Social Behaviour of Cats
It is a common belief that the dog is a social animal while the cat is an unsocial, selfish animal that pre- fersprefers to walk on its own. This is only partially correct and applies best to wild-living cats in areas with a low-density cat population. If cats were unable to live socially, they would not be successful as com- panioncompanion animals. In fact, all animals are selfish to some extent. When they co-operate in a group, it is because the benefits they receive outweigh the costs. This chapter considers how cats can live in a com- munitycommunity of cats – outdoors or in the home. The English ethologist David W. Macdonald and co- workers have conducted a particularly nice, long- termlongterm study of cats living in social groups in the English countryside. Both this and other research helps us to understand how owned cats respond to others they meet outdoors and how it is possible to have more than one cat in the same household with- outwithout frequent aggression between them. In Chapter 12, you will learn how cats adapt to a social life with people to the benefit of both parties.
Basics of Social Behaviour
We must first explain three ethological concepts: terri- tory,territory, home range and personal space, to better under- standunderstand the dynamics of cat social behaviour. These terms apply to animals in general, including cats.
Territory
Some animals establish and live within a territory. A territory is an area used almost exclusively by a particular animal or social group and defended against intruders of the same species. The territory contains all the necessary resources for living, such as food and water, and safe locations for resting and giving birth to offspring. Territories usually don’t overlap, and territory holders regularly patrol their territorial boundaries to check that no intrud- ersintruders are trespassing or watch their territory from a lookout (Fig. 5.1). They may also deposit scent marks along the boundaries warning others to stay out. A territory is vigorously defended, and any foreigners who enter the territory are chased away. Territory holders usually succeed in this defence. They have the most to lose and are familiar with the area, which boosts their self-confidence. Confidence declines with increasing distance from their own territory and great boldness is needed to enter the territory of another.
Cats can be territorial, but they do not generally defend the whole area in which they roam or spe- cificallyspecifically mark territorial boundaries. Instead, they deposit scent marks in places they habitually use, such as urination and defecation sites, sleeping sites and along pathways (see Chapter 4). In areas with a low cat population, free-roaming cats sometimes have non-overlapping living areas, which do not need to be defended as territories. In areas with a higher density of cats, the residents may defend a small territory but share more peripheral hunting grounds with others. At even higher densities, they tolerate the presence of others throughout their liv- ingliving area but may defend specific resources such as a food bowl or nest site. This is called local resource defence. Intact, free-roaming tomcats move over larger distances than do females, cover- ingcovering an area that can include the living areas of multiple females. They may defend a small territory during winter but spend too much time away to defend one during the breeding season. Then, they engage in local resource defence, with the resource in this case being females in heat.
Home range
A home range is the total area used by an animal over the course of an entire year, regardless of whether it is a defended area or not. For owned cats that are allowed outdoors, this is not just their owner’s home but also includes the whole outdoor area over which they roam. For cats that share parts of their home range, the home range is larger than their territory. Cats that only show local resource defence have a home range without a ter- ritory;territory; that is, they defend resources in their imme- diateimmediate vicinity such as the food they are eating or the place where they are currently resting.
Rather than being a particular shape or size, a cat’s home range may be a somewhat fragmented space, including areas that are used only during part of the year. For example, tomcats with outdoor access will use more of their home range during the breeding season than in winter. In contrast, in the first few weeks after giving birth, a mother cat will use less of her home range as she needs to return to the nest regularly and frequently to nurse the kit- tens.kittens. An outdoor cat’s home range contains a net- worknetwork of trails leading to good hunting areas and several safe resting spots. Cats do not always go back to a single location to rest. It is more efficient to rest near where they are currently hunting. Even mother cats take naps away from their kittens, especially once the kittens are a few weeks old. An owned cat probably does not imagine that its owner is becoming worried when its return to the house is delayed because it decided to stop for a nap.
The core area of a home range is the area where an animal spends the most time, what we might consider ‘home’. This is the area most likely to be defended as a territory. For breeding females, this area is centred on the concealed nest site where they keep their kittens. The core area will usually include concealed resting places, areas with loose soil or litter used for elimination, safe places to sunbathe, lookouts for monitoring the surround- ingsurrounding area and access to some food and water. Cats living in social groups have overlapping home ranges with a common group core area that they may defend from non-group members. For owned cats, the apartment or house and garden is their core area, shared with humans and any other cats in the household.
