Life Sciences Commons^™

Biomechanics Of Mantis Prey Capture, Danielle S. Taylor

Honors Theses

Mantis species have a variety of different morphologies, so do the extreme forms of mantis limbs trade prey catching capability for camouflage? We hypothesize that some extreme forms of mantis limbs that are associated with cryptic species may be associated with a tradeoff of the capability of those limbs. Previous research has developed 2D morphologies of several hundred species of mantises. We are creating a 3D morphology by using micro dissection, micro CT imaging to construct our 3D biomechanical model. We found the attachment points of the ligaments and muscles from a Tenodera forearm and have constructed a 2D biomechanical …

The Effect Of Blue Mussel (Mytilus Edulis) Extinction On Ecosystem Function In The Gulf Of Maine Rocky Intertidal, Sophia K. Montague

Honors Theses

Stressors associated with climate change including thermal stress and ocean acidification inhibit the growth and reproduction of many species, including the ecologically and economically important blue mussel species in the Gulf of Maine (GOM). Established scaling relationships between mussel size, abundance, and water filtration suggests that the decline of mussels will stunt GOM water filtration. This change in the rate of water filtration could have large effects on the abundance of phytoplankton, abundance of invertebrate larvae, abundance of nutrients and organic material, food web stability, and biodiversity. Overall, this thesis explores the effect of blue mussel (Mytilus edulis) …

Legacies Align With Colby’S Acquisition Of Allen And Benner Islands, Bob Keyes

Colby Magazine

The College creates a 500-acre island campus in Muscongus Bay

Modeling Jadera Haematoloma’S Phenotypic Variation In The Context Of Its Developmental Plasticity, Michael C. Yorsz

Honors Theses

Phenotypic plasticity is the ability of an organism to integrate information from environmental cues to inform the development of its phenotype and remains understudied in biology. Models of plasticity are needed because evolution in the presence of plasticity is poorly understood. Jadera haematoloma, a hemimetabolous true bug, is an excellent animal model of plasticity, exhibiting a non-linear plastic response to juvenile nutrition that biases adult development into groups with differences in flight capability, wing shape, and fecundity. However, there is a lack of literature consensus regarding the range of developmental outcomes in the species. Some publications report the presence …

Impact Of The North American Monsoon On Molt Migrant Passerines, Liuqingqing Yang

Honors Theses

Breeding, molt, and migration place considerable yearly demands on migrating passerines in North America. Due to conflicts in energy allocation, many species have evolved migration strategies that prevent temporal overlap in these processes. However, there is recent evidence that some passerines which breed in western North America migrate to intermediate stopover sites to carry out molt, conflating molt and migration. Factors influencing the evolution of such a strategy are believed to include both aridity on breeding grounds and dependable flushes of late-summer productivity in the southwestern United States and northwestern Mexico. This productivity occurs due to the brisk rainfall of …

Contrasting Patterns Of Nutrient Limitation In The Littoral And Pelagic Zones Of Mesotrophic Maine Lakes, Grace C. Neumiller

Honors Theses

Intense nutrient loading of nitrogen (N) and phosphorus (P) causes sudden regime shifts in freshwater ecosystems from clearwater to turbid conditions with frequent cyanobacterial blooms. Characterization of nutrient limitation patterns of primary productivity in these ecosystems is necessary for effective management of algal blooms. However, much of this research has focused on pelagic habitats. The influence of lake habitat (i.e. benthic littoral versus pelagic zones) on nutrient limitation of primary production in mesotrophic lakes is largely unknown, particularly in contrast to research on pelagic nutrient limitation in eutrophic systems. Using paired nutrient diffusing substrata and mesocosm experiments, we measured chlorophyll- …

Morphological Variance In Mouthparts And Foraging Behavior In Bumblebees, Ye Jin Lee

Honors Theses

Bumblebees (Hymenoptera: Apidae: Bombus) show an incredible degree of size variation within and between species. Individuals from the same hive may vary up to 10-fold in mass. This variation allows individuals to specialize in foraging on different flowers suited to their morphology. However, as different species have different foraging behaviors, their variation in mouthparts and scaling of mouthparts to body size may have been under different kinds of stabilizing selection as they adapted to collect nectar from flowering plants over evolutionary time. Here, we examined the scaling relationships between body size and mouthpart structures, and the variation in mouthpart shape …

Tracking The Endangered Northern Black Racer, Coluber Constrictor Constrictor, In Maine To Determine Areas Of Conservation Importance, Josiah Johnson

