Impact of Perception on Animal Conservation Efforts and Biodiversity
By Adyasha Padhi, Biochemistry and Molecular Biology and Sociocultural Anthropology ’25
Humanity has impacted our planet’s biodiversity in extensive ways, both deliberately and accidentally. According to the World Wildlife Fund, there has been an average of a 69% decline in worldwide biodiversity since 1970 [1]. However, some geographical areas and ecosystems are disproportionally affected. Biodiversity in the Caribbean and Latin America has dropped 94% and their freshwater populations are experiencing an 83% decrease in biodiversity [1]. The four most significant drivers of biodiversity loss are land use change (30%), overexploitation (20%), climate change (14%), and invasive species (11%), all of which are associated with human activity [2]. Overall, the impact of all biodiversity drivers is increasing and so is the rate of biodiversity decline.
One of the major ways that we attempt to repair the damage that we have done to our planet is through wildlife conservation efforts. However, examining conservation efforts reveals startling trends in which species receive focused protection, policy efforts, research, and funding. These inequities call into question the efficacy of many widespread conservation programs.
What is biodiversity and why is it important:
Biodiversity refers to the variety of life on Earth at all levels, from genetic diversity in a population to organism diversity within an ecosystem. This encompasses both the sum of total life forms across an area and the range of differences between those forms. While the biodiversity of some organisms is widely valued instinctively, some are not, such as microbiota, insects, and plants. Nevertheless, these undervalued organisms perform functions that are essential to maintaining stable ecosystems. Biodiversity supports healthy life on Earth– a lack of diversity at any level of life can lead to ecosystem collapse. This is because greater biodiversity in individuals, species, and ecosystems leads to greater ecosystem stability, and the populations within them are more likely to be able to withstand a range of disturbances, such as disease outbreaks and climate change.
Biodiversity is usually explored at three levels: genetic, species, and ecosystem. For the purposes of conservation, species diversity is most often the focus. While genetic and ecosystem diversity are both extremely important, species diversity can offer insight into the health of both of these while being more manageable in scope. If species diversity is low in an ecosystem, that has implications on both the genetic diversity of the species that make up that ecosystem and that ecosystem as a whole in relation to other ecosystems. One way to measure species biodiversity is with a biodiversity index. A simple biodiversity index is calculated by dividing species richness (the number of species in an area) by species evenness (the total number of individuals in the same area) [7].
By using metrics such as the biodiversity index, researchers have found that biodiversity has been decreasing at an unprecedented rate [3]. Furthermore, certain areas around the equator known as biodiversity hotspots are experiencing biodiversity loss at even higher rates than other areas [3]. Human activity is contributing to all of the major driving factors for biodiversity decline, such as climate change, the effects of which are accelerated by the continued loss of biodiversity in ecosystems worldwide, creating a cycle of damage and loss.
Conservation: Who gets chosen, and why?
One way to mitigate the negative impacts humans have had on the planet is through conservation efforts, or protecting species and their habitats to restore populations and ecosystems. Conservation efforts typically fall into one of two categories: preventing further destructive forces from acting on ecosystems, such as stopping deforestation or stimulating populations through breeding and protection, in order to revitalize injured populations. These efforts are typically in-situ (conservation of habitats, species, and ecosystems where they naturally occur) or ex-situ (conservation of elements of biodiversity out of the context of their natural habitats, such as zoos, seed banks, and botanical gardens).
Financial, land, and labor resources are limited, so the conservation of certain areas or species is forced to be prioritized over others. A common approach for selecting these priority areas for conservation is to focus on hotspots of diversity. These “hotspots” are regions of high conservation priority due to their high levels of richness in species, rates of endemism (uniqueness to that certain region), and threats to survival. Currently, there are 36 designated hotspots worldwide. These biogeographic regions are most commonly found around the equator and hotspots have lost around 85% of their habitat area [3].
Another metric used to determine the status of certain species is the International Union for Conservation of Nature (IUCN) Red List. The IUCN is an international organization for nature conservation and the sustainable use of natural resources. It is most well known for its Red List, which is regarded as the world’s most comprehensive inventory of the global conservation status of biological species. They report that they have assessed 42,100 species at risk of extinction, but a 2019 United Nations report estimates that of all existing species, a million are at risk of extinction in total. This disparity reflects how few existing species have been assessed by the IUCN. Prioritizing certain species and ecosystems is needed due to the limited resources that conservation organizations have, and the increasingly complex social, cultural, and political factors that further inhibit conservation efforts.