Personal space
Most animals prefer to maintain a certain mini- mumminimum distance from other individuals, termed an inter-individual distance. This results in a personal space around the individual, often oval in shape and largest in front of the head. The personal space is like a mobile mini-territory around the animal. If another enters this personal space, the individual will feel uncomfortable and may retreat or threaten the other, thereby freeing up this buffer zone. In humans, this space is typically about 0.5–1 metre, explaining why many do not feel comfortable close to strangers on a crowded train or bus. In cats, a confident individual is likely to send threatening signals on the close approach of an intruder, caus- ingcausing the intruder to steer clear, whereas an anxious individual would rather move away itself than risk conflict. If kept in a confined area where they are unable to regulate the distance between them, cats may live in a state of heightened social stress.
A personal space does not have fixed dimen- sions.dimensions. Its size depends heavily on who is nearby and what they are doing. With social partners and off- spring, the inter-individual distance may well be zero when resting without causing any problem. Cats who do not have a particularly close relation- shiprelationship with another cat or a person prefer to stay at least 1–3 metres away. They may attack by leaping upon another cat or your hand if it comes closer than this. When hunting outdoors, a cat will usu- allyusually keep many metres away from unfamiliar cats, not only avoiding direct attacks but also avoiding threat signals. In a multi-cat house with cats that tolerate each other but who are not best friends, the cats are usually careful to maintain an inter-individual distance of at least one metre.
Do cats prefer a single or a social life?
The biologist and author Desmond Morris once stated: ‘A lonely dog is a miserable, unhappy creature. A lonely cat is often just relieved to be left in peace.’ This implies that adult cats prefer a solitary life over group living. In fact, for free-living cats, the local ecological conditions are crucial in influ- encinginfluencing which option a cat chooses. In areas with a high population density of cats and variability in the distribution of prey – that is, having some areas with an abundance of prey and other areas where prey animals are scarce – cats are likely to be found living with others in a social group. The group can collaborate on maintaining a common group territory and keeping other cats away from their rich hunting areas. David Macdonald showed that such group-living cats tend to be healthier than the soli- tarysolitary cats that are excluded from such areas and forced to live in marginal areas with limited food. On the other hand, if the density of cats is low and they are hunting small prey that are relatively evenly spread out, most cats prefer to live apart from other adult cats. In dense urban environments containing many cats, they hardly have a choice. They must try to adapt to the close proximity of other cats. Flexibility is a keyword for cat social behaviour.
When people feed a cat and provide it with a place to live, the cat may settle down and establish social contact with the people living in the house- hold.household. If socialized to people as a kitten, it will continue to seek care from people in adulthood. When let outdoors, however, the cat will behave similarly to free-living cats.
Traffic-handling among cats
When a well-fed owned cat uses an outdoor area where cats from neighbouring households are present, their scent marks regulate the ‘cat traffic’. These do not prevent others from using the same area but minimize face-to-face encounters. Cats can be quite careful to avoid each other, and they use both sight and smell to check when the coast is clear. Since the scent marks inform them about who was at a certain place and how long ago (see Chapter 4), they can establish a kind of shift schedule for the use of a popular area. If Jasper finds that Oliver typically hunts in a particular area in the early morning, Jasper may hunt there in the evening. If Luna finds that Bella uses a particular resting place in the afternoon, she can use the same place in the morning. In this way, they avoid conflict. This is the cat form of a shared economy.
If two cats should find themselves walking towards each other along the same path, it is nor- malnormal for one to sit down and wait for the other to pass. There is no reason to attack another that makes no threat. If two more competitive cats meet, maybe at short distance, they do not fight for the right to use the path but instead sit down and threaten each other by staring. Eventually one will give up and carefully take a different direction. Perhaps it is safest to return from whence it came.
Indoors, it is common for group-living cats to respect each other’s first right to a particular place. If a cat arrives first at a food bowl and there is no room for additional cats, a latecomer is likely to wait until the first one has finished eating. If a cat has occupied a resting place, another cat will usu- allyusually not chase it away but, instead, find another place to sleep. This ‘courtesy’ depends upon the cats perceiving that resources are plentiful and that they can get enough of what they want (see Chapter 11).
