THESIS: An Investigation Into Gender-Specific Fear Of People In Canines

By Hannah Walker

In this paper Hannah Walker investigates the gender-specific fear of humans that some dogs experience.

The entire paper is available to view below.

Although dogs in general do not show a bias towards one gender, it is often anecdotally-reported that dogs, particularly rescue dogs, more frequently show discomfort or hostility towards unfamiliar men than women. The dogs’ owners may assume that the cause of their dog’s fear or aggression around men must convey that the dog has had a negative experience with men in the past, especially particularly when the dog only fears specific types of men, such as those with beards, sticks or hats. However, fear of unfamiliar men is common amongst anxious dogs, even when there is no history of trauma or abuse. Due to differing attitudes and practices between the sexes, dogs of indeterminate backgrounds are statistically more likely to have had a negative experience with men than women. However, there are also many olfactory, visual, auditory, developmental, genetic and circumstantial reasons that can have significant influence on how dogs perceive people. All dogs and people are individuals and there are no steadfast rules dictating whether a dog will be more or less receptive towards a specific type of human, but gender-associated characteristics and past experience do have an effect. This thesis will explore the many different factors that can contribute to gender-specific fear of people in dogs.

Many people who work with or own dogs will be aware that they are more likely to show hostile or fearful behaviour towards an unfamiliar human if they are male than if they are female [Hennessy et al., 1997]. As would be expected, fear of men is particularly prevalent in dogs who have suffered from poor socialisation or development and as such, rescue dogs commonly display reactivity or avoidance behaviour towards male humans. Multiple studies of shelter dogs document that high proportions of kennelled rescue dogs are reluctant to approach or interact with men [Lore & Eisenberg, 1986] or show increased barking and aggressive behaviour towards men. Conversely, women more commonly induced more relaxed postures and behaviour in the same dogs [Wells & Hepper, 1998]. This trend is not exclusive to shelter and rescued dogs, however; a study conducted on working dogs found that most of the dogs who failed during the training and qualification processes did so due to fear of humans, which was almost always specific. Most of the failed dogs feared men, but others were specific to children or strangers. None of the dogs, however, had displayed specific fear towards women [Gunrow, 1995]. The dogs in the study had all been raised from puppies and, thus, efforts had been made to ensure their developmental environments were adequate. Therefore, although poor socialisation and development do influence the likelihood of the development of man-directed fear or aggression in dogs, it cannot be the only factor. This is unsurprising, considering that the domestic dog resulted from co-evolution with humans over thousands of years and, as a result, they are influenced by many different aspects of human behaviour [Payne et al., 2015]. Human understanding of the world through the eyes of the dog is still rather limited, but we have begun to scratch the surface now on the many visual, olfactory, auditory, instinctive and hormonal components that contribute to the way in which a dog perceives a person.

Although often forgotten from a human perspective, olfactory signals play a very significant role in canine interpretations. Dogs, like any species, will make decisions based on all of their senses if possible, but scents often take priority over other forms of information in canine brains. Anyone who has ever spent time with a dog will know how highly they value smells, especially the longer-muzzled breeds. Dogs not only gain information about each other through olfactory cues, their noses also equip them with incredible detective abilities. As scent-detecting dogs are able to find a missing person through indistinct trails of day-old scents, it would not be at all surprising if they also used their noses to shape their behaviour towards people they meet. Often a trigger of human embarrassment, it is well-known that dogs like to investigate unknown people by honing in on their genital area. Interestingly, this investigatory behaviour is less common when dogs greet familiar people, to whom they usually focus attention on the upper body, possibly reading more into behavioural and social signals [Filatre et al., 1991]. This is important to note, as it suggests that dogs may place more weight on scents, particularly the very gender-specific genital odours, when faced with a stranger and that this information may override any other signals that would be picked up by focussing attention on body language and actions. A previous study found that, even if behavioural and motion cues are controlled by asking both genders to perform identical behaviours, such as sitting perfectly still, dogs are still significantly more wary of the men [Lore & Eisenberg, 1986].

Regardless of their behaviour, posture, vocalisation and other consciously-controlled cues, humans unwittingly give away crucial details about their state, health, gender, environment, emotions and even genetics within their body odours [de Groot et al., 2017]. There are fundamental differences between the scents of male and female humans. Potency is the most obvious different, with men possessing much more active apocrine glands. These glands produce sweat rich in chemicals, particularly in response to fear states. Men also tend to have larger populations of naturally-ocurring bacteria present in these glands, exacerbating the smell [de Groot, 2015]. Therefore, men will smell much more potent through the nose of any receiver, especially a highly scent-sensitive dog and this scent is also harder for men to conceal. According to research, dogs appear to be significantly more attracted to the odours produced by women and also find it easier to distinguish between the odours of individual female humans, possibly due to the lower potency [Jezierski et al., 2012]. Dogs also react positively to the smell of familiar humans, the detection of which activates the reward centre in a dog’s brain, as opposed to unfamiliar controls [Berns et al., 2015]. Clearly, dogs can not only recognise the scent of familiar humans, they can also distinguish between and remember individual human scents, a skill which requires a significant degree of mastery, considering it crosses species barriers.

