evolve   verb
 to (cause to) develop gradually
 How do we know that humans evolved from apes? [I]
 The company has evolved over the years into a multi-million dollar organization. [I]
 Bacteria are evolving resistance to antibiotics faster than new chemicals are being invented. [T]

 evolution   noun [U]
 Research on insects suggests that bacteria play a vital part in animal evolution.
 This decision marks yet another change of direction in the evolution of the country's education policy.
 The programme traced India's evolution since independence.
(Cited from Cambridge International Dictionary of English.)