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Full-Text Articles in Life Sciences

Drone Imagery Of Submarine Groundwater Discharge Effects On Coastal Primary Productivity On Coral Reefs In Maunalua Bay, Hawai'i, Lulu Wang, Florybeth Flores La Valle, Grace Kim Mar 2024

Drone Imagery Of Submarine Groundwater Discharge Effects On Coastal Primary Productivity On Coral Reefs In Maunalua Bay, Hawai'i, Lulu Wang, Florybeth Flores La Valle, Grace Kim

Seaver College Research And Scholarly Achievement Symposium

Submarine groundwater discharge (SGD) plays a crucial role in coastal ecosystems, especially coral reefs, by introducing terrestrial nutrients and freshwater, significantly affecting the primary productivity of coastal ecosystems and potentially altering ecological balances. La Valle et al. (2023) emphasized the importance of SGD in nutrient distribution and algal productivity, highlighting the need for comprehensive understanding and management strategies in the face of increasing nutrient runoff due to land use changes due to increased population. To better understand the impact, our experiments utilize remote sensing and data science by using a DJI Mavic 3 Enterprise drone with a thermal imaging camera …


A Tick's Quest: The Effects Of Climatic Stress On Host-Seeking Behavior Of Wild Ticks, Lawson Trimmell, Peter Briggs, Javier Monzón Mar 2024

A Tick's Quest: The Effects Of Climatic Stress On Host-Seeking Behavior Of Wild Ticks, Lawson Trimmell, Peter Briggs, Javier Monzón

Seaver College Research And Scholarly Achievement Symposium

The Lone Star Tick (Amblyomma americanum) is one of the most epidemiologically relevant tick species in the United States and is experiencing a range expansion. Our study aimed to investigate the effects of climatic stress on the behavior and physiology of the Lone Star Tick at the expansion front. We hypothesized that there are differences in survivorship, questing (host-seeking) behavior, and dehydration tolerance based on sex or geographic origin. We also predicted that ticks increase their host-seeking behavior as they approach death due to dehydration stress. We collected adult ticks from six sites across Oklahoma and New York/New Jersey. We …


Checking For Ticks: Analyzing The Efficiency Of Different Tick Collection Methods, Peter Briggs, Lawson Trimmell, Javier Monzón Mar 2024

Checking For Ticks: Analyzing The Efficiency Of Different Tick Collection Methods, Peter Briggs, Lawson Trimmell, Javier Monzón

Seaver College Research And Scholarly Achievement Symposium

Ticks are the most important arthropod disease vectors in both North America and Europe. Field collection of wild ticks is vital for research on the ecology of vector-borne diseases. Dragging and trapping are the two most common methods for collecting wild ticks. Dragging involves a researcher pulling a canvas through a field to collect ticks searching for a host, while trapping exploits ticks’ natural attraction to carbon dioxide to lure them onto a canvas where they get caught on tape. Our study aimed to evaluate which of these two methods is more effective. We chose six sites across three states, …


Effectiveness Of Frog Skin Secretions Against Uv-B Radiation, Connor Mcgaha, Kinkade Mcmurray, Lee B. Kats Mar 2024

Effectiveness Of Frog Skin Secretions Against Uv-B Radiation, Connor Mcgaha, Kinkade Mcmurray, Lee B. Kats

Seaver College Research And Scholarly Achievement Symposium

As an increasing number of their species face possible extinction, amphibian populations have been steadily declining over the past decades (IUCN). While various factors have been suggested or proven to be partially responsible for this reduction, increased ultraviolet B radiation (UVBR) appears to be one of the more prominent explanations, especially when considering the continual thinning of the Earth’s ozone layer due to anthropogenic climate change. However, it has also been discovered that skin secretions, which are reported to function as a component of amphibians’ innate immune systems, may have an effect on UVBR (Cramp and Franklin). With this in …


Heterospecific Anural Eavesdropping Cues, Lucia C. Maldonado, Hayley Lunn, Max Sprute, Andrew Wang, Ripley Conklin, Nolan Gentile, Conor Kramer, Lee Kats Mar 2023

Heterospecific Anural Eavesdropping Cues, Lucia C. Maldonado, Hayley Lunn, Max Sprute, Andrew Wang, Ripley Conklin, Nolan Gentile, Conor Kramer, Lee Kats

Seaver College Research And Scholarly Achievement Symposium

The ability to communicate within species is a trait utilized by every organism. Using cues conspecifically creates a better chance of survival for other members of the species and increases fitness overall. However, using cues heterospecifically also poses a great advantage as animals can eavesdrop on cues released by another species. Previous studies have recorded that eavesdropping is beneficial to prey species, such as squirrels reacting to bird calls and tadpoles reacting to visual and chemical cues to avoid predation. We asked how one local and one exotic species of frog would respond to cues emitted by another local species …


