Final answer:
Homologous traits are inherited from a common ancestor and may perform different functions across species. While analogous traits arise independently in different species due to environmental pressures and are not indicative of a common ancestry.
Step-by-step explanation:
Homologous traits are characteristics inherited from a common ancestor. These traits may evolve to perform different functions in various species, even though they have the same evolutionary origins. For example, the limbs of mammals are homologous structures that have adapted over time to serve different purposes, such as wings in bats for flying and flippers in whales for swimming. This demonstrates descent with modification. Importantly, homologous traits can be used to build phylogenetic trees, which help scientists trace the evolutionary paths of different species.
In contrast, analogous traits arise when unrelated species develop similar characteristics independently, usually due to similar environmental pressures. These are not inherited from a common ancestor and do not indicate a close evolutionary relationship. This distinction is essential when decoding the phylogeny of organisms.
Therefore, the answer to the student's question is that homologous traits are inherited from a common ancestor, but they do not always perform the same function in different species.