Taxonomical Aids

Category: Education

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botanical garden ,herbarium,Taxonomic Keys,Museums,Zoological parks


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Taxonomical Aids Taxonomical aids are defined as the collection of the prime sources of various species of plants, animals and other organisms, which help in their classification, identification and study of the bio-resources. Biologists worldwide have established certain procedures and techniques that help in collecting and storing the data of specimens of the organisms. :

Taxonomical Aids Taxonomical aids are defined as the collection of the prime sources of various species of plants, animals and other organisms, which help in their classification, identification and study of the bio-resources. Biologists worldwide have established certain procedures and techniques that help in collecting and storing the data of specimens of the organisms.

Herbarium :

Herbarium In botany, a herbarium (plural: herbaria) – sometimes known by the Anglicized term herbar – is a collection of preserved plant specimens. These specimens may be whole plants or plant parts: these will usually be in a dried form, mounted on a sheet, but depending upon the material may also be kept in alcohol or other preservative. The same term is often used in mycology to describe an equivalent collection of preserved fungi, otherwise known as a fungarium .

Herbarium :

Herbarium Herbarium specimens Preparing a plant for mounting

Specimen preservation :

Specimen preservation To preserve their form and color, plants collected in the field are spread flat on sheets of newsprint and dried, usually in a plant press, between blotters or absorbent paper. The specimens, which are then mounted on sheets of stiff white paper, are labeled with all essential data, such as date and place found, description of the plant, altitude, and special habitat conditions. The sheet is then placed in a protective case. As a precaution against insect attack, the pressed plant is frozen or poisoned and the case disinfected. Certain groups of plants are soft, bulky, or otherwise not amenable to drying and mounting on sheets. For these plants, other methods of preparation and storage may be used. For example, conifer cones and palm fronds may be stored in labeled boxes. Representative flowers or fruits may be pickled in formaldehyde to preserve their three-dimensional structure. Small specimens, such as mosses and lichens, are often air-dried and packaged in small paper envelopes. No matter the method of preservation, detailed information on where and when the plant was collected, habitat, color (since it may fade over time), and the name of collector is usually included.

Collections management :

Collections management Most herbaria utilize a standard system of organizing their specimens into herbarium cases. Specimen sheets are stacked in groups by the species to which they belong and placed into a large lightweight folder that is labelled on the bottom edge. Groups of species folders are then placed together into larger, heavier folders by genus. The genus folders are then sorted by taxonomic family according to the standard system selected for use by the herbarium and placed into pigeonholes in herbarium cabinets. Locating a specimen filed in the herbarium requires knowing the nomenclature and classification used by the herbarium. It also requires familiarity with possible name changes that have occurred since the specimen was collected, since the specimen may be filed under an older name. Modern herbaria often maintain electronic databases of their collections. Many herbaria have initiatives to digitize specimens to produce a virtual herbarium. These records and images are made publicly accessible via the Internet when possible.

Uses :

Uses Herbaria are essential for the study of plant taxonomy, the study of geographic distributions, and the stabilizing of nomenclature. Thus it is desirable to include in a specimen as much of the plant as possible (e.g., flowers, stems, leaves, seed, and fruit). Linnaeus' herbarium now belongs to the Linnean Society in England. Specimens housed in herbaria may be used to catalogue or identify the flora of an area. A large collection from a single area is used in writing a field guide or manual to aid in the identification of plants that grow there. With more specimens available, the author of the guide will better understand the variability of form in the plants and the natural distribution over which the plants grow. Herbaria also preserve a historical record of change in vegetation over time. In some cases, plants become extinct in one area, or may become extinct altogether. In such cases, specimens preserved in an herbarium can represent the only record of the plant's original distribution. Environmental scientists make use of such data to track changes in climate and human impact. Many kinds of scientists use herbaria to preserve voucher specimens; representative samples of plants used in a particular study to demonstrate precisely the source of their data.

Botanical garden :

B otanical garden A botanical garden is a controlled and staffed institution for the maintenance of a living collection of plants under scientific management for purposes of education and research, together with such libraries, herbaria, laboratories, and museums as are essential to its particular undertakings. Each botanical garden naturally develops its own special fields of interests depending on its personnel, location, extent, available funds, and the terms of its charter. It may include greenhouses, test grounds, a herbarium, an arboretum, and other departments. It maintains a scientific as well as a plant-growing staff, and publication is one of its major modes of expression.

Royal Botanic Gardens, Kew, London, established 1759:

Royal Botanic Gardens, Kew , London, established 1759

A contemporary botanic garden:

A contemporary botanic garden A contemporary botanic garden is a strictly protected natural urban green area where a managing organization creates landscaped gardens and holds documented collections of living plants and/or preserved plant accessions containing functional units of heredity of actual or potential value for purposes such as scientific research, education, public display, conservation, sustainable use, tourism and recreational activities, production of marketable plant-based products and services for improvement of human well-being.

Braunschweig Botanical Garden, Germany :

Braunschweig Botanical Garden, Germany

Beginnings of botanical science :

Beginnings of botanical science During the 16th and 17th centuries the first plants were being imported to these major Western European gardens from Eastern Europe and nearby Asia (which provided many bulbs) and these found a place in the new gardens where they could be conveniently studied by the plant experts of the day. For example, Asian introductions were described by Carolus Clusius (1526–1609) who was director, in turn, of the Botanical Garden of the University of Vienna and Hortus Botanicus Leiden. Many plants were being collected from the Near East, especially bulbous plants from Turkey. Clusius laid the foundations of Dutch tulip breeding and the bulb industry, and he helped create one of the earliest formal botanical gardens of Europe at Leyden where his detailed planting lists have made it possible to recreate this garden near its original site. "The hortus medicus of Leyden in 1601 was a perfect square divided into quarters for the four continents, but by 1720 however it was a rambling system of beds, struggling to contain the novelties rushing in" and it became better known as the hortus academicus . His Exoticorum libri decem (1605) is an important survey of exotic plants and animals that is still consulted today. The inclusion of new plant introductions in botanic gardens meant that their scientific role was now widening as botany gradually asserted its independence from medicine.

