Cognition in Tamarins and Marmosets, Special Topic by Intern Audra

As much of primate cognitive research is conducted with the goal of determining the development of cognition in humans, a majority of the information available is regarding Old World Monkeys and Apes, as they are more closely related to humans. Because of this, there is a disparity in the amount of cognitive research conducted on New World monkeys, such as Marmosets and Tamarins, due to the unfounded assumption that these species are intrinsically more primitive because of their relatively small brain size. In fact, recent evidence has uncovered that Callitrichid species indeed advance cognitively, and actually possess and display a vast array of adaptive behaviors in response to environmental and social cues alike.

The advances observed in primate cognition are partially explained by the possession of hands, which allow grasping behaviors that permit a vaster range of food sources, and thus a larger repertoire of foraging behaviors. Not only does this involve the necessity of identifying and processing a wider variety of food types, but also the requirement of extracting food supplies from more complex sources, like cracking open nuts. Because of this reliance on varying food sources, more advanced spatial cognition is required in order to recall where these sources are found. According to field studies, food supplies are not found in the wild by chance, but rather by direct routes taken from one source to the next. This information indicates that these monkeys must possess a complex mental representation of their forest habitat in order to forage so efficiently. 

Studies have also shown that Marmosets and Tamarins show advanced cognitive capacities in their ability to display object permanence–the awareness that an object continues to exist despite being out of sight. This is an ability that human children begin to develop at about six months of age. One study conducted on Tamarins found that in a situation involving brief exposure to tasks and foraging opportunities, Tamarins readily expressed the ability to track objects' movements and respond flexibly. In another study, Marmosets were able to locate food rewards which they watched being hidden under various objects, even when these objects were relocated. This ability to display object permanence is just another reminder that while they may not have the same cognitive functioning as humans, there are so many minute ways in which we are cognitively similar.

Social pressures are also thought to play a large role in the advances seen in primate cognition. Not only does the cooperation learned from working within and between groups to find food permit a higher abundance of resources, but it also allows a higher scale of protection to be afforded against predators. This is particularly common among Callitrichids, who are seen to have a uniquely high aptitude for cooperation. Many other primates commonly exhibit regular food aggression toward group members and outsiders, however, Callitrichids do not display these behaviors commonly. Furthermore, as there are generally only two breeding individuals in a group, the other group members are able to help in rearing the offspring. This is another uncommon behavior exhibited by Callitrichids that characterizes their high levels of cooperation, and thus, the vast intricacies of their cognitive abilities. 

At PPS, it is no surprise to the caretakers that these individuals possess advanced cognitive abilities. Due to the garden and orchard maintained on site, the monkeys in our care experience seasonal changes in the foods provided to them, much like they would encounter in the wild. The individuals are seemingly able to recall food items, and appear to have memories of favored foods, as they are heard excitedly chirping upon being presented with a preferred item they haven’t had since the last time it was in season. Additionally, the monkeys sometimes seem somewhat perplexed and surprised when a familiar food item is presented in a manner they do not expect, such as receiving a frozen piece of banana on a sunny day. Caretakers at PPS are fortunate enough to be able to witness innumerable behaviors such as these every day, which serve as daily reminders as to how truly similar we are.

References:

·       Ford, S.M. The Smallest Anthropoids: The Marmoset/Callimico Radiation. New York: 

Springer Science, 2009.

·       Neiworth, J.J. ; Steinmark, E.; Basile, B. M.; Wonders, R.; Steely, F.; DeHart, C. A test of object 

permanence in new-world monkey species, cotton top tamarins (Saguinus oedipus). PubMed, 2003.

·       Rylands, A.B. Marmosets and Tamarins: Systematics, Behaviour, and Ecology. New 

York: Oxford University Press, 1993.

·       Strier, Karen B. Primate Behavioral Ecology. Upper Saddle River, N.J: Prentice Hall, 2011. 

·       Sussman, R.W. Primate Ecology and Social Structure. Pearson Custom Publishing, 2003.

Social Traditions in Capuchin

The immersion Internship at Pacific Primate Sanctuary (PPS) provides Interns with an opportunity to expand their knowledge of New World Primate species, both through hands-on experience as well as making use of educational resources. The monthly Talk Story- Special Topic encourages Interns to gain a more in depth understanding of each of the species here at PPS.  Following is a Special Topic written by Intern Owen.

Intern Owen: Special Topic

A social tradition is defined as a “behavioral practice that is relatively long-lasting and shared among members of a group, each new practitioner of the behavior relying to some extent upon social influence to learn to perform the behavior”. Some of these traditions may work to increase foraging success or strengthen social bonds, but some have no clear evolutionary purpose at all.  A group of 10 capuchin field researchers worked together to identify and understand social traditions in capuchins. They focused on 4 different research sites in Costa Rica (Santa Rosa National Park, Lomas Barbudal Biological Reserve, Palo Verde National Park, Curu Biological Reserve), which contained capuchin groups that were geographically and ecologically similar enough to suggest little genetic difference. This allowed them to delve into the development and social transmission of these unique behaviors. 

The traditions were identified and classified based on the following 3 criteria:

1.     The behavior must occur at least once per 100 hours in one or more group and be absent in other groups to be considered common, once per 250 hours to be rare.

2.     The behavior must be observed to spread through a social network.

3.     The behavior must continue being displayed for at least 6 months.

In the Lomas Barbudal Biological Reserve, 5 social traditions were observed over a 13-year period: Hand-sniffing, Eyeball-poking, Sucking of body parts, Hair-in-mouth Game, and Toy Game.

Hand-sniffing was observed to have 2 variations: 1) the hand of one individual is wrapped around the nose and mouth of another; 2) the fingers of one individuals are inserted into the nostrils of another. The participants performing the behavior would maintain the position for several minutes, often swaying as they sniffed. This was commonly observed to be a mutual behavior in which both participants would be Hand-sniffing each other. This tradition was common in 4/7 groups, rare in 1/7, and absent in 2/7.

Eyeball-poking involves one individual inserting a finger between another’s eyelid and eyeball, up to as deep as the first knuckle. The participants usually maintain the behavior for several minutes, but some sessions have been observed to last up to an hour. If the finger falls from the eye it is often reinserted. It was observed that the recipient of the Eyeball-poking would often insert a finger into the actor’s mouth or nostrils during the process. This tradition was common in 0/7 groups, rare in 4/7 groups, and absent in 3/7.

