Motion Tracking System
Subject: Science (Department of Math, Physics and Computer Science)
Presenters: Prashant Timalsina, Jeremy Castagno, Jeff Gagnon
Faculty Sponsor:
Dr. Jeremy Castagno
Basic concepts in kinematics are often explored in a physics laboratory setting by measuring the position of a cart on a linear air track. Traditionally this is done by attaching multiple “flags” of known length to the carts and measuring the time it takes the flag to pass through a photogate. However, to acquire enough data to plot the position or velocity of the cart as a function of time requires multiple trials and careful reproduction of the initial conditions. This process is often confusing, difficult for students to understand, and fraught with error. A better approach would be to measure the position of the cart directly as a function of time in a single trial.
We propose a novel low cost hardware and open-source software solution to this problem that utilizes computer vision techniques. Our motion tracker system consists of a webcam (with tripod or other mounting platform), a raspberry pi microcontroller, a calibration poster board representing the reference frame, and a cart with a colored trackable sticker attached to it. The software interface is web-based and is controlled through either a laptop or a smartphone. The software allows students to initialize and calibrate the system, collect the position and time data, filter the data, plot various graphs, and save the raw and processed data for further analysis.
The validity and reliability of our position measurements were determined by comparing the results from our motion tracker system to those obtained by a Qualisys optical motion capture system (which is the industry gold standard method of determining the location of an object in space). Overall, our system was shown to be both reliable and valid, easy to use by students, and conceptually a better method for collecting data to understand kinematics.
Drosophila melanogaster Gene CG31414: The Search to Connect the Structure and Function of the Gene to its Human Ortholog
Subject: Science (Biology)
Presenters: Damian Gilrein & Alek Turi
Faculty Sponsor:
Chris Abdullah
The gene highlighted in this research, CG31414, present in fruit flies (Drosophila melanogaster), has not previously been researched extensively despite potential relation to human (Homo sapiens) health. Our objective was to further understand the fly gene by determining its function and subsequent gene product, as well as similarities and differences between the fruit fly gene and its human ortholog. The next goal was to determine the implications of the role this gene plays in human health and demonstrate the use of model organisms to further understand the human genome. The CG31414 gene in Drosophila melanogaster encodes an enzyme called Glucocerebrosidase 1b (GBA1b). To gather further data on the CG31414 gene, information about the type of gene product, the biochemical reactions it catalyzes, the effects of mutations, and more, were necessary to understand the function of the gene. Internet resources, such as NCBI blast, Tcoffee, Primer 3, etc., were used to analyze the genetic, mRNA and protein sequences against their human orthologs, demonstrating a connection between the structure and function of these genes. The results lead us to conclude that there are two versions of the GBA1 gene (GBA1a & GBA1b) in Drosophila melanogaster, however only one version exists in Homo sapiens. The GBA1 gene is closely related to a sequence present in the human genome, therefore implying the sequences are orthologs. Recent studies have linked mutations in the GBA1 gene to neurological diseases, such as Gaucher disease, Parkinson’s and Lewy body dementia. Therefore, further research into the GBA1 gene may contribute to a deeper scientific understanding of these neurodegenerative diseases and their mechanisms. This research implies that there is more to be understood about the role this particular protein plays in many human neurological disorders and further research can be done based on the results obtained in this study.
Drosophila Melanogaster CG31148 Gene displays Homology to Human GBA
Subject: Science (Sports Biology)
Presenters: Madelyn Vianney & Hayleigh Rosa
Faculty Sponsor:
Chris Abdullah
This study investigated and compared genes (CG31148) between humans and the fly species Drosophila melanogaster, a common fruit fly. Fruit flies have many similarities to us, sharing around 60 percent of our genes with them. They are very useful tools when studying diseases and treatments. However, there is still much research needed to be done between humans and flies. Here, we present a mutation that is present in humans which causes diseases such as Gauchers, Parkinsons, and in some cases, Lewy body disease. This gene is called GBA1a in flies and it is orthologous to the GBA mutation in humans. This mutation causes a buildup of glucoceramide in the lysosome in the cells and can affect more than one type of cell. This can lead to many lysosomal storage diseases. We found this out by using multiple different types of resources, such as fly base and NCBI websites. We then looked at the DNA and RNA sequences, as well as the protein sequences of the flies and compared each to the human ortholog with the DNA showing a 100% similarity but a small query coverage, and the mRNA showing a 79.69% and determined the introns and exons from the sequences using the splign website. After getting this information we then designed primers to amplify DNA in the sequence of the flies to further research the mutation that is carried among these flies. Our results have shown that the DNA and RNA sequence are very similar to each other, as well as the protein sequences showing a shared homolog and indicating an evolutionary history between these two genes. This research is very important in finding out what can cause and how to treat GBA associated diseases, with a more ethical approach.
