This is the final version. Available on open access from Nature Research via the DOI in this record.Due to the sensitive nature of reporting on elephant locations and
numbers, the data that support the findings of this study are available on reasonable request from the
corresponding author.In long-lived social species, older individuals can provide fitness benefits to their groupmates through
the imparting of ecological knowledge. Research in this area has largely focused on females in
matrilineal societies where, for example, older female African savannah elephants (Loxodonta
africana) are most effective at making decisions crucial to herd survival, and old post-reproductive
female resident killer whales (Orcinus orca) lead collective movements in hunting grounds. In
pathways in Makgadikgadi Pans National Park, Botswana, we found that the oldest males were more
likely to lead collective movements. Our results challenge the assumption that older male elephants
are redundant in the population and raise concerns over the biased removal of old bulls that currently
occurs in both legal trophy hunting and illegal poaching. Selective harvesting of older males could
have detrimental effects on the wider elephant society through loss of leaders crucial to younger male
navigation in unknown, risky environments
