Full Idea
Of those ignorant of the Self (Atman), some enter into beings possessed of wombs, others enter into plants - according to their deeds and the growth of their intelligence.
Gist of Idea
Those ignorant of Atman return as animals or plants, according to their merits
Source
Anon (Upan) (The Upanishads [c.950 BCE], 'Katha')
Book Reference
'The Upanishads', ed/tr. Prabhavananda /Manchester [Mentor 1957], p.22
A Reaction
"I sigh and sigh, and wish I were a tree" wrote George Herbert. You probably need the snobbery of the Indian caste system to appreciate the horrors of low rebirth. I quite fancy being a dolphin, but a tulip would be all right.