Dog behavior
Dog behavior is the internally coordinated responses of individuals or groups of domestic dogs to internal and external stimuli. It has been shaped by millennia of contact with humans and their lifestyles. As a result of this physical and social evolution, dogs have acquired the ability to understand and communicate with humans. Behavioral scientists have uncovered a wide range of social-cognitive abilities in domestic dogs. Dog behavior is influenced from a combination of many physiological factors, environmental conditions or issues, and human interaction; all of which play a part in the development of a dog's behavior and welfare.
Co-evolution with humans
The origin of the domestic dog is not clear. Whole-genome sequencing indicates that the dog, the gray wolf and the extinct Taymyr wolf diverged around the same time 27,000–40,000 years ago. How dogs became domesticated is not clear, however the two main hypotheses are self-domestication or human domestication. There exists evidence of human-canine behavioral coevolution.Intelligence
Dog intelligence is the ability of the dog to perceive information and retain it as knowledge in order to solve problems. Dogs have been shown to learn by inference. A study with Rico showed that he knew the labels of over 200 different items. He inferred the names of novel items by exclusion learning and correctly retrieved those novel items immediately. He also retained this ability four weeks after the initial exposure. Dogs have advanced memory skills. A study documented the learning and memory capabilities of a border collie, "Chaser", who had learned the names and could associate by verbal command over 1,000 words. Dogs are able to read and react appropriately to human body language such as gesturing and pointing, and to understand human voice commands. After undergoing training to solve a simple manipulation task, dogs that are faced with an insolvable version of the same problem look at the human, while socialized wolves do not. Dogs demonstrate a theory of mind by engaging in deception.Senses
The dog's senses include vision, hearing, sense of smell, taste, touch, proprioception, and sensitivity to the Earth's magnetic field.Communication behavior
Dog communication is about how dogs "speak" to each other, how they understand messages that humans send to them, and how humans can translate the ideas that dogs are trying to transmit. These communication behaviors include eye gaze, facial expression, vocalization, body posture and gustatory communication. Humans communicate with dogs by using vocalization, hand signals, and body posture. Dogs can also learn to understand the communication of emotions with humans by reading human facial expressions.Social behavior
Two studies have indicated that dog behavior vary based on their size, body weight, and skull size.Play
Dog and dog
Play between dogs usually involves several behaviors often seen in aggressive encounters, such as nipping, biting and growling. It is therefore important for the dogs to place these behaviors in the context of the play, rather than aggression. Dogs signal their intent to play with a range of behaviors including a "play-bow", "face-paw", "open-mouthed play face" and postures inviting the other dog to chase the initiator. Similar signals are given throughout the play to maintain the context of the potentially aggressive activities.From a young age, dogs engage in play with one another. Dog play is made up primarily of mock fights. It is believed that this behavior, which is most common in puppies, is training for important behaviors later in life. Some early socialization methods, such as puppy classes or "puppy parties" have been shown to positively influence adult dog behavior. Play between puppies is not necessarily a 50:50 symmetry of dominant and submissive roles between the individuals; dogs who engage in greater rates of dominant behaviors at later ages also initiate play at higher rates. This could imply that winning during play becomes more important as puppies mature.
Emotional contagion is linked to facial mimicry in humans and primates. Facial mimicry is an automatic response that occurs in less than 1 second in which one person involuntarily mimics another person's facial expressions, forming empathy. It has also been found in dogs at play, and play sessions lasted longer when there were facial mimicry signals from one dog to another.
Dog and human
The motivation for a dog to play with another dog is different from that of a dog playing with a human. Dogs walked together with opportunities to play with one another and play with their owners, choose to play with their owners at the same frequency as dogs being walked alone. Dogs in households with two or more dogs only play slightly more often with their owners than dogs in households with a single dog, indicating the motivation to play with other dogs does not substitute for the motivation to play with humans.It is a common misconception that winning and losing games such as "tug-of-war" and "rough-and-tumble" can influence a dog's dominant relationship with humans. Rather, how dogs play indicates their temperament and relationship with their owner. Dogs that play rough-and-tumble are more amenable and show lower separation anxiety than dogs which play other types of games, and dogs playing tug-of-war and "fetch" are more confident. Dogs that start most games are less amenable and more likely to be aggressive.
