Nalini Polavarapu is the chief of data science strategy of a Fortune 500 pharmaceutical. Sadaf Kazi is a research scientist helping to improve the safety of health care systems. Ryan Hynd and Denise Okafor found themselves in academic careers close to the degree they earned at Georgia Tech. Colin Blenis and Jayda Nail used their Georgia Tech science education to enter medical professions.
All of them used their College of Sciences degrees to make a difference in their professions. For some, that path took a turn because of what they learned about science – and themselves – at Georgia Tech. Six College of Sciences alumni share their memories of life at Georgia Tech, the lessons they learned that they applied in their careers, and what they would tell current students about how to make the most of their time in the College of Sciences.
On the heels of the 2019 Ig Nobel Prize in Physics, two more awards have been bestowed on David Hu, professor in the Schools of Mechanical Engineering and of Biological Sciences, adjunct professor in the School of Physics, and researcher in the Petit Institute for Bioengineering and Bioscience. The American Institute of Physics (AIP) selected Hu as co-winner of the book award for its 2019 Science Communication Awards. Organizers of China’s Pineapple Science Prizes have named Hu this year’s winner of the physics prize.
Understanding Animal Locomotion
AIP’s annual awards recognize journalists, authors, reporters and other diverse writers for their efforts in science communication.
Hu’s “How to Walk on Water and Climb Up Walls,” published by Princeton University Press, is one of two winners of AIP’s 2019 book award. “Hu’s book explores the astounding diversity and versatility of animal locomotion and how engineers are inspired by it as they design robotics. His team discovered how dogs shake dry, how insects walk on water, and how eyelashes protect the eyes from drying,” AIP said in a press release.
“A lot of people ask me where I get my ideas. I like to study things that relate to everyday life,” Hu told AIP. “I get inspiration from raising my children. From a diaper change with my son, I was inspired to study urination. From watching my daughter being born, I was inspired by her long eyelashes.”
According to AIP, “Judges praised Hu’s book for featuring an interdisciplinary group of scientists working the front lines of their fields.”
“I am honored to receive this award and to join the line of science communicators who have been recognized since the 1960s,” Hu says. “I was diligent about getting a diverse representation of scientists in my book, and I interviewed more than 30 scientists over three years to get that feeling. I think it takes a range of approaches to understand nature, and I wanted to convey that to the reader.”
Sparking Public Enthusiasm for Science
Meanwhile in China, organizers of the Pineapple Science Prize have named Hu the winner of the 2019 prize for physics. The prize recognizes researchers whose great imagination arouses the public’s enthusiasm for science. This is Hu’s third Pineapple Science Prize.
In 2015, Hu received the Pineapple Science Prize in physics for the work “Mosquitoes survive raindrop collisions by virtue of their low mass.” The insects “have extremely strong exoskeletons and are good at tai chi, dropping a little with the raindrop to discharge the force,” Hu said at the time.
The discovery explains how small insects such as mosquitoes survive outdoors where air is moving fast or heavy rain is pouring. The finding suggests that the smaller an organism is, the stronger it is, Hu said. “They have some unforeseen advantages that really can't get destroyed even if you hit [them] very hard."
In 2016, Hu won again, this time in biology, for the work “Cleanliness is next to godliness,” about the mechanisms animals use to keep clean. In particular, why do flies rub their legs? They use the hair on their legs to brush off the dirt on their bodies. This mechanism could be used to keep solar panels clean, Hu said at the time.
This month, Hu returned to China to collect the 2019 Pineapple Science Prize in physics. The award is for the work “Cats use hollow papillae to wick saliva into fur,” which explains the workings of cats’ tongues.
“This work shows that cats clean their bodies using the hollow spines on their tongue,” Hu says. His team 3D scanned and 3D printed the spines on the cat’s tongue and imbedded them into a bioinspired hairbrush. “The brush experiences lower grooming forces and could be used to apply medications or hair products directly to hair with a minimum of water or product. It is by using these spines that cats can groom with only two tablespoons of saliva per day,” Hu says, whereas humans use 10 liters of water for a shower.
