Animal grief

Grief is “a multifaceted response to loss, particularly to the loss of someone or something that has died, to which a bond or affection was formed”. A common emotion amongst humans, grief is also apparent in other animals, known as animal grief. In the late 19th century, research started to show grief in chimpanzees and the connection between animal and human grief. However, until recently, grief has never been the focus of research. Marc Bekoff, a scientist, has spent his time researching emotions in animals, including grief. Combined with other research, the following animals have been seen to grieve: wolves, chimpanzees, magpies, elephants, dolphins, otters, geese, sea lions, and many more.

What is Animal Pain?Edit

Bernard E. Rollin says that the ability to experience pain is something we have to feel to be considered moral (Rollin, 2010). It can result from something such as a wound or abuse causing physical pain. Animals can also experience pain mentally, such as experiencing grief as well as sadness due to anxiety. Animal pain can be understood once we understand the nature of a certain animal.[1] For example, when somebody is caring for a dog as a pet the individual understands their actions, their traits and emotions. While taking care of an animal we are then able to understand that specific animal and their way of grieving or their happiness per se.[1]

The difference in pain from humans and animals is how one is willing to bear pain for a better lifestyle. Rollin mentions an example of extending life. This example states that the owner may think pain will be a small price to pay for the life of their pet.[1] Since an animal cannot express their pain or how much something may hurt these emotions or decisions are hard to conclude. Pain felt can sometimes be unbearable to the point where humans have the decision or thought to choose death over the continuation of that pain.[1]

Animal EmotionsEdit

A question that is asked is if animals have any emotions? Marc Bekoff defines emotion as something that helps behavioral control and management (Bekoff, 2000).[2] It is known that humans have emotions and that it is something fundamental and important in our lives, however it is hard to say if that is true for animals or just some. There are different ways you can tell the emotion of animal: how they're acting or how they're looking at someone or something.

Primary Emotions and Secondary EmotionsEdit

There are different “categories” of emotions known as primary and secondary emotions. Bekoff explains that primary emotions are similar to reflex or something along the lines of fear or fight-or-flight response. Therefore, it is something that animals react to such as loud noises, unknown objects, or odors (Bekoff, 2000).[2] Having primary emotions is crucial because reactions to these are important for an animal's survival. The part of the brain that is responsible for primary emotions is the limbic system (Bekoff, 2000).[2]

Secondary emotions are part of an experience. These emotions are taking part in the central cortex of the brain because of the requirement of different and higher brain centers. With secondary emotions it allows one (in this case the animals that do feel grief) to create the connection between feelings and actions.

Early Research on Animal GriefEdit

In 1879, Arthur E. Brown studied how a male chimpanzee reacted after the death of his female counterpart. He saw the male chimpanzee display grief and "a cry which the keeper of the animals assures [Brown] he had never heard before").[3] Continuing to the next day, the chimpanzee sulked and barely moved. Brown deciphered that the male chimpanzee was depressed after the female chimpanzee died. However, Brown concluded that any permanent grief is only found in man, as the chimpanzee seemed fine after a couple of days.

William E. Ritter (1925) connects animal and human emotion to provide evidence of human descent from the animal kingdom. He mentions the James-Lange theory, where "all emotional stages as of joy, grief, fear, anger, jealousy, love, are associated with more or less characteristic bodily manifestation".[4] Ritter proposes new evidence to the theory, mentioning that no item on the above list is exclusive to humans, and most are common to the animal world. He argues that because the connection between human emotion and animal emotion is so strong, humans have descended from the animal kingdom.

