Question

Evelyn is digging in a riverbank on the Peace River. She finds a fossil that looks like whalebone. After further digging, she finds the rest of the skeleton. While putting this skeleton together, she ends up with a few extra bones, including hip and leg bones that were too small for this animal. What would be the possible reason for these bones in this organism?

These bones are vestigial structures showing relatedness to ancestral organisms.

These bones are analogous structures related to dolphin species.

These bones give molecular evidence for relatedness to other organisms.

These bones are giving evidence to the geographical distribution of this organism.

Answer 1

These are vestigial structures showing relatedness to ancestral organisms.

Explanation: Small hip/leg bones in an otherwise fully aquatic fossil are remnants of ancestors that walked on land. They are vestigial (homologous) structures indicating evolutionary relatedness, not analogous structures, molecular evidence, or biogeographical evidence.