"Without awards like these, curiosity and science-minded thinking can be blown to smithereens by political winds."
Keeping Curiosity Alive
“The judges at the Ig Nobels, AIP, and the Pineapple Science Prizes are encouraging curiosity and enjoyment of science by the general public,” Hu says. “Curiosity is like a flame. It can be easily snuffed out if not encouraged. Without awards like these, curiosity and science-minded thinking can be blown to smithereens by political winds.”
Hu adds: “I am glad that China is taking care of the next generation of scientists by keeping their award alive. It’s good for China to be seen by the world as having a sense of humor.” Hu donned a giant cat costume at the award ceremony in China on Oct. 26.
Hu couldn’t have done all this work just by himself. “Two Ig Nobel Prizes and three Pineapple Science Prizes wouldn’t be possible without my great group of Georgia Tech graduate students and undergraduates who volunteered to be urinated on by elephants, bitten by mosquitoes, and licked by cats,” Hu adds.
Hu earned a doctorate in mathematics and a bachelor’s degree in mechanical engineering from Massachusetts Institute of Technology. He is a recipient of the National Science Foundation CAREER award for young scientists. Hu’s work has been featured in The Economist, The New York Times, Saturday Night Live, and Highlights for Children. He is originally from Rockville, Maryland.
When the National Science Foundation and the Simons Foundation launched the Research Centers for Mathematics of Complex Biological Systems (MathBioSys) initiative two years ago, the idea was to bring two distinct disciplines together to enable creative, collaborative research, and ultimately to develop the next generation of researchers who would work seamlessly at interdisciplinary crossroads—researchers like Kelimar Diaz.
Diaz is a Ph.D. student in the Quantitative Biosciences (QBios) program at Georgia Tech, and part of the first wave of junior researchers in the Southeast Center for Mathematics and Biology at Tech, one of the four research centers funded by the NSF and Simons. She’s working in the lab of Dan Goldman, professor of physics, member of the Petit Institute for Bioengineering and Bioscience and a team lead at SCMB. Diaz is exactly the kind of trainee that SCMB and the national endeavor needs, exemplifying the kind of interdisciplinary acuity necessary to do innovative research at the intersection of mathematics and molecular, cellular, and organismal biology.
Diaz comes by her wide-ranging interests naturally. Growing up in Puerto Rico, she used to follow her father around on his small farm, surrounded by animals and plants, “learning as much as I could,” she says. “Over time, I was convinced that I would eventually pursue undergraduate studies in biology.
“However, this plan changed abruptly when I took my first physics course in 12th grade,” Diaz added. “Physics felt like my ‘calling,’ but living systems remained at the core of what I care most passionately about. When it came to applying to graduate school, it seemed like an obvious choice: to join a Physics Ph.D. program with faculty that carry out research of physics of living systems.”
That made Goldman’s biomechanics lab and the QBioS program perfect fits for her interests. “Tackling biosciences questions with quantitative approaches is intuitive to me,” she says, adding that the SCMB is taking the integrative approach to another level. “Collaborating with people that have a background in math can bridge gaps between biology and math to develop and use mathematical tools to study underlying processes in biology. This is an opportunity to drive both fields forward. As math is further developed to study biology, a repertoire of tools will be available for researchers to use in the biomedical field.”
Diaz sees herself as part of the vanguard in one of the newest interdisciplinary approaches to understanding the depth and breadth of living systems. And she’s got some good company in the first cohort of SCMB junior researchers, an international group of eager, talented young investigators, like Margherita Maria Ferrari, a postdoctoral researcher from Italy with a classical mathematical training in analytics and statistics.
“During my Ph.D., I went to a conference and met a professor who was giving a talk about mathematics applied to biological processes and chemical processes, which I thought was very interesting, and unexpected,” says Ferrari, who had not been exposed to this kind of integrative research before. “I learned that there were people using tools that I was familiar with, but in a completely different research area.”