Honors Theses

The Black Racer (Coluber constrictor) is a large-bodied snake species found across North America. One subspecies, the Northern Black Racer (C. constrictor constrictor) is listed as endangered in Maine because of its restricted range in York County. Racers have generally been found to prefer open habitats and ecotones, but the specific habitat preferences of racers in Maine is unknown, hindering efforts to preserve habitat for racer conservation. To address this knowledge gap, the Maine Department of Inland Fisheries and Wildlife (MDIFW) has an ongoing project tracking black racer movements in Sanford and Kennebunk, Maine, and I had the opportunity to …

African Savannah Elephant Group Size And Behavior In The Makgadikgadi Pans National Park, Botswana, Katherine S. King

Honors Theses

African savannah elephants (Loxodonta africana), the largest elephant species, influence the structure of the environment they inhabit. Elephants exhibit complex patterns of social behavior between individuals within a population. Many behavioral studies focus on interactions among individuals within a population rather than broader trends related to group size. My study seeks to understand how male African savannah elephant group size is influenced by seasonality, age, physical condition and distance to permanent water resources. I examined the interaction of these variables in two ways: (1) a literature review of elephant behavior and conservation, and (2) an analysis of male …

Insects And The Evolution Of Developmental Pathways: Functional Analysis Of Genetic Sex Determination Mechanisms In Oncopeltus Fasciatus, Josefine Just

Honors Theses

Natural selection alters genetic pathways over evolutionary time. However, different pathways have been shown to maintain mutations at varying rates, leading to different levels of conservation across developmental pathways. Sex determination pathways, in particular, show vast diversity across animals despite the fundamental conservation of biological sex itself. Here, I investigated the sex determination pathway of the hemimetabolous insect, Oncopeltus fasciatus. The large milkweed bug, O. fasciatus, is part of the order Hemiptera, which provides a relevant outgroup study to other insects in which sex determination has been studied to date. I studied three sex determination genes, intersex, fruitless …

New Clues To A Mass Extinction: Colby Geologist Robert Gastaldo And Student Researchers Unearth Evidence That Contradicts Prevailing Models About Ancient Die-Offs, Stephen Collins

Colby Magazine

Colby geologists are rewriting deep time history, altering the script of how scientists understand the mother of all mass extinctions—the End-Permian event that occurred approximately 252 million years ago. Or to suggest that they don’t, in fact, understand it.

Environmental Contingency Of Seed-Fungi Interactions In Coexisting Invasive Purple Loosestrife And Native Cattail, Shayla R. Williams

Honors Theses

Purple loosestrife (Lythrum salicaria) is a highly invasive species able to quickly take over entire wetlands, especially after disturbances. Bountiful seed production and a persistent and prolific seed bank play a key role in loosestrife’s ability to invade. However, some competing native species, such as cattails (Typha spp.) have comparable seed production rates but less abundant seed banks, suggesting that there may be a difference in belowground seed survival. I investigated the abundance of loosestrife and cattail seeds in soils at roadside sites relative to above-ground stem densities. Given the importance of fungal pathogens to seed …

The Effect Of Cyanobacterium Gloeotrichia Echinulata In The Belgrade Lakes, Maine, Harriet T. Rothschild

Honors Theses

Gloeotrichia echinulata is a cyanobacteria species that has been increasingly forming blooms in oligotrophic lakes in the Northeastern United States. The Belgrade Lakes in central Maine have experienced increasing blooms over the past decades. Long Pond and Great Pond in the Belgrade Lakes region are popular locations for summer tourism and year-round residents. Research into G. echinulata is important to the Belgrade community because of potential effects to water quality, public health, and recreation. Studying G. echinulata bloom density throughout the summer and how it may affect the phosphorous cycle, the nitrogen cycle, and the plankton community will help scientists …

School Gardens: Cultivating A Child’S Nutritional Habits, Environmental Knowledge, And Sustainability Practices, Jeffrey Meltzer

Honors Theses

School gardens have existed since the late nineteenth century and today are becoming increasingly popular in many parts of the world, including where I studied in Maine and Australia (AUS). Multiple organizations support school gardens in Maine, including the Maine School Garden Network, which has over 125 registered school gardens. In AUS, the Stephanie Alexander Kitchen Garden Foundation primarily supports the school garden movement and has over 800 registered school gardens. While many researchers have studied school gardens, few have compared two countries, focused on environmental sustainability, or investigated Maine in particular. This thesis combines information from literature reviews, and …

Getting In Deep, Earl Smith

Colby Magazine

Cleaning up Johnson Pond required wading through a quagmire of regulations- and produced some surprising revelations.

