Common Oak Fern vs koala

Gymnocarpium dryopteris compared with Phascolarctos cinereus

Key Differences

Common Oak Fern is Critically Endangered while koala is Vulnerable.

Taxonomic Classification

Rank	Common Oak Fern	koala
Kingdom	Plantae (植物)	Animalia (動物)
Phylum	Tracheophyta	Chordata (脊索動物)
Class	Polypodiopsida (ウラボシ綱)	Mammalia (哺乳類)
Order	Polypodiales (ウラボシ目)	Diprotodontia (カンガルー目)
Family	Cystopteridaceae	Phascolarctidae (Koalas)
Genus	Gymnocarpium	Phascolarctos (Koalas)
Species	Gymnocarpium dryopteris	Phascolarctos cinereus

Conservation Status

Common Oak Fern

CR — Critically Endangered

koala

VU — Vulnerable

Population: ~100.0K

Trend: Decreasing ↓

Physical Characteristics

Attribute	Common Oak Fern	koala
Diet	—	Herbivore
Average Lifespan	—	15 years
Average Length	—	75 cm
Average Weight	—	10.0 kg

Habitat & Geographic Range

Common Oak Fern

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 across Europe (6 countries) and North America (Canada, United States). Currently classified as Critically Endangered on the IUCN Red List, this species faces significant conservation challenges across its range.

koala

Habitat

Typically found in grasslands, forests, and vegetated habitats.

Range

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

Common Oak Fern

Gymnocarpium dryopteris, the common oak fern, is a delicate terrestrial fern in the family Cystopteridaceae (or Woodsiaceae, depending on classification). Despite its common name, the species is not specifically associated with oak trees; rather, it typically grows in cool, moist, shaded environments including boreal and mixed forests, rocky woodland slopes, stream banks, and shaded cliff faces. Gymnocarpium dryopteris spreads by rhizomes and forms low, spreading colonies with characteristic triangular, three-pinnate fronds that emerge from a slender creeping rootstock. Its geographic range spans Europe and North America, with populations in cool temperate and boreal zones. The species is currently assessed as Critically Endangered in certain regional assessments, suggesting that particular populations face severe decline, likely due to habitat loss, forest fragmentation, and altered hydrology, even if the species retains a broader global range. Biological traits such as lifespan, body size, and diet remain poorly documented at a standardized population level. Gymnocarpium dryopteris is a characteristic indicator of undisturbed cool woodland habitats and is valued for both its ecological role in forest understoreys and its aesthetic appeal.

koala

オーストラリア東部・南東部を代表する有袋類で、体重は最大15kgに達し、低カロリーのユーカリの葉食から得るエネルギーを節約するために1日最大22時間を睡眠に費やす。他の哺乳類の多くを死に至らしめる有毒なユーカリ成分を処理するために高度に特化しており、解毒に特別に適応した腸内微生物叢を持つ。クラミジア感染症、生息地の伐採、気候変動により個体数が激減し、2022年に絶滅危惧種に指定された。