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Full-Text Articles in Biology

The Search Of Ancient Life Through The Use Of Geologic Samples, Amber Paturzo Aug 2019

The Search Of Ancient Life Through The Use Of Geologic Samples, Amber Paturzo

STAR Program Research Presentations

The Astrobiogeochemistry Laboratory (abcLab) is interested in exploring molecular and mineralogical biosignatures in ancient and recent Earth samples to provide evidence of early signs of life. Currently, in the abcLab, scientists are utilizing a lipid biomarker extraction and analysis method to remove organic material from geologic samples taken from several sites around the world including Australia, the United States and West Wales. This study focuses primarily on samples collected from the Mochras borehole on the Cardigan Bay Basin, West Wales, dating back to the Early Jurassic to identify biomarkers such as hopanes (derived from prokaryotes) and steranes (derived from eukaryotes) …


Glycolic Acid Utilization In Two Species Of Marine Bacteria, Erik S. Timsak Aug 2019

Glycolic Acid Utilization In Two Species Of Marine Bacteria, Erik S. Timsak

STAR Program Research Presentations

Interactions between bacteria and phytoplankton are crucial for the cycling of organic matter in marine environments. Around 50% of organic carbon taken up by marine bacteria is converted into inorganic carbon. The uptake of organic carbon by marine bacteria exuded from phytoplankton is a key factor in regulating the marine carbon cycle. One such molecule that is exuded by phytoplankton and then uptaken by marine bacteria is called glycolate - the anion of glycolic acid, a two caron molecule. Glycolate is exuded by phytoplankton during photorespiration and 10-50% of dissolved organic carbon in marine environments is comprised of glycolate. Additionally, …


Abundance And Community Composition Of Invasive Intertidal Watersipora On The San Francisco Bay Area Outer Coast, Kevin Myron, Meredtyh Duncan, Jaden Stone, C. Sarah Cohen Aug 2019

Abundance And Community Composition Of Invasive Intertidal Watersipora On The San Francisco Bay Area Outer Coast, Kevin Myron, Meredtyh Duncan, Jaden Stone, C. Sarah Cohen

STAR Program Research Presentations

Invasive species can lead to serious ecological changes. The San Francisco Bay area is one of the most invaded areas in the world due to the commercial shipping industry and recreational water vessels. While the intertidal is not widely invaded, the harbors and docks are. One exception to this is the invasive, colonial filter-feeding bryozoan Watersipora, which has been found at various rocky outer coast sites. Further investigation into how the sites are invaded by this organism and their impact on native species must be carried out. In this project, at four intertidal sites around the SF Bay outflow, we …


Comparing Orientation Behavior And Prey Preference Of Leptasterias Spp. Between Microhabitats, Jenna C. Sanders, Margaret W. Johnson, C Sarah Cohen Jan 2019

Comparing Orientation Behavior And Prey Preference Of Leptasterias Spp. Between Microhabitats, Jenna C. Sanders, Margaret W. Johnson, C Sarah Cohen

STAR Program Research Presentations

Leptasterias spp. is a species complex of small, six rayed, predatory sea stars that inhabit rocky intertidal communities along the Pacific coast of North America. A developmental mode of brooding their young, rather than broadcasting for planktonic development, limits dispersal away from the natal area, and may also result in fine scale local adaptation of populations. Local adaptation may lead to morphological and behavioral differences among populations, specifically towards the most available prey. Within the rocky intertidalthere are zones of high and low wave impact which create microhabitats with their own selective forces. In areas of high wave impact, stars …


Method Development For Structural Assessment Of Nanolipoprotein Particles With And Without Cross-Linked Lipids, Emma J. Mullen, Wei He, Sean Gilmore, Matthias Frank, Matthew Coleman, Megan Shelby Jan 2019

Method Development For Structural Assessment Of Nanolipoprotein Particles With And Without Cross-Linked Lipids, Emma J. Mullen, Wei He, Sean Gilmore, Matthias Frank, Matthew Coleman, Megan Shelby

STAR Program Research Presentations

Membrane proteins make up approximately 30% of the cellular proteome and account for over 60% of pharmaceutical targets.1 Determining the structures of this class of proteins is critical to our understanding of disease states and will advance rational drug design. But membrane proteins have limited solubility, rarely form large crystals that diffract well, and often misfold outside of a bilayer, hindering crystallographic studies.1 Nanolipoprotein particles (NLPs) have arisen as a platform to readily solubilize membrane proteins while mimicking a native lipid environment. NLPs consist of a discoidal phospholipid bilayer encircled by an apolipoprotein belt. In an effort to optimize and …


