Lesson 1 of 8 · 7 min

Diversity and the need for naming

NCERT §1.1

Meera's grandmother calls the fruit on the tree 'maanga'. On a video call, her cousin in Hyderabad says 'mamidi' and her friend in Delhi says 'aam'. Three words, one fruit. How would a scientist in Brazil know which plant any of them meant?

The story this chapter follows: Meera's Sunday: garden to zoo

Meera spends a Sunday morning in her grandmother's kitchen garden in Kochi, among a mango tree, potato and brinjal beds, a Datura by the wall and a pot of Petunia, with the family dog underfoot and a housefly on the lunch. In the afternoon the family visits the zoo, where a lion, a tiger and a leopard sit in neighbouring enclosures. Every organism she meets that day gets a name, a group and a place on one ladder.

The lesson in notes

In short

Biodiversity is the number and the kinds of organisms present on earth. Each distinct kind of plant, animal or other organism is a species.

Between 1.7 and 1.8 million species are known and described so far, and new ones keep being identified, both in unexplored places and in well-studied ones.

The wider the area you observe, the more kinds of organisms you meet: a dense forest holds far more kinds than a school garden, and many organisms are too small to see with the naked eye.

Local names of one organism change from region to region even within a country, which makes it hard for people in different places to know they are talking about the same organism.

Nomenclature is the standardised naming of organisms so that one organism carries the same name everywhere in the world.

Identification comes before naming: the organism must first be described correctly so we know exactly which organism a name belongs to.

Plant names follow the International Code for Botanical Nomenclature (ICBN); animal names follow the International Code of Zoological Nomenclature (ICZN).

A scientific name is unique in two ways: each organism has only one such name, and that name is not used for any other known organism. A proper description should let anyone, anywhere, reach the same name.