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  • Emperor penguins by Glenn Grant, National Science Foundation, Public Domain
  • Fungi by Arthur Chapman , 
  • Adansonia grandidieri by Rita Willaert, cc by-nc
  • Sea Turtle by Brocken Inaglory, cc by-sa


Animal: A member of the kingdom Animalia. A multicellular eukaryote that undergoes tissue-layer development and obtains its food by ingestion. (1)


Binomial name: The two-part Latin name assigned to a species under the system of binomial nomenclature established in the 1700s by Swedish botanist Carl Linnaeus Species.The first name is the name of the genus the species belongs to, the second name is the species name. For example: Anolis carolinensis. (3)  

BioBlitz: An event in which teams of scientists, volunteers, and community members join together to find, identify, and learn about as many local plant and animal species as possible in a set amount of time (often 24 hours). (4) 

Biodiversity: The variety of all living things (species), including plants, animals, microorganisms; their interrelationships; the genes they contain; and, the ecosystems they form. 


Citizen science: Activities in which volunteers, such as students, the general public and enthusiasts partner with scientists to collect information and answer real-world questions.

Classification: Taxonomic classification refers to the organization of organisms by traits, such as size, color, or form, or by their degree of genetic relatedness.  Most scientists have agreed on a scheme that classifies all life on Earth into three Domains; each Domain is further divided into Kingdoms, Phyla, Classes, Orders, Families, Genera, and Species. 

Collections: The EOL Collections feature allows you to organize content (species information, images, video, sound, maps, etc.) on EOL for your purposes. You can organize, annotate and share your collection with others.

Common name:  Any of (often several) nonscientific names for a species used in everyday speech by nonscientists, such as domestic dog for Canis familiaris

Cryptic:  Having markings, coloration, shapes, or other features that cause an animal to be camouflaged in its natural environment; being difficult to see or otherwise detect. (3)

Curator:  An EOL member, usually a scientist by training, responsible for quality control of the information or content (these are known as data objects) on an EOL species page.


Data Object: One of several types of content on a species page in the form of a text block (such as a species description), map, image, or other media that is imported from an EOL content provider or added directly by an EOL member. Data objects combined together under a scientific name make up an EOL taxon page.

Domain: A taxonomic classification category above Kingdom.  The three domains are Archaea, Bacteria and Eukaryota. (See Classification).


Ecology: The study of the interrelationships among plants, animals and other organisms and their interaction with all aspects of their natural environment. (3)

Ecosystem: A community of plants, animals and microorganisms that are linked by energy and nutrient flows and that interact with each other and with the physical environment. Rainforests, deserts, coral reefs, grasslands and rotting saguaro cactus are all examples of ecosystems. (1)

Endangered species: Species which are threatened with immediate extinction or extirpation if the factors which are threatening them continue to operate. Included are species whose numbers have been reduced to a critical level or whose habitats have been so drastically reduced that they are deemed to be in immediate danger of extinction. (2)

Endemic species: Native to, and naturally restricted to, one specific region. (1)

Evolution: The change in the inherited traits (both genetic and phenotypic, or observable) of biological populations over successive generations. 

Evolutionary tree: A branching diagram, also known as a phylogenetic tree, is that shows the evolutionary relationships (or ancestry) between species or higher taxa based on available evidence.


Fauna: The animals found in a given area. (1)

Flora: The plants found in a given area. (1)


Gene: A section of a chromosome containing enough DNA to control the formation of one protein; a gene controls the transmission of a hereditary character. (1)

Gene pool: The total number of genes (or alleles) in a population of organisms. (1)


Habitat: The place or environment where a plant or animal naturally lives and grows; a group of particular environmental conditions. (1)


Indicator species: A species whose presence or absence is known to be indicative of a particular habitat or environmental condition. (1)

Indigenous species: A species that occurs naturally in an area or habitat.  A species that originated in, and grows or lives naturally in a particular region or environment. (= native). (1)

Introduced species: A species that has been transported by humans across a geographic barrier to a location where it previously did not exist. (= exotic, non-native, alien.)  Introduced species can compete with and cause problems for native species, i.e. become invasive exotic species. (1)

Invasive species: An aggressive alien species that displaces native species; most commonly in disturbed habitats, although the most destructive invasive species also displace natives in intact communities. (1)

Invertebrates: Animals lacking backbones (i.e., vertebral columns). (1)


Keystone species: A species that exerts a major influence on the composition and dynamics of the community in which it lives; species which influence many other taxa by their presence. (1)


Life cycle: The span of the life of an organism, from the moment of fertilization (or asexual generation) to the time it reproduces. (1)


Mammal: Any animal of the class Mammalia, characterized (in part) by the production of milk by the female mammary glands and the possession of hair for body covering. (1)

Micro-organisms: Any organism that can be seen only with the aid of a microscope. (2)

Migration: The movement of animals in response to seasonal changes or changes in the food supply. Examples of animals that migrate include ruby-throated hummingbirds, salmon, monarch butterflies and elephants. (1)

Model organism: A model organism is a non-human species that is widely studied and used to understand particular biological functions or systems.


Natural selection: The natural process by which biological traits that affect survival and/or reproduction become more or less common in a population.


Omnivore: An animal that mainly eats all kinds of things, including plants and animals. (3)

Organism: A living thing (plant, animal, or microbe). (3)


Plants: A member of the kingdom Plantae. Characterized by being multicellular, having cells specialized as distinct tissues, and gaining its nutrition by photosynthesis. (1)

Population: Any group of organisms, belonging to the same species, coexisting at the same time and in the same place and capable of interbreeding with one another. (1)


Range: The geographical area over which an animal is distributed.of things, including plants and animal. (3)

Reproduction: The process of producing offspring. (3)


Speciation: Evolution of reproductive isolation within population (or group of populations), resulting in two or more descendant species. (1)

Species: A group of individuals that naturally (or potentially) interbreed in the wild to produce fertile offspring and their own evolutionary trajectory separate from other species.  Species are typically recognizable by their possession of a unique set of characteristics that distinguishes them from other species.  Species have a birth (speciation), life (anagenesis), and death (extinction). (1)

Synonym: In taxonomy, different names used for the same species (or other taxon).  In such cases, one or more are deemed invalid because another valid name previously existed for the taxon (and thus has priority).  The “senior synonym” has priority over the “junior synonym.” (1)


Taxon:  plural: taxa  (1) Any group or rank in a biological classification into which related organisms are classified.; or (2) A taxonomic unit in the biological system of classification of organisms, for example: a phylum, order, family, genus, or species. (4) 

Taxon page: A single webpage of the Encyclopedia of Life, presenting peer-reviewed information about a taxa or taxon in a standard format.  Content (i.e., images, text) submitted by other EOL members will also appear on a species page, but will appear as "unreviewed" until an EOL curator has marked it as “trusted”.

Taxonomy: The science of naming and classifying organisms. (1)


  1. Brusca, R. C., W. Moore and S. Shuster.  Invertebrates, 3ed.  Sinauer Associates. (In preparation).
  2. Encyclopedia of Earth. Environmental Information Coalition, National Council for Science and the Environment, Boston University. CC BY-SA
  3. Animal Diversity Web. Regents of the University of Michigan, University of Michigan Museum of Zoology.
  4. Biology Online. Accessed 8/19/13