Brown Rat vs common Atlantic octopus

Rattus norvegicus compared with Octopus vulgaris

Key Differences

• Brown Rat is Least Concern while common Atlantic octopus is Not Evaluated.

Taxonomic Classification

Rank	Brown Rat	common Atlantic octopus
Kingdom same	Animalia (Animals)	Animalia (Animals)
Phylum	Chordata (Chordates)	Mollusca (Mollusks)
Class	Mammalia (Mammals)	Cephalopoda (Cephalopods)
Order	Rodentia (Rodents)	Octopoda (Octopuses)
Family	Muridae (Mice & Rats)	Octopodidae (Common Octopuses)
Genus	Rattus	Octopus (Octopuses)
Species	Rattus norvegicus	Octopus vulgaris

Evolutionary Relationship

Brown Rat and common Atlantic octopus share a common ancestor at the Kingdom level: Animalia. (Animals)

Conservation Status

Brown Rat

LC — Least Concern

common Atlantic octopus

NE — Not Evaluated

Trend: Stable →

Physical Characteristics

Attribute	Brown Rat	common Atlantic octopus
Diet	—	Carnivore
Average Lifespan	—	2 years
Average Length	—	60 cm
Average Weight	—	5.0 kg

Habitat & Geographic Range

Brown Rat

Habitat

Found across multiple habitat types including tropical and subtropical moist broadleaf forests, tropical and subtropical dry broadleaf forests, and tropical and subtropical grasslands and savannas, among 10 distinct biome types. Populations are also found in montane and highland environments at higher elevations.

Range

Widely distributed across Africa (11 countries), Asia (15 countries), Europe (41 countries), North America (16 countries), Oceania and the Pacific (10 countries), and South America (10 countries).

common Atlantic octopus

Habitat

Typically found in diverse ecosystems where prey species are available.

Range

Distributed across Chile, Denmark, Norway, Portugal, and Sweden.

Brown Rat

Brown Rat (Rattus norvegicus) is classified as Least Concern (LC) on the IUCN Red List. Widespread and abundant across its range, with stable populations and no immediate conservation concerns.

common Atlantic octopus

One of the most studied invertebrates in neuroscience and behavioral biology, common octopuses inhabit rocky reefs and seafloors in tropical and temperate coastal waters globally. Highly intelligent with distributed nervous systems — two-thirds of their 500 million neurons reside in their arms — they demonstrate tool use, problem-solving, and individual personalities. Masters of camouflage, they change skin color and texture in milliseconds. They have three hearts, blue copper-based blood, and extremely short lifespans of 1–2 years.

Shared Countries

Both species can be found in 5 countries:

🇨🇱 Chile 🇩🇰 Denmark 🇳🇴 Norway 🇵🇹 Portugal 🇸🇪 Sweden