The chemicals produced by an individual’s body not only function to regulate their own physiology and behaviour, they can also have an effect on other members of the same species and, in some cases, other species too. Considering the superior sniffing ability of dogs and their co-evolution alongside humankind, they are well-equipped to detect certain chemicals emitted by a human’s body and can act upon this, whether consciously or otherwise. There is growing evidence to show how dogs and even humans are affected by cross-species chemical signalling. Except in forms of sexual signalling, states conveyed or transferred through scents tend to be negative, mostly related to anxiety, fear or aggression. Due to the ambiguity of social communication, and the ability of intelligent species to intentionally deceive others, it is evolutionarily advantageous for an individual to be able to detect potential threats through an unambiguous signal that is not under conscious control, such as body odour. Furthermore, as social animals are able to modify their behaviour independently of their internal state or transient emotions, it is also advantageous to survival if an individual’s brain will override this conflicting information in preference of basic olfactory cues. Thus, a dog is more likely to react upon chemical signals conveyed through scent when they are confronted with an unfamiliar or threatening situation or person than when they are in a familiar or relaxing environment [Mutic et al., 2016]. Chemical signals conveyed in scents are capable of causing emotional contagion, whereby an emotional change in one individual induces an unconscious and parallel emotional change in another. Consequently, if a person is feeling stressed, this could plausibly induce an analogous stress response in a proximal dog [de Groot et al., 2012]. Scents are important to consider when assessing canine fear of men for several reasons. Significantly, due to the stronger levels of testosterone, androstone and more potent sweat glands in men, the chemicals produced during stress or fear are much stronger in male humans than women. Furthermore, even in a relaxed state, a male human’s sweat and other bodily secretions will naturally contain higher concentrations of the chemicals that signify stress or fear [Sommerville & Broom, 2001]. In studies on humans, participants were reliably able to identify the smell of fear in male, but not female, sweat [de Groot, 2015]. If increased chemosignals in male odour can be detected by, relatively anosmic, humans, it is highly possible that canines, particularly anxious individuals, will show a heightened awareness to the scent information produced by men. In addition, testosterone, a hormone found in much higher concentrations in male humans, is a behavioural mediator and leads to increased aggression in the individual and others in his vicinity [Overall et al. 2001]. The fact that men possess stronger odours, release more signals of stress and have higher circulating testosterone than women, could significantly contribute to a dog’s greater wariness and reactivity towards men. This will be exacerbated when the dog is already feeling anxious and therefore more likely to evaluate an individual based on odour than other situational cues.

Recently, scientists have proven that chemosignals produced through scents can transfer across species barriers, particularly when the meaning behind the odour may entail negative consequences for the receiver. For example,, if humans are exposed to sweat rich in fear chemosignals, an emotional contagion response occurs, whereby the receiving humans display physiological signs of stress, despite no other cues being present [de Groot et al., 2012]. Female humans were most receptive to these cues and, when instructed to smell the testosterone and adrenaline-rich scent of fearful men, women possessed significantly increased cortisol levels than when sniffing a neutral control [Wyart et al., 2007]. This shows that the chemicals circulating in a human’s body during fearful states do not only affect that human’s behaviour, they also cause similar chemical responses in surrounding individuals. Further studies show evidence of these chemical responses crossing the species barrier. For instance, rodents display a significant stress response to the presence of male human odour. Chronic physiological and behavioural signs of severe stress can be detected in lab rats exposed to male lab workers, but never in rats only exposed to women. In this case, the rats seemed to develop chronic stress simply when their environment smells of men, regardless of their internal emotional state [Sorge et al., 2014]. Canine studies show more precise examples of cross-species chemosignalling. When exposed to the sweat of unfamiliar male humans in a fearful state, dogs have been found to respond with concurrent signs of stress, such as elevated heart rates, typical stress behaviours and avoidance. The dogs did not show this behaviour in response to the scent of happy, relaxed male humans [D’Aniello et al., 2017]. It can be deduced that sweat and other bodily secretions produced during a stressful experience have a significant and distinct scent that is not under conscious control. Thus, chemicals released by sweat glands act as a reliable indicator of threat and fear [Mujika-Parodi et al., 2009].

Clearly, there are significant differences between the strength and type of signals that males and female humans produce in times of stress. Men and women also differ in how they respond to their own stress and that of others. Stress in women is more likely to manifest a ‘tend and befriend’ response rather than the ‘fight or flight’ response generally displayed by men. When cortisol levels increase, women are more likely to adopt nurturing and peacemaking behaviours, thus reducing risk through emotional pacification. Conversely, men are more likely to aim to reduce risk through physical actions, either directing themselves towards or away from the stressor [Taylor et al., 2000]. This effect is partly mediated by testosterone, a hormone that promotes aggression and lowers inhibitive control, found in higher levels in male humans of all ages [Christiansen & Knussmann, 1987]. As aforementioned, hormones such as testosterone do not only affect the individual, but can also transfer to other people and species. One study that observed handlers and their dogs participating in a dog show gave evidence to support that dogs and handlers share emotional physiological states when in a high-arousal environments, with significant human gender bias. During the observed competition, male handlers and their dogs both displayed mirrored increases in their cortisol levels, so presumably experienced higher stress, whilst female handlers and their dogs showed no changes in cortisol. This may be due to the soothing, non-reactive behaviour and mindset that women are more likely to employ when under pressure [Butter et al., 2015]. Interestingly, this gender stress bias was also found by researchers visiting the homes of dogs and their owners. Both men and their dogs showed elevated cortisol levels 20 minutes after the researches arrived at the participants’ houses, whereas women and their dogs together showed no change in stress levels [Schober et al., 2015]. Data from this study could help to explain why dog bites are more commonly seen in dogs with exclusively male owners than any other family group [Reza et al., 2011]. In these cases, dogs are responding to the chemosignals produced by their familiar owners, perhaps in response to the pressure of being faced with a difficult task, in a stressful environment or feeling insecure [Mutic et al., 2016].