Impacts Of Nutrient Enrichment On Native And Non-Native Plants In Serpentine Soil, Amber R. Williams, Mary Devlin, N. Rajakaruna Aug 2018

Impacts Of Nutrient Enrichment On Native And Non-Native Plants In Serpentine Soil, Amber R. Williams, Mary Devlin, N. Rajakaruna

STAR Program Research Presentations

Serpentine soil, derived from serpentinite, California’s state rock, is characterized by its harsh nature - due to its low levels of essential nutrients and exceptionally high levels of toxic heavy metals.In California, serpentine soils are characterized by high levels of plant endemism and rarity. Plants occurring in serpentine soil exhibit extreme tolerance of harsh soil conditions, and are typically out-competed in ‘normal’ soils due to the cost associated with physiological specialization. Atmospheric nutrient deposition is contributing to a greater invasion of non-native grass species on serpentine soils, outcompeting the native species and threatening them with local extinction. Our greenhouse study …


Designing An Authentic Behavioral Research Experience In The Classroom Using Siamese Fighting Fish, Betta Splendens, Gianne Souza, Ronald M. Coleman Aug 2017

Designing An Authentic Behavioral Research Experience In The Classroom Using Siamese Fighting Fish, Betta Splendens, Gianne Souza, Ronald M. Coleman

STAR Program Research Presentations

Recently there have been major shifts in biology education towards emphasizing the teaching of the scientific process to more closely reflect actual scientific practices. Authentic research experiences require the development of many higher order cognitive skills. Creating an authentic research experience that appropriately scaffolds the development of these complex skills while engaging individual student motivation remains challenging in classroom settings. Some common challenges include limited time available for working with large numbers of students, cramped working areas, and limited funding and materials resources. Using the Siamese Fighting Fish, Betta splendens, we have created an economically viable authentic animal behavioral …


Ecological And Organic Life Safety Concerns Of Hfo-1234yf, Alberni V. Ruiz Aug 2017

Ecological And Organic Life Safety Concerns Of Hfo-1234yf, Alberni V. Ruiz

STAR Program Research Presentations

While at NOAA my research was directed by the inquiry of whether or not HFO-1234yf, a new compound being introduced into coolant system and replacing greenhouse gases HFC, is harmful to organic life. Using the computer program Matlab I was able to develop figures that represented the concentration of HFO-1234yf (HFO) in 12 different tower locations throughout the country. Comparing and contrasting concentrations of this HFO compound at each site led me to the question the possible harmful side effects this compound could bring to organic life due to the fact that concentration levels are increasing, with one factor being …


Soil Moisture On Soledad Ridge In Santa Rosa Island, Channel Islands National Park, Carrie Fong, Kathryn Mceachern, Ken Niessen Oct 2016

Soil Moisture On Soledad Ridge In Santa Rosa Island, Channel Islands National Park, Carrie Fong, Kathryn Mceachern, Ken Niessen

STAR Program Research Presentations

Santa Rosa Island is one of the Channel Islands off the coast of southern California. Before the island was heavily grazed, Santa Rosa Island is thought to have had large stands of island oak trees, Quercus tomentella, that provided a critical source of water for the ecosystem by creating a “cloud forest”. Wind-borne fog collects on the leaves, branches, and twigs of the island oaks and other native shrubs. Once the water condenses it drips, falls, and soaks into the soil. Introducing cattle and especially sheep to the island has damaged the ecosystem and nearly decimated Santa Rosa Island …


Studying The Effects Of Serpentine Soil On Adapted And Non-Adapted Species Using Arduino Technology, Kiana Saniee, Edward Himelblau, Brian Paavo Oct 2016

Studying The Effects Of Serpentine Soil On Adapted And Non-Adapted Species Using Arduino Technology, Kiana Saniee, Edward Himelblau, Brian Paavo

STAR Program Research Presentations

Abstract: Serpentine soils are formed from ultramafic rocks and are represent an extreme environment for plants. Serpentine soils are unique in that they carry high concentrations of heavy metals, are nutrient deficient, particularly in calcium, and have poor water retention capabilities. Although these soils constitute harsh conditions for plant growth, there are a number of species that are adapted and even endemic to serpentine soil. Water retention by commercial potting mix was compared with serpentine soil. Also, serpentine adapted and non-adapted species were grown in both soil treatments and physiological data were collected. We used the Arduino electronic platform to …


