You’ll Be Surprised by How Much These Animals SleepBy admin / November 30, 2017 / Fun Even their name gives away their small stature. Little Brown Bats weigh an average half an ounce and are only 6-8cm in length. In a 1969 study, it was revealed that these tiny creatures slept for 20 hours in a 24-hour period. Pages: 1 2 3 4 5