Central Andes Oldfield Mouse vs Common Loon

Thomasomys contradictus compared with Gavia immer

Key Differences

• Central Andes Oldfield Mouse is Data Deficient while Common Loon is Not Evaluated.

Taxonomic Classification

Rank	Central Andes Oldfield Mouse	Common Loon
Kingdom same	Animalia (Animals)	Animalia (Animals)
Phylum same	Chordata (Chordates)	Chordata (Chordates)
Class	Mammalia (Mammals)	Aves (Birds)
Order	Rodentia (Rodents)	Gaviiformes (Gaviiformes)
Family	Cricetidae	Gaviidae
Genus	Thomasomys	Gavia
Species	Thomasomys contradictus	Gavia immer

Evolutionary Relationship

Central Andes Oldfield Mouse and Common Loon share a common ancestor at the Phylum level: Chordata. (Chordates)

Conservation Status

Central Andes Oldfield Mouse

DD — Data Deficient

Common Loon

NE — Not Evaluated

Physical Characteristics

Attribute	Central Andes Oldfield Mouse	Common Loon
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Central Andes Oldfield Mouse

Habitat

Typically found in diverse terrestrial and aquatic ecosystems.

Range

Found in Colombia.

Common Loon

Habitat

Typically found in various aerial, terrestrial, and aquatic environments.

Range

Distributed across Belgium, Denmark, Norway, Sweden, and United States.

Central Andes Oldfield Mouse

The Central Andes Oldfield Mouse (Thomasomys contradictus) is a species in the genus Thomasomys. It is currently classified as Data Deficient on the IUCN Red List. Found in Colombia.

Common Loon

<em>Gavia immer</em>, the common loon or great northern diver, is a large aquatic bird in the family Gaviidae, known for its haunting, yodeling calls across northern lakes. It is found in Belgium, Denmark, Norway, Sweden, and the United States, breeding on freshwater lakes in boreal and subarctic regions and wintering along marine coastlines. The common loon is adept in aerial, terrestrial, and aquatic environments, though it is most highly specialized for diving, using its strong feet positioned far back on its body to pursue fish underwater. It typically feeds on fish, supplemented by crustaceans and aquatic invertebrates. Its striking summer plumage features a black-and-white checkered back and a deep black head with a characteristic white necklace pattern. The species has not been evaluated for IUCN conservation status. Common loons require clear, fish-rich lakes for successful breeding and are sensitive to water quality degradation and human disturbance at nesting sites. Their distinctive calls are emblematic of wilderness in North America and Scandinavia.