In mammals a tail appears physically as an extension of the backbone ("Chordata"- zoological classification of animals that have a backbone) is the central upright balancing hanger of adjoined parts of a creature.
If you reduce a tail to a Chordate, the most abstract is an Eel or Snake.
A tail can be thought of as an extra limb thats' mechanics may or may not be particularly dexterous or manipulative by its usage upon objects(except in Possums and Monkeys though they prefer to do much of and any dexterous manipulations of objects using any of the other limbs they have and sometimes but rarely the limbs adjoined to their pelvis' in preference to the limbs adjoining the neck and shoulders).
However, as a primitive simple or poorly functioning limb it only tends to commit protection of the sensitive genital area of creatures in land based animals when used as a limb for a function by the actual direct usage for manipulation of its being.
Definitely in dogs' and cats', emotional expression is abstractly obvious(definitely related to) related their tails manipulation by the tails' manipulator muscles having positioning or posture movements effected upon it deliberately.
Definitely also it is obvious that the backbone is a jarring(adverb) fastening against the shock waves of movement caused by usage of its adjoined limbs during traversal, of the tail will be sending back more shock waves amplified by the tails' position setting muscles' associate nerves and mechanical effect of gravity relating each shock cycle upon the fulcrum of the tail base.
The resulting usage of the resultant traversal shock cycle can indicate anything from fatigue to a forced repositioning of the tail by an external or environmental influence, inclusive, how well balance is being maintained in some situations of movement.
Tails appear to have their best usage in flight(running at top speed) whether as an environmental sensor(wind) or as a defensive sensor when fleeing (enemy touches its tail during running).
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However, carnivorous predating game for food requires a set of inbuilt drives psychologically that enable the dog to survive called predatory instinct(a primary directivein Canis), of this has a special part of it called "chase instinct".
As you have probably seen both kittens and puppies and even bigger varieties of either Canidae or Felidae chase their own tails and snap their teeth at them and once in a rare time injure their own tail mildly.This "chase instinct" has an extremely valuable point that it is part of the predatory psychological drive, that being it causes them impulsively to react at sudden movements with a rush of emotion or feeling to attack before it comprehends exactly the cause by recognition of the cause.This is a major part of their ability as a predator to survive.
Generally predators(quadruped mammal) all point their tail directly out behind them straightened when they start to chase.
When predators form groups or are alone to hunt but particularly in predators that catch prey by chasing these predators must move at immense speeds almost always to catch their prey.
This naturally is extremely dangerous but the final most important point is that because they are moving at top speed they "cannot simply stop or adjust course instantly or quickly if wind strikes side on" "unless they are disturbed enough".Because they are effectively a sail at side on to the wind a strong gust will throw them into a tree if they do not realize to adjust to the sudden mechanical environment change.
However alike a rabbit on the point of having no tail(a Bobcat or Lynx), they have ears that mechanically will be sensitive to strong wind gusts.
Yeah dogs know they have tails, That's why they chase them.
Yes technically wolves have longer tails than dogs. But sometimes dogs can have the same length of tails.
no they dont some dogs have little stubs as tails
Cats wag their tails because they are angry. Unlike dogs they wag them when mad but dogs wag their tails when they are happy.
no. dogs do not have prehensile tails because dogs do not use their tail for gasping things like a fifth arm.
MOST dogs are born with tails, but some breeds have them docked at birth.
some dogs have big tails because that is the size that fits their body
Because they get their tails docked.
Sometimes dogs use their tails to show emotion!
Usually a Veterinarian will dispose of the amputated tails.
Sometimes dogs use their tails to show emotion!
No dogs aren't the only animals that wag their tails.Sometimes cats wag their tails.
The reason dogs have tails is for balance
Because it is a sign that dogs are happy.
Labidoor Retrevers have curly tails. and so do keshoonds
wag their tails
They are not.
No it is cartilage
Yes But dogs that don't have tails don't
you should never cut a dogs tail off, it is very panefull and all dogs need tails.