Species
Definition
In biology, a species is the fundamental unit of classification, generally defined as a group of organisms capable of interbreeding and producing fertile offspring. The number of recognised penguin species has changed over time as genetic techniques refine our understanding. The current widely cited field-guide count is about 18 species, though some authorities recognise 17 or 19 depending on whether the rockhopper complex is split into two or three species. Penguin Place follows the three-way rockhopper split and therefore publishes 19 species profiles. Species-level decisions matter for conservation because splitting one species into two can mean each new species has a smaller population and may qualify for a higher threat category.
Related Terms
Spheniscidae is the biological family that contains all living penguin species.
The IUCN Red List of Threatened Species is the world's most comprehensive inventory of the conservation status of plant and animal species, maintained by the International Union for Conservation of Nature.
Frequently Asked Questions
What does species mean in penguin biology?
In biology, a species is the fundamental unit of classification, generally defined as a group of organisms capable of interbreeding and producing fertile offspring. The number of recognised penguin species has changed over time as genetic techniques refine our understanding. The current widely cited field-guide count is about 18 species, though some authorities recognise 17 or 19 depending on whether the rockhopper complex is split into two or three species. Penguin Place follows the three-way rockhopper split and therefore publishes 19 species profiles. Species-level decisions matter for conservation because splitting one species into two can mean each new species has a smaller population and may qualify for a higher threat category.
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Glossary entries define the language. FAQ answers common questions; guides carry the longer Survival Lab arguments.
More in taxonomyWhere this definition comes from
Reference bodies behind the taxonomy terminology. Links last checked August 5, 2026.
- IUCN Red List - Global conservation assessments and extinction-risk categories.
- BirdLife Data Zone - Species accounts, distribution, and population summaries.
- Australian Museum - Little penguin biology and coastal breeding behavior.