The domestic cat (Felis sylvestris catus) has evolved from an ancestor that lived in an environment in which food was scarce and hard won (Fraser, 2012). Although this situation is not too far removed from the circumstances experienced by the many millions of feral, and many stray, cats throughout the world (Bradshaw et al, 2012), the human population often has expectations that the domestic cat's behaviour will vary considerably from that of their less cosseted, feral conspecifics (Cat Protection, 2017). Yet, the domestication process for the cat is a relatively recent journey (Serpell, 2000), leaving little time for the major genetic changes that would be required to provide a behavioural repertoire far removed from their less domestically adapted cousins. To better meet the behavioural welfare needs of the kitten bound for a role as a domestic cat, it is important to understand the potential limitations that the cat may have on meeting owner expectations of a companion, and the consequent support that both kitten and owner may require from the veterinary team (Ellis, 2016). To do this, it can be useful to consider the cat's ethology — where it came from and the behaviours that developed as part of its evolutionary journey (Bradshaw et al, 2012).
The journey from wildcat to domestication
The earliest evidence of our domestic cat's original ancestor comes from 11 million years ago (Bradshaw et al, 2012) and from this evolved a range of species including the ‘wild cat’. Of these it is the African/Arabian wild cat, Felis sylvestris lybica, that produced F. sylvestris catus, our modern, domestic cat. However, the cat's relationship with man would appear to be a relatively recent development (Serpell 2000). A sub-set of wildcats with a lowered ‘flight’ instinct is likely to have been attracted to the relative abundance of rodents feeding within the Egyptian grain stores, built around 11 500 years ago. In this way, these cats became accidentally adapted to living in proximity to man, becoming tame and embarking on the journey to domesticity (Bradshaw et al, 2012). However, it was not until about 1100 years ago that cats were brought to Europe, functioning as rodent control in Viking ships (Serpell, 2000). Yet despite tolerance of cats for their excellent capacity for rodent control in European households, their association with ‘witchcraft’ and pagan activity created an impediment to their acceptance as social companions and, despite their popularity as companion animals in US and European cities, the ‘ownership’ of cats remains tenuous in many countries, and many cities have large feral cat populations (Bradshaw, 2012). Whether living in a domestic home or surviving as a stray or feral cat, the need to find food via active predation has remained an essential part of the cat's capacity to survive. With evidence that cats in urban domestic environments may have to cope with a feline population of up to 3000 cats per square kilometre (Liberg et al, 2000), the domestic pet cat may find the stress associated with the domestic environment too great and may have to return to the stray population at any time — one American study (Rowan and Williams, 1987) suggests that up to 25% of the feline population fails to cope with domesticity and returns to a feral or stray lifestyle, each year. This tenuous hold on a secure supply of food within a domestic home further emphasises the innate need for the cat to continue to practice predatory skills.
The need to find food for survival and its implications for domestic behaviour
As the majority of the world's cats continue to live feral or stray lifestyles, the cat's behavioural repertoire is still a developing process that is largely governed by a continuing requirement to predate. The feral cat requires between 12 and 15 successful kills per day for survival (Rochlitz, 2009; Bradshaw et al, 2012), but with a success rate as low as 10%, maintaining this minimum kill rate may take up to 150 predatory attempts per day. As a consequence, the feral cat has a requirement to retain the predatory activity of its ancestor — the wildcat that predated on rodents within a savannah type environment — because rodents are scarce, solitary activity was a pre-requisite for survival (Fraser, 2012). With the relatively short period between the cat's primary domestic role as ‘rodent controller’ to ‘domestic companion’, and only recent (1960s) recognition by pet food manufacturers of the cat's specific dietary requirements, predation has remained an essential part of the cat's behavioural repertoire (Fitzgerald and Turner, 2000). Hence, the motivation to predate not only dictates much of the cat's sensory development (Bradshaw, 2012), but also influences much of its behavioural development (Bateson, 2000) and social behaviour (Crowell-Davis, 2003).
Predation-related genetic and early environmental effects on the kitten
The cat's physique is designed around its need to predate: its tail aiding balance; its sense of sight highly attuned to the smallest of movements that may predict the presence of prey and specifically designed to function efficiently in light intensities at dusk and dawn when rodent activity is at a maximum (Bradshaw, 2012). However, as the cat is also predated on by larger mammals, its eyes are displaced to the side to enable awareness of the approach of dangerous stimuli, disabling the cat's capacity to see, at short range, what is directly in front of it, so its sense of touch is refined to include extra sensory input from paws, whiskers and incisors teeth — necessary for the final pounce and kill of rodent prey. The cat's sense of olfaction not only enables it to detect the palatability of food, but it is adapted to enhance the cat's concept of territorial mapping. The cat's requirement for extra sensory feedback from whiskers and other specialised sensory systems, during the final pounce and kill, has left the cat with a reduced capacity to learn about the significant visual cues within its territory; instead, the cat relies on olfactory feedback from the pheromone marking left within the area by itself and other cats — carefully undertaking an olfactory inspection of all potentially significant points within the environment (Bradshaw et al, 2012). Such marking and olfactory activity enables the cat to create an awareness of areas where it has an expectation of challenge compared with areas that are familiar, in which core resources can be accessed with ease. It is for this reason that the kitten and cat require a consistent olfactory environment within the home, if it is to cope and gain a concept of ‘control’, and hence security, within its environment (DePorter, 2016).
