Quinarian system

The quinarian system was a method of zoological classification which was popular in the mid 19th century, especially among British naturalists.

[1] The system was further promoted in the works of Nicholas Aylward Vigors, William Swainson and Johann Jakob Kaup.

The system had opponents even before the publication of Charles Darwin's On the Origin of Species (1859), which paved the way for evolutionary trees.

Another aspect of the system was the identification of analogies across groups:[3] [W]e shall consider that to be a natural system which endeavours to explain the multifarious relations which one object bears to another, not simply in their direct affinity, by which they follow each other like the links of a vast chain, but in their more remote relations [analogies], whereby they typify or represent other objects totally distinct in structure and organization from themselvesQuinarianism was not widely popular outside the United Kingdom (some followers like William Hincks persisted in Canada[5]); it became unfashionable by the 1840s, during which time more complex "maps" were made by Hugh Edwin Strickland and Alfred Russel Wallace.

[6] These systems were eventually discarded in favour of principles of genuinely natural classification, namely based on evolutionary relationship.