Rank order
To a certain extent, dominance relationships between cats are decided based on body size, which is in turn influenced by age and sex. If body sizes are very different, the difference in competitive ability is obvious and there is no need for a competition to decide who is dominant. Thus, adult males will usually have a higher rank than adult females based on their larger body size. It is the individuals who are close to each other in apparent competitive ability that show the most conflict with each other. Once the ranks have been settled, though, it is rare for them to change.
Leyhausen found that it is particularly in very dense populations of adult cats that an absolute hierarchy can emerge. There may be too many cats for social regulation based solely on relative ranks. More dominant cats regularly exhibit threatening signals that remind others of their priority of access to resources. This can happen in laboratory col- oniescolonies of cats or when there are many cats in a house- hold.household. A simple type of absolute rank order can be seen within litters of kittens, where certain kittens have priority of access to the milkiest teats. These kittens were perhaps the biggest and boldest at birth, and with access to the best teats they grow faster. This is also termed a teat order.
Since female and male cats mostly live separately in nature, we shall describe their social behaviour separately.
The Female Cat’s Social Behaviour
Adult females can have a home range varying in size from a quarter of an acre to about 500 acres (2 km2). Food availability plays the main role in determining the size of the area needed by an adult female cat. When nursing kittens, this is especially important. As the kittens grow bigger and demand more milk, she will need to find two or three times as much food as usual. It is common that the female’s home range overlaps with others, even though she is not living in a group. This is particu- larlyparticularly true in an area rich in small prey scattered in unpredictable locations where it is not practical to defend the whole area from intrusions by others.
A female cat living singly can be quite territorial; that is, defending her territory against other cats of both sexes. But when she is in heat, she may toler- atetolerate males nearby. She is most aggressive towards other cats when she has kittens. This is partly due to the need to defend her kittens and partly to the need for a larger hunting area when nursing her increasingly demanding growing kittens.
Cats living in groups
The density of cats living outdoors can range from less than 300 m2 to over 1 km2 per cat. This vari- ationvariation results in differences in social organization. The prerequisite for cats to be able to form a social group is a concentrated food source. This is often associ- atedassociated with human activity – people feeding free-free roaming cats, cats exploiting landfill or rubbish bins, and cats on farms where they find an abundance of small rodents or steal food intended for the farm animals. Mink farms are popular with cats, as the nutritional needs of mink and cats are very similar.
An accumulation of cats in one area does not always constitute a social group. Instead, it is pos- siblepossible to talk about a colony of cats that stays in the same place for the same reason, but without real co-operation. In such cases, this is considered an aggregation of single cats rather than a social group. Such cats frequently snarl if they get too close to one another while dining on scavenged food.
The most basic social unit in cats is a female cat with her offspring. This is termed a core group. It does not include the father of the kittens, who may be far away and the father of offspring in several such core groups. Larger social groups of cats usu- allyusually consist of several female cats with their off- spring, that is several core groups. The adult female group members are called central females. Such groups can include juvenile daughters and sons of the adult females in the group. In addition, a few adult tomcats may be associated with the group. These have contact with the adult females espe- ciallyespecially when mating during the breeding season, but otherwise stay on their own. Usually, these males are not closely related to the adult females, as adult males emigrate away from the area where they were born, a mechanism that reduces the likelihood of inbreeding. There are rarely more than ten indi- vidualsindividuals in a social group, but groups of more than 50 cats may occur if there is a large enough, pre- dictablepredictable food supply, as reported by Macdonald and colleagues in England. In other regions, colo- niescolonies with several dozen free-living cats are found in cities with large populations of homeless cats.
The central females of a social group may attack intruders of both sexes. Apart from this central group and their young offspring, other females and males live alone. These are called peripheral cats when living on the periphery of a social group, usu- allyusually under harsher living conditions. Peripheral cats may, nevertheless, hunt for prey within the core area used by cats in the social group, so this is not a watertight territory where intruders are completely shut out. The social dynamics can vary widely between such groups, related to the group size, ecological factors and personality characteristics of the individuals within the group. Small colonies of cats in the countryside can consist of two or three core groups, where the cats have more contact with those within their own core group than with cats from other core groups.
