Bachelor of Arts (BA), Ohio University, 2024, Environmental Studies

Grassland birds have narrow habitat requirements that are influenced by food availability, habitat composition, and habitat structure. Because survival is influenced by habitat quality and availability, understanding habitat requirements is critical for conservation. I determined how Henslow's Sparrows (Centronyx henslowii) use grassland habitat in the breeding season. In the past 10 years, technology advancements have allowed researchers to study the habitat use and movement ecology of understudied birds, such as grassland birds. I deployed nanotags on 47 adult Henslow's Sparrows at two sites in southern Ohio to determine home range size and habitat use in relation to distance to edge and shrub, as well as the post-breeding dispersal and migratory timing. I predicted that Henslow's Sparrows would use core grassland habitat and avoid edge and shrubs. I found no difference in 95 % home range size between female (0.10 ± 0.03 ha) and male (0.32 ± 0.18 ha) Henslow's Sparrows. Henslow's Sparrows used shrubs when available and edge habitat as refugia after disturbance. I also found that Henslow's Sparrows use fields into August, past dates typically recommended for disturbance (e.g., mid to late July), which suggests the need to leave corridors and patches for refugia after management such as mowing or burning. I determined the fall migratory departure timing of 13 Henslow's Sparrows. I found that Henslow's Sparrows are at risk for entanglement which resulted in mortality of two birds. A third bird found entangled was found alive, entangled in vegetation, and was released after I removed the nanotag. I also found that 24 Henslow's Sparrows were able to remove nanotags and several damaged their nanotags. While I do not recommend the use of nanotags on this species in future studies, my study did result in determining fall migratory departure timing of Henslow's Sparrows in Ohio which was previously unknown.

Committee: Kelly Williams (Advisor) Subjects: Animals; Biology; Ecology; Environmental Studies; Organismal Biology; Wildlife Conservation; Wildlife Management; Zoology

Doctor of Philosophy (PhD), Ohio University, 2023, Biological Sciences (Arts and Sciences)

Chimpanzees (Pan troglodytes ) are a large-bodied, highly adaptable great ape species, characterized by remarkable across-and-within-population variation in habitat use, behavior, and feeding ecology. Chimpanzees are found across the forested mid-region of Africa, occupying a variety of habitat types, though they are frequently described as a rainforest-dwelling species (McGrew, 1979; Russak & McGrew, 2008). Research, however indicates that chimpanzees inhabit a wide range of ecotypes, such as primary and secondary moist lowland forests, swamp forests, submontane and montane forests, savanna woodlands, and occasionally farmland areas (Humle et al., 2016a; Russak & McGrew, 2008). A robust literature derives from chimpanzee field studies conducted in sites across Africa, documenting an array of site-specific strategies for everything from resource extraction to ranging patterns and even patterns of social interactions (Boesch, 2012; Goodall, 1986; Gruber et al., 2012; Herbinger et al., 2001; Matsuzawa et al., 2011; McGrew, 1983). It is thought that many of these behavioral and ecological differences reflect strategies specific to differences in resource availability on different landscapes (Chapman, Chapman, Ghai, et al., 2010; Chapman & Lambert, 2000; Koops, 2011; Krief et al., 2014; Potts, 2008; Potts et al., 2011; Watts et al., 2012). In this dissertation I investigate the interactions of behavior and ecology of a newly habituated chimpanzee community, the Buraiga community, in Kibale National Park in southwestern Uganda. The Buraiga community is estimated to number over 100 individuals, occupying the region with the largest remaining population of eastern chimpanzees, yet one experiencing unprecedented habitat loss due to human population expansion. I characterize habitats within the Buraiga community's range and assess resource availability within these habitats. I document the degree of habituation across Buraiga individuals, examining habitat and diet preferenc (open full item for complete abstract)

Committee: Nancy Stevens (Advisor); Sabrina Curran (Committee Member); Viorel Popescu (Committee Member); Susan Williams (Committee Member) Subjects: Animals; Behavioral Sciences; Biology; Conservation; Ecology; Geographic Information Science; Wildlife Conservation

Doctor of Philosophy, University of Toledo, 2022, Biology (Ecology)

