Month: September 2024

Engineering integrative methods for physiological sensing in whales.

High-resolution biologgers record detailed information about an animal in its natural environment and provide important information about species, like large-bodied whales, that are fully-aquatic and often difficult to observe. While traditional analyses of biologging tag data provide insights about an individual’s three-dimensional movement, recent engineered solutions are enabling direct measurements of physiological parameters, like heart rate, from non-invasive, suction-cup attached whale biologgers. Similarly, an increase in capacity for molecular analysis of tissue samples has uncovered the potential for unique adaptations at the cellular level to support the large body sizes, elevated breath-hold capacities, and extreme seasonal energetics of whales. Combining physiological rate measurements with information about cellular function and whole-organism diving behavior provides an unparalleled opportunity to understand the traits that underpin the extreme physiological function of cetaceans. This seminar will cover the “hows” and “whys” of physiological sensing in whales across multiple scales of biological organization and will conclude with major takeaways as to how these methods could be applied to benefit both comparative physiology as well as conservation and translational medicine.

 

Dr. Ashley Blawas

Postdoctoral Researcher, Hopkins Marine Station

Dr. Ashley Blawas is a postdoctoral researcher in the Goldbogen Lab at Hopkins Marine Station of Stanford University. She completed her B.S.E. in Biomedical Engineering at Duke University and her Ph.D. in Marine Science at the Duke University Marine Laboratory in the Nowacek Lab. She works at the intersection of marine mammal science, engineering, and ecological physiology to investigate the physiological traits that underpin the extreme metabolic function of cetaceans. To date, her work has led to new insights that inform our understanding of basic physiological principles as well as translational medicine and conservation. At Stanford she studies the physiology of baleen whales off the California coast using biologging tags and  has been developing the capacity for physio-logging by engineering novel designs for electrocardiogram (ECG) equipped tags. Her ongoing research also includes understanding the scaling of physiological rates in cetaceans and the molecular drivers of extreme cardiac function in diving baleen whales.

Emperors of the Ice: Physiological Ecology of the emperor penguin

Emperor penguins are the largest species of marine bird, and perhaps because of their size, they are able to fast longer, dive deeper, and endure harsher conditions than any other avian species. As a top predator in the Antarctic ecosystem, they have a significant top-down effect on prey. Additionally, as top predators, their survival and reproduction depend on the functioning of the entire food web.

Join Gitte McDonald as she talks about her research expeditions to the Ross Sea to study the ecology and physiology of emperor penguins. She will start off with an introduction to the basic biology and ecology of emperor penguins before talking about current research on the behavioral and physiological adaptations that allow them to thrive in the Antarctic ecosystem. The talk will conclude with a discussion of current and future challenges. The talk will be heavy on pictures and light on data.

 

Birgitte (Gitte) I. McDonald

Associate Professor, Moss Landing Marine Laboratories

As a physiological and behavioral ecologist, Dr. Gitte McDonald investigates adaptations that allow animals to survive in extreme environments. Marine mammals and birds provide an ideal study system to investigate how animals deal with extreme conditions because of their large size variation, geographic distribution, and physiological challenges they face daily, including hypoxia, extreme temperatures, and fasting. Understanding the mechanisms that allow an organism to interact and survive in its environment is crucial for predicting and potentially mitigating their response to climate change. Currently, her research program focuses on two broad areas of research: 1) determining the diving capacity of breath-hold divers and understanding the underlying mechanisms, and 2) determining the energetic requirements of foraging and reproduction to better understand energy allocation, physiological trade-offs, and the organism’s role in the ecosystem. To address these questions, she uses state-of-the-art biologgers that measure fine-scale diving behavior and physiological variables (heart rate and oxygen), in addition to providing information about the environment.  Her research has provided opportunities to work with a broad range of species in diverse habitats from the Antarctic to the Galapagos.

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Abstract:

The power of science for exploring the world depends on the research tools available and both the imagination and the rigor of the scientists using them. I will present three stories from my career that illustrate 1) the potential of using old tools in new ways, 2) the danger of a vivid imagination without sufficient scientific rigor, and 3) the importance of rigor over peer pressure. As a young marine scientist at UC Santa Cruz, I used SCUBA far offshore to study fragile aggregations of plankton and detritus--the so-call "marine snow" (1). SCUBA provided the manual dexterity and discrimination needed to selectively and carefully take samples, which differed from the traditional bottle-cast or net-towing methods at the time. At the time, this SCUBA sampling pushed the limits of what we knew about micro-environments in the pelagic environment, which expanded our understanding of fragile details on a milliliter scale--a scale relevant to larval fish and many zooplankton. We will discuss the implications and what I learned at NASA about never sending a person to do a job a robot can do better, faster, and cheaper. As a graduate student at Scripps, I considered the sinking of marine snow and studied the potential impact of temperature and pressure on marine bacteria in the Yayanos lab. At the time, a guest scientist, John Baross, was simulating the high temperature and high pressure conditions in hydrothermal vents and claimed to grow bacteria at 250°C and 265-bars pressure--far exceeding the known upper temperature limit of life at the time. Intrigued by his extraordinary result, I rigorously replicated his experiments and showed that all of the results could be explained by artifacts (2). While studying the upper temperature limit of life, I focused on the heat shock proteins (HSPs), that are found in all organisms and known to contribute to acquired thermotolerance. My research into the HSPs in an organism living in near boiling sulfuric acid led to a breakthrough in our understanding of the function of these highly conserved proteins in vivo (3, 4).

1. Silver, M.W., A.L. Shanks, and J.D. Trent. 1978. Marine snow: Microplankton habitat and source of small-scale patchiness in pelagic populations. Science 201: 371-373.

2. Trent, J.D., R.A. Chastain and A.A. Yayanos. 1984. Possible artefactual basis for apparent bacterial growth at 250°C. Nature 307:737-740.

3. Trent, J.D., et al. 1991. A chaperone from a thermophilic archaebacterium is related to the eukaryotic protein, t-complex polypeptide 1. Nature, 354(6353): 490-493.

4. 2003. Trent, Jonathan D., et al. 2003. Intracelluar localization of a group II chaperonin indicates a membrane-related function. Proceedings of the National Academy of Sciences, USA, 100: 15589-15594.

Bio:

After studying marine science at UC Santa Cruz, Jonathan, receive a PhD in Biological Oceanography at Scripps Institution of Oceanography. He conducted postdoctoral research at the Max Planck Institute for Biochemistry in Germany, Århus and Copenhagen Universities in Denmark and the University of Paris at Orsay in France. His research continued at the Boyer Center for Molecular Medicine at Yale Medical School and Argonne National Laboratory before joining NASA Ames Research Center. He left NASA in 2019 on a Fulbright at Akureyri University in Iceland and recently founded UpCycle Systems focused on building sustainable data centers. He is a Fellow at the California Academy of Sciences.