A zoological specimen is an animal or part of an animal preserved for scientific use. Various uses are: to verify the identity of a (

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

), to allow study, increase public knowledge of

zoology Zoology ( , ) is the scientific study of animals. Its studies include the anatomy, structure, embryology, Biological classification, classification, Ethology, habits, and distribution of all animals, both living and extinction, extinct, and ...

. Zoological specimens are extremely diverse. Examples are bird and mammal study skins, mounted specimens, skeletal material, casts, pinned insects, dried material, animals preserved in liquid preservatives, and microscope slides.

Natural history museums A natural history museum or museum of natural history is a scientific institution with natural history collections that include current and historical records of animals, plants, fungi, ecosystems, geology, paleontology, climatology, and more ...

are repositories of zoological specimens

Study skins

Bird and mammal specimens are conserved as dry study skins, a form of taxidermy. The skin is removed from the animal's carcass, treated with absorbents, and filled with cotton or polyester batting (In the past plant fibres or sawdust were used). Bird specimens have a long, thin, wooden dowel wrapped in batting at their center. The dowel is often intentionally longer than the bird's body and exits at the animal's vent. This exposed dowel provides a place to handle the bird without disturbing the feathers. Mammal study skins do not normally utilize wooden dowels, instead preparators use wire to support the legs and tail of mammals. Labels are attached to a leg of the specimen with thread or string. Heat and chemicals are sometimes used to aid the drying of study skins.

Skeletal Preparations (Osteology)

Osteological Osteology () is the scientific study of bones, practiced by osteologists . A subdiscipline of anatomy, anthropology, archaeology and paleontology, osteology is the detailed study of the structure of bones, skeletal elements, teeth, microbone morp ...

collections consist of cleaned, complete and partial skeletons, crania of

Vertebrates Vertebrates () are animals with a vertebral column (backbone or spine), and a cranium, or skull. The vertebral column surrounds and protects the spinal cord, while the cranium protects the brain. The vertebrates make up the subphylum Vertebra ...

, mainly birds and mammals. They are used in studies of

comparative anatomy Comparative anatomy is the study of similarities and differences in the anatomy of different species. It is closely related to evolutionary biology and phylogeny (the evolution of species). The science began in the classical era, continuing in t ...

and to identify bones from archaeological sites. Human bones are used in medical and forensic studies.

Molluscs

In museum collections it is common for the dry material to greatly exceed the amount of material that is preserved in alcohol. The shells minus their soft parts are kept in card trays within drawers or in glass tubes, often as lots (a lot is a collection of a single species taken from a single locality on a single occasion). Shell collections sometimes suffer from Byne's disease which also affects birds eggs. The study of dry mollusc shells is called

conchology Conchology, from Ancient Greek κόγχος (''kónkhos''), meaning "cockle (bivalve), cockle", and -logy from λόγος (''lógos''), meaning "study", is the study of mollusc shells. Conchology is one aspect of malacology, the study of mollus ...

as distinct from

malacology Malacology, from Ancient Greek μαλακός (''malakós''), meaning "soft", and λόγος (''lógos''), meaning "study", is the branch of invertebrate zoology that deals with the study of the Mollusca (molluscs or mollusks), the second-largest ...

(wet specimens).

Insects and similar invertebrates

Most hard-bodied insect specimens and some other hard-bodied invertebrates such as certain

Arachnid Arachnids are arthropods in the Class (biology), class Arachnida () of the subphylum Chelicerata. Arachnida includes, among others, spiders, scorpions, ticks, mites, pseudoscorpions, opiliones, harvestmen, Solifugae, camel spiders, Amblypygi, wh ...

a, are preserved as pinned specimens. Either while still fresh, or after rehydrating them if necessary because they had dried out, specimens are transfixed by special stainless steel entomological pins. As the insect dries the internal tissues solidify and, possibly aided to some extent by the integument, they grip the pin and secure the specimen in place on the pin. Very small, delicate specimens may instead be secured by fine steel points driven into slips of card, or glued to card points or similar attachments that in turn are pinned in the same way as entire mounted insects. The pins offer a means of handling the specimens without damage, and they also bear labels for descriptive and reference data. Once dried, the specimens may be kept in conveniently sized open trays. The bottoms of the trays are lined with a material suited to receiving and holding entomological pins securely and conveniently. Cork and foam plastics are convenient examples. However, open trays are very vulnerable to attack by museum beetle and similar pests, so such open trays are stored in turn inside glass-topped, insect-proof drawers, commonly protected by suitable

pesticide Pesticides are substances that are used to control pests. They include herbicides, insecticides, nematicides, fungicides, and many others (see table). The most common of these are herbicides, which account for approximately 50% of all p ...