Linking Drosophila melanogaster gene CG 33090 with homologs that suggests spastic paraplegia
Subject: Science (Sports Biology)
Presenters: Megan Glanton & Morgan Barnes
Faculty Sponsor:
Chris Abdullah
Spastic Paraplegia is a human disease caused by a gene mutation in β-glucosidase-2 (GBA-2), it can be studied using Drosophila melanogaster or more commonly known as a fruit fly, was studied to see the effects of a mutation in the CG33090 gene, which is a homolog for the human gene. The gene studied codes for a digestive enzyme that converts a storage lipid into a sugar and a lipid. When the mutation is present the pathway is altered and the storage lipids can not be digested. The research methods within this experiment included, finding the DNA, RNA, and protein sequences of the gene within both the fruit fly and the human ortholog. Once this was found we were able to complete comparative alignments with the two sequences side by side and determine the relevance to each other. By comparing the sequences it was found that both were greatly similar to each other. The findings of these testing showed that these fruit flies can be used for testing instead of performing tests on humans when determining how to go about Spactic Paraplegia testing and possible cures for humans in the future. This is because the findings between the fruit fly and the humans show that they both have the same gene and it causes similar results in both.
D.melanogaster Gene CG33090 Shows Similitude to Human Gene GBA2
Subject: Science (Biology)
Presenters: Alex Candelaria & Brayan Mendez
Faculty Sponsor:
Chris Abdullah
Drosophila melanogaster, more commonly known as the fruit fly, is used by researchers to understand genetic diseases in humans. Two-thirds of all human disease-causing genes are also present in fruit flies. The CG33090 gene was the subject of this study. Initial information was acquired utilizing the NCBI databases even though this gene has yet to be described. The DNA of the gene was compared to the human genome using the NCBI blast program. Upon discovery, Glucosylceramidease Beta 2 (GBA 2), an enzyme, covered 74.45% of human genes mRNA. The functionality of this enzyme included the degradation of glucosylceramide into free glucose and ceramide. Mutations in these functions lead to lipid homeostasis imbalances because of glucosylceramide's buildup. This mutation has been found to be the cause of hereditary spastic paraplegia (HSP), or more specifically, SPG46, which is described as a collection of neurological disorders that affect the lower limbs by producing stiffness and weakening over time.
D. melanogaster gene CG3376 as alternative to human homolog SMPD-1
Subject: Science (Sports Biology)
Presenters: Lise-Anne Orlich & Stefan Minyayluk
Faculty Sponsor:
Chris Abdullah
Analyzing and working with human cells can prove difficult due to ethical reasons and the long amount of time it takes to obtain a decent quantity of cells. Drosophila melanogaster, fruit fly, genome shares ~75% of the genes that cause diseases in humans. If it is possible to find a comparable gene in fruit flies that is responsible for a human disease, future research could work on the fruit fly gene in a cheaper and more efficient fashion. This may uncover more about the pathologies of the corresponding human diseases. Specifically, we were examining the feasibility of utilizing the fruit fly to study Niemann-Pick disease. Niemann-Pick disease is a metabolic disorder in which abnormal amounts of sphingolipids, a fat cell that plays critical roles in the formation of the lipid bilayer in cells, build up in various cells in the body. This results in a variety of detrimental symptoms, including death. In order to study Niemann-Pick, we aligned the fruit fly gene we were targeting, CG3376, with its human ortholog and compared their similarities. Once the similarity was confirmed, we amplified the CG3376 gene to improve the rate at which the target gene can be studied independently. In the end, we found that the Drosophila melanogaster CG3376 gene was similar to the human gene. This is useful as a fruit fly’s life cycle is much more rapid, and it is possible to breed many generations of fruit flies in a concentrated amount of time, increasing the rate at which the disease and its pathologies can be studied. The implications of this demonstrate the possibility of utilizing the fruit fly genome to study its human ortholog, with the intention of finding possible treatments.
