Think of a prick-eared canine and your thoughts may swing from their wolf-ancestor to the ever-popular French bulldog. That enormous radar-dish of an ear is so expressive, flicking this way and that, as the dog focuses sound.
Indeed, the prick-ear is the equivalent of a natural ear trumpet. In the same way that we cup a hand around the ear to hear more clearly, so a prick-ear focusses sound. It works by collecting the sound waves and bouncing them down into the ear canal for processing.
It, therefore, stands to reason that breeds with drop-ears, such as the Beagle, Bassett Hound, or Bloodhound, don't hear as well as prick-eared dogs. Is this the case?
Actually, yes it is...although those drop ears come with their own advantages, especially when it comes to following a scent trail!
Signs of a Floppy-eared Dog Hearing
Anyone who has owned a drop-eared dog will appreciate the subtle body language of the ear and how it being drawn into different positions means different things. The ability of the dog to exhibit these different positions is strongly influenced by the size and weight of that dropped ear.
For example, a small triangular flap ear, such as a pug's, can be held back away from the head, pricked up, flopped down and more. However, contrast this with a breed such as the Cocker Spaniel, who has heavy, dangly ears coated in luxurious fur, or the long, heavy ears of the Bloodhound, and you see they are physically unable to lift the weight of those ears.
But remember, even though those drop-ears act as a muffler to sound, the canine ear is still much more sensitive than the human ear. Not only can dogs hear much quieter noises, but they can hear a wider range of sounds, and detect them from a greater distance away than we can.
- Head tilting
- Ears drop
- Ears back
- Ears up
- Turning the head
- Pausing to listen
- Change in body language in response to the sound
History of Dogs with Floppy Ears
In short, no one is 100% certain.
Sure, selection for specific physical characteristics such as coat type, leg length, and body shape led to the development of different dog breeds. But digging more deeply, why did the genetic changes from the wolf-type take place in the first place?
One theory is that floppy ears developed as part of the domestication syndrome. This means that it was the more friendly wolves, rather than the ferocious ones, who first struck up a relationship with early-man. Scientists argue that these more docile wolves had smaller adrenal glands. (The adrenal gland gives of the 'fight or flight' hormones, which can make a dog more prone to aggression.) The adrenal gland itself is derived from a group of germ cells called the 'neural crests cells', which also supply parts of the ear.
It could be that dogs with smaller adrenal glands also have less far-reaching neural crest cells and that if these don't fully reach the ear, it may lead to a 'drop' ear. However, this is just a theory.
What we can say with certainty is that if man took a liking to a particular look or physical trait in the dog, then when he selectively bred dogs showing this characteristic, it lead to the development of a new dog breed. In addition, each of these breeds often had heightened senses or skills in different ways...leading to scenthounds, hearing hounds, and sight hounds.
The Science of Floppy-Eared Dogs
The Bloodhound is an example of a scent hound whose skill is picking up scent molecules and tracking them. This specialization led to an increased surface area of scent-sensitive receptors in the nose along with a larger olfactory center in the brain than other breeds.
So what about their ears?
Actually, those ears aren't such an encumbrance as they look, dragging along in the dirt. It's now understood that floppy ears in scent hounds serve a number of purposes.
The first is that as the dog moves along, the floppy ears cause micro-air currents which help sweep scents up towards the nose. And the second is that scent molecules actually adhere to the ears and help 'offer up' the smell to the nose. Who'd have thought?
Training a Floppy-Eared Dog to Hear Well
However, a dog still has much more sensitive hearing than a human - it's just a question of maximizing this potential.
To have a floppy-eared dog hear well, it's crucial to take care of the ear canal and ear flap.
For example, if you have a heavy-eared Cocker Spaniel and their ear flap has a thick, luxurious coat of fur on both the inner and out surface, the hair can muffle sound significantly. You may wish to clip the hair from the underside of the flap and remove some of the impediment to sounds waves.
Likewise, take a look to see if your dog has hairy ear canals. The practice of plucking ears is controversial. For dogs with hairy canals that regularly get infections, some vets promote plucking as a way of improving air circulation.
However, there's a counter-argument that this inflames the skin lining of the canal and traumatizes it. Whatever the rights and wrongs from a health perspective, plucking will help the dog to hear.
Also, pay attention to ear health. An inflamed ear or one full of wax is the equivalent of wearing an earplug, so regular ear cleaning is a must for dog's with waxy ears, in order to keep the ear canal patent.
Safety Tips for Dogs with Floppy Ears:
Practice good ear cleaning from puppyhood onward.
Take extra care after your dog goes swimming.