On the tree of life, plants and animals occupy a relatively small branch that arose fairly recently.
Correct Answer
True
True. The three domains branch from one common origin, and plants and animals, including humans, make up a small, more recent branch.
Category: Phylogeny and Systematics
Question 2
Scientists treat phylogenetic trees as fixed facts that new data cannot change.
Correct Answer
False
False. Phylogenetic trees are hypotheses about the past, and they are revised as new species and new fossil, structural and molecular data are found.
Category: Phylogeny and Systematics
Question 3
Systematists build phylogenetic trees using fossils, body structure and molecular data such as DNA sequences.
Correct Answer
True
True. Morphological and fossil evidence is combined with molecular data, and trees built from different data sets are compared to reconstruct relationships.
Category: Phylogeny and Systematics
Question 4
In the Linnaean system, a genus contains several families.
Correct Answer
False
False. A family contains one or more genera, because family is the more inclusive level. Each genus in turn contains one or more species.
Category: Levels of Classification
Question 5
In a scientific name such as Canis lupus, the genus name is capitalized and the species name begins with a lowercase letter.
Correct Answer
True
True. Taxon names are capitalized except the species name, and both genus and species names are written in italics.
Category: Levels of Classification
Question 6
Organisms placed in the same class are more closely related than organisms placed in the same genus.
Correct Answer
False
False. Organisms grow more closely related at each lower level, so members of the same genus are more closely related than members of the same, broader class.
Category: Levels of Classification
Question 7
Dogs and wolves can interbreed and produce viable offspring.
Correct Answer
True
True. Dogs and wolves interbreed readily and produce fertile offspring, which is why many biologists classify the domestic dog as a subspecies of the wolf, though some references list it as a separate species.
Category: Levels of Classification
Question 8
Dogs, plants and fungi are all classified in the domain Eukarya.
Correct Answer
True
True. Dogs, plants, fungi and protists all have eukaryotic cells and share the domain Eukarya, though they are placed in different kingdoms.
Category: Levels of Classification
Question 9
Of two sister taxa, one is the direct ancestor of the other.
Correct Answer
False
False. Sister taxa both descend from a shared ancestor at their branch point, and that ancestor is usually extinct. Neither living lineage gave rise to the other.
Category: Phylogenetic Trees
Question 10
Important character changes, such as the appearance of a new trait, can be marked on a phylogenetic tree at the point where they arose.
Correct Answer
True
True. Trees often label the branch or branch point where a trait such as legs or the amniotic egg first appeared, showing which lineages inherited it.
Category: Phylogenetic Trees
Question 11
On the vertebrate phylogenetic tree, the amniotic egg appears earlier than the vertebral column.
Correct Answer
False
False. The vertebral column arose first and is shared by all vertebrates. The amniotic egg arose later, in the ancestor of reptiles and mammals.
Category: Phylogenetic Trees
Question 12
Once vertebrates appeared, invertebrate lineages stopped evolving.
Correct Answer
False
False. A new branch on a tree does not mean evolution halted elsewhere. Invertebrate lineages have continued to evolve alongside vertebrates.
Category: Limits of Phylogenetic Trees
Question 13
Humans and chimpanzees share the great majority of their genes yet differ clearly in features such as jaw shape and limb proportions.
Correct Answer
True
True. Their genetic similarity reflects close relationship, while their visible differences show that a few genetic changes can produce large anatomical effects.
Category: Limits of Phylogenetic Trees
Question 14
The more similar two species' DNA sequences are, the more distantly related they are assumed to be.
Correct Answer
False
False. Molecular systematics assumes the opposite: closer similarity in DNA or protein sequences indicates a closer evolutionary relationship.
Category: Molecular Systematics
Question 15
Rapidly changing DNA sequences are most useful for sorting out relationships among closely related species.
Correct Answer
True
True. Fast-changing sequences accumulate differences quickly, so they can separate species that diverged recently, while slow-changing genes are reserved for distant groups.
Category: Molecular Systematics
Question 16
Insect wings and bird wings develop from the same embryonic origin.
Correct Answer
False
False. Insect and bird wings develop from different embryonic tissues, so they are analogous structures that evolved independently rather than from a winged common ancestor.
Category: Homologous and Analogous Traits
Question 17
The streamlined body shapes of fish and whales are an example of similarity produced by convergent evolution.
Correct Answer
True
True. Fish and whales are distantly related, but life in water favored similar streamlined forms in both, an analogous similarity rather than one inherited from a common ancestor.
Category: Homologous and Analogous Traits
Question 18
Cladistics assumes that speciation usually splits one species into three or more species at once.
Correct Answer
False
False. Cladistics assumes that speciation splits one species into two at a time, a useful simplification for building trees.
Category: Cladistics
Question 19
A shared ancestral character is present in all members of a group, so it does not help sort out relationships within that group.
Correct Answer
True
True. Because every member has it, a shared ancestral character cannot distinguish subgroups. Shared derived characters, found in only some members, do that work.
Category: Cladistics
Question 20
Before Darwin, naturalists designed classification groups specifically to reflect evolutionary relationships.
Correct Answer
False
False. Before Darwin, organisms were sometimes grouped by arbitrary similarities. Only after the theory of evolution did classification aim to reflect common ancestry.
Category: Levels of Classification