10. Bullfrog (Rana catesbeiana) Bullfrogs can remain dormant and motionless for extended periods, leading some to believe they don't sleep. However, they do experience periods of rest.

09. Bull Shark  (Carcharhinus leucas) Bull sharks have been observed to engage in continuous swimming without showing signs of traditional sleep. They display modified sleep patterns that allow them to rest while remaining active.

08. Bottlenose Dolphin  (Tursiops truncatus) Dolphins employ unihemispheric sleep, meaning they sleep with one hemisphere of their brain at a time while the other remains awake. This allows them to maintain vigilance even during rest.

07. Giraffe (Giraffa camelopardalis) Giraffes sleep in short bursts  of a few minutes at a time,  totaling only a couple of hours  per day. They often sleep standing up, and their brief sleep periods help them stay alert to potential threats.

06. African Elephant  (Loxodonta africana) Elephants have short sleep cycles  of about 2-3 hours per day.  They can sleep while standing  or lying down and often doze  off in a relaxed position,  leaning against a tree.

05. Rhopalocera (Butterflies) Rhopalocera, or butterflies, are colorful insects with delicate wings. They undergo metamorphosis, captivating us with their  beauty and graceful flight.

04. Bull Ant (Myrmecia pyriformis) Bull ants, known for their aggressive behavior, don't sleep in the traditional sense. Instead, they have brief  periods of rest where they  become less active but remain alert.

03. Albatross (Diomedea spp) Albatrosses are known for their long flights across vast oceanic distances. During these flights, they engage in a type of sleep called "microsleep," where they briefly rest with one eye open.

02. Cows (Bos taurus) Cows have been observed to exhibit reduced sleep patterns, often sleeping in short periods of 4-5 minutes while standing up.  They spend most of their time grazing and ruminating.

01. Jellyfish Jellyfish lack a central nervous system, including a brain, and therefore don't sleep as we understand it. They are in a  constant state of rest,  floating and pulsating in the water.