Sucking of body parts involves one participant inserting some body part of another participant (tail, finger, ear etc.) into its mouth and sucking for several minutes. Both participants often mutually perform this behavior; especially in cases when the tail tip is the body part being sucked. Participants are often slightly apart from the rest of the group, relaxed, and groom each other before performing this behavior. This tradition was common in 2/7 groups, rare in 3/7 groups, and absent in 2/7 groups.

Hair-in-mouth Game involves one participant biting hair from the face or upper body of another. The other participant may flinch, but then will try and retrieve the hair by attempting to open the mouth of the partner. If successful, the hair is then passed between the partners’ mouths until the majority of it has fallen to the ground. If one participant begins to lose interest, the other may open his or her mouth to show how much hair remains. This tradition was common in 2/7 groups, rare in 1/7, and absent in 4/7 groups.

Toy Game functions in much the same manner as the Hair-in-mouth Game, except an inanimate object is used instead of hair. This object is often a stick, a leaf, or a piece of bark. As with the Hair-in-mouth Game, the toy is never consumed, but transferred between each participant’s mouths until it falls to the ground. This tradition was common in 2/7 groups, rare in 1/7, and absent in 4/7.

These traditions show no evidence of evolutionary advantage – some even seem to pose high risk to the participants. However, they persist for a significant duration of time; anywhere from 6 months to 10 years. It is theorized that these behaviors exist in a similar way to human fashion trends; they arise, socially transmit and then fade, without any significant effect on survival or reproduction. These trends, however, may work as a mechanism for social bonding that can reduce conflict and increase cohesion as a group. They may help solidify alliances, reduce stress, or even be a symptom of social learning. Either way, social traditions in capuchins are fascinating. 

At PPS, we see the resident capuchins, Miracle and Prospero, displaying unique behaviors that could be social traditions. One example is when they gather small rocks onto their platforms and arrange them into different orders. There is no clear evolutionary benefit to this behavior, and yet it persists. It mainly occurs during early mornings before they have been fed, suggesting this tradition may function as a process that occupies them until their food arrives. As capuchins naturally combine substrates and are extractive foragers, this type of behavior may be an immersive game to them. The highly social nature of capuchins, combined with their high cognitive functioning, results in a variety of unique and quirky traditions to occur – just like in us humans.

References:

·       Balter, M. "Probing Culture's Secrets, From Capuchins To Children". Science, vol 329, no. 5989, 2010, pp. 266-267. American Association For The Advancement Of Science (AAAS), doi:10.1126/science.329.5989.266.

·       Fragaszy, Dorothy M et al. The Complete Capuchin. Cambridge University Press, 2004.

·       Perry, Susan. "Social Traditions And Social Learning In Capuchin Monkeys (Cebus)". Philosophical Transactions Of The Royal Society B: Biological Sciences, vol 366, no. 1567, 2011, pp. 988-996. The Royal Society, doi:10.1098/rstb.2010.0317.

·       "Wild Capuchin Foundation". Capuchinfoundation.Org, 2020, https://capuchinfoundation.org/.

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Intricate Whinny

The immersion Internship at Pacific Primate Sanctuary (PPS) provides Interns with an opportunity to expand their knowledge of New World Primate species, both through hands-on experience as well as making use of educational resources. The monthly Talk Story- Special Topic encourages Interns to gain a more in depth understanding of each of the species here at PPS.  Following is a Special Topic written by Intern Clara

Intern Clara: Special Topic

When approaching Carlos and Montana’s Enclosure, you can hear them making a high-pitched vocalization called a whinny. It is one of the most common vocalizations we hear at the Sanctuary, and it is a friendly interaction. In the wild, a spider monkey can hear the call of another of its troop members as far as 900 feet away. 

The essence of the whinny can be explained by spider monkey behavioral ecology and ranging patterns. They feed mainly on ripe fruits, which are rare in the forest compared to other sources of food, such as leaves. Thus, spider monkeys have adapted to reduce food competition in the group and, in doing so, increase the likelihood of survival. To do so, they live in fission-fusion societies which means that troops split up during the day into subgroups. This process aims at reducing food competition between the different members by spreading far away from each other while foraging in the rainforest. To maintain their social cohesion and communication, they developed long-distance calls. The whinny is one of them. 

Changes in frequency within one whinny call allows the sharing of information, even if individuals are far away from each other. Indeed, the “abrupt changes in fundamental frequency” (Campbell, 2008) allow the call to be distinctive, even if the canopy acts as a noise buffer. It is also hypothesized that they can recognize each other based on the frequency, modulations, duration and number of elements of their call, in a similar way that humans can recognize each other by hearing voice alone. But what is the purpose and information carried out by a whinny? One hypothesis is that it is used to indicate food availability to other subgroups foraging for food. In a study on Ateles geoffroyi in Costa Rica, it was observed that spider monkeys were more likely to whinny if there was more food available in their food patch. The number of calls emitted also impacted the likelihood of other subgroups joining the food patch; the more calls emitted, the more likely other members were to join.  This is regularly observed at PPS, as Carlos and Montana both whinny frequently when they receive their breakfast bowls each morning, likely letting one another know that food is abundant. 

Another hypothesis is that the whinny maintains contact between individuals when they cannot see each other. A  different study on Ateles geoffroyi, in Mexico, showed that the receiver of the call was more likely to approach the emitter if they were close to each other socially (if they have a strong bond or know each other well). One possibility is that the call could solely communicate information about the emitter’s identity and that the receivers respond according to their mutual relationships.  At PPS, we can assess when Carlos and Montana gain comfort with a new caregiver, as they will start to whinny at their caregivers more frequently when they know them better.  This can help us determine when a new caregiver should start to feed Carlos and Montana, or hose their Enclosure. 

Contrary to alarm calls that generate direct actions from the recipient, there is a great variation in the response of other group members when hearing a whinny. In some cases, the recipient(s) of the call will whinny back or take a particular action. In others, there will be neither vocal nor physical response. This makes the whinny hard to interpret and to explain. Based on the analysis of the call itself, it is almost certain that the individuals have distinctive calls that are recognized by other troop members. This generates different responses based on the context and the relationship the receivers have to the emitter.

Reference cited

·       Campbell, J. Spider Monkey: Behavior, Ecology and Evolution of the Genus Ateles. Cambridge University Press, 2008.