Conservation efforts are often focused on a single species, and these species are often categorized into three categories that define their relation to their ecosystem: keystone, indicator, or flagship, with overlap between the categories. Keystone species play an essential role in the structure, function, or productivity of a habitat or ecosystem and the disappearance or diminishment of one of these species may lead to significant ecosystem change and dysfunction. One famous example of a keystone species is the Grey wolf in Yellowstone. As predators that regulate prey populations, the wolves enabled many species of plants and animals to flourish. After their disappearance in 1926, their reintroduction into Yellowstone in 1995 was a conservation effort that had highly successful effects on the entire food structure that defines the Northern Rockies ecosystem [12]. An example of a keystone species acting as ecosystem engineers are beavers, who regulate tree growth in the river ecosystems and also divert rivers with their dams, creating wetlands and ponds which support a wide range of organisms, which would not be able to survive in the more aggressive environment of a river. Despite their small size, bees are also a keystone species due to their integral role in pollination [13]. Plants too can be keystone species, such as Mangrove trees, which play an essential role in many coastal ecosystems by protecting coastlines from the impacts of waves and reducing erosion, while also providing a safe haven for small marine organisms to survive, which in turn has wider impacts throughout the food web.
Indicator species are species or groups of species chosen as an indicator or proxy for the state of an ecosystem. An example of this is crayfish as indicators of freshwater quality and peregrine falcons as an indicator of pesticide loads. Flagship species are selected to act as a symbol for a defined habitat or environmental cause due to their “charismatic” nature, especially in Western cultures, which is often where the funding for many conservation campaigns comes from [5]. These flagship species are typically large mammals that may or may not be keystone species and are not necessarily good indicators of biological processes in their ecosystems or of the conversation status of their ecosystem. Examples include tigers, kangaroos, elephants, and pandas [11].
Flagship species campaigns centered around these “charismatic” animals have been found to be more effective than other types of conservation campaigns [4]. Researchers have found that public donors were more likely to donate to a flagship charismatic species, regardless of the endangered status of the species [4]. Features of charismatic species include colorful coats or forward-facing eyes [6] because these appeal most to the broadest audience and these species are often featured in media & spaces where the public can interact with them, such as in movies or in zoos. The Similar Principle Theory finds that humans have a preference for animal species that are more similar to them. This is in both physical characteristics, such as forward-facing eyes and expressive faces, and social characteristics. As such, some researchers posit that the chances of survival for many species depend as much on human preferences as on existing biotic and abiotic factors, if not more [4].
Paradoxically, many of the animals regarded as the most charismatic are at high risk of imminent extinction, which some researchers attribute to the biased perception of the abundance of these animals since they are commonly overrepresented in our culture, such as pandas, tigers, and lions being common in our zoos, media, and educational material [6]. While some have called out this focus on animal charisma as being too narrow and excluding many species, charismatic flagship species conservation campaigns have been more successful in securing funding than campaigns that do not feature a flagship species [4]. However the status of many other species which share their habitat – or are vulnerable to the same threats – may also be improved by campaigns that target charismatic species. This is due in part to the large habitats that charismatic animals tend to live in due to their size and their position often being higher up on the food chain. Ultimately, researchers are calling for the shift away from campaigns centered around charismatic species and towards ones that focus more on the health of the ecosystem as a whole, even if this is less visible [6].
Conclusion
Biodiversity on all levels is an essential aspect of global health as it supports ecosystem health and stability via pollination, water purification, climate regulation, seed dispersal, agricultural pest control, and nutrient cycling. As such, all organisms, biotic, and abiotic factors that make up an ecosystem are extremely important in their own ways, and this means that even organisms that we don’t intrinsically value or find charismatic are important. Protecting all species is integral to protecting the health of the world as a whole and combating climate change.
