Which of these describes punctuated equilibrium? a. rapid periods of speciation over a long time b. long periods of no speciation interspersed with short bursts of speciation c. gradual changes over a short period of time d. periods of medium speciation followed by periods of rapid speciation

Punctuated equilibrium is the theory that evolution occurs in sudden jumps, after which newly differentiated species exist in a state of stasis until the next jump. This is contrasted with theories which hold that evolution and speciation take place through a process of gradual adapatation. Thus, the correct answer is B, long periods of no speciation intersperced with short bursts of speciation.