Taxonomic Aids: Procedure of Herbarium Preparation, Its Uses and Museum

With this vast array of living beings present on earth, it is essential to be able to identify each of them. Taxonomy is the field of science that deals with the grouping or classification of organisms.  Identification, characterization and nomenclature are crucial steps of taxonomy. Each step plays a major role in keeping track of the abundant number of species that mother Earth harbours. This has simplified the intricacy of naming and grouping the organisms. 

Did you know that 391,000 species of vascular plants are currently known, of which about 369,000 species are flowering plants as per the Royal Botanical Gardens, Kolkata? Have you ever wondered what is the process behind it? What are the magic hands that make this complex process possible? Well, in order to extract the right information about each and every species identified, the specimen used for study plays an important role. Collection, proper preservation and storage of specimens plays an important role in taxonomic studies. Let’s study how the specimens are collected, preserved and studied.

Table of Contents

• Taxonomic aids
• Common taxonomic aids
• Herbarium
• Museum
• Practice problems
• FAQs

Taxonomic Aids

Taxonomic aids are the techniques, procedures and information stored that are used in identification and classification of various organisms. It comprises collections of samples or preserved creatures that aid in thorough investigation for taxonomic hierarchy identification.

Common Taxonomic Aids

Taxonomic aids help in the identification of species and their classification. Common taxonomic aids include the herbarium, museum, botanical gardens, zoological parks, keys, monographs, manuals, flora, catalogues, and publications. Taxonomic aids can be of two types:

Dead

The specimens stored are not alive. This includes herbarium (plants) and museum (animals).

Living

The specimens stored are alive. This includes botanical gardens (plants) and zoological parks (animals). 

Let’s study about the herbarium and museum in detail.

Herbarium

Introduction

Herbarium is a place with a collection of dried, pressed and preserved plant species which are mounted on sheets. 

The sheets are arranged as per the universally accepted system of classification. The herbarium sheets have all the necessary information like date and place of specimen collection, scientific name, local name, collector’s name, family name etc. 

Herbarium serves as a quick referral system in taxonomic studies and a repository for future reference.

GIF: Herbarium

Equipments used to set up Herbarium

The equipments used to set up herbarium are: digger and pruning knife, vasculum, sickle with long handle, polythene bags, blotting papers, magazines or newspapers, field notebook, field visit and specimen collection, glue, herbarium sheets and labels.

Procedure of Herbarium Preparation

Field visit and specimen collection

This step involves selection of areas for botanical excursion. It is preferred to visit the same site in different seasons. Entire plant is selected for herbaceous plant. For other plants, shoots that have important parts of a plant are cut using a pruning knife. 5 - 6 specimens are collected. The collected specimens are assigned with field numbers.

Pressing and Drying

This step involves spreading the collected specimen over newspaper sheets or magazines. The papers are changed at regular intervals to prevent fungal growth. The sheets are dried in a press or manually.

GIF: Pressing and drying

Mounting

This step involves selection of herbarium sheets, followed by placing dried samples on the sheet with the help of glue. The plant parts like seeds and fruits are placed in packets attached to the sheet. The sample is further covered with polythene in order to prevent damage to fragile parts. They are sprayed with fungicides. 

GIF: Mounting

Labelling

Labelling is done parallely with mounting. Herbarium sheet is labelled with the information such as family name, genus name, species name, characteristics, area of specimen collection, date of specimen collection, collector’s name.

Storage

Specimens collected are preserved and stored. They are normally stored in metallic cup boards. The storage place is disinfected to control insects and other pests. 

Uses of Herbarium

Herbarium is a repository of specimens of plants. The use of herbarium makes authentic identification possible. It gives information about flora available, quick referral for taxonomic studies, and knowledge of the ecology of different places. 

Few Important Herbaria

Museum

Introduction

Museum is a place with the collection of preserved specimens of plants and animals which are used for study and reference. It is generally set up and found at educational institutions. It preserves specimens and records information for taxonomic purposes.

Method of Storing Different Specimens

Specimens are normally stored in a container or jar filled with preservative solutions. They are correctly identified and labelled before storage. 

Insects

They are preserved in insect boxes after collection, preservation and pinning. 

Birds and mammals 

Stuffed specimens - They are usually stuffed and preserved after collection.

Skeletons can be preserved. Examples include skeletons of dinosaurs.

Roles of Museum

Museums are used for research, educational purposes, exhibitions, preservation of the lost organisms and for proper recordings and classifications.

Names of Famous Museums

Some of the famous museums are: 

• Rock Creek Nature Centre, Washington, United States National Museum, Washington
• Zoology Museum, Amsterdam, Neth
• National Museum of Anthropology, Mexico City
• Field Museum of Natural History, Chicago
• Natural History Museum, London.

Practice Problems of Taxonomic Aids

Question1. Which of the following taxonomic aids deals with dead organisms?

A. Botanical gardens
B. Herbaria
C. Zoos
D. Both b and c.

Answer: In botanical gardens and zoos, the specimens present are dead whereas in botanical and zoological gardens the specimens kept are alive. Hence, option b is correct.

Question2. Match the following with respect to the procedure of herbarium preparation.

A. A-I, B-III, C-II, D-IV, E-V
B. A-II, B-III, C-II, D-IV, E-V
C. A-II, B-I, C-IV, D-V, E-III
D. A-I, B-V, C-III, D-IV, E-II

Answer: The steps of preparation of herbarium include field visit and specimen collection, pressing and drying, mounting, labelling, and storage. In field visit and specimen collection,a site is selected to be visited and complete specimens or portions of some specimens are collected. Field numbers are assigned to the collected specimens. In pressing and drying, the collected specimen was pressed over newspaper sheets or magazines. The sheets are further dried in a press.

Mounting entails selecting herbarium sheets and attaching dried samples to the sheet with the help of glue. To keep the specimens safe, they are sprayed with fungicides. Herbarium sheets are labelled with information such as family name, genus name, species name, characteristics, specimen collecting area, specimen collection date, and collector's name during the labelling process. The specimens are often stored in metallic cup boards. To keep flies and other pests at bay, the storage area is disinfected. Hence, c is the correct option.

Question3. What are taxonomic aids?

Answer: Taxonomic aids include the techniques, procedures, and information stored which are employed in the identification and classification of diverse organisms. It is made up of collections of samples or preserved species that aid in the identification of taxonomic hierarchy. The herbarium, museum, botanical gardens, zoological parks, keys, monographs, manuals, flora, catalogues, and publications are all common taxonomic aids.

Question4. State the importance of museums.

Answer: Extinct and dead organisms are preserved in museums. They also keep track of the data of these organisms. As a result, they assist researchers and taxonomists in learning more about different organisms and determining their place in the taxonomic hierarchy. It also aids in the study of evolutionary relationships among distinct creatures.

FAQs of Taxonomic Aids

Question1. Name the largest herbarium in the world.

Answer: The Royal Botanical Garden at Kew, England, houses the world's biggest herbarium. It is a World Heritage Site which houses 6.5 million plant species.

Question2. What is the importance of the labelling process in herbarium? 

Answer: Each specimen has a label with vital information regarding its identity, as well as where, when, and by whom it was gathered or collected. The herbarium is similar to a library of preserved plants, with specimens and labels containing all of the information. The scientific names (in Latin), collector's name, collection location, and date are all written on the herbarium sheet.

Question3. How are insects preserved in museums?

Answer: Dry specimens of plants and animals are sometimes preserved. After capturing, killing, and pinning insects, they are kept in insect boxes.

Question4. Where was the first herbarium set?

Answer: Herbarium was first set up at Pisa in Italy.