Due to integral physical and psychological differences, men and women do tend to conduct themselves differently around dogs. The physical power that most men naturally possess is bound to be recognised by dogs. Canines hold an unrivalled ability to interpret and respond to human signalling that outperforms any other species [Payne et al., 2015]. While a dog displaying fear or aggression towards men may have been affected by previous negative experiences with male humans, fearful dogs are also more likely to react to anything they interpret to be threatening. Men, with their larger bodies, deeper voices, more muscular and broader features, will inevitably tend to appear more imposing to an anxious dog [London, 2011]. The pitch of a man’s voice is also, on average, around 80hz lower than that of women – a frequency that dogs find harder to distinguish and hear over long distances, possibly making men sound more ambiguous [Koolhas et al., 1999]. Additionally, men and women do tend to use speech in significantly different ways. Around dogs, women talk for dramatically longer periods than men, on average, and initiate speech towards a dog much sooner than most men [Prato-Previde et al., 2006]. Studies show many dogs to find a silently approaching stranger far more intimidating than a gently, continuously vocalising stranger [Farago et al., 2010] so this may explain, in part, why unfamiliar males may evoke more aggression or avoidance behaviours in anxious dogs. Furthermore, the speech that women choose to direct to dogs is relatively unique. Men tend to speak less often, more sporadically and unexpectedly and in a louder tone [Briton & Hall, 1995], whereas women tend to use ‘motherese’, a term coined for the cooing, gentle and repetitive language type that mothers direct towards their infants. Motherese is a surprisingly critical tool used in the socialisation and soothing of children and plays a huge part in a child’s development, so it is easy to postulate how this type of speech will also have a soothing and socialising effect on dogs. In modern society, domestic dogs are almost synonymous with children in a family unit. Dogs show a very strong preference for, and initiate interactions towards, unknown people, especially women, when they are speaking in ‘motherese’, compared to people displaying silence or other forms of speech [Hastings, 2014]. Dogs are also more responsive and more likely to obey commands if conveyed through ‘motherese’, than to lower-frequency, louder commands [Topal et al., 2014]. However, men are, of course, able to alter their own behaviour, so this gender bias can be omitted, to a degree. Studies have found that if men talk in the same high-pitched, quiet and chatty ‘motherese’ that women instinctively use, men can be just as effective as women at reducing stress levels in dogs [Hennessy et al., 1998].

Posture is another factor in which men and women tend to differ significantly. One fascinating study found that, when viewing a simulated image of a silhouette of a man or woman shape in motion, people reported with outstanding reliability that the man was walking forward and the woman was walking away [Brooks et al., 2008]. This is probably a result of neurological and physical adaptations for survival. It is evolutionary advantageous for an individual to perceive the stronger, more threatening sex as approaching, even if they are actually walking away. This is because mistakenly viewing a, potentially more threatening, man as departing when they are actually approaching poses a higher risk than incorrectly assuming they are approaching when they are not. Evolutionarily speaking, it would be more advantageous to survival to be over-cautious towards a larger, more powerful human than under-cautious. The biological advantage of perceiving a woman as moving away, on the other hand, is possibly a trait evolved to protect children. If a child is more likely to assume the distance between their mother is increasing, they are more likely to remain close and follow the mother figure. The potential danger to a child of mistakenly assuming a women is approaching when they are actually moving away is far greater than assuming she is departing, as the child may continue to wander and consequently get lost. There is far less risk to a child to assume the woman is departing when she is approaching than the other way around. Therefore it is biologically advantageous to perceive more men as approaching and women as leaving. Although this study was exclusively conducted on humans, it is not implausible that the visual perceptive bias may also be present in dogs. They have, after all, co-evolved alongside humans and are incredibly perceptive to most of the conscious and unconscious cues humans use to communicate and transfer information. Perhaps, dogs will be more inclined to react with fear to the sight of a strange man in the distance than a strange woman because they, too, perceive the man as approaching even if he is not. ‘The approach’ of a human itself is a significant fear trigger in anxious dogs. Many dogs are more tolerant to the presence of a stranger if walked in parallel, but react to a direct approach. Additionally, dogs are significantly more likely to be fearful of or defensive against an individual if this individual is approaching in a threatening manner than if the same person was moving in a friendly way [Vas et al., 2007]. So, if the way in which a human approaches is clearly a factor to which that insecure or fearful dogs are hyper-aware, the greater perception of a man’s approach may contribute.

