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Art Assists the Science of Smelling.

Achievement/Results

The UC Berkeley CiBER IGERT focuses on biological and bio-inspired motion systems operating in complex environments. We contend that an organism’s function must be understood in the context of its environment. One major focus of our program attempts to understand how organisms sense their environment that can lead to the design of novel sensors of natural odors or contaminants.

CiBER IGERT Trainee Lindsay Waldrop attempts to understand how animals sample odors in both marine and terrestrial environments. Crabs serve as her model organism. Crabs sense chemical signals in their fluid surroundings using chemosensory hair arrays on antennules to discretely sample odor-laden fluid. In other words they sniff. Sniffing occurs when a quick downstroke of the antennule forces water to flow in between the chemosensory hairs and a slower return stroke traps fluid within the array. Crab sniffing relies heavily on a narrow range of antennule velocities and sizes to effectively capture and hold fluid. Therefore, how juvenile crabs sniff is unknown.

Lindsay previously analyzed antennule kinematics and examined antennule morphology using scanning electron micrographs from shore crabs. This year, Lindsay and her undergraduates built seven models spanning a body or carapace width size range of 5 to 25 mm. She used particle image velocimetry (PIV) to visualize flow within the arrays and learned that marine crabs sniff at all stages of life, despite changing Reynolds number, a measure of the ratio of inertial forces to viscous forces, by altering their flicking kinematics and antennule morphology during growth. Lindsay extended knowledge of how crabs sense odors during their lifetimes, how changes in velocity and morphology can mediate size changes due to growth, and how organisms interact with their environments at intermediate Reynolds numbers.

Odor sampling in decapod crabs is not limited to marine environments. Terrestrial hermit crabs of the family Coenobitidae, closely related to marine hermit crabs, use odors to find food and mediate social interactions. This evolutionary transition from water to air resulted in moving their olfactory systems to a fluid which is less dense and in which diffusion of odorants happens much more quickly. Lindsay traveled to French Polynesia to collect terrestrial hermit crabs (Coenobita rugosus) and study their antennules and the motions they produce. She learned that these crabs have arrays of chemosensory hairs that are flat and arranged in a shingle-like pattern, and they wave their antennules in a motion similar to the flicking behavior seen in marine crabs. This year, she wanted to determine whether or not sniffing was lost during this transition to land. She built dynamically scaled physical models of a terrestrial hermit crab antennule based on the morphometrics and kinematics and observed flow using PIV. Lindsay discovered that terrestrial hermit crabs do not sniff, but instead use movement to increase odor transport to chemosensory hairs. In this way, Lindsay extended knowledge in demonstrating a convergence between insect and decapod crustacean olfaction. It is highly likely, that Lindsay’s discoveries can lead to new engineering sensors of both natural odors as well as contaminants in the environment.

To most effectively study the antennules of crabs, Lindsay determined that physical models could be the answer. In the summer of 2010, she contacted The Crucible, a non-profit industrial art and teaching studio in Oakland, CA, regarding scholarship opportunities available for students in science. She explained that she was a graduate student studying olfaction in terrestrial hermit crabs and needed access to glass flame-working facilities to build a model that would help her investigate fluid flow around the olfactory organ of these crabs. They offered to waive her tuition to take a studio lab course during the fall in exchange for presenting her research project and model at their Spring Open House. As a result, she was able to complete her model and the study on hermit crab olfaction and present her research at the Spring Open House.

Lindsay believes working with The Crucible to form a science outreach and creative inspiration program will go further than simply talking to people about her research. By showing people ways that they can harness their creativity to investigate scientific concepts on their own, we can encourage them to learn more about concepts that interest them and science in general. Providing them with both knowledge and confidence with science should help them to become more active members of public discourse surrounding scientific issues. Additionally, the creative outreach program has the potential to encourage young people to understand science in a hands-on fashion and to inspire them into pursuing science as a career by showing them that creativity, curiosity, art, ingenuity, and hard work are as much tools of science as equations, beakers and white lab coats.

Address Goals

Discovery.
Our CiBER IGERT focuses on motion systems operating in complex environments. CiBER IGERT biologist Trainee Lindsay Waldrop attempts to understand how animals sample odors in both marine and terrestrial environments. The majority of research efforts in sensing involve a reductionistic focus on neurophysiology studied in the laboratory. Lindsay’s research has shown that to understand the information obtained in odor sampling, integration with the environment is essential, since it can change the way we interpret neurophysiological data. Her integrative approach using techniques from both biology and engineering, with a consideration of the complex environment, has essentially led to a redefinition of what odor sampling is or in her case what “sniffing” actually accomplishes. Because of the complex morphology of crab antennules, as well as the fluid flow around them, Lindsay has had to go beyond what is possible with current computational fluid dynamic models. She has used an engineering approach to develop physical models scaled appropriately to answer her questions about odor sampling in both air and water. To develop her physical models, Lindsay turned to the art of glass blowing.

Learning.
Art Assisting Science.
Trainee Lindsay Waldrop has taken the interdisciplinary focus of our CiBER-IGERT to the next level. Our program focuses on the integration of biology and engineering. Lindsay has learned that she can venture beyond the scientific disciplines into art. She has seen the possibilities of exchanging novel techniques that can lead to new physical models for biological discovery. At the same time, her unique perspective on the natural world can contribute to artistic expression. This is clearly shown in Lindsay’s participation in an artistic exhibit. The Crucible’s Open House is a free event that welcomes everyone interested in their facility to take a tour, learn about classes and other creative opportunities open to them, and to showcase student artwork and performance. Though it focuses on primarily industrial and fire art, including welding, glass blowing and flame-work, black smithing, and woodwork, the organization is open to all forms of art and is interested in the connection between art and science.

Lindsay was positioned close to the glass flame-working studio and came prepared with a poster explaining her research goals and how they connected with artistic endeavors at The Crucible. She also brought along a terrestrial hermit crab, the model fabricated during her time at The Crucible, and a demonstration of an optics principle that helped her visualize flow around the chemosensory hairs of the crabs’ antennule. She gave a short explanation of her research goals and experimental techniques to visitors and answered questions that they posed about her research, hermit crabs, and working at The Crucible’s glass studio. Over the course of four hours, she spoke with approximately 150 visitors that ranged in age from 4 year-olds to those in their mid-70’s. The response was incredibly positive, many people expressing excitement over both the research and its connection to art and the simple optics demonstration. Some were delighted to see a hermit crab up-close for the first time, including many small children, and to learn more about their natural history.

The excitement generated during the Open House reflected the interest that The Crucible’s staff expressed toward the unique way that her research project used artistic techniques to create scientific knowledge. Lindsay was asked by the Director and Assistant Director of Marketing about advising them on the possibility of starting a campaign that highlights the connection between art and science in a way that would inspire people to use The Crucible’s resources to explore both. She plans to help them develop this program because it represents the unique opportunity to reach out to a demographic of artists and creative people that is typically overlooked by traditional science outreach programs.