Scientists aim to describe a single 'tree of life' that reflects the evolutionary relationships of living things. However, evolutionary relationships are a matter of ongoing discovery, and there are different opinions about how living things should be grouped and named. EOL reflects these differences by supporting several different scientific 'classifications'. Some species have been named more than once. Such duplicates are listed under synonyms. EOL also provides support for common names which may vary across regions as well as languages.

Preferred marks the preferred classification for this taxon.

Recognized By Rank Classification
Species 2000 & ITIS Catalogue of Life: April 2013
view in classification
Life History Characteristics of Placental Non-Volant Mammals Species
  • Halichoerus grypus
Anage Data
Animal Diversity Web Descriptions
AquaMaps Resource
Arctic mammals
BHL: BioDivLibrary's photostream
BOLDS images II Species
BOLDS resource for species-level taxa
Biome & Ecoregion Resource Species
  • Halichoerus grypus
DiscoverLife ID keys resource
  • Halichoerus grypus
DiscoverLife map resource
  • Halichoerus grypus
Dutch Marine and Coastal Species Encyclopedia
  • Halichoerus grypus
EOL Group on Flickr
  • Halichoerus grypus
EOL Group on Flickr
Freshwater and Marine Image Bank, University Libraries, U Washington
GBIF Elevation Data Species
Genome 10K Project Vertebrates
  • Halichoerus grypus
Global Biotic Interactions Species
IUCN Red List
IUCN Red List
view in classification Import
Integrated Taxonomic Information System (ITIS)
view in classification
Inventaire National du Patrimoine Naturel Species
AnAge database
Life History Characteristics of Placental Non-Volant Mammals-to be deleted- Species
Macroecological database of mammalian body mass Species
  • Halichoerus grypus
Macroecological database of mammalian body mass-to be deleted- Species
Mammal life history
Mammals Resource
MarLIN resource
Milk Chemical Data Species
NCBI Taxonomy
view in classification
Natural History Museum Species of the day
NatureServe resource Species
North American Mammals Resource
OBIS Environmental Information
  • Halichoerus grypus (Fabricius, 1791)
OBIS depth range resource
Paleobiology Database
view in classification
Marie Studer
  • Halichoerus grypus
Seacoast Science Center All Taxa List
  • Halichoerus grypus
Sloan-CoML NameLink Project
  • Halichoerus grypus
Social systems of mammalian species-to be deleted- Species
Social systems of mammals Species
  • Halichoerus grypus
Monthly ARKive text import
IUCN Structured Data outlinks
Wikimedia Commons
iNaturalist Images Species
iSpot links Species


EOL content is automatically assembled from many different content providers. As a result, from time to time you may find pages on EOL that are confusing.

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