So after earning her Ph.D., she sought opportunities that would satisfy her growing interest in this kind of integrative research, and found her current post in the lab of Nataša Jonoska, professor at the University of South Florida and an SCMB team lead.
Ferrari, Diaz, and their fellow junior researchers had a chance to gather and formally meet each other, along with the fourteen faculty team leads and administrators of SCMB, at a center-wide meeting held on September 13 on the Georgia Tech campus. “It was nice to meet all the other researchers and have the chance to give informal presentations of our projects, and to really get an idea of what the center is doing, up close,” Ferrari said.
While the meeting at Tech provided a way for SCMB members to meet and work in person—and a number of junior researchers bonded on Tech’s leadership challenge course while on campus—they’ve been gathering on a regular basis virtually since the center was launched last year. Since this is a center comprised of institutions from across the Southeast, they meet monthly; Georgia Tech personnel gather in one room, and everyone else joins via video conference.
“It was fantastic to have everybody in one space, to hear directly from the junior researchers about the progress of each seed project,” said Annalise Paaby, an SCMB team lead and assistant professor of Biological Sciences at Tech, and a researcher in the Petit Institute. Each project is a collaboration between a faculty member and a trainee from the math side, and a faculty member and trainee from the bio side. “The seed projects have been cooking for a while now, and the trainee pairs gave short, pecha kucha style research reports—so we had a lot of fun with questions and discussion.”
For Kelimar Diaz, SCMB and its interdisciplinary opportunities represents the new leading edge of bioresearch, and will help provide a roadmap for her own future.
“I have not decided what kind of career path to take after I finish my Ph.D., but I believe that the way things are structured in SCMB, I will end up with a repertoire of skills that will allow me to pursue the career of my choosing,” she says. “I am contributing to driving biology and math forward. The Center and all of its members are advancing our knowledge of the living world quantitatively, while providing insight to biological applications and expanding math.”
Meet the first class of SCMB junior researchers who will be advancing that knowledge:
Hector Baños earned his bachelor degree in applied mathematics at Universidad Autónoma de Querétaro in Mexico, then earned a master’s degree in mathematics and statistics at then his Ph.D. in mathematics the University of Alaska (Fairbanks). Now a postdoctoral researcher in the lab of Christine Heitsch, mathematics professor at Georgia Tech and director of the SCMB (and also a Petit Institute researcher), he’s working on an SCMB seed project called “RNA structural ensembles in evolution,” a collaboration between Heitsch and Annalise Paaby, assistant professor in the School of Biological Sciences at Tech. As he and his fellow researchers work to uncover the processes behind evolution in the species and molecular levels, he’ll work on models for secondary structure inference.
Keisha Cook earned a bachelor’s degree in mathematics at the University of Alabama, where she stayed on to earn both a master’s and Ph.D. in applied mathematics. Now a postdoctoral researcher in the lab of Scott McKinley at Tulane University, she’s working on a SCMB seed project entitled “Stochastic modeling in cellular internalization and transport,” a collaboration between McKinley and the lab of Christine Payne at Duke University. “My ultimate research goal is to become well versed in many applications of mathematics and cell biology, in order to teach mathematics students how to speak the language of a scientist,” said Keisha, who will analyzing particle tracking data (collected in the Payne Lab) using probabilistic and statistical methods to provide greater insight into the functions of intracellular particle motion.
Daniel Cruz, who earned both his bachelor’s degree (mathematics with a minor in computer science) and Ph.D. (mathematics) at the University of South Florida, is now a postdoctoral researcher at Georgia Tech, though his primary advisor is Elena Dimitrova, currently at California Polytechnic State University but until recently at Clemson University. His SCMB seed project is a collaboration between Dimitrova and Petit Institute researcher Melissa Kemp, associate professor of biomedical engineering at Georgia Tech, and it’s entitled “Modeling emergent patterning within pluripotent colonies through Boolean canalizing functions.” He’s primarily interested in using discrete models to understand how self-assembly and self-organization arises from molecular and/or cellular interactions. “I’m a math postdoc studying how boolean networks and other discrete models can improve our understanding of pattern and structure formation resulting from the differentiation of pluripotent colonies,” he said.