nSMase Encodes for Catabolic Enzyme in Sphingolipid Metabolism in Drosophila
Subject: Science (Environmental Science)
Presenters: Jacob Callaghan & Adam Sowinski
Faculty Sponsor:
Chris Abdullah
Neutral sphingomyelinase (nSMase) is a gene that codes for the enzyme, sphingomyelinase. The function of sphingomyelinase is the breakdown of the molecular compound sphingomyelin into ceramide and phosphocholine. nSMase is an uncharacterized gene in Drosophila. There is limited research done on the nSMase, apart from its structure and predictions of its cellular functions. Throughout this semester, we analyze the DNA, RNA, and protein sequences of Drosophila, as well as metabolic pathways associated with nSMase. Using research techniques such as PCR testing and analysis, fly monitoring, and comparing DNA, RNA, and protein alignments on NCBI websites, we were able to further understand the functionality and the structure of nSMase, as well as how it relates to its human ortholog, SMPD2, commonly known as sphingomyelin phosphodiesterase, which shares a common function with nSMase in terms of ceramide signaling for cellular activities. We were able to relate nSMase to the sphingolipid metabolic pathway, as it’s one of the first enzymes involved in the multi-enzymatic metabolic pathway, including other enzymes like GBA2 and SMPD1. This metabolic pathway consists of many transduction routes, which are responsible for many cellular functions such as cell survival/proliferation, apoptosis, secretion, etc. Neutral sphingomyelinase is responsible for the breakdown of sphingomyelin into phosphocholine and ceramide, and this reaction occurs right outside of the golgi apparatus. Moreover, we observed that there’s 100% percent identity between both RNA sequences, and for the protein sequences, there’s a 65% query cover with a 34.98% percent identity (SMPD2 being the query). Neutral sphingomyelinase plays a significant role in many cellular activities, including apoptosis, secretion, and cell membrane maintenance. Surprisingly, mutations in our gene do not have any abnormalities regarding the sphingolipid metabolic pathway, and the reason for this is unknown.
Mutations in Drosophila melanogaster gene CG33090 and Homo sapiens GBA2 cause ataxia disorders
Subject: Science (Biology/Chemistry)
Presenters: David Handron
Faculty Sponsor:
Christopher Abdullah
CG33090 is an uncharacterized gene in D. melanogaster. Performing a comparative sequence alignment of the CG33090 amino acid sequence to the entire human genome predicts that CG33090 is homologous to GBA2 in H. sapiens. Compared to D. melanogaster the GBA2 protein is 62% similar to the human protein. GBA2 catalyzes the hydrolysis reaction that cleaves glucosylceramide into glucose and ceramide however similar to its paralog GBA1, GBA2 functions in the cytoplasmic side of the cell membrane while GBA1 functions in the lysosome of the cell membrane. DNA coding for green fluorescent protein (GFP) located on a plasmid is integrated into CG33090. This creates an additional region of the protein that can be visualized once the DNA is transcripted and translated to a protein. Imaging shows GFP highlighting the neuronal cell membranes, the same place that GBA2 is found in humans. Both point mutations and truncations found in human patients lead to the production of a protein that is unable to convert glucosylceramide to glucose and ceramide. A non-functional GBA2 protein leads to an accumulation of glucosylceramide in the cell, as it is never converted to glucose and ceramide. Without this recycling step, glucosylceramide accumulates. Mutations in M. musculus protein found in the same pathway as GBA2 also lead to an accumulation of membrane lipid precursors and show cerebellar atrophy This cerebellar atrophy is also seen in human patients. In D. rerio the mutation of GBA2 leads to abnormal neuronal outgrowth at the larval stage. D. melanogaster with CG33090 mutations are expected to show a deficit in their ability to crawl compared to wild-type subjects. Crawling assays with D. melanogaster larvae will be used to measure the impact of various genotypes for different CG33090 mutated flies. Flies with Wild type CG33090, a second chromosome deficiency, and an insertion in CG33090 will be crossed to create different genotypes and the crawling phenotype will be measured. We hypothesize that flies with mutations on both copies of the second chromosome will have a more severe impairment of their crawling ability. Currently, there are no known GBA2-specific drugs, and if GBA2 mutations in humans are modeled in flies there will be a model organism to cheaply and effectively screen for potential drug efficacy and specificity.