Marc Bekoff's Recent Research on Animal GriefEdit

Marc Bekoff is a professor of ecology and evolutionary biology at the University of Colorado-Boulder. He has spent his life studying animals and their emotions, finding that animals grieve quite frequently. Such examples of grieving animals are:

  • Bekoff found that sea lion mothers squeal eerily when they watch their babies being eaten by killer whales.[5]
  • Even after their calves have died, dolphin mothers have been seen to save them and grieve when they confirm the death.[5]
  • Elephants have been "observed to stand guard over a stillborn baby for days with their head and ears hanging down". Orphan elephants, who have watched their mothers be killed, have been shown to wake up screaming.[5] Elephants are known to communally recognize a deceased relative similar to how they greet a newborn, by collectively touching it's corpse or old bones and possibly wailing.
  • A wolf "sniffed [her dead companion], then sat back and gave the most soulful and heart-wrenching howl I've ever heard!"; After a pack member died, the wolves let their tails and heads hang low while walking slowly.[2]
  • Chimpanzee orphans can die while in the state of grieving.[2] Jane Goodall (1990) followed Flint, a chimpanzee, for a few days after the death of Flint's friend Flo. She noted that Flint "walked along one of the branches, then stopped and stood motionless, staring down at an empty nest". Flint had been lethargic, even refusing food. Per Goodall, Flint was "hollow-eyed, gaunt and utterly depressed".[6]
  • Magpies have been seen to mourn over their dead.[7]
  • After a fellow goose died, Konrad Lorenz noted that other geese had their "eyes sink deep into their sockets, and the individual ha[d] an overall drooping experience, literally letting the head hang".[8]

[2] The previous example shows that animals can express their grief and it is possible for an individual to identify that. Bekoff mentions an experience of a bird that lost its partner. It showed many signs of depression before it ended up passing away in a vegetative state similar to the one his partner ended up dying in (Bekoff, 2010). Many animals can show grief when they have lost a loved one of their own.

How Long Do Animals Feel Grief?Edit

One of the questions that can be asked aside from do animals grieve is how long do they grieve for or if these animals show signs of mourning. Anthropologist Barbra J King mentions how animals might sleep less or change their ways in their daily life styles. These animals might also end up staying close to their companion's corpse for a long time as well (Safina, 2015).[9] Something we know is that emotions in a human can change, one day they can be sad and the other happy. Actions are taken days after one of our loved ones dies, such as time off school, work or any social interaction (Safina, 2015).[9] It is actually the same for animals. An example that can be shown is in chimpanzees.

A case is shown with one named Amos. The day before he died he spent the day in his nest and did not move until a female chimpanzee Daisy went up to him (Safina, 2015).[9] When Amos died, one of the chimpanzees who was more sociable than the rest as well as a “higher rank” than the rest did not want to be with the group for weeks. As shown here it also depends on who passed away on how long an animal can grieve. Though through the time spent mourning many signs can appear of an animals grief and agony of the loss of their companion.

Another example mentioned is the dog Hachiko from Tokyo. In this case the dog was not grieving due to the death of an animal, but of the loss of its owner. It is known that this dog went to the station where his owner would come home to every day for around ten years.

Other Research on Animal GriefEdit

Though Bekoff is the face of recent research on animal grief the field is slowly developing. Some studies have looked into depression in animals, with Paul Willner finding that there are eighteen animal models of depression.[10] Peter J. Fashing & Nga Nguyen (2012) found that a group of chimpanzees groomed and caressed a grieving, older chimpanzee. They also found that "the dying female [elephant] was approached by the matriarch of another group who repeatedly attempted to bring her to her feet using her tusks". Even otters grieve, where members of a group caught fish for months and brought them to the matriarch who had failing vision and poor mobility.[11]

Animal MourningEdit

In social groups, bereavement is a natural stress reaction in the event of the loss of a significant loved one through death.[12] Like Humans, social animal species are affected by the loss of one of their own and can undergo psychological stress or trauma.[13]

The behaviour that these social groups expect following bereavement is referred to as mourning: the act of sorrowing during a period of time during which signs of grief are shown.[12][14]

Ample research in fields of biology, animal behaviour, evolutionary and ecological biology, cognitive ethology, and neuroscience has shown that animals have brains and minds, used, like in Humans, for thinking and feeling.[15] As such they show moods and emotions and therefore grief and empathy.[15] However, our understanding of the putative emotional responses to loss of animals is limited by communication capabilities and possible differences between our psychological responses to death and theirs.[16] Thanatology used to refer to the "academic and often scientific study of death in human beings". It has now been broaden to include the study of the mechanism, body changes, but also the psychological and social consequences of death among other species.[13]

