Answer:
Part a:
Whales and sharks share a common ancestor for superficial characteristics
Part b:
The vestigial pelvic bone of whales and dolphins indicates that they descended from an ancestor that lived on land.
Explanation:
Part a:
Whales and sharks possess similar body shapes and fin positions not because of descent from a common ancestor but due to their shared aquatic habitat. Whales share more characteristics with humans than with sharks. This indicates close phylogenetic ties (ancestral similarities) between humans and whales whereas sharks and whales have evolved independently. If they shared a common ancestor, they would have similar anatomical characters as well.
Part b:
Vestigial Structure:
A vestigial structure is an anatomical characteristic that is believed to have served a specific function for an organism in the past but as the organism evolved, the structure lost its function.
Pelvic bones are required by animals to move their lower limbs to be able to walk on land. Whales possess vestigial pelvic bones because they have evolved from an ancestor that lived on land.
I see someone answering for u
Answer: When the oxygen-rich blood gets to the cells, the cells receive the oxygen and release the carbon dioxide. The blood with less oxygen and a lot of carbon dioxide returns to the heart. Then the heart returns this blood to the lungs where carbon dioxide is released and oxygen is received.
Explanation:
Well you should know the Cardiac works the heart so that's not voluntary the smooth muscle is clarly used involuntary, so that would make it the skeletal.