Collaboration on kitten care
Females living in a social group can be very friendly towards one another. In naturally forming groups, they have usually remained in the group from birth, and rarely move over to another group. Since they hunt alone, their home range sizes can differ, but the group has a common core area where they give birth to kittens and where their main food sources can be found. Here they can have a common nest and help each other with the care of the kittens. They tend to have synchronized heat cycles and give birth around the same time, and their kittens may have the same father or fathers. David Macdonald has observed that a female cat can help another female by biting the umbilical cord of a newborn kitten. It is not unusual for them to nurse each other’s kittens. This is called communal nurs- ingnursing. Sometimes a female brings prey to another nursing cat. Nevertheless, the females regularly stay closer to their own kittens than to those of the other cats. It appears that they recognize and pref- erentiallypreferentially care for their own offspring.
Female cats living in social groups can produce larger litter sizes than solitary females. In Macdonald’s study of a large colony of farm cats, females that co-operated in kitten care and joined forces to defend food resources had lower offspring mortality than those living alone. Communal nurs- ingnursing is a type of helper system, or what we could call aunting behaviour among humans. The females in cat social groups are usually closely related – moth- ers,related–mothers, daughters, sisters and half-sisters, and perhaps grandmothers. Therefore, in evolutionary terms, such helping also benefits those who help. Genetically, a female cat is 50% related to her full sister or mother and 25% related to her half-sister. If she helps her full sister to produce two more weaned offspring than she would have been able raise by herself, the helper will have contributed as many of her own genes to the next generation as if she had weaned one kitten herself. This phenomenon is termed kin selection and is thought to play an important role in the evolution of social behaviour.
The Male Cat’s Social Behaviour
The home ranges of intact male cats are, on aver- age,average, 3.5 times larger than those of females. In extreme cases they can reach up to 2000 acres, or 8 km2. More commonly, a male’s rural home range area is 2–3 km2. The males obviously do not need such a large area to catch food. The reason for roaming over such a large area is the tomcat’s urge to seek out females in heat. Therefore, a tomcat’s home range often overlaps with the core areas of several females. At the same time, this means that they also overlap with the home ranges of other males. Outside the mating season, however, the overlap can be small. High-ranking tomcats usually have larger home ranges than males with lower ranks, probably because they can roam more freely without being threatened by other males. In more densely populated areas, both females and males have smaller home ranges. These cats usually receive food from humans, and uncastrated males can have good access to fertile females nearby. However, when many female cats are spayed or kept indoors, it becomes harder for tomcats to find females accessible for mating.
When male cats quarrel
Kittens are usually tolerated by adult males. When young males reach around 10–12 months of age, older males can invite them to battle using special call sounds. Initially, the fights are trivial and usu- allyusually playful. Only in the second year of life does male rivalry become more serious. Then the young tomcat must show his competitive ability. After sniffing each other, both males show aggressive signals, where the body posture, ear position and sounds inform the other one how bold he is cur- rentlycurrently feeling. Sometimes it seems that the competi- tioncompetition is all about making the largest yowling noise. If two males are quite evenly matched and neither exhibits pronounced defensive signals, there may eventually be a fight. This is a last resort, however. The cats can easily incur bad bite injuries, and they try to win the contest using offensive threat signals. Therefore, we should put up with the loud sounds of competing tomcats that wake us from our nightly slumber during early spring.
When one of the males finally accepts the domi- nancedominance of the other, he will show his defensive atti- tudeattitude by crouching down, hissing and maybe lifting his paw if the opponent gets too close. Cats do not show submission like dogs, exposing their vulner- ablevulnerable neck or belly. As noted in Chapter 4, a defen- sivedefensive cat informs his opponent that he will defend himself if attacked. Usually, the dominant male will accept such signals and end the dispute. At subse- quentsubsequent meetings, the conflicts will become shorter. Both now, and later, the dominant male will urine mark, and scratch and rub against tree trunks and other prominent objects. These actions send visual signals of dominance, and the scent marks provide a reminder.
Among lions, a small coalition of adult males lives together with the lionesses and their offspring continuously until, after a few years, they are chased away by a new coalition of younger, stronger male lions. The main difference in free- living cats is that males generally live alone rather than within the female group. Unlike lions, they do not need to co-operate during hunting because their prey is much smaller and can be caught by a single individual. We shall say more about this in Chapter 6. They also do not need to co-operate to gain access to females. Not surprisingly, then, tom- cats do not appear to form co-operative alliances. In dense populations, adult males are rarely friendly towards one another. However, where they live more spaced out, adult males that have clarified their dominance relationships can coexist peace- fullypeacefully and share overlapping home ranges. The most dominant males are rarely tyrants, although bully- ingbullying may occasionally occur depending on the indi- vidualindividual personalities involved.