Kelimar Diaz earned her bachelor degree in physics at the University of Puerto Rico (Rio Piedras campus). Now, as a Ph.D. student based in the lab of Dan Goldman, professor in the School of Physics at Georgia Tech, she’s working on an SCMB seed project called “Optimization of limbless locomotion via algebraic kinematics,” a collaboration between Goldman and Greg Blekherman at Georgia Tech. She plans to satisfy her interest in biomechanics an locomotion by exploring undulatory locomotion across length scales to understand control principles.
Margherita Maria Ferrari, a postdoctoral researcher, earned an undergraduate degree and a master’s degree in mathematics at Università degli Studi di Modena e Reggio Emilia in Italy, and her Ph.D. in mathematical models and methods in engineering at Politecnico di Milano. Based in the lab of Nataša Jonoska at the University of South Florida, her SCMB seed project, “Discrete and topological models for DNA-RNA interactions,” is a collaboration between that group and the lab of Petit Institute researcher biologyFrancesca Storici, an associate professor of biology at Georgia Tech. My goal is to develop and apply mathematical tools to advance our understanding of biological and chemical processes,” she said. “My role is modeling RNA structure formation and R-loop structures, which we feel will help us in describing the process of DNA double-strand break repair.”
Gemechis Degaga, who earned his Ph.D. in theoretical chemistry at Michigan Technological University, is currently based at Oak Ridge National Laboratory in the lab of Julie Mitchell, director of the Biosciences Division. His SCMB seed project, entitled “Identifying disorder-to-order transitions in post-translationally modified proteins,” is a collaboration between Mitchell and the lab of Matt Torres, associate professor in the School of Biological Sciences at Georgia Tech (and a Petit Institute researcher). “My main research interest involves the use of machine learning models to understand protein folding,” he said, describing his role in the project as building “generative adversarial artificial neural networks to learn, predict, and generate new protein sequences which form beta-hairpin secondary structure.”
Youngkyu Jeon, who earned a bachelor of science in life sciences at Korea University, is a Ph.D. student currently based in the lab of Francesca Storici, associate professor in the School of Biological Sciences at Georgia Tech. He contributes to the seed project on DNA-RNA interactions with Storici, Jonoska and Ferrari. The goal is to understand the topology of RNA-mediated DNA modification and/or repair, which Youngkyu is studying through experiments based on mathematical modeling.
Wei Li, a postdoctoral researcher in the lab of Matt Torres at Georgia Tech, earned her Ph.D. from Wake Forest University. She’s contributing to the SCMB seed project on protein disorder-to-order transitions with Torres, Mitchell and Degaga. Wei’s role is to test candidate proteins using experimental spectroscopic methods, testing for impacts on biological function.
Bo Lin, who earned a Ph.D. in mathematics at the University of California-Berkeley, is now a postdoctoral researcher in the lab of Greg Blekherman, associate professor of mathematics at Georgia Tech, where he’s working on the SCMB seed project on limbless locomotion with Blekherman, Goldman and Diaz. Basically, Lin is using his expertise in math to analyze data generated from biological experiments.
Eunbi Park, who earned her undergraduate degree in agricultural science from Kyungpook National University in Korea, is now Park a Ph.D. student in Bioinformatics at Georgia Tech in the lab of associate professor of Biomedical Engineering, contributing to the seed project on modeling emergent patterning within pluripotent colonies with Kemp, Dimitrova, and Cruz. Park collects fluorescent microscopy images of live, dividing stem cells, generating time-lapse movies that capture the behavioral dynamics of the cells. With the input of Cruz and Dimitrova, she is using agent-based models to define that behavior mathematically.
Nathan Rayens earned two bachelor degrees at Miami University: one in mechanical engineering and manufacturing engineering, and another in music. Now a Ph.D. student in mechanical engineering and materials science, he’s based in the lab of Christine Payne at Duke University. Now he is working with Payne, McKinley and Cook on the seed project modeling cellular internalization and transport. Rayens said, “this is the first time I’ve been involved in biological research, so my current goal is to learn as much as I can. I’m currently working on analyzing cell samples incubated with and without TiO2 to evaluate lysosome trajectories and see the effect of nanoparticles on cell transport.”
