The visiting hairy insects in the cup of this Roella incurva flower are well covered in pollen. This hairiness may have evolved from pollinating flowers better.
Better pollinated flowers may have survived better from better seed set, feeding their insect partners better. Better fed insects survived better until breeding, reproducing betterto serve their flower partners better. These unlike species, one from the Animal Kingdom, the other from the Plant Kingdom are not married but inextricably involved for keeps in order to survive.
Evolution favours symbiotic problem solving or obstacle surmounting arrangements. So plant and insect may co-evolve as they fulfil survival needs for each other mutually.
Nature does not have a mainframe computer-like brain to work out such contracts. It took untold failed cases, holocaust scale pre-reproduction deaths to reach one solution. And there hadn't even been a war on! Specimens on both sides of the successful bargain, meeting partner requirements, survive better statistically from symbiosis. War would mean antibiosis.
Evolution is a biosphere wide roulette of millions of failures, meaning premature death, combined with many miraculous successes of saved species brought about by functional reproduction.
Humanity exhibits recurring urges of ascribing higher order spiritual misunderstanding to this higher order natural process.