Cobweb weaver vs Polar bear

Steatoda nobilis compared with Ursus maritimus

Key Differences

• Cobweb weaver is Not Evaluated while Polar bear is Vulnerable.

Taxonomic Classification

Rank	Cobweb weaver	Polar bear
Kingdom same	Animalia (Animals)	Animalia (Animals)
Phylum	Arthropoda (Arthropods)	Chordata (Chordates)
Class	Arachnida (Arachnids)	Mammalia (Mammals)
Order	Araneae (Araneae)	Carnivora (Carnivorans)
Family	Theridiidae	Ursidae (Bears)
Genus	Steatoda	Ursus (Bears)
Species	Steatoda nobilis	Ursus maritimus

Evolutionary Relationship

Cobweb weaver and Polar bear share a common ancestor at the Kingdom level: Animalia. (Animals)

Conservation Status

Cobweb weaver

NE — Not Evaluated

Polar bear

VU — Vulnerable

Population: ~26.0K

Trend: Decreasing ↓

Physical Characteristics

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

Habitat & Geographic Range

Cobweb weaver

Habitat

Typically found in terrestrial habitats from forests to deserts.

Range

Widely distributed across Europe (7 countries), North America (United States), and South America (Ecuador).

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.

Cobweb weaver

The noble false widow (Steatoda nobilis) is a theridiid spider that has attracted considerable media attention in the British Isles and along the Atlantic coast of Europe due to its painful but rarely dangerous bite and its rapid range expansion facilitated by human activity. Originally native to the Canary Islands and Madeira, the species arrived in southern England during the 19th century, likely via banana shipments, and has since spread northward through Britain and westward into Ireland, while also establishing populations along the Iberian Peninsula and Atlantic France. Females are robust, with a dark brown carapace and a distinctive cream-colored pattern on the bulbous abdomen that varies between individuals; females reach 8.5–14 millimeters in body length, making this one of the larger European theridiids. The species constructs persistent, tangled cobwebs in sheltered locations outside buildings—under window ledges, in door frames, and in garden walls—as well as within homes in cooler seasons. It is a generalist predator, capturing insects and other invertebrates, and has been reported to occasionally subdue prey considerably larger than itself, including small lizards. Steatoda nobilis venom produces steatodism, which can cause localized pain, swelling, and in rare cases systemic symptoms. Its conservation status has not been formally assessed, but its expanding range demonstrates considerable resilience.

Polar bear

The largest land carnivore on Earth, polar bears can exceed 700 kg and are found across Arctic sea ice from Canada to Russia. Highly specialized marine mammals that rely on sea ice to hunt ringed and bearded seals. Excellent swimmers capable of covering vast distances in open water. Listed as Vulnerable, with populations under severe pressure from rapid Arctic sea ice loss due to climate change.