This page provides references regarding paternal influences on feline temperament. It is considered that tomcats contribute greatly to the temperament of kittens. This is stated on a number of websites, but without references to source studies. It has been shown in studies that bold, outgoing fathers produce bold, outgoing kittens and this boldness means the kittens are easier to socialise with humans. Timid fathers produce timid kittens and these require more patience and persistence to overcome the inherited timidity. Inbetween "bold" and "timid" is a whole spectrum of personalities. The genetic influence of the mother on other aspects of the kittens' personalities is harder to determine since they mimic her behaviour and this can alter inherited traits.

Breeders have long believed that the sire greatly influences the personalities and temperaments of kittens. A good-tempered, friendly stud cat tended to produce good tempered, friendly kittens. For many years this remained anecdotal and there were no statistics to back it up. Researchers raising colonies of laboratory cats had also noticed differences in the ease with which kittens of different parents could be handled. The differences in personality were evident even though all the kittens were raised under identical conditions. By choosing the right parents, they could breed cats more amenable to the sort of handling needed for experimentation. The fact that the laboratory breeding conditions remained the same meant that something other than environment affected the kittens' friendliness towards people.

To test this theory, Sandra McCune an animal behavior expert at Waltham Centre for Pet Nutrition, performed an experiment at Cambridge University to see what effect the father's temperament had on his kittens. She separated kittens into two groups. Each of the groups included litters of kittens whose fathers were friendly toward people and litters whose fathers were unfriendly or standoffish. The kittens never met their fathers, so the fathers' only effect was genetic. All of the kittens remained with their mothers and littermates. Between the age of 2 weeks and 12 weeks, half the kittens were handled by a person daily for a total of 5 hours a week. The other half were only exposed to people during feeding and daily cleaning of their pens. When the kittens were 12 months old, they were all tested to see how they reacted to meeting people, being handled by people and encountering strange objects. The results showed that, for the cats in the experiment, the effect of early handling was about equal to the effect of having a friendly father. Handled cats with unfriendly fathers and unhandled cats with friendly fathers were both about as likely to hiss when a familiar person approached them. However, they were both less likely to hiss than the unhandled cats whose fathers were unfriendly (whether handled kittens from friendly fathers were additionally laid back wasn't reported in the various articles citing this study). The more friendly cats in McCune's study were generally bolder (less fearful) and more willing to approach and investigate a strange object. This suggests that friendliness is all about being less fearful and linked to the production of stress hormones.

Although the kittens had never met nor observed their fathers, McCune found that the friendliest kittens were those from the friendly father. In fact, in each litter the kittens exhibited the same type of temperament as the father even though they had never met him. The only way seems possible is if their behaviour was inherited genetically from their father. However, while a kitten inherits aspects of its father's temperament, that won't necessarily contribute much to to its adult personality. The Cambridge University study suggests that genetics plays a part in early development, but the personality is shaped throughout its life by many other factors including socialisation and environment. Reference: S McCune (?1998), The Impact of Paternity and Early Socialization on the Development of Cats' Behaviour to People and Novel Objects. Applied Animal Behaviour Science.

It is still not clear whether inherited (genetic) friendliness is more strongly influenced by the father than by the mother. Although another study reported a maternal influence, it wasn't possible to work out whether the effect was genetic or learned. To test whether kittens inherit personality traits from the mother, or whether they learn traits from her, requires the kittens of a fearful mother to be fostered from birth onto a friendly mother. Kittens from a friendly mother also be fostered onto a fearful mother. To reduce paternal influence, both set of kittens must have the same father. I don't know whether this experiment has yet been done (either deliberately or in cat shelter/breeder conditions where kittens must sometimes be fostered).

"Friendly mother and father cats tend to have friendly kittens, and this suggests that inherited factors play a part also. Friendly mothers could, in theory, influence their kittens in two distinct ways. First, they could pass on genes which help their kittens to socialize well with people. Second, they could influence their kittens' interactions with people directly. Kittens probably learn a great deal by copying their mother's lead, and if she is nervous or frightened when interacting with people, they may simply copy her. However, it is perfectly simple to arrange for a tom cat not to even see his kittens; since they cannot then copy his behaviour, he can only influence them through his genes. This lack of ambiguity is the reason why cat biologists have concentrated on the inheritance of behavioural traits from the father, rather than the mother. It has now been demonstrated several times that tom cats tend to produce kittens that are as friendly or unfriendly as they are themselves. Mothers must also tend to produce kittens that are as friendly or unfriendly as they are, although they will also influence their kittens' friendliness directly, through their own behaviour."
Dr John Bradshaw, The True Nature of the Cat

"Independent observers rated adult female cats and their offspring at two research colonies on the trait 'friendliness to people' [...]Turner et al (1986) found that at both colonies the friendly ranked offspring were disproportionately distributed between one of two fathers, although the offspring had never come into contact with their fathers at either colony. Only in the colony where the various mothers had lower coefficients of relatedness (greater genetic variability) could they find a significant mother-effect on this trait, which of course, could be modificatory and/or genetic. The authors stated that they did not find evidence for direct inheritance of the behaviour involved [...] Nevertheless their results demonstrate that offspring from a particular male are reliably different from those of another particular male; variability on the trait 'friendliness to humans' is at least partly explained by paternity."
Dennis C Turner & Patrick Bateson, The Domestic Cat, The Biology of its Behaviour
Based on DC Turner, J Feaver, M Mendl & P Bateson (1986) Variations in Domestic Cat Behaviour Towards Humans; A Paternal Effect (printed in Animal Behaviour, Vol 34)

Kittens reared identically can nevertheless have strikingly different personalities, and it is likely that many such differences are caused by genetics. It should be remembered that genes cannot influence behaviour directly, only via the proteins that they code for, and therefore that the inheritance of behaviour is much more complex than the inheritance of, for example, coat or eye colour . A small number of controlled breeding experiments have been carried out in which the behaviour of the sire has been related to the behaviour of its offspring. This is not to say that kittens do not inherit behavioural traits equally from mother and father; it is simply experimentally expedient to examine paternal genetics, since the sire can be excluded from having any direct contact with his kittens, whereas the mother cannot. The trait that has been examined is that of 'Boldness', which influences whether kittens are more or less ready to approach novel objects and people, depending upon the extent to which their father exhibits that trait; ie, all other factors being equal, bold fathers tend to produce bold kittens, timid fathers tend to produce timid kittens.
Dr John Bradshaw, Cat Personalities and Their Origins