Ashleigh Thomas, who earned an undergraduate degree in electrical engineering and math at the University of Pennsylvania, got her master’s and Ph.D. in mathematics at Duke University. Now based in the lab of Peter Bubenik at the University of Florida, she’s working on an SCMB seed project entitled, “Topological data analysis to understand genetic control of morphological phenotype,” a collaboration between Bubenik and Hang Lu, professor in the School of Chemical and Biomolecular Engineering at Georgia Tech.
Ling Wang, who earned both her bachelor and master’s degrees in biological science at Georgia State University, is a Ph.D. researcher in the lab of Annalise Paaby, assistant professor in the School of Biological Sciences at Georgia Tech. Her work is in collaboration with Paaby, Heitsch, and Baños on the RNA folding seed project. Wang’s ultimate research interest is in combining computational and biological approach to study how RNA folding structure matters in biological evolution and she’s currently working with Paaby, “to design experiments to test if RNA’s secondary structure will have an impact on early-stop codon readthrough, and ultimately determine its impacts on biological functions.”
Keren Zhang earned his undergraduate degree in chemical engineering at the University of California-Berkeley. Now he’s a Ph.D. student in the lab of Hang Lu at Georgia Tech, where he’s working with Lu, Bubenik and Thomas on the seed project studying morphological phenotype with topological analysis. Zhang’s goal is to establish pipeline methods to quantify the developmental plasticity in the C. elegans connectome.
A College of Sciences staff member, Chung Kim, has won quiz 6 of ScienceMatters Season 3. Chung is an academic program coordinator in the School of Biological Sciences.
Chung has worked in higher education for the past six years. She has served a advisor for study-abroad programs and for international admission. In the School of Biological Sciences, she serves as academic advisor for graudate students, particularly in the programs for applied physiology, biology, and ocean science and engineering.
Originally from Seoul, South Korea, Chung grew up in Korea, the U.S. and India. She moved to Georgia with her husband in 2012.
"I listened to the ScienceMatters episode 6 podcast in my office during one of my lunch breaks," Chung says. "It's fun to learn about the diverse areas of research within our College."
The quiz question for episode 6 was: What is the type of brain injury where one knows how to perform an action but can't do it?
The correct answer is ideomotor apraxia.
Join the Quiz for Episode 7
Episode 7 features Carlos Silva and his research into the next generation of semiconductors for electronic devices.
Here’s the quiz question for episode 7:
What particle is made up of an electron and an electron hole?
Submit answer here by 5 PM on Monday, Nov 4.
Periodic table t-shirts, must-have beaker mugs, and textured posters perfect for dorm rooms are among the prizes for winners, who are picked at random from all submitting correct answers. Look for the challenge during each week’s new episode, dropping on Tuesdays from Sept. 17 to Nov. 19.
The 2019 Nobel Prize in Physiology or Medicine was awarded jointly to William G. Kaelin Jr., Sir Peter J. Ratcliffe, and Gregg L. Semenza “for their discoveries of how cells sense and adapt to oxygen availability.” Kaelin is a professor at Harvard Medical School. Ratcliffe is the director of clinical research at Francis Crick Institute in London. Semenza is a professor at the Johns Hopkins University School of Medicine.
Much of the life on Earth that we humans experience uses oxygen to convert food – carbohydrates, fats, and proteins – into energy to drive life’s processes. In complex, multicellular organisms, including humans, cells in various tissues and organs experience different levels of oxygen, says Amit Reddi, an assistant professor in the School of Chemistry. “As a consequence, every cell must have the ability to sense oxygen and adapt metabolism to changes in oxygen levels.”