Chimerism in Callitrichids

The immersion Internship at Pacific Primate Sanctuary (PPS) provides Interns with an opportunity to expand their knowledge of New World Primate species, both through hands-on experience as well as making use of educational resources. The monthly Talk Story- Special Topic encourages Interns to gain a more in depth understanding of each of the species here at PPS.  Following is a Special Topic written by Intern Holly.

 Special Topic by Intern Holly

Genetic chimerism occurs when an organism has cells that are genetically distinct from one another. This organism may have blood cells of differing blood types, or two differently-colored eyes, or they may even have a mix of male and female reproductive organs. In most animals, chimerism develops when multiple fertilized eggs merge together while in utero, creating a single organism with multiple cells that are different from rest of the body’s genetic structure; thus, chimerism is often the result of a zygote absorbing their twin. Chimerism can also occur in plants, but the chimera is often the result of a mutation during cell division, rather than two early-developed organisms merging together.

All species of Callitrichidae, aside from the Goeldi’s marmoset (Callimico goeldii), routinely give birth to fraternal twins. Early in development, the placentas of the twin embryos fuse together. This placental fusion allows the twins to exchange stem cells, specifically germ cells and hematopoietic cells. Germs cells are the cells that will give rise to gametes (ovum and sperm) in reproductive organs, while hematopoietic cells will become blood cells. These mixed hematopoietic cells can be found in blood, bone marrow, and internal organs, which means that every tamarin and marmoset is a composite of cells from multiple individuals: a chimera. 

Callitrichids also routinely engage in germline chimerism, a trait that is unique to them specifically due to its regular occurrence, rather than by chance. As mentioned, germ cells will become gametes, the cells that an organism uses to reproduce. During cell exchange through the fused placenta the twins’ germ cells exchange alleles. Alleles are the expressed variants of genes, i.e.: whether an animal will have blue or green eyes. Not only is every tamarin and marmoset a chimera, they also carry reproductive alleles of their fraternal twin, in addition to their own. 

One implication of germline chimerism is that a tamarin or marmoset could sire or give birth to offspring that are more genetically related to their twin than to them. Evidence suggests that chimerism is a contributor for the cooperative breeding system found in Callitrichids. In a cooperative breeding system, all members of a family group help care for offspring, not just parents. Personal reproductive fitness is the number of offspring that an individual bears, while inclusive reproductive fitness is the number of offspring equivalents that an individual raises. The non-reproducing “helpers” in a cooperative breeding system are engaging in inclusive fitness: by taking care of their siblings or nieces/nephews, they are ensuring that their family line lives on, even if they do not reproduce themselves. Due to germline chimerism and the resulting interrelatedness of the family group, it becomes very important for a tamarin or marmoset to help care for their siblings/niece/nephew, because that offspring may actually be more closely related to them than to their biological parents. 

Many of the tamarins and marmosets at Pacific Primate Sanctuary come from the same family groups. With the knowledge of chimerism, it becomes evident that the level of interrelatedness is more complicated than a standard family tree diagram would suggest. When attempting to pair a male and female, we have had the most success with pairing two completely unrelated individuals. Not only does this kind of pairing have the most resemblance to wild Callitrichid breeding pairs, but it is possible that tamarins and marmosets may recognize family traits, even in an individual they have never met before, and prefer not to partner with a closely related individual, although, more evidence is needed to support this hypothesis. (Male Callitrichids at PPS have been vasectomized.)

References

• Rutherford, J. N. & Tardif, S. “Mother’s Little Helper? The Placenta and Its Role in Intrauterine Maternal Investment in the Common Marmoset (Callithrix jacchus).” 
• The Smallest Anthropoids: The Marmoset/Callimico Radiation, edited by Susan M. Ford, Leila M. Porter, & Lesa C. Davis, Springer, 2009, pp. 301-329.

The Amazon Rainforest, here and now

The immersion Internship at Pacific Primate Sanctuary (PPS) provides Interns with an opportunity to expand their knowledge of New World Primate species, both through hands-on experience as well as making use of educational resources. The monthly Talk Story- Special Topic encourages Interns to gain a more in depth understanding of each of the species here at PPS.  Following is a Special Topic written by Intern Cookie.

Intern Cookie: Special Topic

Spanning three million square miles, constituting 30% of South America’s surface area, housing over 30% of the world’s insect, plant, and animal species, harboring a rich mosaic of tropical vegetation that each moment transpires oxygen and water, stores carbon, indiscriminately shelters vast populations and holistically provides for its contingent, the Amazon Rainforest is the cradle of the world’s biodiversity and fragile ecosystem. Why does the Amazon Rainforest play this critical role? Perhaps because nature spent millions of years implementing and refining delicate, specific, and effective practices. Practices that could (can) be capricious, arbitrary, callous at times, but also processes that were (are) dependable, self-sustaining, mechanistic, and not only account for but wholly depend upon variation. If a country were to govern and provide for its population in a similar manner, we would deem it a success. With the increasing global economic initiatives dependent on its destruction, we have deemed the Amazon rainforest a success to be exploited.

In the last 50 years, one fifth of the of the Amazon Rainforest has been slashed and burned, mostly in Brazil, whose borders contain over two thirds of the Amazon basin. More land, not accounted for by this proportion, has been fragmented and degraded. 

Why is this happening? Industrial agricultural practices, mining, logging, and cattle farming are the major contributors, but there are also other culprits in the ongoing destruction. The displacement/destruction of indigenous communities, the removal of keystone species, the construction of dams, and the expansion of urban areas also cause forest loss. Humans have proven incredibly adept at occupying any ecological niche, mostly because technology and social collaboration allows for the acquisition of resources from nature. And the Amazon Rainforest is the richest, densest repository of natural resources in the world.   

Yet even small changes to the Amazon Rainforest have a ripple effect. With the abundance of trees that store carbon in their trunks, branches, and leaves, the Amazon acts as a carbon sink. As the forest is degraded and disturbed, as it has been in recent years, carbon gains have begun to exceed carbon losses. Carbon storage negates temperature elevation on a global scale, but the release of carbon exacerbates this issue. Daily, the earth is warmed by the sun, and this heat rises into the atmosphere. Atmospheric gases, especially carbon dioxide, capture solar heat and radiate it back towards earth. More atmospheric carbon, therefore, creates higher global temperatures. As temperatures rise, the delicate tropical balance of rainy and dry seasons is disrupted, and the Amazon rainforest (as well as other forests and lands across the globe) becomes increasingly susceptible to drought and the continued loss of vegetation. While humans exploit the Amazon’s land, timber, and minerals, countless other species depend on, and symbiotically contribute to, the Rainforest’s rich and complex ecosystem. Deforestation of the Amazon is their loss, too. 

