Common Boulder Lichen vs Polar bear

Porpidia macrocarpa compared with Ursus maritimus

Key Differences

Common Boulder Lichen is Near Threatened while Polar bear is Vulnerable.

Taxonomic Classification

Rank	Common Boulder Lichen	Polar bear
Kingdom	Fungi (Fungi)	Animalia (Animals)
Phylum	Ascomycota (Sac Fungi)	Chordata (Chordates)
Class	Lecanoromycetes (Lecanoromycetes)	Mammalia (Mammals)
Order	Lecideales (Lecideales)	Carnivora (Carnivorans)
Family	Lecideaceae	Ursidae (Bears)
Genus	Porpidia	Ursus (Bears)
Species	Porpidia macrocarpa	Ursus maritimus

Conservation Status

Common Boulder Lichen

NT — Near Threatened

Polar bear

VU — Vulnerable

Population: ~26.0K

Trend: Decreasing ↓

Physical Characteristics

Attribute	Common Boulder Lichen	Polar bear
Diet	—	Carnivore
Average Lifespan	—	25 years
Average Length	—	2.4 m
Average Weight	—	450.0 kg

Habitat & Geographic Range

Common Boulder Lichen

Habitat

Native to Europe and North America and South America, inhabiting ecosystems characteristic of the region.

Range

Widely distributed across Europe (4 countries), North America (United States), and South America (Colombia). Listed as Near Threatened, this species requires ongoing monitoring to prevent population decline.

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 Boulder Lichen

The common boulder lichen (<em>Porpidia macrocarpa</em>) is a crustose lichen species with a wide distribution across Europe and the Americas, recorded in Colombia, Denmark, Norway, Portugal, Sweden, and the United States. This species typically inhabits siliceous rock surfaces in a variety of exposed terrestrial environments across both North and South America and Europe. The common boulder lichen is classified as Near Threatened on the IUCN Red List, suggesting that its populations face potential pressures and require monitoring. As a slow-growing crustose lichen, it often colonizes hard rock substrates including granite and quartzite, forming a close symbiotic relationship between its fungal and algal components. It plays an important role in the early stages of soil formation through the gradual weathering of rock surfaces. Biological traits of this species remain poorly documented in the scientific literature.

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.