Individual humans vary in their perceptive abilities and, just like us, some dogs may also be more perceptive of subtle social cues than others. This may explain, to a degree, some of the discrepancies between dogs’ reactions to differently-gendered strangers. Considering humans alone, women tend to be significantly more aware of and able to interpret non-verbal social cues. This translates to canine communication to a degree and women are statistically more able to detect discomfort in a dog and to correctly decipher when it is unsafe to interact with a dog than men and children [Reisner & Shofer, 2008]. Additionally, during interactions with dogs, one study found that men are much more prone to sitting down on a seat or bending in order to stroke a dog, whereas women and children almost always crouch down to the floor and approach from to the dog’s level [Robinson, 1995]. This action itself may make the men seem more intimidating. A sitting posture can look very tense from certain perspectives; the rigidity of backs and legs that may appear as tension. The act of bending the torso, for instance to stroke a dog from above, is also known to evoke defensive reactions in dogs [Vas et al., 2005]. Most anxious dogs would prefer to be stroked from below, for instance on the chest or torso, rather than over their heads and so may prefer interacting with someone who has descended to their level. To summarise, crouching down to the ground and speaking softly in ‘motherese’ can be effective techniques for men to adopt in order to counteract their naturally-intimidating appearance. However, there are more subtle postural signals and senses that influence a dog’s perception of the different genders.

Undeniably, women, as a whole, score much higher on neurotic traits than men. Across the globe, women tend to be more frequently and more severely affected by anxiety, depression and extreme emotional states [Lynn & Martin, 1997]. The effect of neurosis on dogs is a complex area, but if a dog-owner scores highly on neurotic traits, their dog will often display a closer bond with and spend more time in close proximity to their owner [Wedl et al., 2010]. Female dog-owners tend to outscore men on all components used to measure dog-human companionship experience, although there may be bias derived from reluctance in some men to discuss the more emotional aspects of dog ownership [Dotson, 2008]. Interestingly, although the higher level of neuroticism usually displayed by women may make them more emotional, some studies have shown that it is men (who) are more prone to act impulsively upon their emotions. When faced with behavioural problems in dogs, women are more likely to view the dog as blame-free, act encouragingly and are less likely to become irritated, angry or resort to power-assertion behaviour as an attempt to control the problem [Ben-Michael, 2005]. Perhaps the combination of innate gender traits, soothing behaviours, emotional lucidity and lower impulsivity contribute to the quicker onset of trust for women that can occur in fearful dogs. Although often seen as a man’s companion, some strands of domestic dogs’ ancestors may have spent more time with women in primitive societies. There is evidence to suggest that, in ancient hunter-gatherer communities, the women used wolves or feral dogs to assist and protect them while hunting and scavenging for food, whilst the men hunted alone [Taylor et al., 2000]. Therefore, these dogs may have been nurtured similarly to children by the women in these historic groups and, consequently, the ability for dogs to form close bonds with and easily interpret the behaviour of women would have been crucial for survival. If this social structure was common amongst ancestral dogs, the dog-woman bond would have been under greater selective pressure and, thus, shaped and accentuated over thousands of evolutionary years.

One particular hormone, oxytocin, may have a particularly strong role in the gender-bias seen in anxious dogs. Oxytocin is involved in the bonding process between dog and owner and may in part explain why dogs are often quicker to bond with and trust unfamiliar women than men. Oxytocin is known as the bonding hormone because it solidifies and maintains deep, unconditional bonds, most strongly between mother and child but also sexual partners. It works by producing a calm, relaxed and happy emotional state in both individuals involved in the bond [Mitsui et al., 2011]. Oxytocin boosts individual mood, reinforces relationships and is also very beneficial to long-term health, reducing chronic anxiety and fears, increasing resilience and promoting trust and loyalty [Kirsch et al., 2005]. Oxytocin also enhances sociability by improving an individual’s capability to detect and interpret social cues and body language, identify individuals and participate in bonding behaviours [Olivia et al., 2014]. In many ways, oxytocin is a self-reinforcing hormone. It forms an internal positive feedback loop by making the individual feel good and less stressed, giving it an addictive quality which encourages the individual to continue to seek out and bond with the other individual. This hormone also produces an external positive feedback between the two bonded individuals, as an increase in oxytocin in one will be mimicked autonomously in the other [Nagasawa et al., 2015]. One of the most remarkable components in the domestication of dogs and co-evolution with humans is the development of a consistent and strong cross-species oxytocin feedback loop between dog and human. It is phenomenal, really, that owner-dog interactions are capable of producing the same level of oxytocin that would be induced through mother-child relationships [Nagawasa et al., 2009]. In fact, oxytocin levels rise in dogs and their owners after only a few seconds of interaction, such as stroking or even simply prolonged gazing. Like humans, dogs experience the same boost in mood, optimism, stress-reduction, loyalty and health benefits from oxytocin-reinforced bonding [Kis et al., 2014]. One downside to strong oxytocin bonds however, is the risk of increased separation anxiety and protectiveness in some dogs, especially those with a single owner who possesses neurotic or needy traits [Taylor, 2006].