Pacific Primate Sanctuary (PPS) is home to five different primate species, all of which are endemic to the Amazon Rainforest in South and Central America. In nature, these primates serve as ecological engineers through seed dispersal, exudativory and insectivory. Due to their feeding ecology as well as their role as both predator and prey in the wild, marmosets, tamarins, capuchins, and spider monkeys represent keystone species in the Amazon biosystem. While these individual animals have found refuge at PPS, their species have nowhere else to go. Their habitat has been destroyed, and their contributions to growing, maintaining, and sustaining the Amazon Rainforest have been negated. 

Climate change, habitat loss, and elimination of biodiversity are all environmental buzzwords—buzzwords that in 2000 incited a change in Brazil’s environmental protection policies. By implementing governmental incentives to conserve Amazon lands, regulating agriculture, practicing sustainable development, and collaborating with activists and researchers, Brazil slowed the rate of forest destruction. In 2012, the country reached the lowest rate of deforestation since record-keeping began. Sadly, in 2018, the election of the country’s new president, Jair Bolsanaro, has led to the prioritization of agribusiness initiatives over conserving this massive terrestrial ecosystem. Since his election in October, environmental protection policies have been lifted and conservation efforts undermined. Recent reports have shown that even in a short time period, from October to July 2019, the rate of Rainforest destruction has exceeded 50% of the deforestation rate during the same time period last year. While Brazil was once a global leader in preservation, recent policy changes have led to a role reversal. The country’s shift from environmental protection to promoting environmental degradation suggests that the significance of conservation has been dampened and its implications ignored and overruled. As the rate of climate change, habitat loss, and biodiversity elimination accelerates, no one seems to be watching and listening.

While human actions are the root cause of the destruction and fragmentation of the Rainforest, our actions are also the only way that these practices can be halted and their effects prevented. Living in a first-world country, far removed from the vibrant web of life in the Amazon basin, it not only easy but natural to feel aloof, guiltless, and uninvolved in its systematic destruction.

Yet, we are living in an era of globalization and vast social interconnectedness. Now, more than ever, it is imperative that we also feel connected to nature, attuned to its needs and effected by its devastation. This relationship is one of mutual dependence, and we are the gatekeepers of change to our earth, our home. 

Literature Cited

-Baccini, A, et al. “Tropical Forests Are a Net Carbon Source Based on Aboveground Measurements of Gain and Loss.” Science (New York, N.Y.), vol. 358, no. 6360, 2017, pp. 230–234.

-“Brazil’s Sustainability Needs Social Sciences.” Nature Sustainability, vol. 1, no. 11, 2018, p. 607.

-Carson, Walter P., et al. Tropical Forest Community Ecology. Wiley-Blackwell Pub., 2008.

-Casado, Letícia, and Ernesto Londoño. “Under Brazil’s Far-Right Leader, Amazon Protections Slashed and Forests Fall.” New York Times, 28 July 2019.

-Link, A., and Di Fiore, A. “Seed Dispersal by Spider Monkeys and Its Importance in the Maintenance of Neotropical Rain-Forest Diversity.” Journal of Tropical Ecology, vol. 22, 2006, pp. 235–246.

-Sussman, R. W., and W. G. Kinzey. “The Ecological Role of the Callitrichidae: A Review.” American Journal of Physical Anthropology, vol. 64, no. 4, 1984, pp. 419–449.

Primate Update June 2019

Facial Displays in White-Faced Capuchins
Special Topic: Intern Cookie

Capuchin monkeys are highly social animals who live in groups. Communication is important in social living, as signaling between monkeys helps establish rank, and social relationships help create and maintain group cohesion. Capuchins utilize several different modes of communication. While researchers have identified, and documented visual, vocal, tactile, and olfactory modes, there are likely other forms of signaling between capuchins, (i.e. pheromonal signaling) that we as humans are not aware of, as communication can take many forms.

One important mode in which capuchins provide information about their internal state is through facial expressions. Capuchins have highly developed control of their facial musculature as well as a keen ability to visually detect and differentiate between the facial expressions of other conspecifics. These traits likely evolved together, forming the ability to both send and interpret visual signals. Facial expressions ultimately facilitate complex communication between group members. As caregivers for Miracle and Prospero, the white-faced capuchins at Pacific Primate Sanctuary (PPS), we are often on the receiving end of these facial displays. Knowledge about capuchin facial expressions and their communicative function can help us understand Miracle and Prospero’s internal state and best accommodate their needs at PPS.

As with any type of social signaling, the meaning of capuchin facial expression is largely dependent upon the context in which it occurs. However, facial displays can be roughly characterized as conveying four different types of communicative function: affiliative intent, play intent, submissive display, and agonistic intent. Further, these functions are not mutually exclusive. For example, one study by De Barco and Visalberghi (2006) found that in a social group of captive capuchins, the Silent Bared-Teeth display was used by older group members to signal affiliation and acceptance towards a new infant born into their group. Yet this display was also frequently used by young males to signal submission to the group’s alpha-male.

The following eight types of facial displays depicted below each hold a functional significance. I will elaborate on each display, providing a brief description on the facial expression as well as the contexts in which each display is most commonly used.


Neutral face effectively represents no facial expression and is a reference point for other displays. Other facial displays may involve differences (from the Neutral face) in the gaze, position of the ears, jaws, scalp, body posture, and accompanying vocalizations.

Relaxed open mouth display involves the opening of the mouth into an oval shape, as the corners of the mouth are pulled back. In this display, the upper-teeth remain covered by the lips, and the jaws appear to be gaping. This expression is commonly used when play behaviors are performed, and juveniles will use this expression when they are play fighting or chasing one another. This expression is highly reciprocal, meaning both sender and receiver will use this display when playing. The relaxed open-mouth may also signal affiliation.

Lip smacking is when the lower jaw is rhythmically lowered and raised, usually accompanied by a smacking sound. Lip-smacking is significantly associated with affiliative behaviors and will be utilized with both kin and non-kin as a friendly signal. This display is also the first facial expression that infant capuchins are capable of and will be used after the first month of life.