The Kennebec River: A Historic Maine Resource, Elise Begin

Historical Ecology Atlas of New England

The Kennebec River has been considered one of Maine’s most important resources for at least the past 6-8 thousand years; its basin is located in west central Maine and drains 5,893 square miles, an area that is approximately one-fifth the area of the state. The river originates at Moosehead lake and runs 170 miles to the Atlantic Ocean. The river can be divided into two basins: the upper basin, which spans from Moosehead Lake to Waterville; and the lower basin, which spans from Waterville to the ocean.

Before the arrival of Europeans in 1606, the Abenaki Indians controlled the entirety …

Bath, Maine: A City Of Ships, Taylor Witkin

Historical Ecology Atlas of New England

Known as Maine’s city of ships, Bath sits on the shores of the Kennebec River, about 15 miles from the Gulf of Maine and 40 miles up the coast from Portland. Though small in population, Bath’s impact on Maine, the rest of United States, and even on the world has been anything but small. Today Bath is known mostly for the Bath Iron Works, which supplies the US Navy with a large portion of its fleets, however, in Bath’s early days it built large, wooden yachts and schooners mostly for trade, not war. The next few pages will explore Bath’s …

The Happy Valley, Cassie Raker

Historical Ecology Atlas of New England

On the Connecticut River in Western Massachusetts, there exists the Happy Valley. Surrounded by the humble Holyoke Range, today you will find a bustling New England settlement dominated by local colleges and universities. But it was not always so. The picturesque Mount Holyoke and its accompanying hotel, known as the Summit House, have overlooked the area for hundreds of years, watching it change from forest to farmland to industry to the modern landscape it is today.

A Postulate For Tiger Recovery: The Case Of The Caspian Tiger, Carlos A. Driscoll, I Chestin, H Jungius, Y Darman, E Dinerstein, J Seidensticker, J Sanderson, S Christie, S J. Luo, M Shrestha, Y Zhuravlev, O Uphyrkina, Y V. Jhala, S P. Yadav, D G. Pikunov, N Yamaguchi, D E. Wildt, J D. Smith, Marker, Philip J. Nyhus, R Tilson, D W. Macdonald, S J. O'Brien

Faculty Scholarship

Recent genetic analysis has shown that the extinct Caspian Tiger (P. t. virgata) and the living Amur Tigers (P. t. altaica) of the Russian Far East are actually taxonomically synonymous and that Caspian and Amur groups historically formed a single population, only becoming separated within the last 200 years by human agency. A major conservation implication of this finding is that tigers of Amur stock might be reintroduced, not only back into the Koreas and China as is now proposed, but also through vast areas of Central Asia where the Caspian tiger once lived. However, under the current tiger conservation …

The Missing Link: The Ecology Of The Serpentine And The Implications For East And North Ponds [Presentation], Colby Environmental Assessment Team, Colby College, Problems In Environmental Science Course (Biology 493), Colby College

Colby College Watershed Study: East and North Ponds (2011, 1999, 1996, 1991)

No abstract provided.

The Missing Link: The Ecology Of The Serpentine And The Implications For East And North Ponds, Colby Environmental Assessment Team, Colby College, Problems In Environmental Science Course (Biology 493), Colby College

Colby College Watershed Study: East and North Ponds (2011, 1999, 1996, 1991)

During the fall of 2011, the Colby Environmental Assessment Team (CEAT) studied the Serpentine connecting East Pond and North Pond. East and North Ponds are members of the larger seven-lake system known as the Belgrade Lakes, located in central Maine. There are over 5,500 lakes in Maine that contribute $6.7 billion to the economy annually through activities including boating, fishing, swimming etc. Additionally, Maine’s lakes are sources of municipal and agricultural water, act as flood buffers, and host a wide range of plant, animal, and fish life. Lakes in Maine are a crucial part society and should be studied and …

Do Male Physiological Condition And Territory Quality Affect Female Choice In The Brown Anole, Anolis Sagrei?, Sarah P. Flanagan

Honors Theses

Female mate choice is an important component of sexual selection because traits that influence male mate preference, such as physiology, and proficiency in acquiring resources, are favored. In lizards, the importance of mate choice remains unclear as reported results from experiments are contradictory. In this study, I investigated whether male physiology and territory quality are important to female mate choice for male Brown Anoles, Anolis sagrei. I tested the hypotheses that female A. sagrei prefer males with greater physiological capacities, and prefer higher quality territories, regardless of male phenotype. To test these, male A. sagrei were first rated for …

Biomass Energy At Colby College, Rachel E. Baron

Honors Theses

In light of growing concern regarding the effects of global climate change, Colby College signed the American College and University Presidents’ Climate Commitment (ACUPCC) in 2008. Through this pledge, Colby has committed to reducing carbon emissions in its Climate Action Plan (IPCC 2007; CCAP 2010). The College seeks to be carbon neutral by 2015 (CCAP 2010). This will be accomplished through a variety of mechanisms, one of which includes the construction of a biomass facility to replace most of the oil currently used for heating (CCAP 2010).

