral or derived.

polarized

The number of species within a clade is also known as its species __________.

richness

With recent advances in technology, systematics are increasingly using DNA __________ data to infer evolutionary relationships and construct phylogenies.

sequencing

A character that is shared by two or more species because it originated in their most recent common ancestor is a(n) _____________________ character.

shared derived

A term used to indicate species or higher level groups, such as genera or families, is ___________.

taxon

The science of classifying organisms is termed _________.

taxonomy

A cladogram depicts a hypothesis of ____________ relationships.

evolutionary

The ___________ clock is used to determine the timing of branching events by using the fossil record or geologic events to calculate DNA divergence rates.

molecular

According to the ____________ species concept, a population should be considered a separate species if it has been evolving independently of other groups of populations.

phylogenetic

The hypothesized evolutionary relationships among species is represented by a diagram known as a(n) _____________.

phylogeny

Place the six lowest levels of the taxonomic system in hierarchical order, with the MOST inclusive level at the top and the LEAST inclusive level at the bottom. Genus Class Family Species Phylum Order

1. Phylum 2. Class 3. Order 4. Family 5. Genus 6. Species

Place the following species in order, with the species most closely related to species C at the top. Species A Species B Species D

1. Species A 2. Species D 3. Species B

What is true of shared derived characters ? A) They are more informative than ancestral characters. B) They are newer than ancestral characters on an evolutionary timescale. C) They are inherited from the most recent common ancestor of an entire group. D) Usually, each species in a group is characterized by one or a few unique shared derived characters.

A) They are more informative than ancestral characters. B) They are newer than ancestral characters on an evolutionary timescale.

According to the phylogenetic species concept, a species is a population that: A) has evolved independently of the other groups of populations B) has substantial morphological differences from other populations C) is reproductively isolated from other populations

A) has evolved independently of the other groups of populations

Only shared derived characters are instructive in determining evolutionary relationships among taxa because: A) they indicate recent evolutionary changes and are therefore exhibited in closely related taxa B) they are essential to life and therefore may not be changed over the course of evolution C) they are the most prevalent characters exhibited by members of a clade D) they are retained from a distant common ancestor and are therefore exhibited by all members of a clade

A) they indicate recent evolutionary changes and are therefore exhibited in closely related taxa

The pace of evolution is _______________. A) variable B) decreasing C) constant D) increasing

A) variable

In a cladogram, what word describes an ancestral species and all of its descendants? A) Taxon B) Clade C) Outgroup D)Synapomorphy

B) Clade

Two species may independently evolve similar characters when adapting to similar environments rather than through inheritance from a common ancestor. This process is known as _______________. A) Parallel evolution B) Convergent evolution C) Coevolution D) Divergent evolution

B) Convergent evolution

Which of the following statements are true of an outgroup? A) It diverged after all of the species in the group being studied. B) It can be used to polarize characters C) It exhibits all shared derived characters found in the group under study. D) It is closely related to the group under study, but is not a member of the group.

B) It can be used to polarize characters D) It is closely related to the group under study, but is not a member of the group.

Which of the following best describes the fossil record? A) It is incomplete, except for a few types of organisms such as horses, whales, and humans. B) It is an incomplete record of species that have existed on Earth. C) It is a complete record of species that have existed on Earth.

B) It is an incomplete record of species that have existed on Earth.

What principle proposes that the most likely phylogenetic tree is the one that is the simplest for all the characters and their states? A) Convergent Evolution B) Parsimony C) Symplesiomorphy D) Natural Selection E) Synapomorphy

B) Parsimony

What are the traditional taxonomic hierarchies based on? A) Geographic distribution B) Shared traits C) Evolutionary relationships

B) Shared traits

Which of the following are examples of homoplastic traits? A) Forelimb bones of dolphins and horses B) Wings of birds and dragonflies C) Parental care in crocodiles and birds D) Saber teeth in saber-toothed cats and marsupials E) Conducting tubes of bryophytes and angiosperm plants.

B) Wings of birds and dragonflies D) Saber teeth in saber-toothed cats and marsupials E) Conducting tubes of bryophytes and angiosperm plants.