References
[1] “69% average decline in wildlife populations since 1970, says new WWF report,” World Wildlife Fund, 2022. https://www.worldwildlife.org/press-releases/69-average-decline-in-wildlife-populations-since-1970-says-new-wwf-report
[2] The Royal Society, “What is the human impact on biodiversity? | Royal Society,” royalsociety.org, 2022. https://royalsociety.org/topics-policy/projects/biodiversity/human-impact-on-biodiversity
[3]N. Myers, R. A. Mittermeier, C. G. Mittermeier, G. A. B. da Fonseca, and J. Kent, “Biodiversity hotspots for conservation priorities,” Nature, vol. 403, no. 6772, pp. 853–858, Feb. 2000, doi: https://doi.org/10.1038/35002501.
[4]A. Colléony, S. Clayton, D. Couvet, M. Saint Jalme, and A.-C. Prévot, “Human preferences for species conservation: Animal charisma trumps endangered status,” Biological Conservation, vol. 206, pp. 263–269, Feb. 2017, doi: https://doi.org/10.1016/j.biocon.2016.11.035.
[5]C. Mazzoldi et al., “From sea monsters to charismatic megafauna: Changes in perception and use of large marine animals,” PLOS ONE, vol. 14, no. 12, p. e0226810, Dec. 2019, doi: https://doi.org/10.1371/journal.pone.0226810.
[6]F. Courchamp, I. Jaric, C. Albert, Y. Meinard, W. J. Ripple, and G. Chapron, “The paradoxical extinction of the most charismatic animals,” PLOS Biology, vol. 16, no. 4, p. e2003997, Apr. 2018, doi: https://doi.org/10.1371/journal.pbio.2003997.
[7]“Guide on biodiversity measurement approaches (2nd edition),” Finance for Biodiversity Pledge. 2022. https://www.financeforbiodiversity.org/publications/guide-on-biodiversity-measurement-approaches/
[8]K. Whiting, “6 charts that show the state of biodiversity and nature loss – and how we can go nature positive,” World Economic Forum, Oct. 17, 2022. https://www.weforum.org/agenda/2022/10/nature-loss-biodiversity-wwf/
[9]J. H. Lawton and K. J. Gaston, “Indicator Species,” ScienceDirect, Jan. 01, 2001. https://reader.elsevier.com/reader/sd/pii/B9780123847195000745?token=68CA7F85D7A3FD42B151DC0DDD681D1E44822EC03A422ABFA252CF19E4E9E70F88BD7C79CB9E562C1AD10E92193926FA&originRegion=us-east-1&originCreation=20230411171712
[10]M. C. Horner-Devine, K. M. Carney, and B. J. M. Bohannan, “An ecological perspective on bacterial biodiversity,” Proceedings of the Royal Society of London. Series B: Biological Sciences, vol. 271, no. 1535, pp. 113–122, Jan. 2004, doi: https://doi.org/10.1098/rspb.2003.2549.
[11]J. Qian and H. Zhuang, “Selecting flagship species to solve a biodiversity conservation conundrum,” Plant Diversity, Jan. 2021, doi: https://doi.org/10.1016/j.pld.2021.01.004.
[12]A. P. Dobson, “Yellowstone Wolves and the Forces That Structure Natural Systems,” PLoS Biology, vol. 12, no. 12, p. e1002025, Dec. 2014, doi: https://doi.org/10.1371/journal.pbio.1002025.
[13]A. Easton-Calabria, K. C. Demary, and N. J. Oner, “Beyond Pollination: Honey Bees (Apis mellifera) as Zootherapy Keystone Species,” Frontiers in Ecology and Evolution, vol. 6, Feb. 2019, doi: https://doi.org/10.3389/fevo.2018.00161.
Greater glider populations are decreasing in Australia while selective logging regimes power on
By Adam Vera, Applied Chemistry ’23
The greater glider (Petauroides volans) in a hollow-bearing Eucalyptus tree
Australia’s eucalypt forests along the eastern coast were once abundant with the country’s iconic arboreal marsupial, the greater glider (Petauroides volans). Native to the Central Highlands of Queensland and New South Wales, it has long been recognized as the cute and clumsy acrobat of the treetops—it can glide over 100 meters! It can serve as an indicator of ecosystem health, as it is usually the first species to leave an area exposed to environmental harm, such as wildfire, disease, or anthropogenic disruption. This unique trait makes them an umbrella species: when they are protected, many other species are as well. The core habitats of the greater glider are the hollows that form in old-growth Eucalyptus trees. Hollow-bearing trees are essential because they serve as protection from predators and harsh weather, and they provide ready access to the eucalyptus buds and leaves that they eat. These marsupials of Australia have long embodied the land; sadly, like many other species around the world, they are facing endangerment and vulnerability due to anthropogenic (human activity) action. Their populations are already decreasing which suggests an increase in environmental harm and a decrease in non-use land value [1].