s or repellents or barriers. Alternatively, some museums store the pinned specimens directly in larger trays or drawers that are glass-topped and stored in cabinets. In contrast to such dried specimens, soft-bodied specimens most commonly are kept in "wet collections", meaning that they are stored in alcohol or similar preservative or fixative liquids, according to the intended function. Small specimens, whether hard or soft bodied, and whether entire, dissected, or

sectioned Involuntary commitment, civil commitment, or involuntary hospitalization/hospitalisation, or informally in Britain sectioning, being sectioned, commitment, or being committed, is a legal process through which an individual who is deemed by a qual ...

, may be stored as

microscope slide A microscope slide is a thin flat piece of glass, typically 75 by 26 mm (3 by 1 inches) and about 1 mm thick, used to hold objects for examination under a microscope. Typically the object is mounted (secured) on the slide, and then ...

preparations.

Wet specimens

"Wet" specimen collections are stored in different solutions. A very old method is to store the specimen in 70%

ethanol Ethanol (also called ethyl alcohol, grain alcohol, drinking alcohol, or simply alcohol) is an organic compound with the chemical formula . It is an Alcohol (chemistry), alcohol, with its formula also written as , or EtOH, where Et is the ps ...

with various additives after fixing with

formalin Formaldehyde ( , ) (systematic name methanal) is an organic compound with the chemical formula and structure , more precisely . The compound is a pungent, colourless gas that polymerises spontaneously into paraformaldehyde. It is stored as ...

or in these days sometimes with a salt-solution. Some methods are very useful, because the color can be preserved. (Salt-)Solutions like this are Jores, Kaiserling and Romhányi. Modern specimens are stored in

borosilicate glass Borosilicate glass is a type of glass with silica and boron trioxide as the main glass-forming constituents. Borosilicate glasses are known for having very low coefficients of thermal expansion (≈3 × 10−6 K−1 at 20 °C), ma ...

due to its chemical and thermal resistance and good optical clarity.

Data

Minimum data associated with zoological specimens is the place and date of collection, attached to the specimen by a label. Additional information is the name of the collector and the habitat. Tissue from specimens may be saved for genetic studies (molecular data,

DNA Deoxyribonucleic acid (; DNA) is a polymer composed of two polynucleotide chains that coil around each other to form a double helix. The polymer carries genetic instructions for the development, functioning, growth and reproduction of al ...

). Depending on the animal group, other data may be included, for instance in bird collections the bird’s breeding condition, weight, colours of its eyes, bills and legs and nature of the stomach contents.

Composite specimens

A single specimen may be a composite of preparations sharing a unique number. An example would be a vertebrate with an alcohol-preserved skin and viscera, a cleared and stained head, the post-cranial dried skeleton,

histological Histology, also known as microscopic anatomy or microanatomy, is the branch of biology that studies the microscopic anatomy of biological tissue (biology), tissues. Histology is the microscopic counterpart to gross anatomy, which looks at large ...

, glass slides of various organs, and frozen tissue samples. This specimen could also be a voucher for a publication, or photographs and audiotape.

Voucher specimens

A voucher is a representative specimen of the animal used in a study, such as a specimen collected as part of an

ecological Ecology () is the natural science of the relationships among living organisms and their environment. Ecology considers organisms at the individual, population, community, ecosystem, and biosphere levels. Ecology overlaps with the closely re ...

survey or a specimen which was the source of DNA for a molecular study. Voucher specimens confirm the identity of the species referred to in the study. They are a backup against misidentification, changing

species concepts A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of classification and a ...

which mislead results.

Type Type may refer to: Science and technology Computing * Typing, producing text via a keyboard, typewriter, etc. * Data type, collection of values used for computations. * File type * TYPE (DOS command), a command to display contents of a file. * ...

specimens are a special type of voucher specimen used in

taxonomy image:Hierarchical clustering diagram.png, 280px, Generalized scheme of taxonomy Taxonomy is a practice and science concerned with classification or categorization. Typically, there are two parts to it: the development of an underlying scheme o ...

