An erect ear helps to prevent bacterial, yeast, & fungal infections, and also improves hearing as well as detecting the direction of sounds. All wild land mammals, and certainly every species of wild canines and felines have erect ears. Even an elephant's ear is not floppy, as its huge ear is self supportive while its sways forward and rearward. Elephants can hold their ears straight out should they wish to do so, as demonstrated during echolocation, thermal regulation, and communication. Their ear certainly does NOT droop over their ear canal.
ERECT EARS ARE MORE NATURAL THAN FLOPPY EARS - The reason all wild canines and felines have erect ears is simply because it is superior in health and function. Ear cropping is for not done for “just cosmetic reasons," yet this procedure is being outlawed in some countries, which is emotional foolish motivated by people that do not understand the basis of natural selection.
Wild animals with erect ears only have floppy ears when they are infants. The reason the ear on so many domestic dogs is floppy is simply because breeders of dogs have selected the exaggerated neoteny like phenotype. This practice with domesticated species has resulted in the production of individuals that display youth like features even after they have matured. When the floppy ears of domesticated canines are properly cropped (during puppy-hood and with a functional amount of length), ear cropping is simply a corrective procedure that reverses the downfalls of domestication and breeding practices that resulted in the inferior floppy ear.
The longer the ear or the older the pup, the more likely it will need to be taped in order to stand. I prefer to avoid taping the ear when possible, as almost all problems with ear cropping can be eliminated if one does not need to tape the ear. Taping the ear can lead to infections or discomfort, which may influence temperament in young pups when they should be imprinting on positive relationships and behaviors.
For this reason, I prefer to avoid really long ear crops and also prefer to avoid cropping older puppies. Puppies with thick heavy ears should be cropped earlier (between 6-9 weeks of age) or cropped shorter than average to avoid issues or complications with standing erect on their own. Puppies with thinner lighter ears can be cropped from 7-14 weeks of age without issues. When dogs with thin skinned light weight ears are cropped between 6-8 weeks of age, they can typically be cropped rather long and still stand without much or any taping.
I prefer the mid-length crop, which is long enough to function like the wild (natural) ear...an ear that is able to funnel sounds into the ear canal and turn like a satellite to determine direction of direct sounds. The mid-length crop is short enough that the ear generally stands in less than a week and certainly by the time the stitches are removed 7-10 days later. We now only have the shorter ear crops done when pups are older than 9 weeks of age or have thick heavy ears.
The satellite shape of the ear funnels sound into the ear canal, which helps hearing and also helps with locating the source of such sounds. Early hearing aids for humans were based off this concept. And as stated earlier, ventilation is also important in terms of health.
Before buying too much into the philosophy that the tail is "necessary for balance," let's remember the bobcat and lynx both have short to mid-length tails and yet they are some of the most acrobatic cats on the planet. Not only are these cats apex predators and fighters, but let's also consider they are fighters that hunt in trees. These cats must have excellent balance on limbs as they climb or jump through the forest, yet they have short tails. These cats are not high speed coursers that hunt on the prairie. Being they hunt in the trees, they are designed for close quarters combat, not high speed direction changes. The tail's "counter-balance" abilities are more like rudder than a balancing pole. Our dogs are not high speed coursing hounds, they are combatants...like the bob-cat and lynx...both of which have a mid-length tail.
For smaller dogs, a full length tail is less problematic, but for large dogs it can be a problem. The American Sentinel is a large gladiator breed, and should not be confused with a sight hound chasing an agile rabbit at 40 mph. No, they are close quarter gladiators. Even the dogs we use as catch dogs to catch wild boar are generally speaking not high speed coursing hounds. The dogs we use to catch wild hogs are catching wild dangerous game that fights back.
The long tail is much more prone to injury, especially where people and doors grab tails, and where walls are not "just around the corner," but actually create every corner found in a domesticated world. I have seen a dog's tail have the hide ripped off when it was ran over by a car...and it is easy to imagine criminals working as a team using the dog's natural long tail against him. I have also seen large dogs with long tails wag them so much that they damage the tip and sling blood daily as the wagging tail has difficulty healing when it is continuing to beat against the walls in our homes. Animals in the wild are not bound by such close barriers. Finally, a long tail also knocks over drinks and candles, and hits children in the eyes...all of which can be avoided when the tail is partially docked.
So, now one might ask, why not a complete docking of the tail? I like to see the dog communicate with its tail. It is an expression of mood and/or energy. It can also protect the vital organs of the anus and reproductive tract when in combat, such as hunting. For this reason, I like the mid-length tail dock. It provides the benefits of a full tail without the draw backs of the full length tail...and also provides the few benefits the long tail has in a domestic society.
Now, all that said, I do not think it is wise to dock the tail on an adult. The nervous system becomes more developed as pups age and adult dogs have learned not only learned movements of their tail, but also develop more nerve endings. For this reason, I believe tails should be docked around 7-10 days old. Sometimes it takes a day or two after delivery for a mother to produce sufficient milk for the litter. As a result, the puppies often lose weight the first couple of days. For this reason, I do not dock tails before 5 days of age because I want to make sure all the pups are in good condition and are gaining weight before their tails are docked.