Why some mammals can sleep on their feet?
Horses can fall asleep while standing. Horse's legs are structured in a special way, in which they can lock their knee bones in a specific position, and in this state they can relax all the muscles in their body. Such behavior is an important mammal feature because from a standing position they are always prepared to wake up and start running right away if they sense a predator nearby. However, If a horse feels safe, it can lie down and reach deeper phases of sleep.
Cows and giraffes also possess this unique ability.
What are your thoughts on this subject?
19 Comments
Kevin Coleman
The correct answer isn't there. It's a safety factor. Really poor question
Carole Houck
This is one of the most poorly written questions I’ve seen.
Ronald Schertz
This is far from the real reason. Very bad response choices.
Jacqueline Tattam
This should never have passed review!
scottlarock
same thing...
John Wheat Jr
Terrible question! Wrong answer given! Grammar of question is ludicrous! Is this suppose to be a joke! I am not laughing, give me my points and continue my streak of correct answers!
Clayton Dean Brannon
Good question. One answer is misleading. It is not that they have a problem lying down it is they can not get up fast enough to prevent being caught by a predator. Locking joints is the best of the two possible answers.
dowill
The best answer is "It is hard to get up if they lie down". Many animals sleep standing up because of danger from predators. If it is hard for them to get up, they cannot easily escape when a predator attacks.
Naked Kitty Slave
Gery Tillmanns, took the words right out of my mouth. There's no author credited ergo believe this grammar hot mess is compliment of the QC Robot.
Lorna Lake
Totally agree with others here - badly phrased question - and wildly inaccurate statement as an 'answer'!
Gery Tillmanns
How did this get past the review panel?
Dwainfb Fitzpat
Just another bad editing example of a bad question and answer. It's been getting really rough lately even figuring out the question.
Belgasem Goma
ans. 1 also corect bec. same aim to get prepared for any danger
Pat Butler
This is how they do it, not why they do. They do it as an evolutionary means of protection from predators because they have trouble getting up. Horses still have to lie down occasionally to get REM sleep and elephants risk damage to internal organs and have trouble getting up from the terrain in which they generally live .
Roger Blackstone
I should have refered to my Wal-Mart to English translator for this one...