common European cockle vs Polar bear

Cerastoderma edule compared with Ursus maritimus

Key Differences

common European cockle is Least Concern while Polar bear is Vulnerable.

Taxonomic Classification

Rank	common European cockle	Polar bear
Kingdom same	Animalia (動物)	Animalia (動物)
Phylum	Mollusca (軟体動物)	Chordata (脊索動物)
Class	Bivalvia (二枚貝)	Mammalia (哺乳類)
Order	Cardiida (Cardiida)	Carnivora (ネコ目)
Family	Cardiidae	Ursidae (Bears)
Genus	Cerastoderma	Ursus (Bears)
Species	Cerastoderma edule	Ursus maritimus

Evolutionary Relationship

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

表示 Kingdom: Animalia

Conservation Status

common European cockle

LC — Least Concern

Polar bear

VU — Vulnerable

Population: ~26.0K

Trend: Decreasing ↓

Physical Characteristics

Attribute	common European cockle	Polar bear
Diet	—	Carnivore
Average Lifespan	—	25 years
Average Length	—	2.4 m
Average Weight	—	450.0 kg

Habitat & Geographic Range

common European cockle

Habitat

Native to Europe, inhabiting ecosystems characteristic of the region.

Range

Distributed across Belgium, Denmark, Iceland, Norway, and Sweden.

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.

common European cockle

<em>Cerastoderma edule</em>, the common European cockle, is an intertidal bivalve mollusc in the family Cardiidae, classified as Least Concern by the IUCN Red List. The species is native to European coastal waters and has been documented in Belgium, Denmark, Iceland, Norway, and Sweden, where it typically inhabits sandy and muddy intertidal and shallow subtidal sediments in estuaries, bays, and open coastlines. <em>Cerastoderma edule</em> is a filter feeder, drawing in seawater through its siphons to extract phytoplankton, bacteria, and organic particles. It is recognized by its distinctive ribbed, cream-colored shell with radiating ridges and concentric growth lines. Cockles are a keystone species in many European coastal ecosystems, providing an important food source for shorebirds such as oystercatchers and knots, predatory fish, crabs, and starfish. The species also supports one of the most commercially significant shellfish fisheries in Europe, with large-scale harvesting operations in the UK, the Netherlands, and Ireland. Dense cockle beds stabilize intertidal sediments and contribute to benthic productivity. Population dynamics are closely linked to sea surface temperature, salinity, and sediment availability, making this species a useful indicator of estuarine ecosystem health. Biological traits of this species remain poorly documented in the scientific literature.

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。