What concept describes how different organisms can have similar structures due to common ancestry?

What concept describes how different organisms can have similar structures due to common ancestry?

• A. Analogous structures
• B. Homologous structures
• C. Convergent evolution
• D. Adaptive radiation

Answer: (B)

The concept that describes how different organisms can have similar structures due to common ancestry is known as homologous structures. These structures are formed from the same embryonic tissues and are indicative of a shared evolutionary history. For example, the forelimbs of humans, whales, and bats all have a similar underlying skeletal structure, reflecting their descent from a common ancestor, even though their functions and outward appearances may differ significantly. This similarity in structure despite differing functions demonstrates how evolution can modify a fundamental design to suit specific environmental needs while maintaining an underlying genetic connection. In contrast, analogous structures arise when different species develop similar traits or functionalities independently, often due to similar environmental pressures, rather than from a common ancestor. This reflects convergent evolution, where unrelated organisms adapt similarly, but it does not indicate shared ancestry. Adaptive radiation refers to the rapid evolution of diversely adapted species from a common ancestor when they exploit different environments. These concepts collectively enhance our understanding of evolutionary biology, but the similarity due to common ancestry specifically points to homologous structures.

The concept that describes how different organisms can have similar structures due to common ancestry is known as homologous structures. These structures are formed from the same embryonic tissues and are indicative of a shared evolutionary history. For example, the forelimbs of humans, whales, and bats all have a similar underlying skeletal structure, reflecting their descent from a common ancestor, even though their functions and outward appearances may differ significantly. This similarity in structure despite differing functions demonstrates how evolution can modify a fundamental design to suit specific environmental needs while maintaining an underlying genetic connection.

In contrast, analogous structures arise when different species develop similar traits or functionalities independently, often due to similar environmental pressures, rather than from a common ancestor. This reflects convergent evolution, where unrelated organisms adapt similarly, but it does not indicate shared ancestry. Adaptive radiation refers to the rapid evolution of diversely adapted species from a common ancestor when they exploit different environments. These concepts collectively enhance our understanding of evolutionary biology, but the similarity due to common ancestry specifically points to homologous structures.