Scientific studies highlight the unique bonds between humans and dogs, showing how friendship and communication has evolved through domestication. Playing with humans can affect the cortisol levels of dogs. In one study, the cortisol responses of police dogs and border guard dogs were assessed after playing with their handlers. The cortisol concentrations of the police dogs increased, whereas the border guard dogs' hormone levels decreased. The researchers noted that during the play sessions, police officers were disciplining their dogs, whereas the border guards were truly playing with them, i.e. this included bonding and affectionate behaviors. They commented that several studies have shown that behaviors associated with control, authority or aggression increase cortisol, whereas play and affiliation behavior decrease cortisol levels.
Empathy
In 2012, a study found that dogs oriented toward their owner or a stranger more often when the person was pretending to cry than when they were talking or humming. When the stranger pretended to cry, rather than approaching their usual source of comfort, their owner, dogs sniffed, nuzzled and licked the stranger instead. The dogs' pattern of response was behaviorally consistent with an expression of empathic concern.A study found a third of dogs suffered from anxiety when separated from others.
Personalities
The term personality has been applied to human research, whereas the term temperament has been mostly used for animal research. However, both terms have been used interchangeably in the literature, or purely to distinguish humans from animals and avoid anthropomorphism.Personality can be defined as "a set of behaviors that are consistent over context and time". Studies of dogs' personalities have tried to identify the presence of broad personality traits that are stable and consistent over time.
There are different approaches to assess dog personality:
Several potential personality traits have been identified in dogs, for instance "Playfulness", "Curiosity/Fearlessness, "Chase-proneness", "Sociability and Aggressiveness" and "Shyness–Boldness". A meta-analysis of 51 published peer-reviewed articles identified seven dimensions of canine personality:
- Reactivity
- Fearfulness
- Activity
- Sociability
- Responsiveness to training
- Submissiveness
- Aggression
The effects of age and sex have not been clearly determined. The personality models can be used for a range of tasks, including guide and working dog selection, finding appropriate families to re-home shelter dogs, or selecting breeding stock.
Leadership, dominance and social groups
Dominance is a descriptive term for the relationship between pairs of individuals. Among ethologists, dominance has been defined as "an attribute of the pattern of repeated, antagonistic interactions between two individuals, characterized by a consistent outcome in favor of the same dyad member and a default yielding response of its opponent rather than escalation. The status of the consistent winner is dominant and that of the loser subordinate." Another definition is that a dominant animal has "priority of access to resources". Dominance is a relative attribute, not absolute; there is no reason to assume that a high-ranking individual in one group would also become high ranking if moved to another. Nor is there any good evidence that "dominance" is a lifelong character trait. Competitive behavior characterized by confident and submissive patterns exchanged.One test to ascertain in which group the dominant dog was used the following criteria: When a stranger comes to the house, which dog starts to bark first or if they start to bark together, which dog barks more or longer? Which dog licks more often the other dog's mouth? If the dogs get food at the same time and at the same spot, which dog starts to eat first or eats the other dog's food? If the dogs start to fight, which dog usually wins?
Domestic dogs appear to pay little attention to relative size, despite the large weight differences between the largest and smallest individuals; for example, size was not a predictor of the outcome of encounters between dogs meeting while being exercised by their owners nor was size correlated with neutered male dogs. Therefore, many dogs do not appear to pay much attention to the actual fighting ability of their opponent, presumably allowing differences in motivation and perceived motivation to play a much greater role.
Two dogs that are contesting possession of a highly valued resource for the first time, if one is in a state of emotional arousal, in pain; if reactivity is influenced by recent endocrine changes, or motivational states such as hunger, then the outcome of the interaction may be different than if none of these factors were present. Equally, the threshold at which aggression is shown may be influenced by a range of medical factors, or, in some cases, precipitated entirely by pathological disorders. Hence, the contextual and physiological factors present when two dogs first encounter each other may profoundly influence the long-term nature of the relationship between those dogs. The complexity of the factors involved in this type of learning means that dogs may develop different "expectations" about the likely response of another individual for each resource in a range of different situations. Puppies learn early not to challenge an older dog and this respect stays with them into adulthood. When adult animals meet for the first time, they have no expectations of the behavior of the other: they will both, therefore, be initially anxious and vigilant in this encounter, until they start to be able to predict the responses of the other individual. The outcome of these early adult–adult interactions will be influenced by the specific factors present at the time of the initial encounters. As well as contextual and physiological factors, the experiences of each member of the dyad of other dogs will also influence their behavior.