The adverse effects of oil spill disasters on wildlife populations often include mass mortalities and widespread oiling of large numbers of individuals. While these incidents are highly visible and well documented, chronic, long-term impacts on vertebrate species may often persist after the initial oil exposure due to lingering toxins in the environment. These chronic effects may often exceed the short-term impacts caused by initial oil exposure. Additionally, emergency spill response, cleanup operations, and mitigation measures may have additional impacts on populations exposed to oil spills. Species that have long lifespans, late age maturation, and low recruitment rates are particularly vulnerable to population-level impacts if oil spills, and subsequent cleanup operation cause an increase in mortality. Regarding the effects of oils spills in freshwater ecosystems, very little is known in comparison to marine ecosystems. In particular, almost nothing is known about the impacts on freshwater organisms' exposure to diluted bitumen (dilbit) oil. To date, most data on the effects of dilbit on free-ranging freshwater organisms were collected in relation to one of the largest inland oil spills in United States history, the Kalamazoo River oil spill, which spilled between 3 and 4.5 million L of dilbit in Calhoun and Kalamazoo counties, Michigan, impacting 56 km of the Kalamazoo River and the species within. Of the vertebrate species known to have been oiled during the Kalamazoo River oil spill, northern map turtles (Graptemys geographica) were the most observed oiled animal. As a result of the Kalamazoo River oil spill, extensive effort occurred in 2010 and 2011 to clean and restore the freshwater ecosystem impacted by the spill. During 2010, this included the capture, cleaning, rehabilitating, and releasing of more than 2,000 northern map turtles. In 2010, we documented a nearly 6% direct mortality rate (i.e., individuals captured dead, died in care, or transfer (open full item for complete abstract)

Committee: Jeanine Refsnider (Advisor); Richard Becker (Committee Member); Lisa Williams (Committee Member); Henry Streby (Committee Member); William Hintz (Committee Member) Subjects: Animals; Aquatic Sciences; Ecology; Environmental Studies; Toxicology; Wildlife Conservation; Wildlife Management

Master of Science, University of Toledo, 2021, Biology (Ecology)

Habitat loss and fragmentation are two spatial process that can have negative impacts on several aspects of an organism's ecology via changes in the spatial characteristics of a landscape. Spatial structure at the macrohabitat scale, such as heterogeneity and fragmentation by roadways, can affect the habitat use by and the distribution of a population. At a finer scale, habitat composition can impact the population structure of species with temporally variable habitat requirements, such as turtles, which use different habitats for different life activities. In particular, nesting habitat used by turtles can affect multiple life stages, as female face trade-offs in maternal versus offspring survival when choosing a nest-site, and microhabitat characteristics of a nest-site can influence offspring phenotype. Because many turtle species are threatened or endangered and exist in small, isolated populations, characterizing the habitat use with a focus on reproductive activities is critical to conservation efforts. Specifically, identifying the macro- and microhabitat characteristics associated with female survival and nest-success is critical to the implementation of successful conservation plans for these long-lived animals, as population decline in turtles is difficult to recognize before a critical point. Moreover, understanding the relationship between spatial structure and the habitat use of species at the population level is important for site-specific conservation efforts. In Ohio and Michigan, eastern box and spotted turtles are two species of imperiled freshwater turtles which exist adjacent to each other in habitats with varying levels of anthropogenic modification and disturbance. Here I characterized the macro- and microhabitat characteristics of habitat used by adult females of both species. At the macrohabitat scale, I quantified the heterogeneity and fragmentation of habitat available to females, as well as quantified the distance to the nearest roads and (open full item for complete abstract)

Committee: Jeanine Refsnider (Advisor); Jonathan Bossenbroek (Committee Member); Henry Streby (Committee Member) Subjects: Biology; Ecology; Wildlife Conservation; Wildlife Management; Zoology

Doctor of Philosophy, The Ohio State University, 2018, Anthropology

Aye-ayes (Daubentonia madagascariensis) are the most morphologically specialized primates, exhibiting a suite of features that include continuously growing incisors, elongated, clawed digits, large, bat-like ears, and a unique metacarpophalangeal joint in their third digit (Owen 1863; Simons 1995; Soligo 2005). These traits are used in combination to echolocate insect larvae embedded in deadwood, a feeding behavior known as percussive foraging (Erickson 1991, 1995; Erickson et al. 1998). Though aye-ayes were originally thought to be predominantly insectivorous (Petter 1962, 1977), they are seemingly too large (2.6kg) to subsist solely or even largely on invertebrates (Kay 1975). Prior to this study, the only available feeding data were derived from studies conducted on an introduced population from the island of Nosy Mangabe, Madagascar (Iwano and Iwakawa 1988; Sterling 1993, 1994a), and in a disturbed forest (Ancrenaz et al. 1994). The relevance of these studies for understanding the foraging ecology of natural populations in a undisturbed forest is not clear. The present study is the first to be conducted on the diet of a naturally occurring population of aye-ayes in a undisturbed forest for a full annual cycle. For this research, I examined the feeding, ranging, and positional behaviors of three aye-ayes, a male, a female and a juvenile over a two-year period in Torotorofotsy, an eastern rainforest of Madagascar. I also examined the developmental behavior of the juvenile. My results indicate that the female preferentially consumed invertebrates, particularly those contained within live trees. Additionally, the diet of the female and her offspring mainly consisted of two resources, invertebrates and seeds of Canarium trees, unlike previous studies which suggested a diet of at least four main resources (Sterling 1993, 1994a). I found both the female home range (713.6 ha) and the male home range (1587.5ha) to be larger than previously reported (30-98 ha (open full item for complete abstract)