Identification Of Microorganisms Isolated From Mars-Bound Spacecraft Using Maldi-Tof, Melanie K. Phillips Sep 2016

Identification Of Microorganisms Isolated From Mars-Bound Spacecraft Using Maldi-Tof, Melanie K. Phillips

STAR Program Research Presentations

The primary goal of the Biotechnology and Planetary Protection Group (BPPG) at the Jet Propulsion Laboratory (JPL) is to prevent microbial contamination between Earth and other planetary bodies. This helps preserve the ability to study other worlds as they exist in their natural states and protects our biosphere from extraterrestrial life. The process for identifying microbes located on space-bound hardware in JPL can be more efficient and precise by using the technique called matrix-assisted laser desorption and ionization time of flight (MALDI-TOF). Once this identification technique is fully implemented, the process time will be reduced from two weeks to one …


Optimization Of A Genomic Editing System Using Crispr/Cas9-Induced Site-Specific Gene Integration, Jillian L. Mccool Ms., Nick Hum, Gabriela G. Loots Aug 2016

Optimization Of A Genomic Editing System Using Crispr/Cas9-Induced Site-Specific Gene Integration, Jillian L. Mccool Ms., Nick Hum, Gabriela G. Loots

STAR Program Research Presentations

The CRISPR-Cas system is an adaptive immune system found in bacteria which helps protect against the invasion of other microorganisms. This system induces double stranded breaks at precise genomic loci (1) in which repairs are initiated and insertions of a target are completed in the process. This mechanism can be used in eukaryotic cells in combination with sgRNAs (1) as a tool for genome editing. By using this CRISPR-Cas system, in addition to the “safe harbor locus,” ROSAβ26, the incorporation of a target gene into a site that is not susceptible to gene silencing effects can be achieved through few …


The Effect Of Environmental Selection Pressure On The Rate Of Recombination To An Advantageous Receptor Mutation In Bovine Coronavirus, Gavin Schroter, Sally Hall, Mona Hwang, Monica Borucki Aug 2015

The Effect Of Environmental Selection Pressure On The Rate Of Recombination To An Advantageous Receptor Mutation In Bovine Coronavirus, Gavin Schroter, Sally Hall, Mona Hwang, Monica Borucki

STAR Program Research Presentations

Bovine Coronavirus (BCoV) is an important analogue in understanding the effectiveness of zoonotic, single-stranded, positive sense RNA viruses. Many of the most recent viral outbreaks have been attributed to RNA viruses that have one, or more, animal reservoirs [1]. BCoV is such a great candidate for studying these types of viruses because they are from the family Coronaviridae, which also contains the viruses that cause severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS). The goal of this study was to observe changes in genetic makeup of the virus’ outer membrane Spike protein via recombination between two …


Identification And Abundance Of Jellyfish In The San Francisco Estuary, Carrie Fong Aug 2015

Identification And Abundance Of Jellyfish In The San Francisco Estuary, Carrie Fong

STAR Program Research Presentations

In 2010 the delta smelt (Hypomesus transpacificus), became protected under the California Endangered Species Act. Endemic to the San Francisco Estuary, their numbers have been declining since the mid 1990s. Many factors have contributed to their low numbers, such as alterations to their habitat, predation, water diversions, and prey abundance. Several invasive species of jellyfish may be sources of competition for the native delta smelt because they both eat the same food source of copepods. From July 2010 to December 2012, samples of zooplankton, including jellyfish, were taken from 9 different stations in the high and low salinity …


Chemical Oxygen Demand Reduction Using The Algae Dunaliella Primolecta And Chlorella Vulgaris, Angeles L. Mora, Alejandro Hernandez, Alejandro Calderón-Urrea Aug 2015

Chemical Oxygen Demand Reduction Using The Algae Dunaliella Primolecta And Chlorella Vulgaris, Angeles L. Mora, Alejandro Hernandez, Alejandro Calderón-Urrea

STAR Program Research Presentations

Farm industry wastewater is characterized by high organic materials and by high chemical oxygen demand (COD). Farms with large livestock and poultry operations can be a major source of wastewater thus a major concern for effective environmental and industrial management. Effective environmental and industrial management are high in cost therefor biofuels produced from plants have a potential of replacing a portion of fossil fuel consumption with a renewable efficient alternative. Due to California’s water crisis in the recent years, it is questioned if a biological treatment system that uses algal growth to create renewable energy in the form of biodiesel …


