Entry Exam Category: High School Equivalency Exams
Course: General Education Development (GED)
Exam: GED Science and Practice Test
Practice Question
Extract
Various species of birds from the genus Agaporis possess differing behaviors. These behaviors
differ in a way that can be used to infer how the species are related and how they have evolved
over time.
For example, the three lovebird species considered to be the most primitive all build simple nests
in preexisting cavities. The three middle species all build elaborate nests with tops, and one even
digs out a cavity for the nest. The four modern species build cuplike nests: These nests are more
complex than those built by the primitive species but less complex than those built by the middle
species.
William Dilger conducted an investigation to show that the nest-building behaviors of these birds
were genetic rather than learned behaviors. In his investigation, Dilger used two different species
of lovebird that readily mate with each other-Fischer's lovebird and the peach-faced lovebird.
Fischer's lovebird is a species of moder lovebird while the peach-faced lovebird is a slightly more
primitive species.
Fischer's lovebird carries small pieces of nesting material in its beak. The small size of the nesting
material is the reason for the simpler cuplike nests of Fischer's lovebird. The peach-faced lovebird
cuts long strips of nesting material, which is then tucked into the feathers on the back of the bird.
These long strips of nesting material will often fall out of the bird's feathers. However, the long
strips of material allow the peach-faced lovebird to build an elaborate nest.
The hybrid offspring of these two species has difficulty building nests. The hybrid offspring will cut
long strips of material like its peach-faced parent. However, the hybrid offspring will attempt to
carry the material in its beak and have difficulty flying. If it does attempt to place the material in
the feathers of its back, the material falls out because the bird does not properly secure the
material in its feathers.
differ in a way that can be used to infer how the species are related and how they have evolved
over time.
For example, the three lovebird species considered to be the most primitive all build simple nests
in preexisting cavities. The three middle species all build elaborate nests with tops, and one even
digs out a cavity for the nest. The four modern species build cuplike nests: These nests are more
complex than those built by the primitive species but less complex than those built by the middle
species.
William Dilger conducted an investigation to show that the nest-building behaviors of these birds
were genetic rather than learned behaviors. In his investigation, Dilger used two different species
of lovebird that readily mate with each other-Fischer's lovebird and the peach-faced lovebird.
Fischer's lovebird is a species of moder lovebird while the peach-faced lovebird is a slightly more
primitive species.
Fischer's lovebird carries small pieces of nesting material in its beak. The small size of the nesting
material is the reason for the simpler cuplike nests of Fischer's lovebird. The peach-faced lovebird
cuts long strips of nesting material, which is then tucked into the feathers on the back of the bird.
These long strips of nesting material will often fall out of the bird's feathers. However, the long
strips of material allow the peach-faced lovebird to build an elaborate nest.
The hybrid offspring of these two species has difficulty building nests. The hybrid offspring will cut
long strips of material like its peach-faced parent. However, the hybrid offspring will attempt to
carry the material in its beak and have difficulty flying. If it does attempt to place the material in
the feathers of its back, the material falls out because the bird does not properly secure the
material in its feathers.
Which hypothesis was Dilger testing in his experiment?
Answer Choices
- A: If hybrid offspring have a mixture of behaviors, then the species are within the same genus.
- B: If a hybrid offspring carries nesting material in its beak, then it is more closely related to modern lovebirds.
- C: If behavior in lovebirds is genetic, then a hybrid offspring will display a mixture of behaviors.
- D: If lovebird species can interbreed, then a hybrid offspring will have a mixture of behaviors.
Correct Answer: C
Rationale: Dilger’s experiment tested whether nest-building behaviors are genetic, shown by hybrid offspring displaying mixed behaviors.