Since animals continually evaluate their constantly changing environments and re-adjust their priorities accordingly through real-time actions, their natural movement trajectories are complex and stochastic rather than deterministic [ . . . ].

Deakin AG, Spencer JW, Cossins AR, Young IS, Sneddon LU. Welfare Challenges Influence the Complexity of Movement: Fractal Analysis of Behaviour in Zebrafish. Fishes. 2019; 4(1):8.