The Hanging Gardens of Babylon with the Tower of Babel in the background, a 16th-century hand-coloured engraving by Martin Heemskerck. :

The Hanging Gardens of Babylon with the Tower of Babel in the background, a 16th-century hand- coloured engraving by Martin Heemskerck .

Role and functions :

Role and functions Many of the functions of botanical gardens have already been discussed in the sections above, which emphasize the scientific underpinning of botanical gardens with their focus on research, education and conservation. However, as multifaceted organizations all sites have their own special interests. In a remarkable paper on the role of botanical gardens Ferdinand Mueller (1825–1896), the director of the Royal Botanic Gardens, Melbourne (1852–1873), stated that "in all cases the objects [of a botanical garden] must be mainly scientific and predominantly instructive". He then detailed many of the objectives that were being pursued by the world's botanical gardens in the middle of the 19th century, when European gardens were at their height. Many of these are listed below to give a sense of the scope of botanical gardens' activities at that time, and the ways in which they differed from parks or what he called "public pleasure gardens".

Future :

Future Botanical gardens are still being built, such as the first botanical garden in Oman, which will be one of the largest gardens in the world. Once it is completed and will house the first large-scale cloud forest in a huge glasshouse. There has been a remarkable development of botanical gardens in China over recent years including the Hainan Botanical Garden of Tropical Economic Plants South China Botanical Garden at Guangzhou, the Xishuangbanna Botanical Garden of Tropical Plants and the Xiamen Botanic Garden but in developed countries many have closed for lack of financial support, this being especially true of botanical gardens attached to universities. In recent times the focus has been on creating an awareness of the threat to ecosystems from human overpopulation and its consequent need for biological and physical resources. Botanical gardens provide an excellent medium for communication between the world of botanical science and the general public. Education programs can help the public develop greater environmental awareness by understanding the meaning and importance of ideas like conservation and sustainability.

The Eden Project established in 2000 in Cornwall, England includes a modern botanical garden exploring the theme of sustainability :

The Eden Project established in 2000 in Cornwall, England includes a modern botanical garden exploring the theme of sustainability


Museums Biological museums are collections of plant and animal specimens preserved for study and reference. In museums, specimens are preserved in containers and jars containing preservatory chemical solutions. Insects are preserved in insect boxes, where as larger animals like birds and mammals are usually stuffed and preserved. Museums also contain skeletons and fossils of animals.

Biological museums:

Biological museums

Zoological parks:

Zoological parks Zoological parks are places where animals are kept in a protective environment and looked after from other stress like predators etc. In zoological parks, all animals are provided with an environment similar to their natural habitat.

 Indira Gandhi Zoological Park:

Indira Gandhi Zoological Park

Nehru Zoological Park:

Nehru Zoological Park

Taxonomic Keys:

Taxonomic Keys A taxonomic key is a device used by biologists for identifying unknown organisms. Keys are constructed so that the user is presented with a series of choices about the characteristics of the unknown organisms; by making the correct choice at each step of the key, the user is ultimately led to the identity of a specimen. Keys that are based on successive choices between only two statements are known as dichotomous keys and are the type of key preferred by most biologists. Such keys are constructed using contrasting characteristics to divide the organisms in the key into smaller and smaller groups; each time a choice is made, a number of organisms are eliminated. If sufficient characteristics are contrasted, the number of possibilities for the identity of the unknown organism is eventually reduced to one.

Using a Taxonomic Key:

Using a Taxonomic Key Examining a specimen carefully and noting its characteristics before beginning to key it out are good habits to develop when trying to identify plants. Listed below are some other helpful hints for the successful use of taxonomic keys: Read any introductory comments concerning the format of the key, abbreviations, and so forth, before using the key. Always read both choices presented at each step of the key. Use a glossary to find the definition of any terms you do not understand. Use a ruler when measurements are required; do not guess. Because living organisms are always somewhat variable, do not make a decision based on a single specimen; instead, arrive at an average by examing several different specimens. The key presented in your lab manual can be used for identifying several dozen of the most commonly encountered trees, shrubs and vines of the SWT campus. You can practice using the key on plants found in your own yard or neighborhood.

Taxonomic Keys:

Taxonomic Keys

Advantages and disadvantages :

Advantages and disadvantages A large amount of knowledge about reliable and efficient identification procedures may be incorporated in good single-access keys. Characteristics that are reliable and convenient to observe most of the time and for most species (or taxa ), and which further provide a well-balanced key (the leads splitting number of species evenly) will be preferred at the start of the key. However, in practice it is difficult to achieve this goal for all taxa in all conditions. If the information for a given identification step is not available, several potential leads must be followed and identification becomes increasingly difficult. Although software exists that helps in skipping questions in a single-access key, the more general solution to this problem is the construction and use of multi-access keys, allowing a free choice of identification steps and are easily adaptable to different taxa (e.g., very small or very large) as well as different circumstances of identification (e. g., in the field or laboratory).

Taxonomical key of beetles:

Taxonomical key of beetles

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