Oxytocin bonds are certainly influenced by gender effects in humans. Due to the mother-centric origin of oxytocin’s role in bonding, women do seem to naturally benefit from and utilise this hormone more than men and this appears to translate to interactions with dogs, too. In a study investigating male and female humans’ hormonal responses to interaction with a dog, women were found to have significantly increased oxytocin levels after interacting with a dog, whereas the oxytocin levels in men actually decreased during the experiment. Oestrogen stimulates oxytocin production, so the higher levels of oestrogen in women will result in increased oxytocin secretion and the maintenance of prolonged high oxytocin levels [Miller et al., 2009]. Dogs are capable of significant feedback loops with bonded humans [Handlin et al., 2015] and have been shown to display increased bonding behaviour and oxytocin levels in response to the scent of oxytocin [Nagawasa et al., 2015]. Therefore, although oxytocin levels were only measured in humans in Miller’s study, it can be assumed that the dogs interacting with the women also produced higher levels of oxytocin than those interacting with the men. The effect of increased oxytocin production by women could contribute to the faster bonding rate often seen between dogs and new women. Moreover, oxytocin induces changes in the brain that increase social cognition and trust and reduce anxiety responses to threatening faces or environments [Kirsch et al., 2005] and also augments a human or dog’s ability to recognise body language and motion cues [Olivia et al., 2014]. Thus, if a dog has a high level of oxytocin circulating when encountering an unfamiliar place or person, they are less likely to react negatively to, and more likely to correctly interpret cues within, the experience. So if women tend to produce higher oxytocin concentrations when interacting with dogs whilst men show reduced oxytocin, there may be a transferrable effect onto dogs that not only increases trusting tendencies towards women, but also means that the dogs are less likely to experience social anxiety and misunderstand social or behavioural cues when interacting with a woman.

People who have a rescue dog with a phobia of men, particularly if this is biased towards a certain type of man, such as a bearded or hat-wearing, will often assume that the fear is a result of previous negative experiences. Admittedly, when dogs have an unknown history, they are statistically more likely to have had positive experiences with women than with men. Although it would not be remotely fair to tar an entire gender with the same brush, women statistically provide a higher level of care and affection towards domestic animals than men [Maritia et al., 2012]. Additionally, men are much more likely to use harsh physical and emotional punishment techniques when training dogs [Schilder & van der Borg, 2004] and are more prone to exhibit negative attitudes towards animals. Overwhelmingly, men overpopulate women in cases of violence towards and persecution of animals [Herzog, 2007] and street dogs are particularly susceptible to experience bad handling by men, considering 95% of dog-catchers are male [Night Talker, 2017]. These trends are statistically relevant across the globe so, although many men are, of course, nurturing and kind towards animals, it is an unarguable fact that more dogs will have been abused or mistreated by male humans than female. Dogs are certainly capable of distinguishing gender and of developing fear towards one type of person based on past experiences [Doring et al., 2009] and this association can be formed very quickly based on only brief negative or positive interactions. For instance, in one recent study, dogs were shown to be able to classify men and women as selfish or generous and act upon this, after only a few brief experimental repetitions [Carballo et al., 2015]. Interestingly, dogs appear to be more skilled at recognising and associating distinct faces and voices in men as opposed to women, so may be more equipped to form distinct memories too [Yong & Ruffman, 2015]. Furthermore, if a dog has a negative experience in the presence of a male human odour, the interpretation of this scent and similar smells can be altered to the extent that it becomes a trigger for anxiety in future interactions, even without any future threat being present. So, for instance, if a dog has been traumatically seized by a male dog-catcher while roaming the streets, they may be apt to react fearfully towards the smell of any man in the future. It is advantageous to be naturally wary of something that has been detrimental in the past, so any fear association that a dog learns is unfortunately much slower to dissolve than it is to create [de Groot 2015]. Therefore, although there are undoubtedly many more factors that would contribute to a fear of men, the possibility of past experiences playing a role cannot be discounted.

Many other aspects of a dog’s history could cause a predisposition to certain anxieties, including fear of men. Dogs acquired as strays or from shelters are more likely to display any behavioural problem than a dog that originated from a breeder or other non-rescue source [Jagoe, 1994]. This is to be expected, considering most rescue dogs will have experienced mild to severe physical, social, psychological or environmental deprivation and possibly maltreatment too. Moreover, prolonged habituation to a caged environments in particular will cause dogs to be more wary of approaching humans [Wells & Hepper, 2000], probably due to the effects of limited space and inability to escape or move away making dogs more defensive. The more intimidating a human appears, the more likely to elicit a defensive response. Young dogs are especially vulnerable to anxiety as a result of being raised in an enclosed space. One wide-ranging study found that all dogs who endured prolonged periods of being caged or enclosed during their early puppyhood were at high risk of displaying aggression towards people in later life. Due to physical restriction and limited positive social interaction, dogs obtained from pet stores are most likely to develop both owner-directed aggression and specific social fears, usually of men, children or strangers [McMillan et al., 2013]. Additionally, dogs raised in less-than-ideal conditions are prone to illness during development and individuals who contract illnesses during their first 16 weeks of life are substantially more likely to display fearful or aggressive behaviours in later life [Podbersceka & Serpell, 1997]. Perhaps this is due to associated developmental delays, or a need for greater self-defence as a result of the vulnerability that accompanies ill-health. Nutritional deficiencies undoubtedly also have an effect on behaviour and fearfulness, as well as predisposition to illnesses, and the introduction of a higher quality diet can significantly reduce anxious behaviour in shelter dogs [Hennessy et al., 2002]. Kennels are highly stressful environments for even the most robust of dogs and social isolation can cause rapid deterioration in a dog’s behaviour and coping strategies. However, many studies have found that short sessions of human interaction can greatly reduce the chronic stress load of dogs in shelters, particularly if these sessions are initiated very soon after the dog’s arrival. Any positive interaction seems to benefit dogs, including feeding, petting and play. Therefore, careful and frequent positive exposure to a wide variety of visiting humans, good nutrition and some freedom of movement could significantly reduce trauma and anxiety for shelter dogs [Coppola et al., 2006]. For many shelters, of course, resources and time are too limited to implement these changes. Even when rescue organisations are able to employ socialisation programmes, the majority of animal volunteers are female so the dogs may exclusively habituate to women. Fortunately, the readiness of many shelter dogs to form new human attachments, combined with adopter’s general greater tolerance for behavioural problems, secures success for many adopted dogs presenting with anxieties [Gacsi et al., 2001].