Bushfires have increased in both intensity and quantity in eastern Australia, most notably in 2020 [4]. Global temperature and humidity are factors that can increase rates of bushfires due to increased greenhouse gas emissions and the warming effect they have on the atmosphere [4]. Bushfires have resulted in the habitat destruction and forced migration of many species, including the greater glider, due to the reduction in hollow-bearing trees. Climate change has not been the only factor negatively impacting the glider; selective logging regimes have been steadily removing hollow-bearing trees ideal for the glider. Intensive logging and forest clearing in the site regions of the glider have targeted tall, straight, unburnt trees for harvest since the 1960s to accommodate early machinery [1]. Trees that are targets for loggings are often old-growth because they are well established and durable. Unfortunately, they are also frequently hollow-bearing and therefore habitats for the glider. Selective logging has not slowed down for the protection of this species, nor has it avoided known habitat areas. Without a change, the greater glider will become extinct. Increase in public support for a reduction of selective logging will raise awareness of the unjust treatment of native species and improve the lives of the gliders .
The extinction of the greater glider grows imminent as selective logging destroys habitats. The Department of Climate Change, Energy, the Environment and Water within the Australian government added the species to its endangered species list in July of 2022 [2]. A study performed by researchers at the University of Wollongong, Australia in 2018 proved a positive relationship between logging intensity (measured as acres of old growth forest logged) and glider abundance. They did so by cross-referencing forest sites that had been logged and the presence of the gliders within them, determined via in-person ground monitoring. The removal of 60 cubic meters of hollow-bearing trees (m3) per hectare (10,000 m3) cut the predicted abundance in half at a site within northern New South Wales [2].
“Predicted occurrence of the glider in the Central Highlands of Victoria with respect to the Number of Hollow-Bearing Trees”
In comparison, another team at the Australian National University discovered, using similar methods, the predicted occurrence of the glider in a site in the Central Highlands of Victoria had dropped roughly 30% from 2000 to 2015, as shown to the left [3]. This is consistent with a near 50% loss of hollow-bearing trees per site due to selective logging over the same time frame. The greater glider is an umbrella species because of its innate ability to indicate harmful changes in a local environment, as previously stated. With the loss of this species, many other wildlife species will not receive enough advanced warning about such harmful changes, leaving them vulnerable. Additionally, its predators may experience food shortages and have to relocate, disrupting local ecosystems and creating imbalance in food webs. Furthermore, the lack of management on logging means the decrease in trees is likely to continue, possibly resulting in the extinction of the greater glider.
Wildfires and selective logging regimes are reducing the number of suitable habitats per acre for the greater glider at an increasing rate, as shown in the figure above [2]. These two variables must be controlled in order to protect the species and reduce habitat disturbance. The team from the University of Wollongong suggested fire managers use prescribed fire to reduce the spread of unplanned wildfires. If used, they must be on only low to moderate fire condition days, as well as at a safe distance from known habitats of the gliders [2]. Another active management strategy suggested by both teams is the reduction of selective logging. While easier said than done, it is essential that logging managers not harvest in areas of high species population, as well as not overharvest old growth, hollow-bearing trees in a small, dense area [3]. In the meantime, artificial hollows can be used as temporary habitats [3]. By following these solutions, the species population in eastern Australia will begin to recover and have suitable, comfortable habitats.
“A greater glider at the Australian Conservation Foundation.”
The benefits of preserving this species include the protection of an iconic Australian marsupial, the protection of other species under its umbrella, and the upholding of the standard for how to treat endangered species. The greater glider still inhabits eastern Australia, and can once again live in robust populations with the support of government and concerned citizens.
