Abstract: A system comprising at least one hardware processor; and a non-transitory computer-readable storage medium having stored thereon program instructions, the program instructions executable by the at least one hardware processor to: receive, as input, a signal representing temporal beat activity in a mammalian, receive indication of user selection of an integration level of said beat rate activity, receive indication of user selection of a species of said mammalian, and determine heart rate variation (HRV) in said signal, based, at least in part, on said type of said beat rate activity and said species of said mammalian.