Question

Some snakes, such as those from the python family, have structures called pelvic spurs. Pelvic spurs are reduced forms of the leg bones of these snakes' ancient ancestors. Which term best describes pelvic spurs?

Multiple choice question.
A) Vestigial structure
B) Derived trait
C) Analogous structure
D) Ancestral trait

Answer 1

Pelvic spurs in snakes such as those from the python family are vestigial structures, which are reduced in size due to evolutionary changes and typically do not serve a significant purpose in the current form of the organism,the correct option is A).

Step-by-step explanation:

The pelvic spurs in snakes from the python family are best described as vestigial structures. Vestigial structures are parts of an organism that are reduced in size and often serve no significant purpose in the current form of the organism but are retained due to their presence in the organism's evolutionary ancestors.

For example, the human tailbone or appendix, the hind leg bones in whales, and wings on flightless birds are all vestigial structures. These structures provide evidence of evolution, suggesting that an organism changed from using the structure to not using it, indicating descent from a common ancestor.

Vestigial structures might shrink in size because maintaining a full-sized, unused structure would waste an organism's resources like energy and nutrients thereby reducing its fitness. In the case of snakes with pelvic spurs, these remnants of ancient leg bones reflect their evolutionary history from ancestors that had legs.