References:
- McLean, C., Kavanagh, R., Penman, T., & Bradstock, R. 2018. The threatened status of the hollow-dependent arboreal marsupial, the Greater Glider (Petauroides volans), can be explained by impacts from wildfire and selective logging. Forest Ecology and Management, 415-416: 19-25. https://doi.org/10.1016/j.foreco.2018.01.048
- Threatened species list. EPBC Act List of Threatened Fauna. (n.d.). December 2, 2022, www.environment.gov.au/cgi-bin/sprat/public/publicthreatenedlist.pl#mammals_endange red
- Lindenmayer, Blanchard, W., Blair, D., McBurney, L., Taylor, C., Scheele, B. C., Westgate, M. J., Robinson, N., & Foster, C. 2021. The response of arboreal marsupials to long‐term changes in forest disturbance. Animal Conservation, 24(2): 246–258. https://doi.org/10.1111/acv.12634
- Dunne, Daisy. 2020. Explainer: How climate change is affecting wildfires around the world. Carbon Brief, n.p. https://www.carbonbrief.org/
The Impact of vasopressin and oxytocin and pair-bonding on social development in prairie voles (Microtus ochrogaster)
By Hera Choi, James Hagerty, Ananya Narasimhan, Elyza Ramirez, Rana Sherkat, Karen Bales, Logan Savidge, Academic Editors
Acknowledgement: We offer our sincerest appreciation to Dr. Karen Bales and Logan Savidge for their continued guidance and support throughout our writing process for this literature review. The edits and remarks provided on their behalf not only allowed us to polish up the paper, but also gave us many opportunities to learn more about the nature of the prairie voles we work with. We would also like to thank the editors of the Aggie Transcript for providing us excellent feedback, tools, and edits to bring us to our finished literature review.
Abstract:
Prairie voles are a monogamous rodent species that exert a variety of human-like social behaviors. Voles are often used as animal models to study certain behavioral patterns in humans. This paper attempts to review the neurobiology of prairie vole pair-bonding. Hormones such as oxytocin and vasopressin are known to have biological effects on prairie vole pair-bonding development. We hypothesize that the introduction of oxytocin and vasopressin may facilitate behaviors such as aggression since it has been revealed that pair-bonding highly impacts social behavioral displays.
Introduction:
Microtus ochrogaster, commonly known as the prairie vole, exhibits many similar behavioral patterns to humans, including biparental care, alloparenting (the presence of non-breeding male and female voles participating in pup care), pair-bonding, and social attachment. As such, prairie voles have been used widely in studies investigating various mental health disorders, namely autism spectrum disorder, depression, addiction, and schizophrenia, providing researchers with more information on human behaviors related to cognition, parenting, and interpersonal relationships [1]. This review aims to demonstrate that pair-bond formation, in conjunction with the hormones oxytocin and vasopressin, aids prairie vole social development. Although these conclusions can be made with current research, further research should can address limitations such as including more female prairie voles in these studies and comparing oxytocin uptake between both sexes.
Prairie voles live in communal groups, typically consisting of males and females with their offspring [2]. Pair-bonding between male and female prairie voles can facilitate the biparental care of their offspring as opposed to monoparental care. As a biparental species, both male and female prairie voles divide postpartum parental activities relatively equally. Both maintain and build their nest, cache food, lick, groom, and brood pups [4]. The only parental activity strictly maternal is the nursing of pups [4]. Biparental care is not the only form of parenting that vole pups can receive. Parenting styles can also vary in duration of contact and the presence of alloparental care. Extended family lines often exist, in which juveniles remain in the natal nest as alloparents [5].
Once a male and female pair form an established pair-bond, they remain socially monogamous. A standard method of measuring a pair-bond in animals in the lab is partner preference testing, or measuring the mate’s preference for their partner over a stranger of the opposite sex. Through partner preference testing, researchers have demonstrated that injecting high doses of oxytocin (OT) or vasopressin (AVP) is associated with the development of a pair-bond in both male and female prairie voles [6]. Antagonists of OT or AVP receptors interfere with pair-bond formation, further supporting that both OT and AVP are necessary for pair-bonding behaviors [5]. AVP also regulates nonresident males’ exclusion by the resident male, also known as mate-guarding, further maintaining the pair-bond between the resident male and female vole [2].
Social monogamy is a characteristic that is rarely seen in the animal kingdom. Critical hormones combined with prairie voles’ social environment make these coinciding behaviors possible.
