Here's why:
* Chordates are a phylum of animals that share several key characteristics at some point in their development:
* Notochord: A flexible rod that supports the body.
* Dorsal hollow nerve cord: A tube of nerve tissue that runs along the back.
* Pharyngeal slits: Openings in the throat that are used for filter feeding in some species.
* Post-anal tail: A tail that extends beyond the anus.
* Polar bears are mammals, and all mammals are vertebrates.
* Vertebrates are a subphylum of Chordates that have a backbone (spinal column) made of vertebrae.
Therefore, since polar bears are vertebrates, they are also Chordates.