Why is animal the dolphin?

The question "Why is animal the dolphin?" doesn't make grammatical sense. It's likely you're asking one of the following:

* Why is the dolphin an animal? This is a simple question! Dolphins are animals because they share the characteristics of all animals, including being multicellular, eukaryotic organisms that obtain nutrients by consuming other organisms.

* Why is the dolphin considered an animal? This question explores how we classify dolphins. We classify dolphins as animals based on their biological characteristics, like their anatomy, physiology, and behavior.

* Why is the dolphin a special animal? This is a more subjective question. Dolphins are considered special for many reasons, including their intelligence, social behavior, playful nature, and ability to communicate with complex sounds.

* Why is the dolphin the most interesting/important/etc. animal? This question invites personal opinions and depends on what criteria you're using to judge animals.

Please clarify your question so I can provide you with a more accurate and helpful answer!