The Role of Hormones in Affiliative Behaviors
Although hormones do not directly cause behavioral changes by influencing the three behavioral components (sensory systems, central nervous systems, and effectors), hormones can increase the possibility that appropriate responses will be expressed in response to certain stimuli [6]. Studies have aimed to reveal mechanisms in which hormones act on pair-bonding behavior. Receptor autoradiographic binding procedures, in which radioactive molecules are attached to ligands to visualize receptor distributions, showed higher vasopressin receptor (V1aR) densities in the medial preoptic area of the brain in pair-bonded male prairie voles compared to that of sexually naïve male voles [7]. It has been supported that the V1aR is necessary for both the formation and maintenance of pair-bonds in prairie voles, suggesting AVP has a significant role in pair-bonding behavior, particularly once male prairie voles reach sexual maturity [8].
However, in female prairie voles, AVP inhibition appears to have little effect on altering pair-bonding behaviors. Instead, the use of oxytocin receptor antagonist, ornithine vasotocin (OTA), results in inhibition of partner preference formation [8]. It has been demonstrated that the administration of OT with dopamine (DA) can induce partner preference without mating in female prairie voles [8,9]. Some studies have expanded on the role of OT and DA in pair-bond formation, revealing that the presence of OT and DA D2-type receptors in the nucleus accumbens (NAcc), the mediator of motivation and action, are both vital in pair-bond formation in female voles [10]. This is further supported by findings that have determined a positive correlation between affiliative behavior and oxytocin receptor density within the NAcc [11,12]. High concentrations of both OT and DA D2-type receptors within the NAcc suggest that affiliative behaviors and pair-bonding are extremely rewarding for female prairie voles.
While the effects of AVP and OT inhibition on vole pair-bonding behavior are well studied, there have also been studies that have looked at the direct impact of administration of these hormones. Through partner preference testing, researchers have demonstrated that injecting high doses of AVP or OT is associated with the development of a pair-bond in both male and female prairie voles [13]. However, it has been shown that AVP administration to juvenile male voles can later result in impediments in partner preference formation [14]. Similar to what was observed in adult female voles, treatment of OT during the neonatal stage significantly decreases the display of partner preference-related behaviors in female voles [15]. These findings demonstrate possible dual effects of a single hormone determined by the dose, age, and duration of administration.
The Role of Hormones in Social Aggression
Social recognition is an integral component of prairie vole behavior, permitting this species to distinguish one conspecific from another for protection, inbreeding avoidance, monogamous mate selection, and comfort [16]. Aggression or affiliation displays are based on the lack or presence of recognition, respectively, likely mediated by oxytocin receptors (OXTR) [16]. Prairie voles commonly show aggression towards non-familiar individuals, especially after forming a pair-bond with another vole [6]. In many species of mammals, gonadal hormones have a prominent role in mate guarding and mating-related aggression [6]. However, it has been supported in prairie voles that the removal of gonads has little effect in decreasing aggression [17,18]. Instead, AVP and OT, rather than gonadal hormones, appear to control aggressive behaviors in prairie voles. For example, injection of AVP in adult male prairie voles increases intermale aggression. Meanwhile, developmental exposures of AVP can induce post-mating-like aggressive behaviors in sexually naïve males [19]. Sexually dimorphic roles are also present in aggression behaviors, with AVP administration having less effects on aggression in female voles. AVP receptor antagonists do block female aggression, highlighting the need for AVP receptors in aggression behaviors, even in female voles [19].
Aggression in female voles and its mechanisms have not been studied as extensively as it is in males. There are indications that OT may play a significant role in female vole aggressive behaviors. Females treated with OT following weaning show increased intrasexual aggression, while males treated with the same procedures are not affected [20]. Developmental OT treatment also results in decreased social behaviors in female voles [20]. Overall, further investigation on the effects of OT on male prairie vole guarding and aggression as opposed to female prairie voles is needed to make comparative conclusions.
Vole Behavior and Hormones
This review looked in depth at prairie vole behaviors related to the hormones AVP and OT. Together, both hormones induce social behaviors in male and female prairie voles, particularly those related with affiliation and pair-bonding. It is important to note that hormonal treatment may result in very different effects based on the developmental stage of the voles, the dosage of hormones, and the surrounding environment. This may be particularly important when experimenting with voles across multiple developmental stages, but this has yet to be studied. Further research should investigate whether AVP and OT have differential effects on prairie vole development, as hormonal influences tend to change over time.