Social emotions shared in mammalsEdit

Primitive tendencies to nurturance probably evolved before the divergence of mammalian and avian stock from their common ancestor. For instance, recent paleontological evidence suggests that some dinosaurs may have also exhibited maternal care.[15] However maternal devotion, and complex social feelings in mammals are sure to have emerged with the evolution of the limbic system.[15] One of the greatest advances in the evolution of emotionality was the ability of the young to value social support. Jaak Panksepp says that this is achieved by a separation-distress or PANIC system, which is a sensitive emotional barometer that keeps track of the level of social support they are receiving. When social contact is lost, organisms experience the painful feeling of separation, and the young reacts vigorously in an attempt to reestablish contact and care.[17][15]

Scientists documenting social animals nurturant behaviour towards dead young explain it by the species gregarious nature.[18][19] These species strongly rely on cooperation and social bonding, including allomothering,[20][19] explaining such actions as adults taking care of other parent's calves and even adoption.[21][19] Human infants are born with brains that are about 23 percent of their final capacity, characteristic that neuroanatomists explain by the yet need to learn.[15] This case is similar in some species, such as in elephants[15] or odontocetes,[22][21] and these exhibit long periods of infant dependency and thus substantial nurturant behaviours in mothers.[21] Fred B. Bercovitch states that among female mammals, lifetime reproductive success depends upon rearing, more than on production of offsprings,[23] which is associated with the strong maternal-infant bond.[23] He then proposes that oxytocin's role in this mother-infant bond might have evolved to be implicated in promotion of social bonds as well. This intricate connection between physiology and behaviour may allow the rationale for the care and carrying of deceased newborns found behaviour, in group-living species.[13][23]

Mourning animalsEdit

ElephantsEdit

Elephants are a highly cognitively and emotionally engaged animal.[15][24] “Through observational evidence they seem to have a real unusual interest in the dead of their own species either fresh carcasses or skulls. [...] and the interest seems to persist long after death” - says Karen McComb, co-director of the Mammal Vocal Communication and Cognition Research Group at the University of Sussex. She is a behavioural ecologist and an expert in analyzing vocalizations of mammals to assessing thoughts and emotions.[15][25] For that, McComb studies 'contact calls', powerful rumbles elephant use to keep in contact for large distances, and plays recordings of these to approaching herds of elephants while observing their reaction to them. These are her clues in her study. When played the call of a missing family member, the elephants were seen running trumpeting towards the speaker, as if they had someone in ‘mind’ they expected to see.[15] She also used the call of a fifteen-year-old female elephant who had died, and played it twice to her family, once a few months after her death and then twenty-three month later. Similarly, the herd ran to her rumbling in greeting, walking directly to the speaker. “They hadn't forgotten her. [...] But I was uneasy doing that test.” - she mentions.[15] Elephants have intensive social natures and retain their memories for many years.[26] They have the adequate neural anatomy for long-term memory: their brains have large and complex frontal lobes, important structures for storing and retrieving memories of scent, touch, smell, and sound.[15] Poachers often target the matriarchs or older females of the group because they have larger tusks. This is an impactful loss for the group because they lose a lifetime of learning and knowledge.[15]

Elephants have a concept of death. For instance, they recognize carcasses and skeletons of their own kind as well as of others.[27][15] McComb performed experiments in which she placed skulls of elephants killed by poacher, to make miniature elephant graveyards, in the path of approaching herds. She observed that they took a real interest in skulls and bones of their own kind, touching and investigating the body for hours.[25] The behaviour they adopt when encountering their dead relatives varies, says Cynthia Moss, ethologist and director of the Amboseli Elephant Research Project, and who invited McCom to join her team. “They stop and become quiet and tense in a different way from anything I have seen in other situations”.[15] Responses of elephants to conspecific carcasses at various stages post-mortem has been intensively documented.[26][28] They display touching behaviours such as smelling and caressing the remaining body with their hind feet or with their trunk. Initially, the dead might be treated as if it was still alive, or unable to move as if injured. It gets carried in order to keep up with the group, tried to be lift up and help stand. Such actions reveal the elephant's empathetic and compassionate nature [15] and shows that they do not want to abandon the deceased individual.[23] They have been seen to cover bodies with nearby vegetation, as a burial.[26] Out of many others, Sharma [29] described a case of an adult female mother in southern India, standing around her dead calf for weeks. The mother later watched from a distance a veterinary team conducting an autopsy on-site and remained around 100m away from the fire on which the calf's body was cremated.[26][29]

There are tales about elephant's graveyards.[26][15] These are believed to be places where dying elephants direct themselves to die with their conspecifics. Today it is believed that these are actually the remainder bones and skeletons of elephants killed by poachers. However, some reports allow the hypothesis that elephants, which are always on the move, may return occasionally to places where a member has been buried.