Using High Throughput Genomic Sequencing To Predict Ecological Impacts On Sea Turtle Populations, Lesley Anderson Aug 2015

Using High Throughput Genomic Sequencing To Predict Ecological Impacts On Sea Turtle Populations, Lesley Anderson

STAR Program Research Presentations

Marine turtles are long-lived, migratory vertebrates that encounter a variety of human and natural stressors throughout their lives. Understanding the biology and threats of these animals is challenging because they are hard to observe, and can migrate across whole ocean basins. Minimally invasive sampling techniques (e.g., blood samples) allow us to learn about their physiology, genetics, and the environmental conditions they have experienced. In this project, we developed a novel method to extract the RNA from whole green and loggerhead turtle blood from animals inhabiting a variety of sites across the Pacific Ocean. Some habitats are more pristine, while others …


Characterization Of Putative Wnt3a-Inducible Enhancers, Katelynn C. Lee, Nicholas Hum, Aimy Sebastian, Gabriela Loots Aug 2015

Characterization Of Putative Wnt3a-Inducible Enhancers, Katelynn C. Lee, Nicholas Hum, Aimy Sebastian, Gabriela Loots

STAR Program Research Presentations

The Wnt signaling pathway has been previously shown to play a major role in regulating bone metabolism and it is emerging as a target for the therapeutic intervention of bone thinning disorders such as osteoporosis. Several Wnt proteins have been shown to be expressed in bone and mutations in Wnt pathway members such as Wnt co-receptor Lrp5 and Wnt inhibitor Sost have been shown to be associated with low or high bone mass disorders, however, very little is known about specific roles played by different Wnt ligands in bone development, repair and remodeling. To identify downstream targets of Wnt signaling …


Radiocarbon Isotopic Classification Of Deep Tropical Forest Soils, Brooke Butler, Karis J. Mcfarlane, Jennifer Pett-Ridge, Katherine A. Heckman Aug 2015

Radiocarbon Isotopic Classification Of Deep Tropical Forest Soils, Brooke Butler, Karis J. Mcfarlane, Jennifer Pett-Ridge, Katherine A. Heckman

STAR Program Research Presentations

Tropical forest soils have an important role in global carbon (C) stocks. Small changes in the cycling of C could drastically affect atmospheric carbon dioxide (CO2) concentrations and active cycling of carbon in a forest community. Currently, little is understood of how tropical forest soils will respond to the increasing global temperatures. To examine the effects of warming/ drought on losses of older versus younger soil C pools, we implemented radiocarbon (14C) isotopic characterization of various soil plot samples and depths from the Luquillo Experimental Forest, Puerto Rico. 14C was measured using Accelerated Mass Spectrometry (AMS) from catalytically condensed carbon …


Are Circadian Cycles The Dominant Proteome Rhythym In The Intertidal Mussel Mytilus Californianus?, Kristina M. Koster, Cory Elowe, Lars Tomanek Jan 2015

Are Circadian Cycles The Dominant Proteome Rhythym In The Intertidal Mussel Mytilus Californianus?, Kristina M. Koster, Cory Elowe, Lars Tomanek

STAR Program Research Presentations

Mytilus californianus, also known as the California mussel, is a marine bivalve that is abundant along the West coast from Alaska to southern Baja California. They mainly reside in the upper-middle intertidal zone and cling to pier pilings and surf exposed rocks. They create multi-layered beds, which form a habitat for algae and many species of invertebrates. Intertidal mussels live in a naturally dynamic environment. It has previously been reported (Connor and Gracey, 2011) that the 24-hour circadian (day to night) rhythm of the intertidal mussel Mytilus californianus is primarily responsible for its rhythmic gene expression, as opposed to …


Father Convict Cichlids Bite Intruders More Often In Hot Temperatures, Jesse L. Heckendorf Jan 2015

Father Convict Cichlids Bite Intruders More Often In Hot Temperatures, Jesse L. Heckendorf

STAR Program Research Presentations

Convict cichlids (Archocentrus nigrofasciatus) have evolved to be extremely good parents by protecting their brood. Parental care leads to aggressive biting, chasing, and gill flaring to intimidate predators. In this experiment, we show that environmental factors, such as the changing of temperature in this case, affect a male convict cichlid’s aggression toward caring for his offspring when an intruder is introduced. Male convict cichlids attack more in warmer water.