Sexual Dimorphism
In all behavioral aspects, including aggression and pair-bonding, sexual dimorphism was observed in response to specific hormone inhibitors and hormone treatments. AVP has been found to be more important for adult male prairie vole pair-bonding, whereas OT and DA are necessary for pair-bonding in adult female voles. However, the effects of AVP and OT become more complex depending on when additional injections have been administered during the prairie vole’s life. Although AVP is significant for male prairie vole pair-bonding, administration during the juvenile stage can actually impair the formation of partner preferences. This effect is also seen in neonatal females, but with OT and not AVP. The difference in hormonal physiology may be a factor in the sexually dimorphic behaviors we see in the two sexes, though more research is needed for conclusive remarks. It may also suggest that the neurobiology between males and females is different from one another, at least in the aspect of pair-bonding.
A general trend that was discovered was that there had been more research done regarding male prairie voles. Due to the fact that the two sexes of voles show dimorphic behaviors, it is important to study both sexes of voles separately to prevent generalization of prairie vole neurobiology.
Prairie voles have become valuable organisms through which we can observe many aspects of human behavior. Although prairie vole neurobiology is incredibly complex, it paves the way for more research to be done to clarify the link between hormonal activity and behavior for both prairie voles and humans alike. Further routes of research that we suggest are quantifying the relationship between AVP receptors and aggression in female voles, since current studies mostly address this relationship in males. Similarly, we can address the effect of OT on intrasexual aggression in male prairie voles to comparatively study the effects of OT between sexes. Research of these factors may also be enhanced by including trials on prairie voles of different developmental stages to study the long-term outcomes of these hormones on behavior. Overall, our hypothesis linking OT and AVP to the neurobiology of pair-bonding and subsequent behaviors is supported by the literature, but there are many gaps to fill regarding the comprehensive impact of these hormones and pair-bonding on social displays and behavior between both sexes and across developmental stages.
References:
- McGraw, L., & Young, L. 2010. The prairie vole: an emerging model organism for understanding the social brain. Trends In Neurosciences. 33(2): 103-109. Doi: =10.1016/j.tins.2009.11.006
- Carter, C. S., & Getz, L. L. 1993. Monogamy and the Prairie Vole. Scientific American. 268(6):100–106.
- Thomas, J. A., & Birney, E. C. 1979. Parental Care and Mating System of the Prairie Vole, Microtus ochrogaster. Behavioral Ecology and Sociobiology. 5(2): 171–186.
- Roberts, R., Zullo, A., & Carter, C. 1997. Sexual Differentiation in Prairie Voles: The Effects of Corticosterone and Testosterone. Physiology & Behavior. 62(6): 1379-1383. doi: 10.1016/s0031-9384(97)00365-x
- Cho, M. M., De Vries, A. C., Williams, J. R., & Carter. C. S. 1999. The Effects of Oxytocin and Vasopressin on Partner Preferences in Male and Female Prairie Voles (Microtusochrogaster). Behavioral Neuroscience. 113(5): 1071-1079. doi:10.1037//0735-7044.113.5.1071
- Nelson, R. J., & Kriegsfeld. L. J. 2018. An Introduction to Behavioral Endocrinology (5th ed). Massachusetts : Siauner.
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- Insel, T. R., & Hulihan, T. J. 1995. A Gender-Specific Mechanism for Pair Bonding: Oxytocin and Partner Preference Formation in Monogamous Voles. Behavioral Neuroscience,\. 109(4): 782-789.
- Williams, J. R., Catania, K. C., & Carter, S. 1992. Development of Partner Preferences in Female Prairie Voles (Microtus ochrogaster): The Role of Social and Sexual Experience. Hormones and Behavior. 26: 339-349.
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- Olazábal, D. E., & Young, L. J. (2006a). Oxytocin receptors in the nucleus accumbens Facilitate “spontaneous” maternal behavior in adult female prairie voles. Neuroscience, 141(2), 559–568. https://doi.org/10.1016/j.neuroscience.2006.04.017
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Why Your Dog is Itchy: A Review of Common Skin Allergies
By Jeffrey Nguyen, Animal Biology, ‘19
Author’s Note: I originally wrote this piece for UWP 104E: Writing in the Sciences. The assignment called for an explanation of any scientific topic to the general public and I thought to write on a topic that would be both useful and relatable to pet owners. Skin allergies affect dogs of all breeds and can bear severe consequences if left untreated. I hope that this paper increases awareness on animal health and convinces pet owners to consider taking a second glance in those moments they observe something out of the ordinary.