Committee: W. Scott McGraw (Advisor); Dawn Kitchen (Committee Member); Debbie Guatelli-Steinberg (Committee Member); Kristen Gremillion (Committee Member) Subjects: Physical Anthropology

Master of Science (MS), Ohio University, 2018, Biological Sciences (Arts and Sciences)

Roads are ubiquitous in the United States, and their ecological effects are conspicuous. Turtles are among the vertebrate taxa most affected by roads because of their low vagility and use of road and road-side habitats. In 2013, Wayne National Forest in southeastern Ohio was bisected by a new highway, affecting a road-naive population of eastern box turtles (Terrapene carolina carolina), a species of concern in Ohio and vulnerable throughout its range. The goal of this study was to evaluate ecological, physiological, and behavioral effects of proximity to this new road in this road-naive population of turtles. We used a control-impact study to evaluate potential ecological and physiological effects of proximity to roads, employing radio-telemetry to assess space use, movement behavior, and habitat selection. We used novel bioassay techniques to analyze indicators of chronic stress (across the prior several months) using corticosterone stored in nail keratin. Overall, we found no significant differences in home range sizes, habitat preferences, or corticosterone concentrations between road-side and control sites. While our work suggests that proximity to roads has limited indirect influence on the ecology and chronic stress responses of eastern box turtles, and that road-naive turtles demonstrated avoidance of a high-traffic highway, the road network likely continues to contribute to population declines through direct mortality, and further inquiry is needed to assess road effects, particularly in the areas of stress endocrinology and impacts on demography.

Committee: Viorel Popescu (Advisor) Subjects: Animal Sciences; Animals; Biology; Conservation; Ecology; Endocrinology; Wildlife Conservation; Wildlife Management

Master of Science (MS), Ohio University, 2017, Environmental Studies (Voinovich)

Madagascar is home to a broad array of intriguing, endemic, and increasingly endangered species. The fosa (Cryptoprocta ferox) is the largest living (non-introduced) mammalian carnivore on the island and is considered a keystone species for maintaining ecosystem complexity in a broad range of Madagascar's forested habitats. Sadly, the fosa is threatened, with viable populations remaining in only two protected areas. In this context, complex interactions among fosa, prey, and myriad introduced species, reveal a dynamic that is increasingly sensitive to human pressures (e.g., hunting, deforestation for agriculture and fuel wood). This project assembles detailed geographic information to augment long-term data collection and help inform the fosa conservation effort. Research was conducted in Ankarafantsika National Park, a dry deciduous forest in the northwest region of the country, and one of the two places where viable fosa populations still exist. Species encounters and trap rates, roadkill patterns, and the spatial and activity patterns of GPS-collared fosas were analyzed to gather a comprehensive assessment on habitat pressures experienced by the fosa. Species encounter and trap rates documented a shift in prey item encounters over time. Roadkill surveys, together with the roadkill death of one of the GPS-collared study animals, demonstrated failure of current mitigation efforts in addressing roadkill dangers. Fosa space use and activity patterns clearly reveal that they rely almost exclusively upon forested habitats, and that they avoid human settlements. Interestingly, although fosa do rely heavily on forest habitat, their ability to use forest edges and narrow forested strips suggests that corridors may be a viable method to enhance habitat connectivity and promote positive conservation outcomes.