Salinity And Temperature Distribution Of Jellyfish In The San Francisco Estuary, Trisha Huynh, Brooke Bemowski, Lindsay Sullivan, Wim Kimmerer Aug 2014

Salinity And Temperature Distribution Of Jellyfish In The San Francisco Estuary, Trisha Huynh, Brooke Bemowski, Lindsay Sullivan, Wim Kimmerer

STAR Program Research Presentations

Jellyfish are generally characterized by their jelly-like bodies and internal lining (two tissue layers). They found both in the phylum Ctenophora and the phylum Cnidaria. Ctenophores differ from cnidarians primarily due to the rows of “combs”, or cilia, which are used for transportation. Additionally, ctenophores possess sticky cells while cindarians possess stinging cells. Jellyfish depend on zooplankton (small floating aquatic animals) as a food source; as a result, they are potential competitors and predators to plankton-eating fish and may negatively impact fish populations.

As recently as 1950, jellyfish have entered the San Francisco Bay from the Mediterranean Sea (probably …


Growing Conditions For Algae, Angeles Mora, Tamar Melkonian, Alejandro Calderon-Urrea Aug 2014

Growing Conditions For Algae, Angeles Mora, Tamar Melkonian, Alejandro Calderon-Urrea

STAR Program Research Presentations

With the growing demands of water in California and the increasing cost of fossil fuels to operate water-cleaning equipment, Algae was cultivated in different concentrations of Nitrogen, Phosphorus, and Potassium (NPK) during different trails to identify the best growing conditions for the removal water contaminates. Before testing algae in waste water, the Algae: Dunaliella Primolecta, Chlorella Vulgaris, and Scenedesmus Dimorphus were cultivated in four different media containing distilled water and plant vitamins. The different mediums used include: Orchid Grow More (20-20-20), Miracle Grow (30-10-10), Murashige & Skoog, and Orchid Bloom Boster (11-35-15). As a result of the investigation, the algae, …


Xrf Analyses Of Prehanford Orchards, Komal Rana Aug 2014

Xrf Analyses Of Prehanford Orchards, Komal Rana

STAR Program Research Presentations

Subsequent to 1943, the use of Lead Arsenic was banned from the Orchards standing on the Hanford site. This use of Lead Arsenate pesticide was popular among the orchard owners and was dispersed over the site in a myriad of ways. The presence of the traces of lead and arsenic are found today, more than half a century later. Using a portable X-ray florescence analyzer (XRF), the values of lead and arsenic are evaluated while determining the efficiency of the equipment itself. Samples from different decision sites were collected, with lead arsenic values in the low, high and medium range …


Habitat Preference Of The Introduced Green Crab Carcinus Maenas, Brittany Susan Daum, Andy Chang Aug 2014

Habitat Preference Of The Introduced Green Crab Carcinus Maenas, Brittany Susan Daum, Andy Chang

STAR Program Research Presentations

The aim of this experiment was to determine if Carcinus Maenas (European Green Crab) hhas a habitat preference in Seadrift Lagoon located in Stinson Beach, California. This experiment was accomplished by placing crab traps on the two types of substrate in Seadrift (sand and algae). The traps were pulled up every 24 hours and the size and sex of crabs was recorded. The data was analyzed to see if there was a difference in habitat preference based upon size, sex, and number of crabs. Using a Poisson Regression model, the size and sex of crabs were not significantly different between …


Wastewater Filtration Using Dunaliella Primolecta, Scenedesmus Dimorphus And Chlorella Vulgaris, Tamar Melkonian, Angeles Mora, Alejandro Calderon-Urrea Jan 2014

Wastewater Filtration Using Dunaliella Primolecta, Scenedesmus Dimorphus And Chlorella Vulgaris, Tamar Melkonian, Angeles Mora, Alejandro Calderon-Urrea

STAR Program Research Presentations

California is facing a water crisis due to the lack of rain in the recent years. If California continues without rain, California will eventually run out of fresh water. Residents are asked to reduce their intake by a 20% decrease and the cost to consume water is increasing rapidly. At this point, California cannot afford to waste any water. Because of the high demands of water, Agricultural businesses have increased their prices and pay a lot more for extensive water cleaning equipment. In order to recycle water, it is questioned if algae can replace water-cleaning equipment. In order to work …