What is the function of conflicts between males?
The most aggressive tomcat rarely has priority of access to important resources such as food and mating of females. Males can be surprisingly toler- anttolerant of one another. A cat that eats is rarely dis- turbeddisturbed by a more dominant cat. The last one waits his turn, at least so long as there is enough food for all. In the same way, the ‘first come, first served’ rule may apply to popular resting places as well as to the opportunity to mate with a female cat. The latter is more likely in larger than smaller cat col- onies.colonies. In larger colonies it is too difficult for one dominant male to chase away all other males. The queuing system means several males can mate with the same female, and she can give birth to a litter where the kittens have different fathers. Since all these males can be fathers, this probably reduces the risk of infanticide of young kittens by males, unlike in lions.
In small colonies, it is not unusual for one tomcat to be the father of almost all kittens born. In this case, a dominant tomcat manages to threaten other males to stay at a good distance from female cats in heat. However, the female cat herself decides whether she wants to mate with a particular male or not. She will not necessarily accept the most dominant male cat. As with some other mammals, and birds, if you had excellent reproductive success during the last season, why take the risk of substi- tutingsubstituting your partner? ‘Never change a winning team’ can be a good rule for animals, too. Bjarne has even known a wonderful and huge male cat that was rather lazy and not very interested in courting females. Instead, the females were queuing up to solicit his attention.
Perhaps the most important reason why male cats fight is related to the struggle for access to a habitat rich in food resources. A young male cat who is clearly lower-ranking than his neighbours will often emigrate from the area and settle in a less favourable area, with less food and few females. Here he can live in relative peace until he becomes older and stronger, and more likely to succeed in competition with other males. This may be the reason why some two- to three-year-old males sud- denlysuddenly disappear from home (see Chapter 7). Even though they have had a good relationship with their owners, competition from other males encountered in the neighbourhood may have led them to seek a new living area. At this age, it is natural for male cats to leave the social group of their mother. Biologically, this is an important mechanism for preventing inbreeding.
The male cat can be a good father
It is a common belief that male cats may be danger- ousdangerous to small kittens. Occasionally, a tomcat may kill kittens he comes across. Perhaps he considers them as regular prey. In lions, males can kill cubs that are not their own offspring, leading the lion- esseslionesses to come into heat more quickly. The males can then mate with these lionesses and father off- spring themselves. It is possible that such a repro- ductionreproduction strategy may also be found in some domestic cats, but it appears to be rare.
In Norway, there are many stories about male cats who gave care to kittens. In Trondheim, a large male cat carried, in his mouth, a kitten that had been hit by a car. Unfortunately, the kitten had to be euthanized, but the male did what he could. In another case in Trondheim, a homeless female cat was shot. Her young kittens, who were born out- doors,outdoors, were fed by a tomcat. He collected food and brought it to the kittens. At Nes, in Hedmark county, on the farm where Bjarne was born, a female died some weeks after giving birth to kittens in the barn. The resident tomcat, who might have been their father, carried the kittens, one by one, from the barn into the kitchen of the farmhouse. He knew that food was available there. Another story from Trondheim is about a cat family where the cat mother and her offspring were killed. It turned out that one of the kittens had escaped and was hiding outdoors. The tomcat took food in his mouth and ran outdoors, where he was thought to be giving it to the kitten. Eventually the kitten became so sick and cold that she entered the house. Here she was cared for and cleaned by the tomcat. It was thought that the tomcat was probably the kitten’s father. Much later, when the kitten had her own kittens in a completely different home, far away, one of the kittens looked very similar to this male, suggesting that he was the kitten’s grandfather.
In the 1980s, in the research cattery of the University of Trondheim, Bjarne saw that some male cats were particularly adept at taking care of kittens. After the kittens were weaned and separated from their mothers, they were placed in a separate room. Here an old male was used as a ‘kindergar- tenkindergarten teacher’. He carefully licked the kittens, and it was obvious that they appreciated his presence.
Such stories indicate that there are relicts of paternal instinct in domestic cats. This is another sign of their descent from the African wildcat, Felis lybica (see Chapter 1). In this species, the male and female sometimes live together in monogamy. In such cases, the female is probably dependent on the male helping her to provide enough food to raise kittens in the barren semi- desertssemideserts where they live.
