Lesson 7 of 8 · 6 min
Phylum, kingdom and the hierarchy table
NCERT §1.2.6–1.2.7
On the way out of the zoo, Meera passes the aquarium, a frog pond, a snake house and an aviary. A fish, a frog, a lizard, a bird and her own dog: what could they possibly all have in common?
The lesson in notes
In short
A phylum is a group of classes. Fishes, amphibians, reptiles, birds and mammals share a notochord and a dorsal hollow neural system, so they are placed in the phylum Chordata.
In plants, classes with a few similar characters are grouped into a higher category called a division, the plant counterpart of a phylum.
Kingdom is the highest category. All animals from the various phyla form Kingdom Animalia; all plants from the various divisions form Kingdom Plantae.
Moving up from species to kingdom, the number of characters shared by members goes down. The lower the taxon, the more characteristics its members share.
The higher the category, the harder it is to work out its relationship to other taxa at the same level, so classification grows more complex towards the top.
Man: Homo sapiens, genus Homo, family Hominidae, order Primata, class Mammalia, phylum Chordata.
Housefly: Musca domestica, genus Musca, family Muscidae, order Diptera, class Insecta, phylum Arthropoda.
Mango: Mangifera indica, family Anacardiaceae, order Sapindales, class Dicotyledonae, division Angiospermae. Wheat: Triticum aestivum, family Poaceae, order Poales, class Monocotyledonae, division Angiospermae.
Taxonomic studies of plants and animals are useful in agriculture, forestry and industry, and in knowing our bio-resources and their diversity.