Kaelin, Ratcliffe, and Semenza contributed to figuring out exactly how cells sense and respond to oxygen. “Their work has had profound implications for modern medicine, including understanding and treating various cancers, where cells may no longer synchronize energy metabolism to oxygen levels, as well as a number of vascular diseases, where oxygen transport is no longer efficient,” Reddi says. “I’m thrilled for the new Nobel laureates.”
Reddi was an NIH Ruth L. Kirchstein postdoctoral fellow at Johns Hopkins University where Semenza is a faculty member. He says he often found inspiration from Semenza's studies on oxygen sensing, which guided his thinking on new conceptual paradigms for how life copes with oxygen.
Part of Reddi’s research is related to how reactive oxygen species (ROS), which are all derived from oxygen, can themselves signal metabolic changes in cells. “Our work is focused on how certain ROS are made and how they can be used to signal changes in metabolism and physiology,” Reddi says. “Because all ROS originate from oxygen, we believe that another layer of oxygen sensing is through the production and sensing of certain ROS.”
The Nobel Prize winners discovered how cells adapt to changes in oxygen level, particularly in low-oxygen conditions, says Young Jang, an assistant professor in the School of Biological Sciences. “Their discoveries laid the foundation for our understanding of how cells generate energy, make new blood cells, and how cancer cells grow.”
Jang’s research on stem cell metabolism and aging is directly related to oxygen sensing. Normally, mitochondria – the powerhouse of the cell – uses oxygen to generate ATP, the cell’s fuel. But in aged cells, regulation of oxygen is altered and mitochondria generate ROS. Excess ROS production and oxidative damage to proteins, lipids, and DNA/RNA are key culprits that cause cellular aging, Jang says.
Briefly, Jang overlapped with Kaelin in Harvard. He recalls that Kaelin’s lab “was interested in knowing whether oxygen sensing and metabolic changes can be communicated from one organ to another. He wanted to use parabiosis to test his idea.” Parabiosis is the physical joining of two individuals enabling cells, tissues, and organs to communicate through blood. It is another research area for Jang.
“I am very happy for Dr. Kaelin and his cowinners,” Jang says.
The National Institutes of Health know a good investment when they see one, and they definitely see one in Joe Lachance, researcher in the Petit Institute for Bioengineering and Bioscience at the Georgia Institute of Technology. And to prove it, the NIH recently granted Lachance an R35 Maximizing Investigators’ Research Award (MIRA).
The grant, valued at $1.88 million over five years, will support Lachance’s research strategy, which includes the analysis of ancient and modern genomes, mathematical modeling, and the development of new bioinformatics tools.
Lachance, whose research bridges the gap between evolutionary genetics and genetic epidemiology, is motivated by several questions: How have hereditary disease risks evolved in the recent past? What sorts of genetic architectures are more likely to result in health inequities? How can genomic medicine be extended to people with different ancestries?
“We’ve taken an evolutionary perspective toward genetic medicine and global health,” says Lachance, assistant professor in the School of Biological Sciences, whose research is directly related to the NIH’s All of Us initiative.
The R35 MIRA program was designed to increase the stability of funding for NIGMS-supported investigators like Lachance, improving their ability to take on ambitious projects and take more creative approaches to biomedical problems.
“This grant, I think, demonstrates great confidence in our approach to the research,” Lachance said. “It enables us to devote more our time and energy on doing the actual science and developing the next generation of researchers.”
Corals create potions that fight bacterial attackers, but warming appears to tip the scales against the potions as they battle a bacterium common in coral bleaching, according to a new study. Reef conservation may offer hope: A particular potion, gathered from reefs protected against seaweed overgrowth, proved more robust.
The protected Pacific reefs were populated by diverse corals and shimmered with colorful fish, said researchers who snorkeled off of Fiji to collect samples for the study. Oceanic ecologists from the Georgia Institute of Technology compared coral potions from these reefs, where fishing was prohibited, with those from heavily fished reefs, where seaweed inundated corals because few fish were left to eat it.
The medicated solutions, or potions, may contain a multitude of chemicals, and the researchers did not analyze their makeup. This is a possible next step, but here the researchers simply wanted to establish if the potions offered any real defense against pathogens and how warming and overfishing might weaken it.
