B2 revision - classification.

Classification is organising living organisms into groups.

classification systems can be NATURAL or ARTIFICIAL:

NATURAL CLASSIFICATION SYSTEMS are based on the EVOLUTIONARY RELATIONSHIPS and genetic similarities between organisms.
ARTIFICIAL CLASSIFICATION SYSTEMS are based on APPEARANCE rather than genes. They're used to IDENTIFY organisms.

living things are divided into KINGDOMS (e.g the plant kingdom).
the kingdoms are then subdivided into smaller and smaller groups - phylum, class, order, family, genus, species.

a genus is a group of closely-related species - and a species is a group of organisms that can INTERBREED to produce FERTILE OFFSPRING.

many organisms share characteristics of multiple…