Interspecies friendship

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Two goats and a cat sitting in the shade Best Friends (2772098889).jpg
Two goats and a cat sitting in the shade

An interspecies friendship is a nonsexual bond that is formed between animals of different species. [1] Numerous cases of interspecies friendships among wild and domesticated animals have been reported and documented with photography and video. [1] Domestication of animals has led to interspecies friendships between species that would never naturally exist together. In many cases of interspecies friendship, the species are not normally seen together, and sometimes, one is of a species that ordinarily preys on the other in nature. [2]

Contents

The concept of interspecies friendship is similar to that of mutualism in that two individuals from different species exist in a relationship where each organism benefits from the activity of the other. Reasons for the formation of interspecies friendships include domestication, interspecies communication, mutually beneficial exchanges, desire for social bonding, protection, or is often unknown. [2] [3] [4]

Friendships between humans and other animals

Dogs

The relationship between a human and a household dog (Canis lupus familiaris) is quite common and said to be similar to the relationship seen between a parent and child. [5] Many people agree that there is an emotional bond between themselves and their dog. [6] An important indicator of the bond between a dog and its caregiver can be seen through separation and reunion incidences. The behaviour of the dog including approach latency and the frequency of initiating physical contact varies according to how familiar the dog is with the person. [7] This can be viewed as a snapshot of their relationship. [6] Behaviours such as tail wagging, lip licking, body shaking and vocalization also indicate this. [6]

The relationship between humans and dogs is so impactful that therapy dogs are a common practice. From hospitals to schools, dogs help comfort humans. [8]

Cats

A human petting a cat Amor a los animales.jpg
A human petting a cat

Friendships between household cats (Felis catus) and humans are also very common. The relationship between cats and humans dates back over 10,000 years. Cats even had great influence in ancient Egypt. [9] Today, cats live in many countries and are the most popular choice of pet. [10] [11] Cat owners often consider their cat as an integrated part of their family and indicate that they are easy to care for and engage in social behaviours such as allowing humans to hold, pet and play with them. [10] [11] Mutual affection and bonding is displayed between cats and their owners, indicating a sense of friendship. [11]

Horses

A human touching a horse's muzzle Lipica-2902867.jpg
A human touching a horse's muzzle

Friendships between humans and domesticated horses (E. ferus) are often observed and occur when the horse is willing to allow the person into its flight distance and personal space through friendly interactions such as grooming, scratching and rubbing. [12] Horses are social animals and once a person is accepted into their personal space, they become a part of their social system. [12] A domesticated horse will work hard for praise from its human partner and can be easily trained to respond to human commands. [12] Many people report strong feelings of friendship with their horse and believe that their horse considers them to be its friend, protector, and caretaker. [13]

Non-domesticated animals

Interspecies friendships have been displayed between humans and non-domesticated animals. Some examples include:

Friendships between non-human animals

A cat and dog bonding Interspecies Friendship.jpg
A cat and dog bonding

Dogs and cats

Dogs (Canis lupus familaris) and cats (Felis catus) that coexist in close quarters are two unrelated species that often display companionship towards each other. [1] [17] Many coexisting dogs and cats exhibit friendly relationships involving behaviours such as playing and sleeping together, grooming each other and understanding differences in body language and communication. [17] Dogs and cats often engage in mutual nose sniffing which is a form of greeting displayed in cats that is not normally observed in dogs. Dogs may acquire this behaviour from the understanding of cat communication signals. [17]

Other examples

A Tufted gray langur (Semnopithecus priam) stroking a Grizzled giant squirrel (Ratufa macroura) caringly at Yala National Park, Sri Lanka Interspecies Bonding.jpg
A Tufted gray langur (Semnopithecus priam) stroking a Grizzled giant squirrel (Ratufa macroura) caringly at Yala National Park, Sri Lanka

There are many documented instances of unusual interspecies friendships. Some examples include:

Why interspecies friendships form

Domestication

Domestication is defined as a multi-generational relationship in which one group of organisms assumes a significant degree of influence over the reproduction and care of another group to secure a more predictable supply of resources from that second group.