Open-mouth threat-face involves the wide opening of the mouth, such that the corners of the mouth are completely retracted, and the teeth (canines and incisors especially) are bared and visible to the receiver. The sender will also intensely stare at the receiver when utilizing this expression, and the eyebrows will be lowered into a frown. Open-mouth threat-face will oftentimes be accompanied by a frozen threatening body posture. This display may be directed towards external stimuli outdoors (inanimate objects sometimes) and also may be performed in social interactions to signal agonistic behaviors or aggression. This facial display has no relationship with affiliative or play behaviors.

Silent bared-teeth display involves a closed mouth; the baring of the upper and lower teeth is created by the full retraction of the mouth-corners. The eyebrows are lowered into a frown. This expression has a variety of uses and largely signals affiliation and play. Silent bared-teeth display is also used by both males and females during courtship.

Open-mouth silent bared-teeth display is visually similar to the silent bared-teeth display, but the jaws are somewhat open. The eyebrows remain neutrally positioned. In other capuchin species, this face signals submission to other group members, but in white-faced capuchins, this expression is more commonly associated with both affiliative and play behaviors.

Protruded-lip face or “duck face” is when the mouth is closed, and the lips are tensed together. The lower jaw protrudes forward, and this facial display is sometimes accompanied by dancing body movements or a mounted posture. This expression is relatively rare, and it is unclear what it may typically signify.

Tongue-out involves the opening of the mouth as the tongue protrudes forward, touching the chin. This display is performed by infants and does not seem to be performed towards other group members as a method of communication.

These facial expressions convey information about an individual’s internal state and can provide insight into social relationships. The open-mouth threat face is the only expression that signals an aggressive or agonistic context. Capuchins are highly gregarious animals, and social groups are often very cohesive with limited amounts of conflict. That capuchins’ facial displays are typically used to signal affiliation and play is reflective of their social nature. By recognizing each different type of facial display and inferring intent, we can tune-in to Miracle and Prospero’s language. As caregivers, we hope to help nurture their social relationships and respond to their social needs.

Literature Cited
•    De Marco, Arianna, and Elisabetta Visalberghi. “Facial Displays in Young Tufted Capuchin Monkeys (Cebus Apella): Appearance, Meaning, Context and Target.” Folia Primatologica, vol. 78, no. 2, 2007, pp. 118–137.
•    Fragaszy, D, et al. “The Complete Capuchin: The Biology of the Genus Cebus.” American Journal of Primatology, vol. 68, no. 4, 2006, pp. 419–424.
•    Marco, A., et al. “The Repertoire and Social Function of Facial Displays in Cebus Capucinus.” International Journal of Primatology, vol. 29, no. 2, 2008, pp. 469–486.

HAWAIIAN CULTURE, VALUES and EXPRESSIONS

Pacific Primate Sanctuary is located in Hawaii, where the indigenous people have a long history of unique customs, practices and beliefs. Ancient Hawaiians had an authentic and compelling way of viewing the world.  They held that all things are connected to one another and to the Source.  The Hawaiians consider themselves stewards of the ’Aina, this Earth, and, are responsible for caring for it, and protecting it for their children.

PPS is rooted in the traditional Hawaiian values of Malama ‘aina which means to cherish, respect and nurture the land, and Aloha no na Holoholona; to show unconditional love, kindness and compassion to all living beings. Since our inception, we have embraced traditional Hawaiian values, and have incorporated these values into all aspects of our work.  We believe that caring for the land and the animals, and returning to the value systems of native people, is vital to restoring our planet and returning it to a state of equilibrium.  In this, and ongoing issues of Primate Update, we explore traditional Hawaiian world view, perspectives, practices and expressions, and their role at PPS.

Ho’omaopopo: To understand, make plain or clear, cause to understand

Ho’omaopopo is a combination of ho’o which means causation, or to cause, and maopopo which means recognize, realize or understand.  It is the act of seeking out a deep knowledge and comprehension of something, a desire to truly understand.  According to Peter Apo, an Oahu Trustee for the Office of Hawaiian Affairs, “Ho‘omaopopo is to pay attention so as to have a clear understanding absent any confusion of what is meant.”

Animals have an astonishing ability to understand one another; animal communication includes a combination of vocalizations, facial expressions, body language, scents, taste and touch.  Some animals are even able to communicate using light (such as fireflies) or electricity (some varieties of fish).  While communication within a species is particularly complex, communication between species also occurs regularly, allowing different species to effectively understand one another.  For example, the bright coloration of a poison dart frog alerts a predator that the animal is toxic.  Diana monkeys and Campbell’s monkeys are two distinct primate species, who live in the same area in Africa.  These two species not only recognize when the other species is alarm calling, but can distinguish different types of alarm calls (is the threat a leopard, or a raptor) and will also join forces with the other species to fend off predators.

Humans have focused on developing written and spoken language, and utilize this as our primary method of communication. Human language is highly intricate and comprehensive, and allows us to communicate very effectively with one another. However, with such a strong focus on one particular method of communication, humans have a diminished capacity to comprehend body language, pheromones and other alternative forms of expression.  This has put us at a disadvantage when it comes to understanding other species, who do not speak the same language.

At Pacific Primate Sanctuary, we believe that genuinely understanding the monkeys is essential to providing them with the best possible care.  New caregivers are trained to recognize species-specific vocalizations and behaviors, along with universal indicators of comfort or distress.  Time is spent unobtrusively and intently observing the monkeys, watching and listening, to learn to tune in to their communication.  We listen to vocalization recordings, watch videos of behaviors, and read through ethograms (charts of behaviors) to enhance our understanding.

This is ho’omaopopo, actively working to understand thoroughly, so we can recognize what the monkeys are telling us. In doing so, we can perceive when an animal feels safe and comfortable in their home, and we can quickly discern if an animal feels threatened.  This information helps us to recognize if an animal is interested in a potential partner, if they are sick or hurt, or if they feel threatened by a new neighbor.  It also allows us to respond in a way that the animals understand, essentially, we try to learn to speak their language.  If an individual seems nervous, we can lower our eyes and make sure we are not smiling, since direct eye contact and showing teeth are threatening behaviors to most primates. Changing our body language helps to put the animal at ease, and allows them to feel safe. In this way, Ho’omapopo is vital to providing customized and compassionate care to the monkeys at PPS.

