Polar bear vs Sharp-tooth smooth hound

Ursus maritimus compared with Mustelus dorsalis

Taxonomic Classification

Rank	Polar bear	Sharp-tooth smooth hound
Kingdom same	Animalia (動物)	Animalia (動物)
Phylum same	Chordata (脊索動物)	Chordata (脊索動物)
Class	Mammalia (哺乳類)	Chondrichthyes (軟骨魚綱)
Order	Carnivora (ネコ目)	Carcharhiniformes (メジロザメ目)
Family	Ursidae (Bears)	Triakidae
Genus	Ursus (Bears)	Mustelus
Species	Ursus maritimus	Mustelus dorsalis

Evolutionary Relationship

Polar bear and Sharp-tooth smooth hound share a common ancestor at the Phylum level: Chordata. (脊索動物)

Conservation Status

Polar bear

VU — Vulnerable

Population: ~26.0K

Trend: Decreasing ↓

Sharp-tooth smooth hound

VU — Vulnerable

Physical Characteristics

Attribute	Polar bear	Sharp-tooth smooth hound
Diet	Carnivore	—
Average Lifespan	25 years	—
Average Length	2.4 m	—
Average Weight	450.0 kg	—

Habitat & Geographic Range

Polar bear

Habitat

Found across multiple habitat types including temperate broadleaf and mixed forests, temperate coniferous forests, and boreal forests and taiga, among 4 distinct biome types within the Palearctic biogeographic realm. Populations are also found in montane and highland environments at higher elevations.

Range

Found in Norway. Currently classified as Vulnerable on the IUCN Red List, this species faces significant conservation challenges across its range.

Sharp-tooth smooth hound

Habitat

Typically found in marine environments from coastal waters to deep ocean.

Polar bear

地球上で最大の陸上肉食動物であるホッキョクグマは700kgを超えることがあり、カナダからロシアまでの北極海氷域全体に分布する。ワモンアザラシとヒゲアザラシを狩るために海氷に依存する高度に特化した海洋哺乳類である。広大な距離を泳ぐことができる優れた泳者でもある。脆弱種に指定されており、気候変動による急激な北極海氷の消失で個体群が深刻な圧力を受けている。