In the previous 11,000 years, humans have brought a wide range of species into domestication to use as livestock, working animals, household pets, and companions. [27] The influence of human behaviour on domesticated animals has led to many species having learned to co-exist - sometimes leading to the formation of an interspecies friendship. For example, interspecies friendships are often observed in humans with their domesticated pets and in pets that live in the same household such as cats and dogs. [1] [17]

Interspecies communication

Interspecies communication can form the basis of an interspecies friendship because it facilitates mutualism and bonds between animals. [28] Species can communicate to each other both verbally and non-verbally as seen in human-dog communication. [3] The communication exhibited between dogs and humans allow friendships to form which is often displayed through social bonding activities such as play. [3] Interspecific communication is an effective way of forming mutuality and interspecies friendships in the wild which often involves different species warning each other about potential danger approaching. [29] Species of monkeys have been observed to communicate with each other through their alarm calls leading to mutuality between the counterparts. [30] In particular, West African Diana monkeys and Campbell's monkeys seem to understand and react to the alarm calls of the other species and form associations with each other through mutual protection. [30]

Mutualism

Mutualism can contribute to the formation of interspecies friendships because it involves a pair of organisms experiencing mutually beneficial exchanges with each other which may lead to a long-lasting bond. The mutualistic relationship observed between coyotes and badgers after hunting ground squirrels together is an example of mutualism developing into an unlikely interspecies friendship. [2] Interspecies friendships often form between humans and domesticated animals through mutualism in which the human gains something beneficial from their pet and the pet gains something beneficial from the human. [31] This is often observed in human-canine friendships in which dogs benefit by being cared for and offered love and companionship from humans while humans benefit by receiving companionship, loyalty and love from their dogs. [32] Mutualistic relationships can be observed even in the smallest of critters like ants and aphids. Ants deter predators from aphids and aphids produce honeydew for the ants to drink. [33]

Protection

Protective behaviour exhibited from one species onto another can lead to an interspecies friendship as it allows the formation of a bond to occur between species. [34] This is often observed in interspecies adoptions in which a member of one species "adopts" a member of another that is orphaned or hurt. [34] For example, an infant marmoset was adopted by capuchin monkeys and the marmoset became socially included and protected in their group. [34] Other examples include a ram protecting a blind cow and a steer protecting a blind mule. [4] [21] In each circumstance, interspecies friendships are formed after the protectors assumed protective roles.

Social bonding

Many species seek out social bonding with other species which often involves play behaviours. [3] Play can act as a form of communication between companions in which the participants mutually understand that the interaction is playful and pleasurable. [3] Play is specifically fundamental to interactions between humans and their non-human companions such as play exhibited in human-canine bonding. [3] Human-canine play requires that both the human and dog communicate to understand the situation and goal of the game through their actions. Social bonding is observed in many interspecies interactions such as those between humans and their household pets, humans and primates, and many other animals in the wild. [2] [14] [15] [20] Since social bonding involves communication and interactions between different species, it can lead to the development of interspecies friendships.

Trait selection and convergent evolution

Animals often portray many similar characteristics displayed by humans. There exists the belief that while both humans and animals evolve simultaneously, domesticated animals have benefited the most from human-animal relationships because they have increased in population to a far greater extent than would've occurred naturally. This is believed to be because of their selected "human-like" characteristics. [35] The selection of behavioural skills provides a typical environment for convergent evolution.

Canis lupus familiaris

A reunion between a dog and a human Licking dog.jpg
A reunion between a dog and a human

There is a wide range of shared general and specific social skills between humans and dogs including functional and behavioural traits. Sociality, the ability to perform synchronized behaviour and complex constructive skills have each been previously displayed in both dogs and humans. For example, qualities of sociality include lifelong attachment, reduced intra-group aggression, enhanced cooperation. Whereas, synchronized behaviours include imitation, hypnosis and dance and complex constructive skills include mimesis and language. [36] Dogs display specific social skills during interaction with humans for their benefit. Advancement in attachment skills for the dogs enables them further benefit from humans by gaining valuable information, protection and help. [37]

Animals that have evolved social skills gained close integration with humans and their community resulting in more successful species. Human-dog relationships are the most common interspecies friendships, resulting in dogs becoming one of the most successful mammalian species to exist. [36]

See also

Related Research Articles

<span class="mw-page-title-main">Pet</span> Animal kept for companionship rather than utility

A pet, or companion animal, is an animal kept primarily for a person's company or entertainment rather than as a working animal, livestock, or a laboratory animal. Popular pets are often considered to have attractive/cute appearances, intelligence, and relatable personalities, but some pets may be taken in on an altruistic basis and accepted by the owner regardless of these characteristics.

