Question

Many of you are biology majors, and the rest of you have probably taken a biology class, so this week's discussion question is this: How much of Linnaeus' classification system survives today? Which part do you still learn in your classes? What, if anything, has changed in classification systems since Linnaeus' time?

Answer 1

The natural system of classification was developed by the botanist Carolus Linnaeus in 1970

He classified the organisms based on the natural characteristics of the organisms like morphological features.

So he is known as the father of taxonomy

He classified the organisms into the hierarchical groups called as TAXA

Kingdom --> Phylum/Division --> Class --> Order --> Family --> Genus --> Species

Diversity increases from Kingdom to species while similarities increases form species to kingdom.

Kingdom is the largest taxa with all organisms having few similar characteristics.

Example- kingdom: Plantae; Kingdom: Animalia

Genus consist of closely relate species grouped together.

Binomial Nomenclature system:

Linnaeus introduced the nomenclature system of organisms by naming it with two unique latin words as

1. Genus name
2. Species name

Example- Homo sapiens

This system is used until now to name the organisms

Modifications in Linnaean classification:

A new taxa above Kingdom was added called as Domain.

Three domains were defined as

1. Bacteria
2. Archaea
3. Eukaryota

Unicelluar, prokaryotic organisms are grouped under Domain- Bacteria, Archaea

While unicellular to multicellular eukaryotic organisms are grouped under Domain-Eukaryota

The Linnaean system was based totally on natural characteristics and not on the phylogeny. Therefore new the classification systems are introduced based on the phylogenetic characteristics

Example: APG System of Plant Classification