African elephant vs Concentric Boulder Lichen

Loxodonta africana compared with Porpidia crustulata

Taxonomic Classification

Rank	African elephant	Concentric Boulder Lichen
Kingdom	Animalia (動物)	Fungi (菌界)
Phylum	Chordata (脊索動物)	Ascomycota (子嚢菌門)
Class	Mammalia (哺乳類)	Lecanoromycetes (チャシブゴケ菌綱)
Order	Proboscidea (ゾウ目)	Lecideales (Lecideales)
Family	Elephantidae (Elephants)	Lecideaceae
Genus	Loxodonta (African Elephants)	Porpidia
Species	Loxodonta africana	Porpidia crustulata

Conservation Status

African elephant

VU — Vulnerable

Population: ~415.0K

Trend: Decreasing ↓

Concentric Boulder Lichen

VU — Vulnerable

Physical Characteristics

Attribute	African elephant	Concentric Boulder Lichen
Diet	Herbivore	—
Average Lifespan	65 years	—
Average Length	6.0 m	—
Average Weight	6.0 t	—

Habitat & Geographic Range

African elephant

Habitat

Found across multiple habitat types including tropical and subtropical moist broadleaf forests, tropical and subtropical grasslands and savannas, and flooded grasslands and savannas, among 5 distinct biome types within the Afrotropic biogeographic realm. Populations are also found in montane and highland environments at higher elevations.

Range

Found in Kenya. Currently classified as Vulnerable on the IUCN Red List, this species faces significant conservation challenges across its range.

Concentric Boulder Lichen

Habitat

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

Range

Distributed across Denmark, Norway, Portugal, Sweden, and United States. Currently classified as Vulnerable on the IUCN Red List, this species faces significant conservation challenges across its range.

African elephant

地球上最大の陸上動物であるアフリカゾウは体重7,000 kgに達し、サハラ以南のサバンナ、森林、湿地に生息する。成熟した雌が群れを率いる高度に知的な社会構造を持ち、超低周波音やうなり声、接触によって意思疎通する。木を引き倒したり水飲み場を掘ったり種子を散布したりすることで生態系を形成するエンジニア種だが、象牙の密猟や生息地の喪失により個体数は減少しており、危急（VU）とされている。

Concentric Boulder Lichen

<em>Porpidia crustulata</em>, commonly known as the Concentric Boulder Lichen, is a crustose lichen in the family Porpidiaceae formed through a symbiotic relationship between a fungal partner (mycobiont) and photosynthetic green algae (photobiont). Like all crustose lichens, it grows tightly appressed to its substrate—typically siliceous or acidic rock surfaces including boulders, cliff faces, and pebbles in open, well-lit habitats—forming thin, grayish to pale thalli marked by scattered black apothecia (reproductive discs). <em>Porpidia crustulata</em> derives nutrition entirely through photosynthesis conducted by its algal partner, requiring no external organic food source. The species has been documented in Denmark, Norway, Portugal, Sweden, and the United States, suggesting a broad boreal to temperate distribution across the Northern Hemisphere. It is currently classified as Vulnerable by the IUCN, indicating significant conservation concern, likely linked to threats including air pollution, acidification, quarrying of rocky habitats, and changes in land use that reduce the availability of suitable substrates. Crustose lichens are typically slow-growing, long-lived organisms with limited capacity for rapid range shifts in response to environmental change. Biological traits such as individual lifespan, growth rates, and reproductive output remain poorly documented at the population level.