Anthropogenic global climate change has been documented by many scientists, but was widely …

Buffernomics: Assessing Willingness To Pay For Lake Conservation On North Pond And East Pond, Sophie D. Sarkar

Honors Theses

Hedonic property valuations in Maine have estimated that a one-meter decrease in water clarity can reduce shoreline property values by 4 to 16%. To avoid a loss on their lakefront investment, shoreline property owners have a particularly large incentive to conserve lake water quality. Nevertheless, while some shoreline residents voluntarily install vegetated buffers and actively participate in lake stewardship, others continue to ignore shoreline zoning laws at the expense of lake health. In this thesis, I examine the dichotomy of active and indifferent shoreline residents by analyzing the motivations that distinguish residents who are willing to pay (WTP) for and …

Zooplankton Of The Belgrade Lakes: The Influence Of Top-Down And Bottom-Up Forces In Family Abundance, Kimberly M. Bittler

Honors Theses

The purpose of this study was to assess the abundance and family diversity of zooplankton communities in the Belgrade Lakes, and to identify the broad scale and local variables that structure zooplankton communities in this region. The local effects of shoreline development and the presence of macrophyte patches were compared to larger scale variables, such as watershed wide residential development. Zooplankton are an intermediate link in the freshwater food web, and communities respond both to predation pressures as well as nutrient inputs. Shoreline development was expected to influence zooplankton densities by the increased nutrient inputs via erosion off developed sites …

The One That Carries You Away: Essays, Blair S. Braverman

Honors Theses

What is environmental writing? Phil Condon, author and professor at the University of Montana's Environmental Writing Institute, defines it as any piece of writing in which an important factor is nonhuman—be it animal, place, weather, et cetera. At the same time, he acknowledges that the primary limitation of this definition is its lack of limitations; because humans are constantly interacting with—and affected by—the nonhuman, virtually any piece of writing could be considered environmental. The Association for the Study of Literature and the Environment (ASLE), the nation's predominant organization for the academic study of environmental writing, defines itself through its focus …

Impacts Of Shoreline Development On The Littoral Zone Of Great Pond, Problems In Environmental Science Course (Biology 493), Colby College, Colby Environmental Assessment Team, Colby College

Colby College Watershed Study: Great Pond (2012, 2010, 1998)

The Colby Environmental Assessment Team (CEAT) investigated the littoral zone of Great Pond in the Belgrade Lakes region of central Maine. Data collection occurred in September and October and analysis followed in October and November of 2010. Physical, biological, and chemical parameters were assessed to examine the impacts of shoreline development on the health of the littoral community. The littoral zone and adjacent riparian areas were sampled to allow comparison of aquatic and terrestrial parameters among different levels of shoreline development.

Quite A Year And New Life For Panthera Tigris: The St. Petersburg Declaration And The Future Of Wild Tigers, Philip J. Nyhus, Lisa Ann Tekancic

Faculty Scholarship

No abstract provided.

Assessing Genetic Differentiation Among Populations Of The Invasive Plant Impatiens Glandulifera In Maine, Jordan R. Schoonover

Honors Theses

The annual herbaceous plant Impatiens glandulifera Royle is native to the Himalayas and is a significant invasive species in Europe. In the past century, it was introduced to the United States, where it has become established in 12 states. This study evaluated genetic differentiation among four Maine populations, to address a theory that posits hybridization of distinct lineages as a trigger for invasiveness. Regions of microsatellite repeats were evaluated at two polymorphic loci for 41 plants sampled from the four populations. A striking finding was that the observed heterozygosity was substantially higher than the heterozygosity expected from random combination of …

A Watershed Analysis Of Pattee Pond: Implications For Water Quality And Land Use Management, Problems In Environmental Science Course (Biology 493), Colby College, Colby Environmental Assessment Team, Colby College

Colby College Watershed Study: Pattee Pond (2008, 1992)

The Colby Environmental Assessment Team (CEAT) investigated the impact of land use patterns on the water quality of Pattee Pond in Winslow, Maine, during the summer and fall of 2008. Physical, chemical, and biological characteristics of water quality were analyzed to evaluate the current health of the lake. Data collected were compared with previous studies conducted by the Maine Department of Environmental Protection (DEP) and CEAT to examine changes in water quality and land use over time. Trends in Pattee Pond water quality suggest an improvement since the 1970s. However, the lake is still experiencing algal blooms resulting from phosphorus …