Resources
- Māmaka Kaiao. ʻAha Pūnana Leo , Hale Kuamoʻo, 2003.  http://wehewehe.org/?l=en. June 14, 2019.
-Apo, Peter. 2011. Peter Apo. “Hawaiian Institutions, Hawaiian Values, the Hawaiian Workplace”.  http://www.peterapo.com/hawaiian-institutions-hawaiian-values-the-hawaiian-workplace/. June 14, 2019
-2013.Kapa Kulture. “Hawaiian Word of the Day: maopopo”. https://kapakulture.com/2013/05/23/hawaiian-word-of-the-day-maopopo/. June 14, 2019.
-Lavelle, Naomi. 2017. Irish Examiner. “Appliance for Science; Can animals communicate with each other?”. https://www.irishexaminer.com/lifestyle/features/appliance-of-science-can-animals-communicate-with-each-other-460987.html. June 16, 2019
-Khan Academy.2019. “Animal Communication”. https://www.khanacademy.org/science/biology/behavioral-biology/animal-behavior/a/animal-communication. June 16, 2019.
-Bradbury, Jack and Vehrencamp, Sandra. 2019.  Encyclopaedia Britannica. “Animal Communication”. https://www.britannica.com/science/animal-communication. June 17, 2019

PPS NEWSFLASH

PPS Receives Top-Rated Nonprofit Award
Pacific Primate Sanctuary has been honored with one of the first Top-Rated Nonprofit Awards of 2019 from GreatNonprofits!

GreatNonprofits is a website designed to help people find trustworthy nonprofits through user reviews. Their mission is to help inspire and inform prospective donors and volunteers, by helping them differentiate between nonprofits; find ones that they trust, and be more confident in giving or signing up to volunteer.  They also strive to enable nonprofits, regardless of the size of their marketing budget, to harness their most authentic and most effective advertising- the stories of those they serve.

Thank you to everyone who submitted favorable reviews online, we deeply appreciate your support.  We are honored to have received this prestigious award for 5 years in a row, and cherish the kind words that have been shared about our organization.  

 Go to the Pacific Primate Sanctuary page on GreatNonprofits to read the heart-felt reviews posted about PPS, and to share your own stories. https://greatnonprofits.org/o…/pacific-primate-sanctuary-inc

Carden Academy Environmental Education Presentation
PPS offers no-cost environmental education to local schools on the subjects of endangered species, rainforest preservation, and the changing global environment. Our objective is to assist our children in becoming environmental stewards, educators and problem solvers.

The Sanctuary was recently invited to speak at Carden Academy. Operations Manager, Erin, and Primate Care Supervisor, Lauren, presented Pacific Primate Sanctuary’s Environmental Education Program for the 2nd and 3rd grade classes.  We shared information about the Sanctuary and our mission.  The students were very excited to see photos and videos of the monkeys, and were eager to participate by answering questions and sharing their ideas.  The presentation ended with Lauren reading Miranda’s Miracle, a children’s book about Miranda, a capuchin who was given refuge at PPS.  To read the virtual copies of the original children’s books: Miranda’s Miracle, Little Brothers, and Sid and Elmo, please visit the “Primate Pals” section on our website: http://www.pacificprimate.org/pals-books.htm

A few days after the presentation, we received a packet of heart-warming thank you notes from the students, below are some of their comments:

“Thank you for visiting our school. I learned so much about Pacific Primate Sanctuary.  I enjoyed the video of how you rescue monkeys and take care of them.  I am happy to know that people are rescuing these animals.  I hope you will visit again soon.”

“Your presentation was very educational.  I liked your presentation because it really opened up my eyes about how important it is to take care of the monkeys.  Pacific Primate Sanctuary is amazing, so thank you for working there.”

“Thank you for visiting our school.  When you talked about the monkeys I wanted to help.  I liked learning about monkeys.  I want to volunteer.  Please visit again soon.”

Please help Pacific Primate Sanctuary to continue educating the next generation of caregivers, environmentalists, and ecologists, by making a tax-deductible donation on our website. http://www.pacificprimate.org/help.htm

MEET the INTERNS 

Pacific Primate Sanctuary’s year- long Resident Intern Program allows for the continued education of individuals seeking to learn more about New World primate care and husbandry. Interns receive intensive training in a variety of subjects including basic animal care, emergency medical care, and facility management and oversight.

A Hui Ho to Intern Kaylee who completed her Internship in May and hopes to go to Veterinary School next year. Kaylee was a committed and compassionate Intern, who was eager to learn as much as possible during her Internship.  She took her role as an animal caregiver seriously; she recognized the importance of this responsibility and was always available to help the team in any way.  Kaylee was particularly skilled in providing Emergency Care to the primates and readily shared her knowledge with other team members. Another attribute was Kaylee’s caring nature, which was evident in her skilled and compassionate care of each individual monkey. Kaylee was meticulous, paying close attention to detail.  These vital skills helped Kaylee notice signs of illness or social distress, ensure that the Enclosures and facility were in excellent condition, as well as making certain all Records and Documents were accurate.  Because of her skills and desire to have accurate, detailed records, Kaylee was chosen to be Documentation Supervisor.  In this role, she carefully reviewed the PPS Manual documents and Medical Records, noted if any information was unclear, recommended updates and edits for accuracy and clarity.  We are so thankful for the many contributions Kaylee made during her Internship, and miss seeing her smiling face in the Sanctuary each day.

Kaylee writes: 
Graduating from anything can be a little scary. Graduating from University, generally a person’s last step before entering “the real world”, can be especially intimidating though. There is a swell of pride for completing your learning in a specific area, but it’s easy to become a little anxious, as the next step is usually something new. As I was nearing graduation this time last year, I wasn’t sure what my next step was going to be. I knew that I wanted to attend veterinary school in the future, but that I wasn’t quite prepared for it yet. My college advisor would send many emails each week about various opportunities for my major, Animal Science, although my heart didn’t feel pulled towards any of them. I had gained much experience with livestock animals from my four years at Michigan State, and I had also learned many things regarding pet species from working at veterinary clinics throughout the years, but I felt like I was missing something. One day I received an email unlike the others, this email providing information about a Primate Sanctuary in Hawaii, where, as an Intern, I could learn to become a Primary Animal Caregiver. The idea of gaining knowledge about exotic animal species, and understanding how a Sanctuary worked, seemed too good to pass up.