Further behavioural influences of the need to predate for survival
In cats, hunting continues despite a surfeit of food — if hunting was delayed until the cat experienced hunger its physical efficiency would necessarily suffer, making it a less efficient predator. Hence, the predatory sequence is initiated immediately on the observation of movements in the environment that may be predictive of the presence of prey (Bradshaw et al, 2012). This has implications for human movements, especially if a family use hands or feet in early play with kittens (Cat Protection, 2017). The need to respond to any opportunity to predate means that a cat may initiate a hunting expedition immediately after a meal, but a well-fed cat may not hunt so regularly (as little as a quarter of the day), but it is likely to be more successful when it does hunt. A feral cat is likely to spend at least half of its day in hunting activity (Bradshaw et al, 2012).
Further implications of predatory activity on play is the nature of the cat's response to toys. Play most often occurs in short bursts, as the cat loses interest in the toy once it realises that the toy is not ‘real’. Play is likely to be sustained for longer periods if the toy is more life-like to the cat — hence, toys that appear attractive to owners are likely to be less popular than a simple feather or piece of fur. Play can also be enhanced by aiming for frequent, short sessions and the regular rotation of toys (Cat Protection, 2017). As the play drive in cats is primarily driven by the seeking emotion and the act of predation, play can be energetic and the cat can become highly emotionally aroused, creating the potential for frustration (and possible re-direction of aggressive behaviour on to other social stimuli) if games fail to end on an opportunity for consummation of a small treat (Ellis, 2016).
It has been noted that the early weaning of kittens (e.g. following the death of the mother cat) seems to bring forward the activity and efficiency of predation. In addition, hand rearing of orphan or sickly kittens has been associated with an increased incidence of frustration-related behaviours, such as aggression, on failure of the kitten to gain access to a desired resource (Warnes, 2017). These eventualities have considerable relevance regarding the safe handling of such kittens — both during rearing and within the new home.
Predation, communication and social relationships with other cats
Due to their predatory activity, it was initially thought that the cat's only requirement of communication was to indicate the boundaries of territory, and the cat's relative willingness for reproductive activity. But it is now known that the cat's capacity for communication and sociability, if developed appropriately, is more varied than originally thought (Ley, 2016a). The role of the feral queen is to protect her kittens until they are independent of her; as kittens are potential prey to many other animals (e.g. in UK hawks, owls and dogs) the feral queen will keep kittens carefully hidden for the first 4 weeks of their life and remains vigilant of their activity until they are sufficiently mature to be independent of her (from 7 weeks of age) (Deag et al, 2000). Such kittens inevitably fail to develop social relationships outside their experience of their mother and siblings. The need for successful predation alongside no evolutionary preparation for close social companionship or the capacity to share resources, places considerable constraints on both the kitten's sociability and the capacity to develop a range of social signalling (Deag, 2000). So, cats generally lack the capacity to develop a wide range of subtle facial or body language, they have no concept of ‘waiting their turn’ in a hierarchy, and also lack the capacity to diffuse social tensions to repair any breakdown in social relationships (Ley 2016b). Consequently, the cat's communication system relies heavily on olfactory signals, particularly via pheromones, allowing for inter-cat communication from a safe distance — preventing the need for cats to enter an area concurrently, reducing the potential for social friction, and preventing individual cats from attempting to predate an area where another cat has recently either eaten, or frightened off, the resident rodents (Ley, 2016a).
With such strong innate, genetic drives to live an asocial lifestyle, what chance does a kitten have of developing social flexibility with other cats?
Despite the above, cats are seen to live in social groups in many feline colonies throughout the world. Although some of these colonies appear quite large (as many as 50 cats), they usually consist of several smaller groups (maximum of 10 adults) that come together to access food as and when it is provided by the human population — at other times, the groups disperse into separate areas of the territory (Bradshaw et al, 2012). Such groups are all female and matriarchal, they are related females who are the produce of one, older, female cat. These cats assist each other with the birth and rearing of each other's kittens, guarding and suckling a shared pool of kittens while other female cats are hunting (Rochlitz, 2009). Although the female kittens remain within the group, males are discouraged once nearing sexual maturity and lead a tenuous existence on the edges of these societies, being met with intense aggression by females that they attempt to approach. However, it is clear that if these cats are co-existing within a social group, then communication must be required to maintain peaceful relationships. Consequently, these cats are seen to use their tails and limited facial and ear movements in communication; in addition, allo-rubbing and allo-grooming are used to create a group scent, that allows for social recognition and acceptance (Crowell-Davis et al, 2004). Consequently, it is possible, if born into a sociable group of cats, for kittens, particularly female kittens, to develop social skills that enable sociability with other cats to be maintained into adult relationships (Crowell-Davis, 2003). But such flexibility is highly dependent on social olfactory recognition, access to sufficient resources and the maintenance of a consistent olfactory profile within the environment (Cat Protection, 2017).