Dogs that are under an unusual amount of stress, such as after moving to a new home or being introduced to a new family member, are much more likely be proactively defensive and high levels of stress can manifest as bites from dogs who would otherwise be placid [Reisner et al., 2011]. Most officially-reported dog bites are inflicted upon children, presumably because children tend to be less skilled at interpreting canine body language and more likely to crowd or rush at a dog, often presenting towards the dog with close facial proximity. This proximity also tends to result in more serious bites as opposed to adults, who would be more often to reach out with limbs rather than their faces [Reisner et al., 2011]. However, it is important to note when addressing bite statistics that there may be significant bias towards formally reporting a bite when the individual is a minor as opposed to an adult. Unreported bites are more likely to involve adults and to occur within a private residence. For instance, in a postal survey of springer spaniels, nearly half of the dogs surveyed had shown aggressive behaviour towards family members and twice as many of the reported aggressive behaviours were directed towards adults than children [Reisner et al., 2005]. Some breeds, including springer spaniels, are known to be more likely to direct aggression towards their owners, whereas other breeds, often the shepherd and guarding types, show much greater aggressive tendencies towards strangers or intruders [Vas et al., 2007]. Genetics undoubtedly play a role in both fear and aggression. As property-guarding and livestock-guarding breeds have been genetically wired to be more alert, territorial and sensitive to different types of approach, it is not surprising that they are predisposed to react defensively or aggressively towards unfamiliar people. Guarding breeds are also much more likely to pick up on cues from a stranger that suggest they may be a threat, such as tense body language, direct approach and pointed gazing [Vas et al., 2005]. As aforementioned, this is particularly the case with strangers due to lack of familiarity. In simulations, dogs usually react with aggression or avoidance towards a purposely threatening advance from a stranger, yet respond playfully if the same scenario is performed by their owners [Gyori et al., 2010]. Breed or type cannot be used to reliably predict aggressive predisposition, however, and no dog is ‘bombproof’. Labrador retrievers contribute to a significant proportion of bite cases in many western countries, most likely due to their popularity rather than genetics. General public perception of the breed as being of fine temperament may also lead to individual labradors being placed in more stressful situations with less caution than some other breeds [Guy et al., 2001]. When considering reported bite incidents as a whole, male humans are significantly more likely to be bitten by a dog than females across almost all age groups, including children. Men also make up the majority of dog bite fatalities, possibly due to potential for testosterone to increase the severity of aggressive reactions. This gender trend has been found in studies across the globe [Overall & Love, 2001] and applies both to strangers and to members of the household. Greater numbers of people living within the home correlates positively with increased aggression in dogs, but owner-directed aggression is nevertheless far more likely to occur towards male owners [Pirrone et al., 2015].

Anonymous surveys of dog-owners can be reliable and convenient ways of collecting data on dog behaviour. People are more likely to be honest about any problems they are experiencing, particularly when their dogs have aggressive tendencies, if their identity is not known [Hsu & Sun, 2010]. Nonspecific surveys also reduce selection bias that would occur if using dog bite statistics or owner-relinquishment surveys as sources of data. In an anonymous author-conducted survey involving a variety of dog-owners and their dogs, 40% of dogs were reported to have displayed fear or aggression towards people. Of these dogs, 67% were from a rescue origin, split equally between rescues from national centres and imports from abroad. Around half of the rescue dogs included in this survey displayed fear or aggression towards people, as opposed to only 24% of dogs obtained from a breeder. This is in line with the general findings that rescue dogs are more at risk of suffering with anxiety around people [Wells & Hepper, 2000]. Male adults were the most likely to be triggers of fear or aggression in any context, with 55% of the problem behaviours being directed towards men. Interestingly, children were reported as triggers of fear or aggression in only 8% of cases, most of which involved children visiting the home, rather than members of the family or children met outside. Amongst the dogs who showed problematic behaviours, by far the most common trigger was adult males visiting the house, with over half of the dogs reported as having reacted negatively towards men visiting their home. However, the majority (60%) of the 244 dogs involved in this survey had not displayed problematic behaviour towards people, which is a promising statistic. Out of the responses in which problems did occur, slightly over half expressed the wish for more help with their dog’s fear or aggression. This highlights the fact that more needs to be done to increase awareness of the reasons behind people-directed hostility in dogs and the ways in which owners can safely help their dogs combat their reservations.

