Polar bear vs sun shell

Ursus maritimus compared with Astraea heliotropium

Key Differences

• Polar bear is Vulnerable while sun shell is Least Concern.

Taxonomic Classification

Rank	Polar bear	sun shell
Kingdom same	Animalia (動物)	Animalia (動物)
Phylum	Chordata (脊索動物)	Mollusca (軟体動物)
Class	Mammalia (哺乳類)	Gastropoda (腹足綱)
Order	Carnivora (ネコ目)	Trochida (Trochida)
Family	Ursidae (Bears)	Turbinidae
Genus	Ursus (Bears)	Astraea
Species	Ursus maritimus	Astraea heliotropium

Evolutionary Relationship

Polar bear and sun shell share a common ancestor at the Kingdom level: Animalia. (動物)

Conservation Status

Polar bear

VU — Vulnerable

Population: ~26.0K

Trend: Decreasing ↓

sun shell

LC — Least Concern

Physical Characteristics

Attribute	Polar bear	sun shell
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.

sun shell

Habitat

Typically found in terrestrial and aquatic habitats including forests and freshwater.

Range

Found in New Zealand.

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。