Although dogs and cats have different ancestors and occupy different evolutionary niches and they were domesticated via different processes, they have both co-existed with humans for thousands of years and still remain the most commonly kept pets. It has been argued that the foundation of this successful co-existence with humans is through non-verbal communication. Animals use their extraordinary senses of smell, hearing, touch, and eyesight to communicate with humans to help develop and maintain relationships. Researchers have compared the ways in which dogs and cats interact with humans to help gain insights into how both species have successfully integrated into human society.
Recent studies have explored how dogs will change their behavioural responses in relation to their owner’s direction of ‘gaze’. For example, dogs were found to be more obedient to their owners’ commands when their owners looked directly at them, and dogs were more likely to look in the same direction in which the human handler gazed. Not surprisingly as solitary hunters, cats have a different communication style with humans. Cats familiar with a human do appear to follow the human gaze, but whether they avoid or follow the human gaze appears to depend on the social context. Other forms of perceptual information may have more significance for promoting bond formation. For example, cats seem to have adapted their vocal sounds to more effectively communicate with humans; adult cats will ‘meow’ at humans, whereas meowing is generally only used for communication between kittens and their mothers. Research such as this into the human -animal relationship helps us to understand the bond we have and how we have co-existed and potentially co-evolved, but also highlights that it’s likely that our animals are better at reading our behaviour than we are at reading theirs.
However, this doesn’t have to be the case. One of the wonderful things about sharing our lives with companion animals is being able to appreciate the nature of the different behaviours they perform, providing us with the opportunity to gain an insight into the world from their perspectives. If we are to truly appreciate the differences between us and our animals, we need to understand how their evolution has shaped their behaviour including their reliance on their sensory capabilities. Senses are defined as;
"Systems that consists of a group of sensory cell types that responds to a specific physical phenomenon, and that corresponds to a particular group of regions within the brain where the signals are received and interpreted."
Traditionally the main five senses are reported to be sight, hearing, taste, smell and touch, but it’s also recognised that there may be more systems that respond to electrical or magnetic forces, chemicals and even water pressure changes. These additional senses are often seen to varying extents in different animal species living in environments where traditional senses may not be enough for equipping the animal for survival. Electroreceptive animals like sharks and electric eels, or surprisingly Australia’s fascinating monotremes like the platypus, use self-generated electric currents to locate objects in the same way as the native bats of Aotearoa use their echolocation to map out their surroundings when flying. This is especially important where animals occupy habitats in which they cannot depend on their traditional senses like vision: for example where they live in dark caves, in murky water and are busy at night.
Unlike us humans who don’t make good use of their full range of senses for interacting with their environment – dogs and cats rely on all of their different senses, often with special modifications to accommodate their different lifestyles. You only need to look at your dog or cat to see how much they rely of their senses for navigating their worlds –with natural and artificial selection providing for the wide variety of breeds of cats and dogs with different shaped ears, noses and eyes – all of which will impact on their sensory perceptual abilities.
Dogs have a remarkable ability to detect and discriminate between different scents, and certain breeds of dogs are better at this than others depending upon the shape and size of their noses. Having good ‘smellyvision’ enables dogs to navigate their world through the odours that have been left by other animals, as well as gathering information about the timeframe during which these were left. It’s amazing to consider that dogs and cats can detect when another animal (or human) has been in the area and they can use this information to make decisions regarding whether to avoid or confront the invader, or to attract a mate as they see fit. Most people will be familiar with their dogs appearing to cover up the scent of another dog when out on a walk, but have you ever wondered how they do this, and why it has evolved?
We make good use of the dog’s superior sensor capability in many of our utility or service animals. Scent dogs with impressive noses such as bloodhounds, have incredible abilities, they possess up to 300 million olfactory receptors in their noses, compared to about six million in us. The olfactory power of dogs means that they can be trained to detect various odours such as specific drugs and explosives, and even certain human cancers or human disease conditions (eg diabetes) by smelling breath, skin or urine samples. With scent being so central to the dog’s quality of living, its important to provide them with the opportunity for ‘sniffy’ walks- rather than purely exercise walks/runs/cycle rides where there is no opportunity for the dog to stop at will and explore a smell.
And let’s not forget how cats use odour to explore their world. They have an extraordinarily good sense of smell, particularly in their detection and use of scent molecules called ‘pheromones’. They use a special adaptation called the vomeronasal organ which is in their upper palate to draw the scent molecules over the sensitive structure to help them gain as much information about the chemical message as possible. The flehman response where the cat raises its upper lip, helps to capture the scent/chemical message so that the cat gets as much information as possible out of the tiniest odour. Cats secrete and spread pheromones through special glands located in their chins, cheeks, lower ears, forehead, and paw pads. The affectionate behaviours cats show towards their familiar guardians, chin-rubs, head bumps and kneeding are all a way to communicate their presence and their ‘ownership’ of you, to other animals that may come near you.
Of course, we also know that cats are far superior to humans in their ability to see in dark conditions. This is due to particular muscles surrounding the iris of their eyes as well as a specialised reflective surface right behind their retinas, called the tapetum. The glowing eyes of your companion cat at night is a wonderful adaptation that enables cats to extend feeding or hunting beyond daylight hours, meaning they can feed on nocturnal creatures, and are often motivated to be active when their human guardians have gone to bed. This physical and behavioural adaptation to allow for nocturnal feeding and living, is something we need to be mindful of when considering how we keep cats in the domestic situation.
When you look at the world through another species’ eyes/ears/nose – you get to appreciate just how different we are to them. It’s clear that whilst as species we may have co-existed and we believe that we enjoy a special bond with our pets. It’s important to appreciate that our companion dogs and cats enjoy a secret life; they have different needs, different motivations and enjoy different experiences. As responsible guardians we need to appreciate these species differences and find ways to improve our understanding of them and their style of communication so that we can provide them with the living environments and experiences that enable them to make good use of their amazing sensory capabilities and live a Good Life.
If you want to learn more - The Truth about Cats and Dogs is a free online course that you can access to learn more about the amazing abilities of our companion animals Sign up for free (yes its completely free) here https://www.coursera.org/learn/cats-and-dogs