Diurnal Vocal Patterns of the Black Howler Monkey (Alouatta Pigra) at La Selva Biological Research Station, Costa Rica
Subject: Science (
Biology)
Presenters: Jade Kiang
Faculty Sponsor:
Melinda Fowler, Justin Compton
Black howler monkeys (Alouatta pigra) exhibit a number of distinguishable vocalizations, and the frequency of these vocalizations has been suspected to vary based on time of day but there are limited studies on the A. pigra vocal patterns. Primates use vocalizations as an important communication pathway. Howler monkeys in particular are known for their distinct vocalizations, but there is some uncertainty behind what drives some of their vocalizations, such as if they are territorial. At La Selva Biological Station in Sarapiqui, Costa Rica, an observational research study was conducted to investigate the diurnal vocal patterns of A. pigra. Data was collected in the early morning, late morning and afternoon. There were two sites on pre-existing forest trails and the number of vocalizations were recorded. The number of vocalizations were recorded for each observational period of 45 minutes and broken down into howls/roars, roar accompaniment, incipient roars, barks, and eh/whimpers. For each type of vocalization looked at in this study, there is a significant difference in the number of vocalizations for early morning when compared to the afternoon. There are no significant differences in vocalizations between late morning and afternoon sampling periods. As for late morning data in comparison to the afternoon, there is no significant difference and the null hypothesis can be sustained. An understanding of the vocalizations and their differences depending on time of day allows for one to better understand the behavior of A. pigra and develop further hypotheses regarding the use of types of vocalizations.
Soil PH Changes in Response to Distance From the Sarapiqui River in Central Costa Rica
Subject: Science (
Biology)
Presenters: Jane O'Brien
Faculty Sponsor:
Melinda Fowler, Justin Compton
The PH of soil is important because it can impact soil health within ecosystems. Soil Nitrogen is an important nutrient because its levels are determined by the levels of PH and it can facilitate proper growth within plants. Tropical rainforests often have low nitrogen levels due to PH. The variability of soil PH has been highlighted in past and recent studies . My motivation was to see if the influence of the Sarapiqui River altered soil PH and soil nitrogen levels because there is a scientific gap between the distance that a major water source has on PH and Nitrogen levels within soil. I sampled three sites near, middle, and far from the Sarapiqui River. Within each site, there were two plots and I collected 4 samples each at each site to test for PH, nitrogen, internal soil temp, moisture levels, and sunlight levels. I examined the levels of PH at each site, the effect of PH levels on nitrogen levels, if PH levels are correlated to distance, and soil temperature correlation to PH levels. The results of the study did not show a significant correlation between PH and Nitrogen levels for sites near, middle, and far from the river. However, there was some variability between mean PH levels and the distance from the Sarapiqui with the highest PH average level found at the near site. These findings matter because PH is very variable and identifying environmental variables helps predict optimal conditions for forest growth potential, and measures should be taken to ensure the ecology of certain areas have optimal conditions to thrive and contribute to the health of other factors within an ecosystem.
Flock Size and Habitat Preferability in Costa Rican Bird Species
Subject: Science (
Biology)
Presenters: Allison Olsen
Faculty Sponsor:
Melinda Fowler, Justin Compton
Costa Rica is home to a significantly high abundance of animals, specifically birds. Birds spend their time in a number of different types of habitats; some factors that contribute to their choice include resource availability and protection. Additionally, birds travel in flocks for a variety of reasons such as protection and reliability. This study examines Costa Rican birds, comparing flock size and species diversity in different habitats. It was performed at La Selva Biological Station, Puerto Viejo de Sarapiqui, Costa Rica. Birds were observed in a marsh as well as near a river for an hour per day for eight days in January 2023. Variables that were noted included flock size as well as species type. A t-test was used to compare the total abundance of birds observed at each site, and we also compared the mean flock sizes in each site using a t-test. Neither abundance nor flock size were significantly different between the marsh and the river. Lastly Shannon’s Diversity Index was used to find species diversity between the marsh and the river. The river site was shown to have more diversity than the marsh over the course of the observations. Overall, although Costa Rica provides great abundance of bird species’ more research should be done on flock sizes, habitat preferability, and species abundance, as this study found no significant results. Future studies may consider extending the time period to find significance.
