Biologging for the future: how biologgers can help solve fundamental questions, from individuals to ecosystems

Archival instruments attached to animals (biologgers) have enabled exciting discoveries and have promoted effective conservation and management for decades. Recent research indicates that the field of biologging is poised to shift from pattern description to process explanation. Here we describe how biologgers have been - and can be - used to test hypotheses and challenge theory in behavior and ecology through three case studies and many short examples. These examples, spanning predator-prey interactions, state-dependent risk-taking, resource tracking, and collective movement decisions, show how biologging can resolve long-standing mysteries if research is designed with a solid conceptual foundation. The next phase of biologging science will require scaling studies from individuals to populations and possibly to ecosystems. It will also benefit from building equitable international and interdisciplinary partnerships, bridging the terrestrial-marine divide, and addressing ethical conundrums including animal handling and open science practices. Doing so will help cement biologging as an indispensable tool for producing generalizable knowledge about how organisms and ecosystems function.