Committee: Nancy Stevens (Advisor); Geoffrey Dabelko (Committee Member); Viorel Popescu (Committee Member) Subjects: Environmental Studies; Wildlife Conservation

Doctor of Philosophy (Ph.D.), Bowling Green State University, 2016, Biological Sciences

Eastern Box Turtles (Terrapene c. carolina) have experienced range-wide declines as the result of extensive habitat loss, fragmentation, and alteration. The Oak Openings Region of northwestern Ohio is a biodiversity hotspot that exists in a highly fragmented landscape and provides a unique case study from which to examine the effects of anthropogenic disturbance on Eastern Box Turtles. In an effort to inform management and conservation efforts in the Oak Openings Region, I initiated a radio-telemetry project with the following objectives: 1) examine the spatial ecology of Eastern Box Turtles over several years to understand how they interact with their habitat in an area as unique as the Oak Openings Region, 2) develop predictive models depicting the temporal distributions of Eastern Box Turtles, 3) examine the impacts of one of the most common management tools in the Oak Openings Region, prescribed fire, on Eastern Box Turtles, and 4) evaluate pattern-recognition software as a low-cost alternative of identifying individual Eastern Box Turtles. Turtles at my study site exhibited larger home ranges than previously reported for this species as well as hierarchical habitat selection at multiple scales. Predicted distributions followed phenological shifts in habitat use and were influenced primarily by habitat type and canopy cover. Prescribed fires have the potential to have a devastating effect on box turtle populations, but management activities that take box turtle ecology into account will minimize these impacts while maintaining a critical disturbance regime. Computer-assisted photo-recognition has a great deal of potential as a supplemental method of identifying box turtles and provides a low-cost means of incorporating citizen science data into mark-recapture studies. My work suggests that conservation for Eastern Box Turtles in the Oak Openings Region should focus on maintenance and restoration of remaining box turtle habitat, connectivity between critical hab (open full item for complete abstract)

Committee: Karen Root Dr. (Advisor); Shannon Pelini Dr. (Committee Member); Jeff Miner Dr. (Committee Member); Enrique Gomezdelcampo Dr. (Committee Member); Salim Elwazani (Other) Subjects: Conservation; Ecology; Wildlife Conservation; Wildlife Management

Master of Science, The Ohio State University, 2015, Environment and Natural Resources

Clean farming practices and forest succession have contributed to population decline of northern bobwhites (Colinus virginianus) across northern portions of their range. Intensively farmed landscapes lack early successional vegetation that provides protective cover near food sources. Earlier research indicated that population growth of northern bobwhites in southwestern Ohio is limited by lack of preferred early successional woody cover during the non-breeding season. I studied vegetation response to removal of large trees from wooded edges (here after edge-feathering) on private owned farmlands in Highland County Ohio. Ninety-nine areas ranging in length from 15 m to 91 m were treated during spring in 2012 and 2013. Vegetation structure and composition of feathered edges was measured before treatment and after 2 growing seasons and in late winter during 2012 – 2014. I used repeated measures analysis of variance to test for differences in vegetation structure and composition among study sites, edge aspects, feathered edge size classes, edge types, and basal area reduction. Basal area reduction differed between years, with a light reduction (29%) in 2012 and a heavy reduction (81%) in 2013. Horizontal, vertical, and ground cover differed among sample periods with the second fall having more vertical and horizontal cover than the first fall, and the first fall having more cover than the first winter. Basal area reduction, size, and sample periods were important predictors of cover measurements. Basal area reduction within woodlot edges or along linear features like fencerows was the most important variable that affected vegetation response to edge-feathering. Basal area reductions between 37 – 50% resulted in positive changes in protective cover for bobwhites after 1 growing season. Large edge treatments with heavy reduction in basal area resulted in net gains in protective cover between seasons, and provided the highest overall change in cover. (open full item for complete abstract)

Committee: Robert Gates Dr. (Advisor); Jeremy Bruskotter Dr. (Committee Member); Thomas McConnell Dr. (Committee Member) Subjects: Animals; Biology; Conservation; Ecology; Environmental Management; Environmental Science; Forestry; Natural Resource Management; Wildlife Conservation; Wildlife Management

Master of Science, The Ohio State University, 2014, Environment and Natural Resources