Conservation matters
“I thought I probably wouldn’t see antibiotic effects from these washes. I was surprised to see such strong effects, and I was surprised to see that reef protections made a difference,” said the study’s first author, Deanna Beatty.
“There is a lot of argument now about whether local management can help in the face of global stresses – whether what a Fijian village does matters when people in London and Los Angeles burn fossil fuels to drive to work,” said Mark Hay, the study’s principal investigator, Regents Professor and Harry and Linda Teasley Chair in Georgia Tech’s School of Biological Sciences.
“Our work indicates that local management provides a degree of insurance against global stresses, but there are likely higher temperatures that render the insurance ineffective.”
[Ready for graduate school? Here's how to apply to Georgia Tech.]
Adding heat
The researchers collected three coral species along with seawater surrounding each species at protected reefs and at overfished reefs. In their Georgia Tech lab, they tested their solutions against the pathogen Vibrio coralliilyticus at 24 degrees Celsius (75.2 Fahrenheit), an everyday Fijian water temperature, and at 28 degrees (82.4 F), common during ocean heating events.
“We chose Vibrio because it commonly infects corals, and it’s associated with coral bleaching in these warming events. It’s related to other bleaching pathogens and could serve as a model for them as well,” Hay said.
“We chose 24 C and 28 C because they’re representative of the variations you see on Fijian reefs these days. Those are temperatures where the bacteria are more benign or more virulent,” Beatty said.
The data showed that warming disadvantaged all potions against Vibrio and conservation aided a potion from a key coral species. The team, which included coauthor Kim Ritchie from the University of South Carolina Beaufort, published its study in the journal Science Advances on Oct. 2. The research was funded by the National Institutes of Health’s Fogarty International Center, the National Science Foundation, and the Simons Foundation.
Deeper dive into the experiment
Seaweed hedges
The unprotected reefs’ shabby appearance portended their effects on the one potion associated with a key coral species.
“When you swim out of the no-fishing area and into the overfished area, you hit a hedge of seaweed. You have about 4 to 16% corals and 50 to 90% seaweed there. On the protected reef, you have less than 3% seaweed and about 60% corals,” Hay said.
Hay has researched marine ecology for over four decades and has seen this before, when coral reefs died off closer to home.
“Thirty years ago, when Caribbean reefs were vanishing, I saw overfishing as a big deal there, when seaweed took over,” he said, adding that global warming has become an overriding factor. “In the Pacific, many reefs that were not overfished have been wiped out in warming events. It just got too hot for too long.”
Distilling potion
The potions are products of the corals and associated microbes, which comprise a biological team called a holobiont.
To arrive at potions focused on chemical effects, the researchers agitated the coral holobionts and ocean water then freeze-dried and irradiated the resulting liquid to destroy remnants of life that could have augmented chemical action. Some viruses may have withstood sterilization, but it would have weakened any effect they may have had, if there were any.
Then the researchers tested the potions on Vibrio.
“All of the solutions’ defenses were compromised to varying extents at elevated temperatures where we see corals getting sick in the ocean,” Hay said.
But reef protection benefited the potion taken from the species Acropora millepora.
“The beneficial effect in the solution tested in the lab was better when Acropora came from protected areas, and this difference became more pronounced at 28 degrees Celsius,” said Beatty, who finished her Ph.D. with Hay and is now a postdoctoral researcher at the University of California, Davis.
Acropora architecture
Of the three species with potions that were tested, Acropora millepora may be a special one.
It is part of a genus – larger taxonomic category – containing about 150 of the roughly 600 species in Pacific reefs, and Acropora are core builders of reef structures. They grow higher as sea level rises, helping maintain healthy positions for whole reefs.
“Acropora are big and branching and make lots of crevices where fish live. The evolution of lots of reef fish parallels the evolution of Acropora in particular,” Hay said.
If fish can hang on, they may buy Acropora more time, and coral reefs perhaps, too.
