Identification (biology)
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In biology, identification is understood to be the recognition of an individual living being. It is to be distinguished from the determination , the assignment of a previously unknown individual to a species or higher taxonomic unit. Based on the use of the English language "identification" (is identification ) but also sometimes used interchangeably with "determination".
In biological field research, identification of individual living beings is usually neither common nor necessary. There are exceptions in two areas in particular:
Identification to research behavior
Individuals must be distinguished if there are individual differences in behavior, e.g. B. through individual learning. They are also essential in studies of the social structure of socially living animal species, for example the great apes. It also is important in the study of migration and migration processes , such as migration distances for migratory birds.
Identification to estimate the settlement density
A number of methods for estimating the settlement density or population size of animal species, in particular very mobile and those with a very large radius of action or those with a hidden way of life with little chance of direct observation, are based on catching individuals with a marking (or other type of individual identification) with subsequent Release mixed with the unlabeled individuals of the population. Subsequent recapture (hence mark - recapture) can be used to indirectly estimate the total population size from the proportion of marked individuals to the total number of individuals caught during the second catch. In the simplest case, it is a simple rule of three , in which from three known quantities (number of marked individuals, number of unmarked individuals in the second catch, number of marked individuals in the second catch) the unknown fourth quantity (number of total individuals present in the first catch date) can be easily determined. The method is based on a number of prerequisites: the first catch must not change the probability of recapture, and the markings used must not affect the mortality or behavior of the marked individuals.
Methods of Identifying Individuals
a) Individual drawing samples. Numerous animal species have drawing patterns that are different for each individual. If these drawings were noted when an individual was caught or observed for the first time, usually with photographic evidence, the individual can be recognized when the individual is caught again or during the second observation. This technique is used very often, e.g. B. the whale shark , bottlenose dolphins , humpback whales , but also dragonflies or amphibians.
b) Color markings, plaques, rings. This is the most common methodology. For example, bird ringing is based on this method. However, it is used for a variety of other applications. For example, the individual spread of grasshoppers was investigated using fluorescent color markings, which make it very easy to find them at night (using a UV lamp). Similar studies were carried out with reflective sheeting (retrieval with a flashlight).
c) Individual injuries. Since color markings are often difficult (adhesion, durability), small injuries are sometimes used as an alternative as permanent markings. It is common to identify ground beetles by individually burned hole patterns in the wing covers. In amphibians, the individual amputation of one or more toes ("toe-clipping") enjoyed some popularity as a method of identification, as these are difficult to mark with color. However, this method has often been criticized in recent years.
d) Genetic markers: Since the DNA sequence of an individual (in sexually reproducing species) is also individual, it is in principle possible to use it for identification. Such methods are becoming increasingly important because the underlying techniques are becoming cheaper and increasingly available in routine use. So z. B. DNA sequences obtained from the faeces of wild boars can be used to determine the distribution pattern and frequency of the animals (which are very difficult to catch alive).
e) Pets that have been implanted with a microchip for animal identification can be identified by the veterinarian, for example, and assigned to their owner using the transponder number (see EU pet passport ).
Individual evidence
- ↑ cf. TRE Southwood: Ecological Methods. Chapman & Hall, London etc., 2nd ed. 1978. ISBN 0-412-30710-3 . Chap. 3 Absolute population estimates using marking techniques. p.70ff.
- ↑ Michael Groß: Astronomy helps identify whale sharks. Biology in Our Time 36 (1): 10.
- ↑ Photo identification. ( Memento of the original from November 5, 2013 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. Dolphin Watch Alliance website .
- ^ Burns, D., P. Harrison and P. Baverstock 2004. "Photographic identification of individual humpback whales ( Megaptera novaeangliae ) on their southern migration past Ballina, NSW, with comparisons to other humpback whale databases from eastern Australia". PDF file ( Memento of the original from May 20, 2011 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice.
- ↑ Beat Schneider & Hansruedi Wildermuth (2009): Dragonflies as individuals - for example Aeshna cyanea (Odonata: Aeshnidae). Entomo Helvetica 2: 185-199.
- ↑ Robert Jehle: Marking and individual recognition of metamorphosed amphibians, with special consideration of the methodology used in the “Amphibian project Donauinsel (Vienna)”. In: Stapfia. Volume 51, Linz, pp. 103-118, PDF on ZOBODAT
- ↑ Narisu, Jeffrey A. Lockwood & Scott P. Schell (1999): A Novel Mark-Recapture Technique and Its Application to Monitoring the Direction and Distance of Local Movements of Rangeland Grasshoppers (Orthoptera: Acrididae) in the Context of Pest Management. Journal of Applied Ecology Vol. 36, No. 4: 604-617.
- ↑ an overview: Phillott, Andrea D., Skerratt, Lee F., McDonald, Keith R., Lemckert, Frank L., Hines, Harry B., Clarke, John M., Alford, Ross A., Speare, Rick ( 2007): Toe-clipping as an acceptable method of identifying individual anurans in mark recapture studies. Herpetological Review, 38 (3): 305-308.
- ↑ Karolina Kolodziej (2012): Development of a method for population estimation of wild boars (Sus scrofa) by means of genotyping of non-invasive samples. Diss., University of Koblenz-Landau full text