Brittle Naiad vs Polar bear

Najas minor compared with Ursus maritimus

Key Differences

Brittle Naiad is Critically Endangered while Polar bear is Vulnerable.

Taxonomic Classification

Rank	Brittle Naiad	Polar bear
Kingdom	Plantae (植物)	Animalia (動物)
Phylum	Magnoliophyta (被子植物門)	Chordata (脊索動物)
Class	Liliopsida (単子葉植物綱)	Mammalia (哺乳類)
Order	Alismatales (オモダカ目)	Carnivora (ネコ目)
Family	Hydrocharitaceae	Ursidae (Bears)
Genus	Najas	Ursus (Bears)
Species	Najas minor	Ursus maritimus

Conservation Status

Brittle Naiad

CR — Critically Endangered

Polar bear

VU — Vulnerable

Population: ~26.0K

Trend: Decreasing ↓

Physical Characteristics

Attribute	Brittle Naiad	Polar bear
Diet	—	Carnivore
Average Lifespan	—	25 years
Average Length	—	2.4 m
Average Weight	—	450.0 kg

Habitat & Geographic Range

Brittle Naiad

Habitat

Found across multiple habitat types including tropical and subtropical moist broadleaf forests, tropical and subtropical coniferous forests, and temperate broadleaf and mixed forests, among 9 distinct biome types spanning the Indomalayan and Palearctic realms. Populations are also found in montane and highland environments at higher elevations.

Range

Widely distributed across Asia (Pakistan, Taiwan), Europe (4 countries), and North America (Canada, United States). Currently classified as Critically Endangered on the IUCN Red List, this species faces significant conservation challenges across its 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.

Brittle Naiad

The Brittle Naiad (Najas minor) is a species in the genus Najas. It is currently classified as Critically Endangered on the IUCN Red List. Found across multiple habitat types including tropical and subtropical moist broadleaf forests, tropical and subtropical coniferous forests, and temperate broadleaf and mixed forests, among 9 distinct biome types spanning the Indomalayan an

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。