CetaceansEdit

Many studies reviewed reports of whales and odontocetes, dolphins in particular, displaying nurturant behaviours towards dead calves and juveniles, either by supporting or carrying the young at the surface for very long distances and for a very long time.[19]

One example of the many cases Reggente [19] reports in their study describes an adult Risso's dolphin interacting with a dead calf. Observers related the animal swimming holding on its back the young dead by its dorsal fin, then swimming in circles under the carcass, touching it with several parts of its body (rostrum, and pectoral and dorsal fin), and remaining in vertical position next to the dead calf.[19] Later, the adult pushed the body away from its observers, who did not attempt to follow them. Another reports an adult Indo-Pacific bottlenose dolphin pushing a small dead dolphin across waters. Biologists decided to fix a rope and drag the carcass to the shore to bury it. Observers report having the adult following it, touching it and swimming around until it reached shallow waters.[19] In one study, Kilborn (1994)[30] reported a case in Point Defiance Zoo and Aquarium's whale exhibit, in which a captive mother beluga whale, Mauyak, gave birth to a male calf which died right after birth. After delivering the placenta a few hours later, she took it in her mouth and moved out of reach from the staff, carrying it for hours before it was removed from the pool. The day after, she was found carrying a 30-cm diameter pink buoy that had been available to her prior to the birth.[30] Many testimonies also report seeing killer whales carrying dead calves for miles.

Smith and Sleno (1986),[31] and Kilborn (1994)[30] allow the hypothesis that these recurrent nurturant behaviours found in the wild might be due from the incapacity of the mothers to accept their infants' death.

Non-human PrimatesEdit

Specialist Jane Goodall recognizes that chimpanzees have distinct personalities that impact their success in life.[15] As the animals discussed previously and still many others, they show sophisticated behaviours: they forge friendship, communicate, have a sense of fairness, occasionally deceive and lie, and grieve for their dead.[25]

Concerning great apes, the best known reports until today probably account Goodall's descriptions of chimpanzee mothers carrying and caring for dead infants,[32] as well as reports from Geza Teleki on a group's response to an accidental adult chimpanzee's fatal fall from a tree.[33][13] Anderson et al.[34] report was the first to include video evidence of chimpanzees' precise moment response at the death of an elderly female of their group.[13] They could draw parallels with behaviours seen in humans in such circumstances, such as pre-death care of the female, close inspection and testing for signs of life at the moment of death, male aggression towards the corpse, all-night attendance by the deceased's adult daughter, cleaning the corpse, and later avoidance of the place where the death occurred.[34]

In humans, expressions of sympathy and moral support may arise towards the family members in the event of a relative's death.[13] Goldsborough [35] observed captive chimpanzees' affiliative interactions with an adult female before and after the birth of her stillborn baby. She received more affiliation than before, including from previously non-affiliative chimpanzees, and particularly from a female who also had a stillborn infant in the years before her.[9]

GiraffesEdit

In Giraffes, the mother-infant bond that happens during the neonatal period lasts for a minimum of 12-16 months [36] and there are suggestions that mother and daughters may associate for several years and more.[37] Giraffe's calves have high mortality rate (58-73%)[38] in the first year and literature shows mothers adopt a characteristic nurturant behaviour in the event of their calf's death. Cases have described behaviours of mothers standing guard over their newborn dead calves,[23] while giraffes rarely remain stationary for long,[23] or of mothers watching quietly from distance their infant carcasses being fed on by predators.[26]

Laysan albatrossesEdit

Laysan albatrosses are monogamous. They don't breed until they are eight or nine years old. John Klavitter is a U.S fish and Wildlife Service biologist at Midway and says that when an albatross loses one of their mate the surviving bird “goes through a year or two of a mourning period” before it starts searching again for a new mate, a process that can take many years.[15]

Mute swansEdit

Mute swans, Cygnus olor, are monogamous, and are known to go through a mourning period[39] following the death or loss of their mate or a cygnet.[40] Should a parent die while there are cygnets present, the remaining adult will take up its counterpart's duties in caring for the offspring. After undertaking the mourning period, the surviving swan, if it is alone, may remain in the area or depart to locate a nearby flock.