Substrate Type Affects The Drying Speed And Desiccation Tolerance Of Fern Gametophytes, Jordyn D. Regier, Mayra J. Hernandez, Camille K. Sicangco, Stephen D. Davis, Helen I. Holmlund Mar 2022

Substrate Type Affects The Drying Speed And Desiccation Tolerance Of Fern Gametophytes, Jordyn D. Regier, Mayra J. Hernandez, Camille K. Sicangco, Stephen D. Davis, Helen I. Holmlund

Seaver College Research And Scholarly Achievement Symposium

Although most ferns require abundant water to thrive, some ferns can survive in habitats with limited water. Previous studies have examined the adaptations that allow xeric ferns to thrive in mediterranean-type ecosystems such as southern California. However, the large fern sporophyte only represents one stage of the fern life cycle; the independent gametophyte phase must also survive water stress, including the six-month summer drought periods of the Santa Monica Mountains. Some fern gametophytes have been reported to be desiccation tolerant (capable of recovery from near-complete drying), and this trait is believed to be dependent on the plant’s drying speed. In …


Decline In Amphibian Health In Local Stream, Elyse Vetter, Elise Dearment, Colton Russell, Audrey Fontes, Lee Kats Apr 2021

Decline In Amphibian Health In Local Stream, Elyse Vetter, Elise Dearment, Colton Russell, Audrey Fontes, Lee Kats

Seaver College Research And Scholarly Achievement Symposium

Many local streams of the Santa Monica Mountains are populated by the native California Newt, Taricha torosa, a species of special concern. Arroyo Sequit is one of these streams, the upper and lower portions of which are split by a culvert and the Mulholland Highway. This stream and the surrounding areas burned during the Woolsey fire of 2018. Since the fire, construction has been ongoing in and around the stream. Two years post-fire (during the summer of 2020) significantly more newts were found in the stream than years prior. A large proportion of these newts were unhealthy in appearance, …


Conspecific Aggression Of Invasive Crayfish, P. Clarkii, In Response To Chemical Cues, Elyse Vetter, Elise Dearment, Audrey Fontes, Gary Bucciarelli, Lee Kats Apr 2021

Conspecific Aggression Of Invasive Crayfish, P. Clarkii, In Response To Chemical Cues, Elyse Vetter, Elise Dearment, Audrey Fontes, Gary Bucciarelli, Lee Kats

Seaver College Research And Scholarly Achievement Symposium

Red Swamp Crayfish, Procambarus clarkii, have caused vast damage to the stream ecosystem of the Santa Monica Mountains, following their invasive introduction. Through their extensive eating habits, high levels of aggression, and responsiveness to environmental stimuli, P. clarkii have a tremendous impact on the success of native species in the Santa Monica Mountains. With exposure to chemical cues, crayfish are able to perceive threats and react accordingly. To determine the extent of such chemoreception, pairs of P. clarkii were tested in the laboratory for conspecific aggression in the presence of native newt, native frog, and conspecific alarm cues. The …


The Effects Of Symbiote Ostracods On Invasive Crayfish Behavior, Audrey Fontes, Elyse Vetter, Gary Bucciarelli, Lee Kats Apr 2021

The Effects Of Symbiote Ostracods On Invasive Crayfish Behavior, Audrey Fontes, Elyse Vetter, Gary Bucciarelli, Lee Kats

Seaver College Research And Scholarly Achievement Symposium

Invasive crayfish, Procambarus clarkii, are known to negatively impact the biodiversity of Santa Monica Mountain streams. Small symbiotes, ostracods, live on Procambarus clarkii in some local streams. However, their effect on the behaviour of invasive crayfish is unknown. We used an aqueous chlorobutanol solution to remove ostracods from crayfish. We paired control crayfish with those that had ostracods removed and scored aggressive interactions. Crayfish without ostracods were found to be significantly more aggressive towards crayfish with ostracods. When we compared feeding behavior, we found that crayfish without ostracods consumed food more quickly than control crayfish. We again subjected crayfish …


Arterial Distribution Of The Human Aorta: An Examination Of The Evolutionary, Developmental, And Physiological Bases Of Asymmetry., Brandon Oddo, Cooker Storm Mar 2019

Arterial Distribution Of The Human Aorta: An Examination Of The Evolutionary, Developmental, And Physiological Bases Of Asymmetry., Brandon Oddo, Cooker Storm

