Terrestrial hypothesis

Definition

The terrestrial hypothesis suggests that certain animal traits or adaptations evolved primarily for life on land. In the context of vertebrates, this includes adaptations seen in birds for terrestrial environments.

5 Must Know Facts For Your Next Test

1. The terrestrial hypothesis explains how birds developed features like strong legs and feet for walking or running on land.
2. Many ground-dwelling birds exhibit reduced wing size, supporting the terrestrial hypothesis by prioritizing locomotion over flight.
3. Birds such as ostriches and emus are prime examples that support the terrestrial hypothesis due to their flightlessness and specialized terrestrial adaptations.
4. The development of beaks in some bird species is an adaptation linked to feeding habits on land, supporting the terrestrial hypothesis.
5. The evolution of nesting behaviors in ground birds can be explained through the terrestrial hypothesis as a strategy to avoid predators.

Review Questions

• What key physical traits do birds exhibit that support the terrestrial hypothesis?
• How do ground-dwelling birds like ostriches exemplify the terrestrial hypothesis?
• Why is the development of nesting behaviors in some bird species considered evidence for the terrestrial hypothesis?

Related terms

Flightless Birds: Birds that have lost the ability to fly through evolution, often developing strong legs for walking or running.

Beak Adaptation: Evolutionary changes in a bird's beak structure to suit specific feeding habits, often influenced by their environment.

Nesting Behavior: Habits related to where and how birds build nests, which can vary greatly depending on whether they live in trees, cliffs, or on the ground.