Question

From an evolutionary perspective, front flippers in dolphins and human arms would be considered ____________ structures because they did evolve from the same feature in their common ancestor.

a) Homologous
b) Analogous
c) Vestigial
d) Convergent

Answer 1

Front flippers in dolphins and human arms are a) homologous structures that evolved from a feature in their common ancestor, while the similar body shapes of dolphins and fish are examples of analogous traits resulting from convergent evolution.

Step-by-step explanation:

From an evolutionary perspective, front flippers in dolphins and human arms would be considered homologous structures because they did evolve from the same feature in their common ancestor. The term 'homologous' is used to describe structures that have a similar evolutionary origin and embryonic development, even though their functions may differ. For example, although the front flippers of dolphins and the arms of humans are used for different purposes, they share common structural elements inherited from a common ancestor, such as the arrangement of bones. On the other hand, the body shapes of dolphins and fish are analogous traits. This is because, although both have similar streamlined bodies that are beneficial for moving through water, they have evolved separately in different evolutionary lineages. Dolphins are mammals and fish belong to a different group of vertebrates, which means their similar body shapes are the result of convergent evolution, where unrelated species develop similar traits independently due to comparable environmental pressures.