Columbia Water-Meal vs Polar bear

Wolffia columbiana compared with Ursus maritimus

Key Differences

• Columbia Water-Meal is Least Concern while Polar bear is Vulnerable.

Taxonomic Classification

Rank	Columbia Water-Meal	Polar bear
Kingdom	Plantae (植物)	Animalia (动物界)
Phylum	Magnoliophyta (木兰植物门)	Chordata (脊索动物门)
Class	Liliopsida (百合纲)	Mammalia (哺乳動物)
Order	Alismatales (泽泻目)	Carnivora (食肉目)
Family	Araceae	Ursidae (Bears)
Genus	Wolffia	Ursus (Bears)
Species	Wolffia columbiana	Ursus maritimus

Conservation Status

Columbia Water-Meal

LC — Least Concern

Polar bear

VU — Vulnerable

Population: ~26.0K

Trend: Decreasing ↓

Physical Characteristics

Attribute	Columbia Water-Meal	Polar bear
Diet	—	Carnivore
Average Lifespan	—	25 years
Average Length	—	2.4 m
Average Weight	—	450.0 kg

Habitat & Geographic Range

Columbia Water-Meal

Habitat

Typically found in grasslands, wetlands, forests, and cultivated landscapes.

Range

Widely distributed across Asia (India), Europe (4 countries), North America (Canada, United States), and South America (Brazil, Colombia).

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.

Columbia Water-Meal

<em>Wolffia columbiana</em> is a diminutive aquatic flowering plant belonging to the family Araceae, widely recognized as one of the smallest known vascular plants on Earth. It inhabits still or slow-moving freshwater environments, including ponds, lakes, ditches, and quiet backwaters, where it floats freely at or just below the water surface. The species occurs across a broad geographic range spanning the Americas. As a rootless, leafless organism, <em>W. columbiana</em> consists of a tiny oval thallus, measuring only a fraction of a millimeter in diameter, which carries out photosynthesis directly through its green surface tissue. Reproduction is primarily vegetative, with daughter plants budding from a specialized pouch on the parent thallus, enabling rapid population expansion under favorable conditions. The species is assessed as Least Concern on the IUCN Red List, reflecting its wide distribution and tolerance of varied freshwater conditions.

Polar bear

北极熊是地球上最大的陆地食肉动物，体重可超过700千克，分布于从加拿大到俄罗斯的北极海冰区。是高度特化的海洋哺乳动物，依赖海冰捕猎环斑海豹和髯海豹。是优秀的游泳者，能够横渡广阔的开阔水域。被列为易危种，因气候变化导致北极海冰迅速减少，种群正受到严重威胁。