Animal communication is the transfer of information from one or a group of animals to one or more other animals that affects the current or future behavior of the receivers. Information may be sent intentionally, as in a courtship display, or unintentionally, as in the transfer of scent from the predator to prey with kairomones. Information may be transferred to an "audience" of several receivers. Animal communication is a rapidly growing area of study in disciplines including animal behavior, sociology, neurology, and animal cognition. Many aspects of animal behavior, such as symbolic name use, emotional expression, learning, and sexual behavior, are being understood in new ways.

Zoomusicology is the study of the musical aspects of sound and communication as produced and perceived by animals. It is a field of musicology and zoology, and is a type of zoosemiotics. Zoomusicology as a field dates to François-Bernard Mâche's 1983 book Music, Myth, and Nature, or the Dolphins of Arion, and has been developed more recently by scholars such as Dario Martinelli, David Rothenberg, Hollis Taylor, David Teie, and Emily Doolittle.

<span class="mw-page-title-main">Bark (sound)</span> Sound mainly produced by dogs

A bark is a sound most often produced by dogs. Other animals that make this noise include, but are not limited to, wolves, coyotes, foxes, seals, frogs, and barking owls. "Bark" is also a verb that describes the sound of many canids.

<span class="mw-page-title-main">Domestication of vertebrates</span>

The domestication of vertebrates is the mutual relationship between vertebrate animals including birds and mammals, and the humans who have influence on their care and reproduction.

<span class="mw-page-title-main">Human–animal communication</span> Verbal and non-verbal interspecies communication

Human–animal communication is the communication observed between humans and other animals, ranging from non-verbal cues and vocalizations to the use of language.

<span class="mw-page-title-main">Anthrozoology</span> Subset of ethnobiology

Anthrozoology, also known as human–animal studies (HAS), is the subset of ethnobiology that deals with interactions between humans and other animals. It is an interdisciplinary field that overlaps with other disciplines including anthropology, ethnology, medicine, psychology, social work, veterinary medicine, and zoology. A major focus of anthrozoologic research is the quantifying of the positive effects of human–animal relationships on either party and the study of their interactions. It includes scholars from fields such as anthropology, sociology, biology, history and philosophy.

Human bonding is the process of development of a close interpersonal relationship between two or more people. It most commonly takes place between family members or friends, but can also develop among groups, such as sporting teams and whenever people spend time together. Bonding is a mutual, interactive process, and is different from simple liking. It is the process of nurturing social connection.

<span class="mw-page-title-main">Dog</span> Domesticated species of canid

The dog is a domesticated descendant of the wolf. Also called the domestic dog, it was selectively bred from an extinct population of wolves during the Late Pleistocene by hunter-gatherers. The dog was the first species to be domesticated by humans, over 14,000 years ago and before the development of agriculture. Experts estimate that due to their long association with humans, dogs have gained the ability to thrive on a starch-rich diet that would be inadequate for other canids.

<span class="mw-page-title-main">Emotion in animals</span> Research into similarities between non-human and human emotions

Emotion is defined as any mental experience with high intensity and high hedonic content. The existence and nature of emotions in non-human animals are believed to be correlated with those of humans and to have evolved from the same mechanisms. Charles Darwin was one of the first scientists to write about the subject, and his observational approach has since developed into a more robust, hypothesis-driven, scientific approach. Cognitive bias tests and learned helplessness models have shown feelings of optimism and pessimism in a wide range of species, including rats, dogs, cats, rhesus macaques, sheep, chicks, starlings, pigs, and honeybees. Jaak Panksepp played a large role in the study of animal emotion, basing his research on the neurological aspect. Mentioning seven core emotional feelings reflected through a variety of neuro-dynamic limbic emotional action systems, including seeking, fear, rage, lust, care, panic and play. Through brain stimulation and pharmacological challenges, such emotional responses can be effectively monitored.