Out of all the perceived behavioural problems a dog can display, aversion towards humans is the one that tends to evoke the most distress or worry for owners and handlers. It is important, however, that the root of the behaviour is addressed sensitively and carefully. When people resort to harsh physical punishment, they are at risk of greatly increasing the dog’s fear and reactivity. Both verbal and physical punishment have the potential to increase stress levels in dogs [Horvath et al., 2008]. In Reisner’s study of springer spaniels, around a third of the reported owner-directed aggression had occurred as a response to their use of physical punishment. Considering men are statistically more likely to use assertive and physical methods to tackle their dog’s behaviour and dogs often react with greater intensity towards men, the danger of these techniques must be considered [Ben-Michael, 2005]. Fear is the most common antecedent to aggression, especially when the dog’s ability to flee is restricted, as in a home or kennel environment and when tethered by a lead. Almost all fearful dogs have the capacity to improve, and some do so significantly, but an improved dog is never ‘cured’ and care must always be taken to avoid unnecessary stress [London, 2011]. Fear of people is usually one of the most resolute anxieties amongst dogs and tends to be longer-lasting than object- or environment-specific fears [Dykman et al., 1979]. Therefore, it is vital that owners and handlers are prepared to commit time and patience.

A long-term study conducted on failed working dogs that displayed people-directed fear (either men, strangers or children) found counter-conditioning to be the most effective technique, followed by systematic desensitisation[Gunrow, 1995]. Counter-conditioning entails changing the meaning of a particular stimulus, in this case the feared type of person, so that a dog’s default response to this stimulus changes. This is best used in combination with desensitisation, which involves initially exposing the dog to the stimulus at such a low intensity that it does not elicit a negative reaction, then gradually increasing the intensity of the stimulus in a pace that never pushes the dog over the threshold into a fear response. If these two techniques are to function successfully, the human needs to ensure the dog remains calm enough around a stimulus to choose a new taught behaviour, in place of a fearful or aggressive response. Counter-conditioning and desensitisation work best at tackling fear-based behaviours because they work to not only reduce the levels of fear a dog experiences in response to triggers, but also change the way the dog deals with this fear. Other techniques, such as punishment, flooding or total avoidance, are not very effective because they do not work to reduce a dog’s anxiety levels and may even increase both acute and chronic stress [Schilder & van der Borg, 2004]. Not only do fear and stress pose risks to dogs’ wellbeing, they also severely impact a dog’s cognitive ability, to the point that a severely stressed dog is often unable to learn new behaviours or associations. When working with a people phobic-dog, the dog should be habituated to the least-feared type of person first, such as a small, dog-experienced man on neutral territory, ensuring only positive experiences around this low-intensity trigger. Once the dog is calm and comfortable around this lower-intensity trigger, the handler can gradually increase the intensity of the trigger, eventually working with a highly feared person, such as a large, bearded man for instance [Landsberg et al., 2012]. Interestingly, once a dog is experiencing significantly increased cortisol levels, soothing touch from a familiar human will be ineffective at reducing the stress the dog is experiencing, unless the fear itself can be reduced. One study found that, although hormones such as dopamine, oxytocin and endorphins increased in both humans and dogs during positive interactions, cortisol only decreased in the humans [Odendaal, 2000]. Thus, if a dog becomes highly stressed, it is important to decrease the intensity of a stress trigger, for instance by creating further distance between the dog and a feared human, in combination with tactile reassurance.

Seeking help from a trainer or behaviourist is an important first step for owners who are struggling with a people-phobic dog and this can provide the owners with reassurance and tools with which to continue assisting the dog in daily life [Kubinyi et al., 2009]. Alongside training techniques, pheromones can reduce stress in dogs and, although these techniques are hit-and-miss, appeasing pheromone collars in particular have been proven to reduce anxiety in some dogs [Thompson, 2016]. Neutering or spaying a dog can help in some individuals, but must be timed correctly to avoid exacerbating nervousness. In severe cases of anxiety, medication such as chlorpromazine can be of great help to dogs, but any medication must be combined with behavioural modification to have a long-term positive effect and should be a last resort [Blacksaw, 1991]. High quality nutrition is also important for anxious dogs, as well as regular feeding times to ensure the dog does not go hungry for prolonged periods, as this can contribute to impulsivity and stress [Hennessy et al., 2002].