The PPS Resident Internship is truly unlike any other Internship. I was able to live on-site where I work, and so the Sanctuary became not only a home for the monkeys, but my home as well. Throughout my entire year at PPS, I never stopped learning. I began by learning the different diet requirements and safety procedures related to caring for the monkeys. Even within a species, each individual monkey’s diet requirements are unique and change often. As this is a Sanctuary, we treat the monkeys’ as our equals and respect their space by not having PPS be open to the public. The sole purpose of this place of peace is to provide a burden-free life for monkeys with troubled pasts. My training progressed to include Enclosure maintenance and Facility maintenance, and understanding how to balance the two.

Perhaps my favorite aspect of my training was either Emergency Care training or Volunteer training. With the Emergency Care training, I became skilled in areas that my peers in the pre-veterinary field dream of learning. What began with learning to note signs of decline in the monkeys, progressed to performing a physical exam on the monkey myself (measuring and recording their temperature, pulse/heart rate, state of mucous membranes, body condition score, hydration level, and assessing each body system as well.) I gained responsibility in administering daily medications and SubQ fluids when necessary.

For Volunteer training, I learned just as much about myself as I did about the other team members. Erin, our COO, taught me many valuable lessons this year. In today’s society, we are often taught to shy away from our weaknesses and focus on our strengths. Erin taught me that you will never get better in an area of weakness if you do not practice being uncomfortable and failing a few times. She also taught me that we ALL have weaknesses. I am a very detailed-oriented person, and this year I had a great challenge of zooming my focus out and seeing the “big picture”. I was able to note progress in myself as the months continued, and my efficiency and speed while completing shift tasks improved as well. I have learned to not see weaknesses as a downfall, but rather as an area for growth. Two other bits regarding training that I found as great life tools were realizing that people often range on a Thinker vs Feeler scale, and that they can feel appreciated in different ways. A Thinker vs Feeler scale is simply a measurement of if you lean towards having more Thinker behaviors (relying on principles and facts to make decisions) or Feeler behaviors (relying on personal concerns and people involved to make decisions). Understanding why your co-workers think or act the way they do can often improve team relations and create a more peaceful work atmosphere.

It was an amazing experience to come from a bustling, city life and learn to enjoy a simple, environmentally-friendly life, living in a Yurt in the rainforest. When I was able to strip away a lot of the superficial items that I got caught up in, I was able to realize what really mattered to me. Utilizing the Garden and Orchard for food, relying on a bicycle for transportation, and not hearing anything other than nature’s noises outside created a serene environment for both the monkeys and myself.

For my Independent Intern Project, I focused on expanding the descriptions of the 3 different Training Modules we progress through as Interns. I wove the details into a narrative to help future and current Interns better understand where their training would be going, and what exactly they would be learning. Now that my Project and time at the Sanctuary are coming to a close, it is hard to not reflect on my own training. I won’t forget the first time that I successfully crate-caught and hand-caught an individual, and how empowering it felt that we could provide their care here at the Sanctuary to reduce their stress levels and begin treatment quicker. I won’t forget the first time that I fed the spider monkeys alone and they didn’t reach out and get grabby for their bowls, and also the first time that I walked past Pacey and Macaco and they remained calm and peaceful.  These individuals have all come from troubled and confusing pasts, and to feel the moment when they finally trust you is unlike anything else. I won’t forget how great it felt to enter the Corridor during hurricane season and help close monkeys into their Front Rooms that other team members had been unable to. Most of all, I won’t forget how content the monkeys appeared in their homes. It has been said that “slob-flopping” is a positive welfare indicator rarely seen in captive populations, yet I would see monkeys exhibiting this behavior every time I did a walk-through on a warm, sunny day.

I am sad that my year-long Internship is coming to an end. I will miss each of the 40 monkeys I cared for, as every one of their personalities was unique and helped create the atmosphere at PPS. It was a hard day at the Sanctuary the day Adam passed away, as he was a monarch of PPS and quite the character. I already have a soft spot in my heart for the previous Interns and team members who have completed their time at the Sanctuary and left to help the world in other ways, and I know now that I am leaving that I will carry them and the monkeys with me always. Mahalo PPS team, past and present, and monkeys for allowing me to spend a year of my life helping you. I hope that this year of service will ingrain in me a selfless attitude that I carry for the rest of my life. I hope that I continue to view the Earth around me as magnificent and deserving of my respect, and all beings as my equal. Although I am going back to Michigan, thousands of miles away, I will always think of the Sanctuary as my ‘Ohana.

Farewell Kaylee, we hope to see you in the near future!

Introducing PPS Intern, Anna, who recently received a Biology degree from the University of Puget Sound, and arrived at PPS in May.  Anna has always had a passion for animals, and is eager to learn how to care for New World primates.  She is a skilled writer, having spent time as the editor of her College’s science magazine.  We look forward to Anna contributing her writing skills to the PPS Manuals and Medical Records.  Her references describe Anna as curious, compassionate, and trustworthy, qualities that are ideal for an animal caregiver.  Anna has already proven to be a valuable asset to the PPS team, and we appreciate her enthusiasm to learn and commitment to the Sanctuary.  

Anna Writes:
…I’m thrilled to formally accept the position of resident intern! Thank you again for this opportunity. I can’t wait to make a positive contribution to the sanctuary and to work with everyone in the PPS family.

I’m excited to work with PPS because I am deeply concerned with having a positive impact upon the world. I’ve always been fascinated by animals, and I’ve really enjoyed diving into topics like animal consciousness and social cognition during my time at university. I’m looking forward to applying all of that book-knowledge while improving the lives of vulnerable animal populations.

During my internship, I want to gain mastery of animal care techniques and provide the best possible service to the monkeys. My goal is to learn to recognize each animal as an individual with a distinct history, personality, and needs. I would also love to take on a project involving public engagement— between the website, the blog, and social media, I imagine that there will be plenty of demand for content! I would be thrilled to help get people involved online with PPS.

HOW YOU CAN HELP the MONKEYS at PPS

Donated Produce for PPS
Common Ground Collective, another local non-profit, is now offering free harvesting services in upcountry Maui.  They will come to you to harvest the produce, and will then donate it to the non-profit of your choice.

The monkeys at Pacific Primate Sanctuary receive a wide variety of fresh fruits and vegetables in their daily diets.  Organic produce donations are greatly appreciated, so please coordinate with Common Ground Collective to contribute produce to PPS.