The Greater sandhill crane (Grus canadensis tabida) historically inhabited Ohio until its extirpation from the state in the 1930s due to habitat loss and unregulated hunting. About fifty years later in the 1980s, the first breeding pair was discovered in Wayne County, OH and the breeding population has since continued to grow and expand. The first systematic study of Ohio's cranes was conducted during 2002-2004 but seasonal movements, habitat selection, and migration behavior were largely unstudied in this breeding population. Road surveys, ground searches, and opportunistic aerial surveys were conducted during 2011-2013 to locate cranes and to determine their local movements and distribution in northeast Ohio. Unison calls were infrequently heard during road surveys and visual observations were rare. Two observations of breeding pairs or family units were made during ground searches and aerial surveys at Killbuck Marsh and Funk Bottoms Wildlife Areas (KMFB) in Holmes and Wayne Counties, OH in 2011, but observations of 11 breeding pairs were recorded in 2012 and again in 2013. Ohio Breeding Bird Atlas II (OBBA II) data also were evaluated to investigate the statewide distribution of the crane population during 2006-2011. One hundred seventy of these OBBA II records included GPS locations. Thirty records were of breeding pairs and 56 were of family units. Forty of the total records were concentrated within approximately 50 km of KMFB. Thirty-one OBBA II recorded sightings were concentrated in northeast Ohio, in Geauga and Trumbull counties; and 20 were concentrated near the marsh refuges of western Lake Erie. Twenty-three cranes were captured and equipped with transmitters during 2011-2013 at KMFB in Holmes and Wayne Counties, OH to track their local movements, seasonal habitat selection, and migration behavior. Cranes followed the general migration path of the Eastern Population of cranes in the Mississippi and Atlantic Flyways. Important stopov (open full item for complete abstract)

Committee: Robert Gates (Advisor); Stanley Gehrt (Committee Member); P. Charles Goebel (Committee Member) Subjects: Ecology; Wildlife Conservation; Wildlife Management

Master of Science, University of Akron, 2013, Biology

In recent decades, the urban landscape has been infiltrated by a species once considered to be intolerant of human activity. The coyote has become one of the largest and most successful carnivore species to inhabit human dominated landscapes throughout North America. Parks and green spaces are important and heavily used habitats for humans and wildlife within urban landscapes but remain a relatively understudied component of urban coyote habitat. Concerns for human and pet safety have resulted in the need to understand the spatial and temporal relationship between humans and coyotes in recreational parklands. We examined the potential conflict that exists between coyotes and humans in recreational parklands by investigating the temporal relationship of humans and coyotes along designated recreational trails. In addition, we also examined the spatial relationship of coyotes in proximity to trails. Specifically, we predict that coyotes will shift their activity to more nocturnal periods, and avoid areas of intense human use, particularly designated recreational trails, as a function of human activity occurring within the study area. In order to test this relationship, human and coyote activity was quantified within the Cuyahoga Valley region of northeast Ohio from 2009 through 2012. The study area is 14,052 hectares of public land maintained by the Cuyahoga Valley National Park and adjoining Cleveland Metroparks, and Metro Parks, Serving Summit County. It is located within the Cuyahoga River Watershed in Northeast Ohio between the cities of Cleveland in the north and Akron to the south. The study area receives over 2.8 million visitors a year, and has over 120 kilometers of designated recreational trails. Human use was monitored throughout the study area with infrared trail monitors installed at designated trail heads in 2012, and supported with data collected from traffic monitors installed in parking lots from 2008-2012. As expected, human activity (open full item for complete abstract)

Committee: Stephen Weeks Dr. (Advisor); Gregory Smith Dr. (Committee Member); Randall Mitchell Dr. (Committee Member); Stanley Gehrt Dr. (Committee Member) Subjects: Animal Diseases; Animal Sciences; Animals; Area Planning and Development; Behavioral Sciences; Behaviorial Sciences; Biology; Conservation; Ecology; Forestry; Geographic Information Science; Natural Resource Management; Wildlife Conservation; Wildlife Management

Master of Science, The Ohio State University, 2011, Environment and Natural Resources

The majority of the summer range of the Indiana bat (Myotis sodalis) is within agricultural areas, yet despite known negative effects of agriculture, few studies have examined the ecology of the Indiana bat within a highly agricultural landscape. To evaluate the effects of agriculture on Indiana bats I asked the following questions: 1. Do Indiana bats selectively use habitat within an agriculturally-dominated landscape? 2. Do Indiana bats select habitat differently at different spatial scales within an agricultural landscape? And 3. Do Indiana bats select and use habitat within an agricultural landscape differently than other areas of their range? From a study area along Big Darby Creek in Pickaway Co. Ohio USA, I captured 60 Indiana bats (including five recaptured bats) July-September 2008, April-September 2009, and April-September 2010. I calculated home ranges of 32 individuals that had an average area of 210.5 ha ± 130.6 SD. I used distance based analysis to evaluate habitat selection within the home range, and at 1200 m and 4000 m spatial scales. At each scale, bats selected areas closer to forest and open water and farther from cropland than was expected by chance. The bats heavily used the wooded creek corridor, but also utilized wooded patches in upland areas. I tracked 51 bats to 56 roost trees 474 times. The bats used roost trees in a variety of locations and across a broad area. Most roost trees were located within the wooded creek corridor, but seven were more than 1 km from open water. I evaluated the location of roost trees within the landscape at 1200 m and 4000 m spatial scales. Roost trees were not located randomly at either spatial scale. The only significant factor in both cases was the distance to open water. There was also was a significant difference in physical characteristics of used and available roost trees (A = 0.257, P = 0.025) and primary and secondary roost trees (A = 0.032, P = 0.013). Widely scattered roosts suggest Indiana bat coloni (open full item for complete abstract)

