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Introduction to Plant Taxonomy: Part 1, Domain

All life is organised by Taxonomic Rank. This system is used to separate forms of life by their characteristics. In terms of plant knowledge and understanding, the most relevant Taxonomic Ranks to be able to navigate are the lowest ranks of Family, Genus and Species. Articles discussing each of these ranks can be read by clicking on their name in the text, or to read in sequence, click on link at bottom the page.

Hierarchy of Life - Taxonomic Ranks
Hierarchy of Life - Taxonomic Ranks

To understand the higher orders in simple detail though, it is also worth reading this and the following articles on Domain (this article), Kingdom, Phylum, Class and Order before jumping to the lowest ranks.

To begin, let us look at the hierarchy of the rank. In theory, there is a higher tier Super Rank of 'Life', but we can assume that Life is organised from Domain to Species in all practical terms.

Domain in some texts may be referred to as Superkingdom, Realm or even Empire, but Domain is well-accepted as a common norm.

To all intents and purposes Domain is where all life is held. It is variously described as containing two or three domains of life (depending on the model being used), either Archaea, Bacteria and Eukarya or Archaea and Bacteria.

  • Archaea are single celled organisms lacking a cell nucleus.

  • Bacteria are mostly single-celled, but largely free-moving organisms. Some are essential for the life of other organisms, others can be deadly to other organisms.

  • Eukarya (sometimes included in Archaea) are both single and multi-celled organisms that contain a cell nucleus. Plants (Plantae), Animals (Animalia), Fungi and 2 other Kingdoms (Protozoa and Chromista) are included in Eukarya and are more commonly called eukaryotes.

We next look at Kingdoms, the second tier of the Taxonomic Rank.

A useful and readable book to guide you through the fundamentals of Botany including taxonomy.

Another straightforward guide, perhaps more focused on botany.

A book for anyone who likes the subject a LOT!