Contact Common Ground Collective, and let them know you would like to donate your surplus fruits and vegetables to Pacific Primate Sanctuary, using the following link: https://www.commongroundcollective.com/foster-farming

AmazonSmile
AmazonSmile is a simple and automatic way for you to support Pacific Primate Sanctuary every time you shop at Amazon, at no cost to you. When you shop at smile.amazon.com, you’ll find the exact same low prices, vast selection and convenient shopping experience as Amazon.com, with the added bonus that Amazon will donate a portion of the purchase price to PPS. Go to smile.amazon.com, and select Pacific Primate Sanctuary as your charity, or you can click on the following link:  https://smile.amazon.com/ch/99-0285731

GoodShop
GoodShop is THE go-to place to find all those coupon codes and promo codes on the web for thousands of stores from The Gap, Best Buy, Expedia, Target, Apple and more!  So, don’t miss a chance to save a bit of money, AND, when you shop through Goodshop, a percentage of what you spend is donated to Pacific Primate Sanctuary!

Give the Gift of Your Service and Volunteer Your Time
We are currently in need of more local Volunteers! We need Animal Caregivers, Handy People, and Gardeners/Landscapers. Retirees are welcome. If you live on Maui and are interested in joining the Pacific Primate Sanctuary’s Community, by volunteering your time and skills, please e-mail:  pacificprimatesanctuary@gmail.com

Facebook Fundraisers
Facebook now offers online fundraising opportunities, which allows anyone to create a fundraiser for Pacific Primate Sanctuary.  Many people have chosen to do a Birthday Fundraiser and raise funds for charity in honor of their birthday. On your personal Facebook page, click on the Fundraisers link, then select “Raise Money for a Nonprofit Organization”. You can then select Pacific Primate Sanctuary, Inc. as your charity, and begin raising donations by sharing with your friends and family.
https://www.facebook.com/fundraisers/about/

How to Contribute Directly
We rely on and deeply appreciate your continued partnership. Please make tax-deductible donations to the Sanctuary on our Website: www.pacificprimate.org and on Facebook, using PayPal, or by sending a check to:                                  

Pacific Primate Sanctuary
500-A Haloa Road
Haiku, HI 96708

“Malama ‘Ola the Monkeys” and help us provide food, medicine
and supplies for the monkeys at Pacific Primate Sanctuary
and contribute to the care of the Beings with whom we share the Earth!

CONTINUING EDUCATION

Intern Kaylee: Special Topic
Altruism in Callitrichids

Scientists have wondered for a long time: what causes humans to act altruistically? Altruism is defined as “behavior by an animal that is not beneficial to, or may be harmful to, itself, but that benefits others of its species”2.  Altruism is very rare in the animal kingdom, as it is not generally helpful to the survival of an individual. Like humans, marmosets and tamarins demonstrate this unique behavior, especially in regard to food sharing.

In a paper by Hauser, it is noted that cotton top tamarins tend to share food with unrelated tamarins, who reciprocate the gesture. It was initially believed that Callitrichids (marmosets and tamarins) behaved altruistically due to the nature of their family structure, in which the entire group helps care for the young. A research team, led by J.M. Burkart, performed an experiment to assess the altruistic nature of Callitrichids, along with many other primate species. The premise of their test was to see if an individual would give their food to another individual without receiving anything themselves. The results of the test showed that the eagerness to share food was not consistent among the different species, but that a pattern was evident. Marmosets and tamarins would provide the bits of food to others of their own kind quite frequently, similar to humans. The majority of the other primate species only sparingly provided fellow group members with treats.

This was surprising to researchers because as chimpanzees and capuchins are known to be quite cognitively advanced.  Before this research was released, it was commonly believed that primates’ altruistic nature “could be attributed to factors they would share with humans: advanced cognitive skills, large brains, high social tolerance, collective foraging or the presence of pair bonds or other strong social bonds” (“The evolutionary roots of human altruism,” 2014). It is now believed that the altruism in a species is related to the level of cooperation in rearing offspring, including how frequently individuals, other than the mother, help to care for infants (cooperative breeding/allomaternal care).

Having a large extended family group provides many teachers to help young Callitrichids learn how to interact with others, to forage, to determine which foods are good to eat.  Sharing food is an important part of this learning process, and older siblings and parents regularly allow youngsters to take food right from their hands.  In the 1980’s and 1990’s, many of the marmosets and tamarins at PPS were housed in family groups. They were able develop their cognitive abilities based on care given to them from the many helpers in this family group. Other individuals in our care, for example ex-pets, did not have the benefit of being raised with others of their own kind.  For these monkeys, it is much more difficult to learn typical social cues and vocalizations, and we have found that these individuals have a much harder time forming normal social groups or sharing their food with other callitrichids. On the other hand, individuals who were raised in functioning family groups tend to share food easily and also tend to more readily accept other callitrichids as partners.

Resources
1.    University of Zurich. "The evolutionary roots of human altruism." ScienceDaily. ScienceDaily, 27 August 2014. .
2.    "altruism." Merriam-Webster.com. Merriam-Webster, 2019. Web. 9 March 2019.
3.    Faulkes, G. Christopher, Arruda, M.F., and M.A.O. Monteiro da Cruz. “Genetic Structure Within and Among Populations of the Common Marmoset, Callithrix jacchus: Implications for Cooperative Breeding.” The Smallest Anthropoids, Springer Science Business Media, LLC, 2009, pp. 114.
4.    Hauser MD, Chen MK, Chen F, Chuang E (2003) Give unto others: genetically unrelated tamarins preferentially give food to those that altruistically give food back. Proc R Soc Lond B 270:2363—2370
5.    J. M. Burkart, O. Allon, F. Amici, C. Fichtel, C. Finkenwirth, A. Heschl, J. Huber, K. Isler, Z. K. Kosonen, E. Martins, E.J. Meulman, R. Richiger, K. Rueth, B. Spillmann, S. Wiesendanger, C. P. van Schaik. The evolutionary origin of human hyper-cooperation. Nature Communications, 2014; 5: 4747 DOI: 10.1038/ncomms5747







We hope you have enjoyed this issue of Pacific Primate Sanctuary’s E-Newsletter. Thank you for your support of our life-giving work. Because of compassionate people, the Sanctuary can continue to provide a place of peace and happiness for primates saved from research laboratories, animal dealers, and tourist attractions. Here they can heal, form social groups, and live free from exploitation.