Ah! I think I found an explanation of Free Will that I can work with.
‘Martin Heisenberg (son of Werner Heisenberg of uncertainty principle fame) has interesting things to say about free choice as well. If we understand free will in its most basic form—”randomness followed by lawful behavior”—Heisenberg argues that while animals aren’t “conscious” or self-aware like humans, even unicellular organisms exhibit these kinds of choices:
“Although we do not credit animals with anything like the consciousness in humans, researchers have found that animal behaviour is not as involuntary as it may appear. The idea that animals act only in response to external stimuli has long been abandoned, and it is well established that they initiate behaviour on the basis of their internal states, as we do.” -Martin Heisenberg (Nature, vol. 459, 2009, p.164)