Castrated male cats
A high rate of neutering is practised in many coun- tries.countries. For example, in Norway, about 85% of owned male cats are castrated, or sometimes chemically sterilized, especially those living in densely populated areas. These males do not have the same motivation to compete with others as seen in intact males. Rather, they may live in social groups with females and other castrated males and, like females, co-operate to chase away intruders from the group’s core area. When a castrated male seems to be bolder within its territory than else- where,elsewhere, this he a sign that he has more to defend in that area.
Multiple Cats in the Same Residence
Many people are unsure whether it is possible to have two cats in an apartment, especially if they have one cat already and now would like an addi- tionaladditional cat. Will they become comrades or feud for evermore? There are large individual differences in social behaviour among cats. This has a lot to do with the personalities of the different cats, and whether they will be compatible can be unpre- dictable.unpredictable. A cat may accept one newcomer but be aggressive towards another. Often, it is more suc- cessfulsuccessful to keep a female and a male together rather than two females, unless the females are closely related (e.g. sisters or mother and daugh- ter)daughter) or the newcomer is a kitten. In an American study of 60 homes with two neutered indoor cats, two male cats were closer to each other, on aver- age,average, than two females or one female and one male. Aggression between the cats was most frequent during the first two years and became less fre- quentfrequent the longer the cats lived together. Another study indicated that, in half of the cases, the new- comernewcomer was accepted before one month has passed. In England, the ethologist John Bradshaw showed that two adult cats from the same litter spent more time together than two cats from different litters did. Littermates more often ate together and groomed each other’s fur. If you wish to have two cats, it is therefore a good idea to obtain two from the same litter.
People with four cats in their household often believe that they have one social group consisting of four cats. They might instead have four cats that would rather live alone. In such cases, the cats must establish a kind of balance of power, staying by themselves and finding ways to avoid provoking the other cats. However, many people have mul- tiplemultiple cats living together in harmony. Like in nature, the most important means for achieving this is that the cats do not have to compete for resources. There must be enough food for everyone, with a separate food bowl and litter tray for each cat, and possibly extra ones. There must be plenty of resting places. Finally, yet importantly, each cat must get the same amount of friendly contact and petting by people in the household.
It is difficult to predict the outcome when intro- ducingintroducing a new cat. The easiest advice is just to try. If you are unsure how it will be received by your existing cat, ask for a two- to four-week trial period from the seller with the option to return the cat if the introduction is unsuccessful. A person who is selling or giving away a cat should take an interest in ensuring that it will thrive in its new home.
When the new cat arrives it is normal that the two cats will initially want to stay apart. The exist- ingexisting cat has something to defend and is likely to hiss at the intruder if it comes too close. The new- comer feels insecure in the unfamiliar environ- ment.environment. It is best to keep the newcomer in a separate room (such as the bathroom) for the first few days. Once it is relaxed in that room, eating well and willing to play with you, you can open the door. By then, the existing cat has also got more used to the smell and sound of the new one. Leave the new cat’s food bowl and litterbox in the original room (the bathroom in this example) for another week or more until both cats are comfortable being together in the same room. Do not expect them to become friends in the first two weeks, even if some cats become friendly more quickly. Make sure that there are separate places for them to retreat to. Do not force them to come closer together than they are comfortable with. Playing with each cat using a toy dangling from a wand may be helpful in plac- ingplacing both in a playful mood and encouraging them to come closer to each other. Eventually, the cats should accept each other, but it takes time, so be patient. They may never do so completely. In that case, the best you can hope for is that they will respect each other without frequent threats or fights, or one always feeling it must run away if the other is around. If they share space through mutual avoidance, this is often acceptable to the cat owner.
A Cat and Dog Together
Many people find it easy to have both cats and dogs (Fig. 5.6). The Israeli ethologists Feuerstein and Terkel examined this systematically in 2007, with behavioural observations on dogs and cats kept together in 170 homes, and questionnaire responses from the owners. They concluded that both animal species were equally inclined to enter into a friendly relationship. This is easiest to achieve if you get the cat before the dog, so that the cat has the psychological advantage of established residence before the arrival of the, probably larger, dog. It is advantageous if the cat is younger than six months and the dog is younger than one year when they meet for the first time. The researchers found that dogs and cats living together largely under- stoodunderstood each other. The younger they are when they first meet, the easier they will learn to understand each other’s body language and avoid misunder- standings.misunderstandings. Further advice on introducing cats and dogs is given in Chapter 2.