Other animalsEdit

In human management systems, such as in parks, farms and laboratory animals, animals are subject to abrupt separation from their mothers[41] and other conspecifics.[42][16] McGraph [16] addresses the abundant scientific findings about grief and separation distress that are found in domesticated animals such as cows, pigs, sheep, goats, horses and chickens. Physiological changes resulting from it include distress vocalizations, increased activity or locomotion, escape attempts, increased heart-rate and increased hypothalamic-pituitary activity.[16] They do not show sign of the bi-phasic protest-despair reaction typical of grief.[16] Nonetheless, this does not mean that they are not capable of grieving as some may present other reactions. This assumption raises issues and debates about ethics and welfare of animals in situations such as with laboratory animal management.

William Russel and Rex Burch published the seminal book, The Principles of Humane Experimental Techniques,[43] and introduced the now referred "3Rs" principles: reduction, refinement and replacement of animal use. Despite the attention brought to this issue by the authors and since, the number of animals used in research and testing continues to increase drastically.[44]

Marc Bekoff is a former Professor of Ecology and Evolutionary Biology at the University of Colorado, and co-founder with Jane Goodall of Ethologists for the Ethical Treatment of Animals.[45] He supports that animals have emotions, empathy and moral intelligence, a theory that has been extensively supported by scientific proofs.[46] In his ample work, some of his reports include cases of grieving animals. Among others: magpies standing next to a conspecific's corpse, gently pecking at it, seems to be a ritual that has been observed in ravens and crows as well; baboons; elephants [46].

Human grief from pet-lossEdit

Some examples of empathy cross the species barrier. One is the famous dog-human relationship.

The process of grief over the death of a pet among owners is under-explored in research and often devalued, but some studies have tackled on comprehensive analysis of grief responses in dog owners, showing that the more the owner has the tendency to humanize his animal the more intense the grief experienced will be.[12] In consequence, the mourning behaviour will be similar to ones that he would have if he went through the loss of a human companion: burials, cremations, taxidermies. These mourning rituals similarly allow owners to recapture and re-experience intensely lived moments of comradeship and closeness with their fellow companion.[47] When the pet may have played an additional role such as being a working dog, service or therapy animal, owners will not only grieve the loss of a companion but also the loss of a co-worker.

Pet cemeteries exist. One is the Psi Los (“Dog's fate”) cemetery located in Konik Nowy, on the outskirts of the Polish capital city of Warsaw. There, the place is home to thousands of animal graves and tombstones, including numerous species: dogs, but also cats, rats, rabbits, guinea pigs, hamsters, mice, ferrets, chinchillas, canary birds, turtles, and at least one iguana. In social practices, significant similarities can be observed in ways to commemorate companion animals to those typically found in human cemeteries in Poland: families paying a visit, lighting candles, placing fresh or artificial flowers. Moreover, at Psi Los, the Catholic All Saint's celebration is mirrored on the same day (November 1st) by the informal Pet Memorial day.[48]

Implications of ResearchEdit

Though grief in animals may seem questionable, evidence shows it is abundant. From chimpanzees to otters to sea lions, animals grieve just like humans do. Researchers like Bekoff, Fashing, Nguyen, and others, are studying every day to help better understand how and why animals grieve. With increased knowledge, humans can have better relationships with animals. For example, zoo caretakers can study chimpanzee grief habits and better notice when a chimpanzee mother is mourning. The caretakers can then help the mother cope and live a healthy and successful life. Research shows grief in animals, and understanding that can help humans form closer, healthier connections with them.

ReferencesEdit

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