Genetic ‘preparedness’ — specific fears associated with the cat's evolutionary history
Enhancing a cat's sociability towards humans can be problematic (Figure 1). With no innate need for sociability, the cat is limited in its drive to seek out attention from its own or other species (Ellis, 2016). In addition, all species have a genetic preparedness to avoid other species that have an evolutionary significance to their survival. As the cat is relatively small it is potentially a meal for a range of larger predators, creating an innate anticipation of danger (anxiety) when in proximity to other animals. In addition to larger animals and birds of prey, pain, rapid stimulus change, sudden movements, loud noises and other intense sensory stimulation, as well as unfamiliar environmental and social situations, will all initiate preparatory arousal and a need to escape.
As a consequence of the above, it can be seen that the requisite to maintain competency at predatory skills can create considerable conflict between the behavioural repertoire that owners may desire (a sociable companion for humans and other household cats alike, offering little or no threat to local wildlife), and the cat's behavioural needs (predatory confidence from post weaning and hence reduced social tolerance of potential competitors for resources).
Further recognised genetic traits affecting sociability in kittens
It has been suggested that some male cats carry a male boldness gene (McCune, 1995). Although this gene does not directly drive enhanced sociability in offspring, it enhances a drive to investigate novel situations, leaving greater opportunities for affected kittens to learn positive associations with the social and environmental stimuli to which they are exposed (Figure 2). Kittens have also been shown to have different personalities regarding their willingness to approach humans (friendly or unfriendly), and to engage in play — offering further positive learning opportunities (Bradshaw 2012). These genetic traits seem well developed by 8 weeks of age and hence any attempts to overcome them need to be made via the correct type of interventions in selecting appropriate breeding stock and providing a suitable environment while the kitten is with the breeder (Mendle and Harcourt, 2000). In addition, through the action of epigenetics, kittens born to cats that have had fear inducing encounters with specific stimuli (including humans) can inherit that fear (Warnes, 2017). Hence, ensuring that hobby, show and professional breeders use the correct genetic stock (relaxed and showing sociability to other cats and humans) is an important starting point in producing kittens that are relaxed and emotionally resilient within a domestic home.
The limitations on behaviour associated with the cat's emotional flexibility
Surviving in ‘the wild’, or as a companion animal in a domestic world, requires the activation of emotions, emotions that are not ‘feelings’, but that are neurochemical systems that mediate instinctual emotional arousal within the cat. It is these emotions that initiate arousal, a stress response and that dictate the subsequent behaviour of an animal (Mills, 2016). Cats can experience eight emotional systems (Karagiannis and Heath, 2016):
Without human intervention, how much behavioural flexibility can we expect a cat to offer?
An individual cat's behaviour will be dependent on its genetic blueprint (including its ethology and innate behavioural responses associated with its emotional systems), in addition to its life experiences (the situations that it has encountered and the subsequent learning that has occurred associated with those encounters) (Zulch, 2017). The environment also produces epigenetic effects — an animal may be born with a specific genetic blueprint, but negative environmental experience adds to this to create a new genetic makeup, which can then be handed on to future generations (Zulch, 2017). The specific behaviours observed in the cat at any moment will be dependent on these aforementioned conditions and the current environment in which the cat finds itself. Any of these factors may form barriers to the cat's capacity to offer the level of behavioural flexibility that its owners may expect of it.
The 8 week of age ‘cut off point’ for the mediation of many genetic trends towards sociability further emphasises the need for thorough pre 7 week socialisation and environmental referencing to overcome potential genetic and epigenetic barriers to learning, sociability and resilience to the environment (Denenberg, 2018).
Conclusion
Although the environment experienced by the queen throughout pregnancy and the kitten's post-birth environment will be highly influential on the level of expression of genetic influences, the starting point for producing a kitten with the potential to develop resilience to, and a consequent capacity to cope within, the complexity of a domestic home, is the selection of the correct parents. This requires breeders — both professional and hobbyist — to place less emphasis on the potential aesthetic appearance of the kitten, but instead to concentrate on its future physical and emotional health. In short, selecting only parents with proven capacity to remain physically healthy and emotionally relaxed within a multi-species, domestic environment. Such a momentous change in breeder attitude will require the gentle but consistent influence of the veterinary profession, both in their influencing of breeders and their education of members of the public, ensuring that they are aware of what to expect from a kitten breeder. With a concerted effort, the welfare of the domestic cat and the capacity of kittens to develop into confident cats that are resilient to the complexity encountered while co-existing with human families, can be enhanced.