Flightless birds on island often have relative on the mainland that can fly. The island species presumably evolved from fliers that, in the absences of predators, lost their ability to fly. Many island population of flightless birds are in decline because rats have been introduced to their previously isolated island habits. Despite current selection pressure in favor of flight, no flightless island bird species has regained the ability to fly. Why is this unlikely to happen?

Flightless birds on island often have relative on the mainland that can fly. The island species presumably evolved from fliers that, in the absences of predators, lost their ability to fly. Many island population of flightless birds are in decline because rats have been introduced to their previously isolated island habits. Despite current selection pressure in favor of flight, no flightless island bird species has regained the ability to fly. Why is this unlikely to happen?

BIOLOGY:CONCEPTS+APPL.(LOOSELEAF)

10th Edition

ISBN:9781305967359

Author:STARR

Publisher:STARR

Chapter39: Animal Behavior

Section: Chapter Questions

Problem 1CT

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