How is ego death philosophically possible? I hear what you are saying, and you're right to say that animals do have a sense of time. Animals
do have a circadian rhythm for example. However, what Tolle means by "time" or having a "sense" of it, is the anxiety that comes with the need to meet a deadline, needing to wake up early, or running late for instance - being "on time" as we know it.
In this way, an animal does
not have a "sense" of time, as they are not held to the same expectations (many of these expectations being unnecessary and sort of arbitrary - but ultimately result from the human condition - according to Tolle), as us. For example, having a job, and the "on-timely" nature that comes along it, is
not an expectation we have of animals.