Committee: Stanley D. Gehrt PhD (Advisor); Roger A. Williams PhD (Committee Member); Paul G. Rodewald PhD (Committee Member) Subjects: Ecology; Wildlife Conservation; Wildlife Management

Master of Science, The Ohio State University, 2008, Natural Resources

There is a paucity of information concerning badger ecology on the eastern extent of the species range. To fill these knowledge gaps, this study focused on assessing certain aspects of badger ecology in areas dominated by agricultural use in Ohio and west central Illinois. Badger state-wide badger distribution in Ohio was determined through the collection of badger observations using a publicity campaign. Overall, 387 badger observations were collected: unconfirmed reports were most numerous (43%), followed by probable (32%), and confirmed (25%). Relatively few observations were recorded until the early 1990s when they began to increase, and sharply increased during the 3-year study period. Badgers were recorded in 56 counties, but most (>99%) of observations were found in 53 counties above the glacial line. Multi-scale spatial ecology and habitat use was evaluated using radiotelemetry data for badgers in Ohio (n = 5) and Illinois (n = 14) and an independent set of badger observations in Ohio. Mean 95% FK annual home ranges in Illinois were larger than in Ohio, but mean 50% FK annual home ranges did not differ between states. Mean 95% FK annual home ranges for males were larger in Illinois than in Ohio; however, male 50% FK and both female annual home ranges did not differ between states. Both male home range sizes did not differ from females in Ohio, but 95% and 50% FK were larger for males than females in Illinois over annual periods and during the rearing season; the 95% FK was also larger for males than females in Illinois during the breeding season. Badgers in both states selected agricultural habitat within their home ranges, and linear grassland and wetland-associated habitats within the study area landscape. Ohio badger observations showed badger occurrence was associated with interspersed blocks of agriculture and linear grassland habitats. The habitat-relative abundance of badgers in Ohio was determined through an independent set of badger observations (open full item for complete abstract)

Committee: Stanley Gehrt (Advisor); Darla Munroe (Committee Member); Amanda Rodewald (Committee Member) Subjects: Ecology

Master of Science, The Ohio State University, 1989, Zoology

Committee: Theodore Bookhout (Advisor) Subjects:

MA, Kent State University, 2007, College of Arts and Sciences / Department of Anthropology

Mammal brains may evolve through selection on specific neural structures. Thus, they may be under varying evolutionary pressures. This study investigates the effect of environmental influences, such as diet, home range size, activity pattern and habitat, on primate hippocampal volume size, which appears to be responsible, in part, for spatial memory skills. In both species and phylogenetic independent contrast analyses, a highly frugivorous diet had no impact on hippocampus volume size. Due to exceptions to the rule that primates with mainly insectivorous diets tend to be smaller-bodied, log body mass was plotted against percentage of frugivorous diet. When frugivorous-insectivore outliers were removed, the size-adjusted hippocampus volume residual from medulla oblongata volume was found to increase in primates with a highly frugivorous diet. Conversely, primarily insectivorous primates demonstrated a negative correlation with hippocampal size, suggesting they have smaller hippocampi than folivorous or frugivorous primates. In addition, hippocampus volume was shown to increase as home range size increased. Diurnal and nocturnal activity patterns as well as arboreal, semi-terrestrial and terrestrial habitats had no effect on primate hippocampus volume size. These results suggest that environmental pressures involved with diet and home range size may selectively pressure for an increase or decrease in primate hippocampus size due to its role in spatial memory. This is the first study to demonstrate a selective environmental pressure on primate hippocampus volume size.

Committee: Chet Sherwood (Advisor) Subjects: Anthropology, Physical