Life Support: Long Term Storage Of Solid Waste In An Enclosed Membrane System, Emmy O. Trieu, Michael Flynn, Rocco Mancinelli Aug 2013

Life Support: Long Term Storage Of Solid Waste In An Enclosed Membrane System, Emmy O. Trieu, Michael Flynn, Rocco Mancinelli

STAR Program Research Presentations

In deep space missions, maintaining life support is of the utmost priority. In such a closed system, human waste must be stored and treated. Simulated feces (ersatz) will be inoculated with microbes representing normal fecal flora, mixed with urine brine and shredded refuse of products typically used in space missions. Composting methods often use alternating layers of waste with scraps of carboniferous materials (finely shredded refuse). By preparing membrane bags with a homogenized ersatz and carboniferous refuse mixture and membrane bags with alternating layers of ersatz and carboniferous refuse, it may be possible to monitor anaerobic thermophillic digestion of the …


Identifying Molecular Markers Associated With Salt And Boron Tolerance In Poplar Trees, Darshanpreet Gill, Nathan Follen, Davis W. Cheng, Kyan Salehi, Gary Banuelos, James P. Prince Aug 2013

Identifying Molecular Markers Associated With Salt And Boron Tolerance In Poplar Trees, Darshanpreet Gill, Nathan Follen, Davis W. Cheng, Kyan Salehi, Gary Banuelos, James P. Prince

STAR Program Research Presentations

Standard irrigation practices promote salt and boron accumulation in soils on the Westside of Central California. The build-up of these inorganic salts leads to the degradation of arable land and reduction of crop production. Different clones of poplar trees have been shown to grow in salt- and boron-contaminated soils, and in doing so, gradually remove significant amounts of these inorganic salts from the soil. In an effort to identify molecular markers linked with salt and boron tolerance in poplars, 31 PCR primer pairs have been designed based on candidate genes identified from the literature, and an additional 31 PCR primer …


Jellyfish Identification And Quantification In The San Francisco Estuary, Amalia Borson, Lindsay L. Sullivan, Wim Kimmerer Aug 2013

Jellyfish Identification And Quantification In The San Francisco Estuary, Amalia Borson, Lindsay L. Sullivan, Wim Kimmerer

STAR Program Research Presentations

As potential predators and competitors of plankton-eating fish, jellyfish have the potential to negatively impact fish populations. Jellyfish were collected weekly with plankton tows from the RombergTiburonCenterpier in Tiburon, CA. Since some jellyfish were too small to identify, one tow was collected and preserved to record abundances, and a second tow was collected to rear jellyfish until distinguishing characteristics were visible enough for identification. Jellyfish in the preserved tows were then identified, measured, and counted, and their abundance (number m-3) was calculated. Jellyfish from the second tows were reared in plastic buckets that were lightly bubbled using aquarium …


Preservation Of Biosignature Molecules In Potential Sample Return Container Of The Mars 2020 Mission, Kimberly E. Lykens, Fei Chen Ph.D Aug 2013

Preservation Of Biosignature Molecules In Potential Sample Return Container Of The Mars 2020 Mission, Kimberly E. Lykens, Fei Chen Ph.D

STAR Program Research Presentations

Preservation of Biosignature Molecules in Potential Sample Return Container of the Mars 2020 Mission

Kimberly Lykens1 and Fei Chen2

1Wittenberg University, Springfield, Ohio 45501 2Jet Propulsion Laboratory, Pasadena, California, 91109

One requirement for sustainable life on terrestrial planets includes the presence of organic polymers, compounds that are essential for major biological functions such as replication and catalysis. An identified goal of the Mars mission in the year 2020 is to implement a sample-return to identify and validate signs of life on Mars through the discovery of biosignature molecules in Martian core samples. Martian core samples recovered …


Behavioral Variation Between Two Clades Of Leptasterias Spp., Ashley N. Contreras Aug 2013

Behavioral Variation Between Two Clades Of Leptasterias Spp., Ashley N. Contreras

STAR Program Research Presentations

Leptasterias spp. are six-rayed sea stars found along the rocky intertidal of the northeast Pacific Alaska to Santa Catalina Island, southern California. In central California, three clades of Leptasterias are found in separate or mixed populations, in diverse habitats that range from shallow pools of seagrass and algae to bare rock exposed to crashing waves. Initial field observations of two clades from different locations suggested that behavioral variation may relate to habitat differences among clades. To measure differences in activity, the righting response was timed at both field sites. As a result of behavioral variation observed in the field, more …