Question

you are having a discussion with your friend on how evolutionary history is used to classify species. your friend believes that dolphins and sharks should be classified in the same family because they both have flippers/fins and the same type of streamlined body. how would you answer your friend?

Answer 1

That is a result of convergent evolution

Step-by-step explanation:

Convergent Evolution is the development of similar adaptations by unrelated species in order to serve similar purposes in the environment. Much like butterflies and birds both have wings to fly, but aren't closely related since the wings developed long after their evolutionary lines diverged from the last common ancestor.

Dolphins and sharks both have fins, but only dolphins have flippers. Flippers contain bones very similar to human arm bones whereas shark fins consist of solid cartilage. These different structures evolved independently to allow these animals to swim in the ocean and are another example of convergent evolution.