A plurality of electronic signals corresponding to a histological and/or physiological marker, such as a heartbeat, are obtained, from an individual and are converted into electronic signal form. The signals are measured to obtain an actual measurement of a plurality of variable features of the electronic signals relating to the heartbeats. The measurements are mathematically analyzed to provide the probability of divergence of each actual measurement. Using the calculated probability of divergence, subsequent received waveforms measurements are analyzed for authentication purposes.