Seaver College Research And Scholarly Achievement Symposium

The study of anatomy contends that “form follows function”; a disciplinary theme purporting that anatomical structures (i.e., cells, tissues, and organs) have a shape that serves its proper function. With this in mind, it is unclear why human arterial distribution off the aortic arch is asymmetrical, while the corresponding venous anatomy is symmetrical. We investigated the evolutionary, developmental, and physiological bases for the asymmetry of aortic arch branches in humans. First, we investigated the cardiovascular anatomy of ancestral species to determine if, and at what level, anatomical divergence (from aortic symmetry to asymmetry) occurs. Second, we examined the formation of …


The Effect Of Physical Stress Signals On Conspecific Interactions In Green-And-Black Poison Frogs (Dendrobates Auratus), Gabriella E. Chan, Maxwell A. Kenyon, Summer Ngo, Lee B. Kats Mar 2018

The Effect Of Physical Stress Signals On Conspecific Interactions In Green-And-Black Poison Frogs (Dendrobates Auratus), Gabriella E. Chan, Maxwell A. Kenyon, Summer Ngo, Lee B. Kats

Seaver College Research And Scholarly Achievement Symposium

Amphibian declines have been a major focus of the scientific community for nearly three decades. Many studies describe the leading causes of amphibian decline related to disease, with chytridiomycosis as the most notable example. However, little is known about behavioral conspecific interactions among ill or stressed amphibians, particularly neotropical species. Previous observational research on poison frogs determined that stressed Dendrobates auratus flip onto their backs in a reaction that is similar to fainting in other species. In this study, we examine conspecific interactions of green-and-black poison frogs (D. auratus) with “healthy” and “sick” model frogs, in order to …


The Effect Of Nitrate On The Release Of Glucose Into The Hemolymph Of Crayfish, Procambarus Clarkii, Alec R. Flores, Lee Kats, David Green, Gary Bucciarelli Apr 2016

The Effect Of Nitrate On The Release Of Glucose Into The Hemolymph Of Crayfish, Procambarus Clarkii, Alec R. Flores, Lee Kats, David Green, Gary Bucciarelli

Seaver College Research And Scholarly Achievement Symposium

Pollutants can change the behaviors of invertebrate stream animals. The level of one common pollutant, nitrate (NO3), has been rising in many local rivers and streams throughout the United States due to increases in anthropogenic sources. Nitrate, heavily regulated for its toxic effects to human health, namely the aiding in the development of cancer, also dangerously affects aquatic species by converting oxygen-carrying pigments to forms that are incapable of carrying oxygen. To understand the stress effects of ambient nitrate exposure on P. clarkii, we collected hemolymph samples from red swamp crayfish (Procambarus clarkii) over a 48-hour period after exposure to …


Root Hydraulic Conductance In Malosma Laurina Experiencing Severe Dieback In The Santa Monica Mountains, Natalie M. Aguirre 5861995, Avery Davis, Sarah Nelson Apr 2016

Root Hydraulic Conductance In Malosma Laurina Experiencing Severe Dieback In The Santa Monica Mountains, Natalie M. Aguirre 5861995, Avery Davis, Sarah Nelson

Seaver College Research And Scholarly Achievement Symposium

Malosma laurina is a dominant species in coastal chaparral ecosystems The deep root systems of M. laurina provide structural support for the steep Santa Monica Mountains and allow M. laurina to tap into the deep water table. M. laurina dieback is prevalent in coastal exposures of the SMM, presumably due to historic drought predisposing plant tissues to infection by the fungal pathogen Botryosphaeria dothidea. In ecosystems that experience annual dry periods, a high hydraulic conductance in roots is necessary to provide plants with sufficient water. A recent study has examined the effect of Botryosphaeria on the hydraulic conductance of M. …


An Individual-Based Model Of Chaparral Vegetation Response To Frequent Wildfire, Timothy Lucas, Dayna Mann, Reanna Dona Mar 2015

An Individual-Based Model Of Chaparral Vegetation Response To Frequent Wildfire, Timothy Lucas, Dayna Mann, Reanna Dona

Seaver College Research And Scholarly Achievement Symposium

In recent years, the Santa Monica Mountains (SMM) have been plagued by frequent wildfires which threaten the native chaparral species. Nonsprouting chaparral species are completely killed by a fire, but their seeds germinate in response to fire cues. Facultative sprouters both resprout after a wildfire and release seeds that germinate post-fire. This project is based on data collected since 1986 at a biological preserve adjacent to the Malibu campus of Pepperdine University with an average fire return interval of 7.5 years. We present a spatial model that simulates the growth, seed dispersal and resprouting behavior of individual shrubs that compete …