A Study of Species Abundance and Diversity in a Tropical Rainforest using Camera Traps
Subject: Science (
Biology)
Presenters: Finn Katz-Cronin & Blane Hart
Faculty Sponsor:
Melinda Fowler, Justin Compton
Old-growth and succession forests are often compared in the field of conservation and management. Old-growth refers to a forest that has been developing for a long period of time, whereas successional plots are younger forests that have gone through different forms of disturbance and are going through a period of regrowth. Despite extensive research on plant species diversity within areas of secondary succession compared to old-growth, there are limited findings on animal species diversity and abundance in successional forests. This study was conducted in a tropical rainforest ecosystem in the Sarapiqui province of Costa Rica and aims to look at the difference in animal species diversity and species abundance in an area of early secondary succession compared to old growth forest. Non-random sampling was used, with cameras being placed on hiking paths and at sites where there was evidence of animal activity. The cameras were in place and collecting data for seven full days. Preliminary findings suggest that new, successional growth hosts a greater diversity of species than old-growth, with 13 individual species being identified in the successional growth forest compared to six species in the old growth forest. A similar trend was observed with the difference in abundance of species within the two zones. The differences between species detection rate in these study sites could be attributed to a few factors, including the Intermediate Disturbance Hypothesis, differences in site characteristics, such as access to water and the density of vegetation in the old-growth, and the quality of camera trap setup and placement. Since our study only took place over seven days, there may not have been enough time to gather representative data. This research highlights that camera traps provide valuable biodiversity and abundance data which can be used in the fields of conservation and management.
Aposematic pattern variation in a mainland population of the strawberry poison frog, Oophaga pumilio
Subject: Science (
Biology/Chemistry)
Presenters: Simon Hauser
Faculty Sponsor:
Melinda Fowler, Justin Compton
Aposematic coloration and patterning typically serve as a warning to predators in a variety of animals and it is exhibited by poison frogs (Dendrobatidae): a particularly brightly and intricately patterned group of organisms. In Oophaga pumilio, also known as strawberry poison frogs or the blue jeans frog, aposematic coloration serves as both a predator-deterrent and a mechanism in female sexual selection. Aside from the possibility that pattern spots can form and disappear over the course of a lifespan and injury, the individual variation of aposematic patterning within Oophaga pumilio populations has gone relatively unstudied. In this study I captured and photographed 19 unique individuals from a mainland population of Oophaga pumilio at La Selva Research Station. Using the computer software ImageJ, I marked and measured the dorsal patterning and dorsal surface area of 15 adults and 4 juveniles to compare body size and patterning. There was no significant correlation between: pattern coverage and dorsal surface area, mean spot size and dorsal surface area, or number of distinct spots and dorsal surface area. However, the mean spot size in adults decreases as the number of distinct spots increases for an individual. Essentially, with more dorsal surface availability, there should be more distinct spots, though having more distinct spots generally decreases the average spot size. Spots must be smaller to not overlap each other which results in the same dorsal pattern percent cover. In combination with the influence of injury on pattern, this study provides additional data which can be incorporated when using patterning for long-term recapture identification.
Simulating Self-Replication on a Turing Machine
Subject: Science (Computer and Information Science)
Presenters: Anmol Baruwal
Faculty Sponsor:
Tyler Markkanen
Simulating Self-Replication on a Turing Machine is a research topic that explores the properties and capabilities of Turing machines in the context of self-replicating programs. A Turing machine is a mathematical model of computation that consists of a tape divided into cells, a head that can read and write symbols on the tape, and a set of rules that determine the machine's behavior. Self-replication, on the other hand, refers to the ability of a program to generate an exact copy of itself as output.
In this research, we investigate how self-replication can be simulated on a Turing machine by defining a set of rules that enable the machine to read, write, and move on the tape in a way that generates a copy of its own source code. We used Python as a programming language to find the possibility of making a self-replication program. We explored various parts of self-replication, including using loops, conditional statements, and recursion, and we evaluate the efficiency and effectiveness of each approach.
The findings of this research have implications for the design and development of programming languages and the study of computational complexity, as well as for the fields of cryptography and security, where self-replication is an important consideration in the design of malicious software. Furthermore, Turing machine could also have implications for the field of biology, where it could be used to model and simulate biological systems, aiding in the development of new drugs and therapies, and advancing our understanding of complex biological processes like gene mutation and so on.