Phylogenies provide information about: A) the future course of evolution B) how evolution occurred C) reasons for extinction D) evolutionary relationships among species

B) how evolution occurred D) evolutionary relationships among species

Similarity between species may not accurately predict evolutionary relationships due to (choose all that apply): A) Natural Selection B) the variable rate of evolution C) Evolutionary Reversal D) Convergent Evolution

B) the variable rate of evolution C) Evolutionary Reversal D) Convergent Evolution

Which are causes of homoplasy? A) Parsimony B) Divergent Evolution C) Evolutionary Reversal D) Convergent Evolution

C) Evolutionary Reversal D) Convergent Evolution

Which of the following are homologous traits ? A) Wings in birds and dragonflies B) Saber teeth in saber-toothed cats and marsupials C) Parental care in birds and crocodiles D) Conducting tubes in angiosperms and bryophytes E) Forelimb bones of horses and dolphins

C) Parental care in birds and crocodiles E) Forelimb bones of horses and dolphins

What kind of data were first used to create phylogenetic trees? A) Habitat Data B) Natural Selection Data C) Similarities in morphology D) Similarities in DNA sequences

C) Similarities in morphology

On a branching diagram, what does the joining of twigs and branches represent? A) Extinction B) Differences in classification systems C) The pattern of common ancestry

C) The pattern of common ancestry

Saber teeth in saber-toothed cats, marsupials, and nimravids are: A) homologous because they were derived from a common ancestor that also had saber teeth B) homoplastic because they were inherited from a common ancestor that also had saber teeth C) homoplastic because they evolved independently in each group as a result of convergent evolution D) homologous because they evolved independently as a result of convergent evolution

C) homoplastic because they evolved independently in each group as a result of convergent evolution

A similarity that arose prior to the most recent common ancestor of a group is called a(n): A) Derived Character B) Character State C) Homoplasmic Character D) Ancestral Character

D) Ancestral Character

What type of traits are informative for determining phylogenetic relationships? A) Only symplesiomorphies B) Both synapomorphies and symplesiomorphies C) Neither synapomorphies nor symplesiomorphies D) Only synapomorphies

D) Only synapomorphies

What is systematics? A) The study of changes in the genetic makeup of populations over time. B) The study of the relationship between genotype and phenotype. C) The science of describing, naming, and classifying organisms. D) The study of evolutionary relationships among organisms.

D) The study of evolutionary relationships among organisms.

Which of the following statements is true for all of the species that come after a branch point in a cladogram? A) They will no longer need an outgroup B) They do not share any derived characters C) They will share at least two shared derived characters D) They will share at least one shared derived character

D) They will share at least one shared derived character

As sequencing techniques have improved, scientists have begun to reassess many taxonomic groups established by traditional classification. Why? A) To make sure they have identical DNA sequences B) To make sure they share their DNA sequences. C) To make sure they are not monophyletic D) To make sure they are monophyletic.

D) To make sure they are monophyletic.

Systematists determine whether a character is ancestral or derived by using the method of _______ comparison. A) homoplasy B) parsimony C) scale D) outgroup

D) outgroup

True/False: Researchers are only interested in the pathways of evolutionary change and not the actual timing of events.

False

Match each group to the taxa it includes: Monophyletic Paraphyletic Polyphyletic

Monophyletic: the most recent common ancestor of the group and all of its descendants Paraphyletic: the most recent common ancestor of the group and some, but not all, of its descendants Polyphyletic: the most recent common ancestor of all the members of the group is not included

In this phylogeny, blue represents marine snails with dispersing larvae, and brown represents marine snails with nondispersing larvae. Based on this phylogeny, the ancestral state was most likely _______________ larvae.

dispersing

According to the phylogenetic tree shown, bats are most closely related to _________________.

giraffes

According to this phylogeny, which primate species is most closely related to humans and chimpanzees?

gorilla

Wings of birds and dragonflies, saber teeth in saber-toothed cats and marsupials, and conducting tubes in bryophytes and angiosperm plants are all examples of ____________ traits.

homoplastic

A ___________ is a shared character state that was not inherited from a common ancestor. These characters can make two species seem related when they are actually not.

homoplasy