* Sleep patterns: Some animals sleep very little, but others may have periods of deep sleep interspersed with periods of alertness.
* Cognitive complexity: Animals with more complex brains may have different levels of consciousness and awareness.
* Behavioral adaptations: Some animals are naturally more active and alert due to their environment or prey/predator interactions.
That being said, here are 10 animals often considered to be highly alert and active:
1. Dolphins: Dolphins sleep with only half of their brain at a time, allowing them to remain constantly vigilant.
2. Elephants: Elephants are known for their intelligence and social complexity. They are highly aware of their surroundings and can be very protective of their families.
3. Horses: Horses are prey animals and must be constantly alert to potential dangers. They have excellent eyesight and hearing.
4. Birds of prey: Hawks, eagles, and owls are highly visual predators that spend a lot of time scanning their surroundings for prey.
5. Chimpanzees: Chimpanzees are highly social animals and are known for their problem-solving abilities. They are also highly alert to potential threats.
6. Dogs: Dogs are known for their loyalty and alertness. They are often used as guard dogs and can be very protective of their owners.
7. Cows: Cows are ruminants and spend a lot of time chewing their cud, which requires a state of semi-alertness.
8. Cats: Cats are often considered to be very independent and self-sufficient. They are also known for their predatory instincts and are highly alert to movement.
9. Squirrels: Squirrels are very active and constantly foraging for food. They are also highly aware of their surroundings and can be very quick to escape danger.
10. Rats: Rats are known for their intelligence and adaptability. They are also highly alert and can be very quick to learn new things.
It's important to remember that this list is just a starting point. Many other animals could be included, and there is no single "top 10" list that everyone would agree on.