In terms of hormonal and physical differences between the genders, there is little that can be done to change the way a nervous dog perceives a man. However, there are many ways in which a man, or any feared person, can change their body language to appear less threatening to dogs. During greetings, the act of crouching down low to the ground, so as not to loom over the dog, usually helps a person seem less tense and intimidating. Peaceful intent can be further suggested to dogs by adopting a loose, open-armed posture, preferably with the body either leaning away from, or facing at a different angle to, the dog. When a dog is being habituated to a new person, the dog should not be approached directly and needs to be given space to retreat if desired. If there is a risk of biting, a barrier such as a baby gate could be used so that the dog can observe the feared person from a distance without physical contact. This may be necessary during times of high stress, such as when a dog first moves into a home or is being introduced to a new person. The new person should avoid eye contact at first. Although mutual gazing can be a very effective bonding activity between dog and owner and is not always viewed by dogs to predict danger, eye-contact can be interpreted as a threat if combined with a sense of ambiguity or other fear triggers [Vas et al., 2005]. As dogs are prone to greater vigilance around men, subtle tension in a man’s body is more likely to be noticed [Lore & Eisenberg, 1986] and the effect of testosterone and other hormones will contribute to increased reactivity to these cues. Thus, men, on average, may unfortunately have to work harder than women to gain an anxious dog’s trust.

As much as it is vital for a dog to remain below threshold when encountering feared people, it is also very important that the people remain as calm and relaxed as possible. Relaxed body language will help, but if the person becomes apprehensive about a dog’s reaction, the dog is likely to be aware of this and, at that point, body language cues are likely to be overridden in the dog’s perception, with olfactory signals of fear taking priority [Mutic et al., 2016]. The greater potency of sweat and higher concentration of testosterone, androsterone and fear or aggression chemosignals emanating from men will, again, exacerbate this effect, making a stressed man innately more conspicuous to dogs than a woman in the same state [de Groot et al., 2012]. Dogs are very sensitive to human emotion and are more likely to perform bonding behaviour with a human if they are in a happy mood [Morisaki, 2009]. Due to oxytocin benefits and social security, the act of bonding with a human can be incredibly effective at reducing chronic stress in dogs. The modern canine species has evolved over thousands of years to be highly dependent on their human guardians, almost to the same extent at which children require parental care to thrive. Thus, solid human companionship is vital for the psychological and physical health of canines. New rescue dogs are often most fearful and reactive before they have formed attachment bonds with their new family. Therefore, if a dog is initially very anxious around the adult male in a new home, the simple act of bonding with other members of the family may in turn encourage the dog to be more willing to interact with the feared individual, eventually leading to trust and attachment [Payne et al., 2015]. Once the dog is ready to interact with the feared person or people, there are many bonding activities that would be most effective at gaining trust. As much as possible, the person should attempt to be the source of all positive aspects of a dog’s daily life. Most dogs value food very highly, so if the feared human can be the source of the majority of the dog’s daily nutritional intake, this can be incredibly beneficial to the relationship. As new dogs are most likely to fear the man of their human family, it is often recommended by rescue groups that all meals should come from the man. Food rewards, stuffed kongs and periodic food offerings, for instance throwing treats casually across the room towards the dog, are also very helpful for gaining trust. Provided the dog enjoys going outside, the man should participate in as many walks as possible, preferably engaging the dog in play, praise and training at the same time. This not only increases positive experience and interaction with the feared individual, it also allows the dog to interact with the person outside of the home environment. Dogs are often less guarded when on neutral territory [Landsberg et al., 2012]. In a similar manner as with human children, loose and unstructured play activities can be incredibly therapeutic and effective towards reducing anxiety in dogs. Some play techniques that lead to high levels of arousal, such as tug and rough-and-tumble, would not be appropriate in these cases due to the high impulsivity and tactile nature of the play. However, low-contact activities such as fetch and gentle object-based play could be effective at increasing the dog’s affection for the person involved [Horvath et al., 2008].

Above all, the most important factor in reducing a dog’s anxiety of people is time and patience. This is particularly the case with fear of men, due to all of the gender-specific factors that can combine to trigger anxiety in dogs. The amount of time a dog and human spend together directly augments the bond they experience [Payne et al., 2015]. Even though trust may be less readily offered to men by some dogs, attachments and relationships formed between men and their dogs are just as intimate, valuable and rewarding as with women. Dogs do not, by and large, fear or dislike men, but many of the factors discussed in this investigation will make a fear of men more likely. Phobias in dogs are often generalised to cues that humans would otherwise hardly even notice and certainly, there are cases in which dogs are more receptive towards and trusting of men and fearful of women. Thus, dogs do not show a general gender bias, but are strongly influenced by innate gender characteristics and also past experience. Needless to say, men benefit immensely from their canine companions and some associated health benefits of dog-ownership can in fact be more pronounced in male humans. For instance, dog-ownership lowers the blood pressure and cholesterol levels in male owner but not females [Robinson, 1995]. Likewise, men, with their greater physical strength and lower tendencies for neuroticism, often provide man’s best friend with a greater sense of protection, more physical engagement in play and a unique bonding style. Securing a bond with a highly timid or reactive dog can be a long process, especially when the human half of the bond is a trigger for the anxiety. Fear and aggression are both crucial for survival and therefore the associated behaviours are never really irrational, even if not in occurrence with actual threat. Thus, learnt responses can take a long time to dissolve. It is testament to the special bonding abilities between humans and dogs that, even when dogs show initial wariness and fear towards a person, this can usually be overcome and eventually replaced with loyalty and trust or the previously-feared individual.

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