Discovering Homologous Structures: Bat Wings and Bird Wings
Which of the following are homologous?
a. bat wings and fly wings
b. bat wings and bird legs
c. bat wings and mouse legs
d. bat wings and human feet
e. bat wings and bird wings
Answer:
Homologous structures, like bat wings and bird wings, provide evidence for common ancestry and evolutionary relationships between organisms.
Homologous structures are similar body parts in different organisms that have a common evolutionary origin. They may have different functions but are structurally similar.
Bat wings and bird wings are considered homologous because they share a common structure. Both bat wings and bird wings have a similar bone structure with elongated fingers and a membrane of skin stretched between them. Despite having different functions (bats use their wings for flying, while birds use their wings for both flying and balance), the underlying structure is similar, indicating a common ancestry.
In contrast, the other options are not homologous:
- a. Bat wings and fly wings: Although both are wings, fly wings and bat wings have different structures. Fly wings are made up of a thin, transparent membrane, while bat wings have elongated fingers and a membrane of skin.
- b. Bat wings and bird legs: Bat wings and bird legs are completely different in terms of structure and function. Bat wings are used for flight, while bird legs are used for walking and perching.
- c. Bat wings and mouse legs: Similarly, bat wings and mouse legs are dissimilar in structure and function. Bat wings are adapted for flight, while mouse legs are used for running and climbing.
- d. Bat wings and human feet: Bat wings and human feet are also completely different. Bat wings are used for flight, while human feet are used for walking and running.
Homologous structures play a crucial role in understanding the evolutionary history of living organisms. By comparing and analyzing these structures, scientists can unravel the intricate relationships and connections between different species.