Growling is a low, guttural vocalization produced by animals as an aggressive warning but can also be found in other contexts such as playful behaviors or mating. Different animals will use growling in specific contexts as a form of communication. In humans, low or dull rumbling noises may also be emitted when they are discontent with something or they are angry, although this human sound is often termed "groaning" & "grunting".

<span class="mw-page-title-main">Dog behavior</span> Internally coordinated responses of dogs to internal and external stimuli

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.

Socialization of animals is the process of training animals so that they can be kept in close relationship to humans.

<span class="mw-page-title-main">Free-ranging dog</span> Dog not confined to a yard or house

A free-ranging dog is a dog that is not confined to a yard or house. Free-ranging dogs include street dogs, village dogs, stray dogs, feral dogs, etc., and may be owned or unowned. The global dog population is estimated to be 900 million, of which around 20% are regarded as owned pets and therefore restrained.

<span class="mw-page-title-main">Human–canine bond</span> Interspecies relationship

The human–canine bond is rooted in the domestication of the dog, which began occurring through their long-term association with hunter-gatherers more than 30,000–40,000 years ago. The earliest known relationship between dogs and humans is attested by the 1914 discovery of the Bonn–Oberkassel dog, who was buried alongside two humans in modern-day Oberkassel, Germany, approximately 15,000 years ago. For centuries, the phrase "man's best friend" has commonly been used to refer to dogs, as they were the first species and the only large carnivore to have been domesticated. This companionship is most evident in Western countries, such as the United States, where 44% of households were found to be keeping at least one dog as a pet.

Cats and dogs have a range of interactions. The natural instincts of each species lead towards antagonistic interactions, though individual animals can have non-aggressive relationships with each other, particularly under conditions where humans have socialized non-aggressive behaviors.

<span class="mw-page-title-main">Non-reproductive sexual behavior in animals</span> Non-reproductive behavior in non-human animals

Animal non-reproductive sexual behavior encompasses sexual activities that non-human animals participate in which do not lead to the reproduction of the species. Although procreation continues to be the primary explanation for sexual behavior in animals, recent observations on animal behavior have given alternative reasons for the engagement in sexual activities by animals. Animals have been observed to engage in sex for social interaction bonding, exchange for significant materials, affection, mentorship pairings, sexual enjoyment, or as demonstration of social rank. Observed non-procreative sexual activities include non-copulatory mounting, oral sex, genital stimulation, anal stimulation, interspecies mating, same-sex sexual interaction, and acts of affection, although it is doubted that they have done this since the beginning of their existence. There have also been observations of sex with cub participants, as well as sex with dead animals.

The term "interspecies family" refers to a group consisting of at least two members of different species who deeply care for each other. Examples include a human and their dog, a couple and their cats, a dog and a cat, or even a mule and a sheep. The emphasis is on love and that the members of the group care for and treat each other like a family. For instance, "interspecies family" may describe a group composed of a dog and a person who refers to their dog as their child, best friend, or other phrase that connotes a stronger bond than just a "pet", a term which implies a sense of property and ownership.

<span class="mw-page-title-main">Calming signals</span> Patterns of behavior in dogs

Calming signals is a term conceived by Norwegian dog trainer and canine ethologist, Turid Rugaas, to describe the patterns of behavior used by dogs interacting with each other in environments that cause heightened stress and when conveying their desires or intentions. The term has been used interchangeably with "appeasement signals." Calming signals, or appeasement signals, are communicative cues used by dogs to de-escalate aggressive encounters or to prevent the development of aggressive encounters completely. Calming signals are performed by one dog and directed towards one or more individual(s), which could be dogs or individuals of other species, such as humans. When calming signals are ignored, a dog may display warning signals of aggression, and this has the potential to escalate to outright conflict between individuals.

<span class="mw-page-title-main">Pet humanization</span> Applying care to pets that approaches human standards

Pet humanization is the practice in pet culture of treating companion animals with a level of care, attention and luxury relatively higher than for the average domesticated animal. This trend involves the owners being at odds with the pet's status as property in wider society and can range from relying on them for emotional support to treating them like human family members.

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