Full Idea
The richest source of illustrations is the vegetable kingdom, where specific differences tend to be much less clear than among animals, and considerable developmental plasticity is the rule.
Gist of Idea
Borders between species are much less clear in vegetables than among animals
Source
John Dupré (The Disorder of Things [1993], 1)
Book Reference
Dupré,John: 'The Disorder of Things' [Harvard 1995], p.27
A Reaction
Nice. Just as the idea that laws of nature are mathematical suits physics, but founders on biology, so natural kinds founder in an area of biology to which we pay less attention. He cites prickly pears and lilies. I'm thinking oranges, satsumas etc.