Territorial Habit Analysis of the Oophaga pumilio Poison Dart Frog
Subject: Science (Pre-PA/Health Science. Department of Biology/Chemistry)
Presenters: Ashley Pugliese
Faculty Sponsor:
Melinda Fowler, Justin Compton
The Oophaga pumilio poison dart frog is native to the Caribbean rainforests in Central America and tends to live in clusters. The primary function of territoriality in strawberry poison dart frogs is associated with reproduction. In male frogs, they will perch on their calling sites to deter male competitor calls, and then attract females. At the La Selva Biological Station in Costa Rica, humans would play a large role in the environmental discrepancies for Oophaga pumilio poison dart frogs. In this study, I primarily looked at their clusters in relation to human activity, because there may have been anthropogenic disturbances in these territories. Human trails would create a variety of different leaf litter levels that would contribute to the resources available for Oophaga pumilio poison dart frogs. I tested the hypothesis that there would be more frogs near human activity. I tested 2 plots, each with three 10-meter sections. The first plot was close to human activity (around 50 meters), whereas the second one was further away (around 1600 meters), and deeper in the forest. I recorded frog abundance each morning at dawn and after breakfast. Each sampling period was 10 minutes, and at these plots, I would also record weather conditions and leaf litter climate(dry or wet). I found that there was a significant difference in the abundance of frogs at the plot closest to human activity as opposed to further away. On average, there were 10 times more frogs in the ‘near human’ plot compared to the ‘far human’ plot. My observational research suggests that where there is more human interaction with the environment and leaf litter, there are a greater number of Oophaga pumilio poison dart frogs.
Applying Green Organic Chemistry in Springfield College Organic Chemistry Laboratories
Subject: Science (Chemistry)
Presenters: Jade Kiang
Faculty Sponsor:
Marisa Blauvelt
Green organic chemistry works to either reduce or eliminate hazardous substances. In this research project, the 12 Principles of Green Organic Chemistry were further explored through modifying an existing lab experiment conducted at Springfield College to be more green. In particular, the experiment done in this research, Separation of a Three Compound Mixture by Extraction, took into consideration aspects such as prevention of waste (Principle #1), less hazardous synthesis (Principle #3), using safer solvents (Principle #5), and using safer chemistry for accident prevention which follows Principle #12. Diethyl ether was originally used as a solvent, but it was replaced with more tert-butyl methyl ether based on the Pfizer solvent replacement table and GSK solvent selection guide after being checked for solubility. The experiment was successfully completed with naphthalene being the expected end product, despite there being some impurities present and low percent recovery. Therefore, it was possible to adapt one of the organic chemistry experiments currently conducted at Springfield College to be more green by changing the solvent, which means that it may be possible to change other experiments according to the Principles of Green Organic Chemistry. In all, adapting experiments to be more green is important because it aims to reduce pollutants and hazardous chemicals that harm the environment and the organisms within it.
Analyzing the Impact of fGCMs on Both Sexes of Adult Alouatta guariba clamitans in Southern Brazil
Subject: Science (Biology/Chemistry)
Presenters: Lily Depew
Faculty Sponsor:
Dr. Justin Compton and Dr. Melinda Fowler
OBJECTIVE: Fecal Glucocorticoid metabolites (fGCM) are hormones released due to stress that can be extracted to analyze the physiological functionality of adult brown howler monkey (Alouatta guariba clamitans). In this study, I analyzed the association between fGCMs of this species and how stress varied in their reproductive states. I hypothesized that females have higher fGCM levels over males. Understanding stress levels between both sexes of these primates not only helps researchers to identify how stress is managed, but also can be utilized to determine how other species manage stress.
METHODS: This study was conducted using a dataset from (Chaves et. al., 2019b) that collected data on six Alouatta groups; half inhabited large forest fragments while the other inhabited small fragments. Behavioral observations took place in the Atlantic Forest of Porto Alegre and Viamão, Rio Grande do Sul State of southern Brazil. A total of 260 fecal samples were analyzed (32-57 samples per group, 17 females and 10 males,) to obtain their stress levels. Qualitative and statistical analyses were conducted using linear regressions, ANOVA, and T-tests on the software program R to compare stress levels to the sexes, reproductive states, and the amount of time the species moved.
RESULTS: Female’s not only tend to have a higher mean fGCM value than males (females: 80.9, males: 50.5,) but lactating females also have a higher overall mean fGCM value in comparison to the two other reproductive groups (lactating females= 98.8, non-lactating females=67.3, and males= 50.5.)
CONCLUSIONS: Care provided to a juvenile monkey likely increases the stress placed on females. Based on the variables analyzed, females likely carry more of a burden supporting juveniles, while males likely exhibit lower stress when defending their territory. Stress levels may have a greater impact on the health of adult female brown howler monkeys with juveniles.
Keywords: Fecal Glucocorticoid Metabolites (fGCM), Alouatta guariba clamitans (brown howler monkeys), stress, sex roles.