Historic specimens

Museum zoological specimens may have historic significance. For example, the specimens collected by

Johann Baptist von Spix Johann Baptist Ritter von Spix (9 February 1781 – 13 March 1826) was a German natural history, biologist. From his expedition to Brazil, he brought to Germany a large variety of specimens of plants, insects, mammals, birds, amphibians and fish. ...

and

Carl Friedrich Philipp von Martius Carl Friedrich Philipp (Karl Friedrich Philipp) von Martius (17 April 1794 – 13 December 1868) was a German botany, botanist and explorer. Between 1817 and 1820, he travelled 10,000 km through Brazil while collecting botanical specimens. His m ...

during their Brazil Expedition (1817–1820) are housed in the Munich Zoology Museum.

Models

Museums make extensive use of models. When these are accurate they are considered to be specimens in their own right. Examples are the glass

invertebrates Invertebrates are animals that neither develop nor retain a vertebral column (commonly known as a ''spine'' or ''backbone''), which evolved from the notochord. It is a paraphyletic grouping including all animals excluding the chordate subphylum ...

Leopold and Rudolf Blaschka Leopold Blaschka (27 May 1822 – 3 July 1895) and his son Rudolf Blaschka (17 June 1857 – 1 May 1939) were glass artists from Dresden, Germany. They were known for their production of biological and botanical models, including glass sea crea ...

Examples

File:Eléphant d'Afrique naturalisé.JPG, Mount of

African elephant African elephants are members of the genus ''Loxodonta'' comprising two living elephant species, the African bush elephant (''L. africana'') and the smaller African forest elephant (''L. cyclotis''). Both are social herbivores with grey skin. ...

and other animals in Paris Museum File:Chitra indica, skeleton.jpg, ''

Chitra indica The Indian narrow-headed softshell turtle (''Chitra indica''), also known as the small-headed softshell turtle or the Indo-Gangetic softshell turtle, is an endangered species of softshell turtle native to waterways and rivers of the Indian subc ...

'' (narrow-headed soft-shelled turtle) skeleton File:Dynastinae.jpg, Pinned insects (

Dynastinae Dynastinae or rhinoceros beetles are a subfamily of the scarabaeidae, scarab beetle family (biology), family (Scarabaeidae). Other common names – some for particular groups of rhinoceros beetles – include Hercules beetles, unicorn be ...

) File:Caixa de preparacións microscópicas (vista frontal).jpg, Microscope slides File:Pseudocrypturus.jpg, Cast of a bird fossil File:Doris Mable Cochran (1898-1968), measuring a turtle shell.jpg, Zoologist measuring a turtle shell File:Acanthopterygii-senkenberg hg.jpg, Acanthopterygii (fish) at

Naturmuseum Senckenberg The Naturmuseum Senckenberg () is a museum of natural history, located in Frankfurt am Main. It is the second-largest of its kind in Germany. In 2010, almost 517,000 people visited the museum, which is owned by the Senckenberg Nature Research S ...

File:Zoological Exhibition - NM Prague 17.JPG, Model of ''

Arenicola marina The blow lugworm (''Arenicola marina''), also known as sandworm, is a large species of marine worm. Its coiled Worm cast, castings are a familiar sight on a beach at low tide but the animal itself is rarely seen except by those who, from curiosit ...

'' in a zoological exhibition at

National Museum (Prague) The National Museum (NM) (Czech language, Czech: ''Národní muzeum'') is a public museum dedicated to natural scientific and historical collections of the Czech Republic, its History of the Czech lands, history, Culture of the Czech Republic, cul ...

File:Technique of diaphanization applied in a fish.jpg, Specimen of fish clarified for visualization of anatomical structures on display at the MAV/USP.

References

External links

Naturkundemuseum StuttgartZoological Collection Database SZN
Impressive. Images of wet specimens,labels,catalogues etc.

The role of voucher specimens in validating faunistic and ecological research
Museum handbook
Bird skin preparation
Texas Tech University
Halter, A.S. Standards for management of the recent mammal and bird collections Texas Tech University
Natural history collections of the University of EdinburghWet Specimen collection of the National Museum of Australia