This time-lapse video by Mitsuru Yasui focuses on a room filled with cats, all of whom are determined to sleep in a narrow sunbeam streaming through a partially curtained window as it moves across the floor during the day. As a result, they create a furry line across the floor that moves as the sunbeam moves.

One pair of cats took a short break from their scientific work for a brief procreation attempt (0:51).