Keep in mind that urine can change in color due a variety of reasons, dehydration being one of the most common. However, urine can be discolored due to medications, certain foods (i.e., beets), or as a side effect of health conditions (i.e., liver disease).
These terms describe when an animal is most active: 1  Nocturnal - active primarily at night. 2  Diurnal - active primarily during the day. 3  Crepuscular - active primarily during both dawn and dusk. Many animals that are casually referred to as nocturnal are actually crepuscular.  Metaturnal - active part of the day and part of the night.
While most humans are diurnal, for various personal and social/cultural reasons some people are temporarily or habitually nocturnal. The most known creatures to be nocturnal include cats, rodents, and owls, which all have heightened senses (including sense of sight).