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All of the following terms appear in the videos or article for this tutorial on biodiversity analyses and unknowns. The terms are arranged here in alphabetical order, and nouns are given in just their singular form unless the plural of the term is unusual.

bestiaries: illustrations made in the middle ages of various animals, birds and even rocks and fantasy creatures that included natural history information and usually a moral lesson

binomial nomenclature: a system of naming each type of organism, consisting of the two-part scientific name that is unique for each species; the first word identifies the genus of the organism and the second word signifies the species; taken together, both words constitute the name of the species; they are written in italics, and only the genus name is capitalized; sometimes also called the Latin name, Latin binomial, or species name

biodiversity: the variety of life on Earth or some specified geographic area of the planet; the diversity of life occurs at the genetic level, at the species level, at the ecosystem level, and in evolutionary lineages

catalog number: a unique identifying number, or mixture of letters and numbers,  assigned to a specimen or a container of specimens in a natural history collection; it not only refers to the specimen itself, but is also tied to all of the metadata about the specimen as well

citizen science: a form of public participation in scientific research in which members of the public help collect and analyze data to help scientists answer research questions; a citizen scientist is a person who participates in a citizen science project

classification: in general, a method of organizing or categorizing a group of things; scientific classification or taxonomy categorizes organisms into groups such as phylum, genus, or species based on their evolutionary relationships

data: information; note that data is a plural word; if you have just one piece of information, it is a datum (singular)

DNA: deoxyribonucleic acid, a molecule that encodes the genetic instructions of organisms; the molecule has a double helix shape and consists of simpler units called nucleotides

environment: an area or habitat; includes living and non-living components

essentialism: a theory, developed by the philosopher Plato, that species and forms in nature were less-than-perfect expressions of some ideal form

expedition: a journey or voyage undertaken for a specific purpose; much of our knowledge about Earth’s biodiversity is the result of biological expedtions

evolutionary: related to evolution, the changes in heritable traits of a population over time

genetic sequencing: the process of determining the precise order of nucleotides in a DNA molecule or DNA fragment

georeferencing: using a geographic information system to record latitude and longitude coordinates to document the exact location at which a specimen was found

holotype: the single physical specimen that is used to formally represent a species and upon which the species name is based

metadata: information associated with something; in taxonomy, it provides a variety of information about a particular specimen, including how, when and by whom a particular set of data was collected, associated photos, molecular analysis, etc.

model: a representation of an object, system, process or abstract concept

molecular techniques: methods used in the manipulation and analysis of DNA

morphology: the study of the form or structure of organisms; gross morphology refers to what can be seen with the naked eye, without the use of microscopes

paratype: a specimen designated, along with the holotype, by the discoverer of a new species; paratypes help expand the description of the new species and can document some of the individual variation, life stages, gender differences, etc. of the new species

phylogenetic history: the genealogy or evolutionary history of a group of organisms

phylum: a taxonomic rank between kingdom and class

plankton: microscopic organisms that live in the ocean and other bodies of water; phytoplankton are plant-like and can photosynthesize; zooplankton are animal-like and cannot photosynthesize

scanning electron microscope: a type of microscope that uses an electron beam to scan a specimen and produce an image that is magnified hundreds of thousands of times which is hundreds of times more than is possible with a regular light microscope

species: a distinct type of organism

species richness: the number of different species in a given geographic area

systematics: the study of the diversity of life, both past and present, and the evolutionary relationships among organisms through time; closely related to, but not synonymous with taxonomy

systematist: a scientist who studies systematics

taxonomist: a scientist who studies taxonomy

taxonomy: the science of naming organisms and defining groups of organisms based on shared physical and molecular characteristics; closely related to, but not synonymous with systematics