Also READ: When Coral Species Vanish, Their Absence Can Imperil Surviving Corals
These researchers coauthored the study: Deanna Beatty, Jinu Valayil, Cody Clements, and Frank Stewart of Georgia Tech. The research was funded by the National Institutes of Health (grant 2 U19 TW007401-10), the National Science Foundation (grant OCE 717 0929119), the Simons Foundation (grant 346253), and the Teasley Endowment. Any findings, conclusions, or recommendations are those of the authors and not necessarily of the sponsors. DOI: https://doi.org/10.1126/sciadv.aay1048
Writer & Media Representative: Ben Brumfield (404-272-2780), email: ben.brumfield@comm.gatech.edu
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The College of Sciences held its annual summer dinner on Sept. 18, hosted by Susan Lozier, the new dean and Betsy Middleton and John Clark Sutherland Chair of the College of Sciences. The gathering has become a tradition for welcoming new members; recognizing excellence in research, instruction, and service; and affirming the College’s special community of scholars.
Tim Cope, Christine Heitsch, and Marvin Whiteley received the 2019 Faculty Mentor Awards. Cope and Whiteley are professors in the School of Biological Sciences; Heitsch is a professor in the School of Mathematics.
Nominations for these awards come from early-career faculty. Nominators cite mentors’ willingness to make introductions, review proposals, and develop professional training programs as extremely helpful as they get familiar with and navigate their environment and roles.
"[Y]our recognition also shines a bright light on your school and the College of Sciences, for which we are grateful.”
Also celebrated at the 2019 Summer Dinner were recipients of distinguished faculty awards, funded through the generosity of alumni and friends.
Greg Blekherman, Martin Mourigal, and Ronghu Wu received the Cullen-Peck Fellowship Awards. These are made possible by a gift from alumni couple Frank Cullen and Libby Peck. The goal is to encourage the development of especially promising mid-career faculty. Bleckherman is an associate professor of mathematics, Mourigal is an assistant professor of physics, and Wu is an associate professor of chemistry and biochemistry.
Kim Cobb, professor of Earth and atmospheric sciences, received the 2019 Gretzinger Moving Forward Award. This is made possible by a gift from alumnus Ralph Gretzinger and his late wife, Jewel. The award recognizes leadership of a school chair or senior faculty member who has played a pivotal role in diversifying the composition of faculty, creating a family-friendly environment, and providing a supportive environment for early-career faculty.
Jennifer Glass, associate professor of Earth and atmospheric sciences, received the 2019 Eric R. Immel Memorial Award for Excellence in Teaching. This award is supported by an endowment fund given by alumnus Charles Crawford to recognize exemplary instruction of foundational courses.
“I am pleased that your distinction in research, teaching, and mentoring brings recognition your way,” Lozier said. “But your recognition also shines a bright light on your school and the College of Sciences, for which we are grateful.”
Lozier also welcomed faculty who joined in the 2019-20 academic year, herself included as professor of Earth and atmospheric sciences. Also present were Meghan Babcock and Keaton Fletcher, School of Psychology; Marcus Cicerone and Joshua Kretchmer, School of Chemistry and Biochemistry; and Glen Evenbly, School of Physics. Unable to attend were Alex Blumenthal, School of Mathematics, and Alonzo Whyte, School of Biological Sciences.
“As you set out on your academic journey, please know that we are here to support, mentor, and advise you along the way,” Lozier said. “Your good fortune will be ours as well.”
The Office of International Initiatives announces the launch of the Georgia Tech Guide for Responsible International Activities, a new online resource regarding guidelines, policies, and procedures around the Institute’s global activities and partnerships.
This summer, the Office of International Initiatives convened a working group of members of the Office of the Executive Vice President for Research and the Office of the Provost to develop a resource to guide educational and research activities that happen abroad. The major deliverables of the working group were designed to help Georgia Tech make decisions and ensure proper planning, compliance, and transparency around all international activities.
“Georgia Tech is proud to engage with researchers, scholars, and institutions all over the world as an expression of the Institute’s motto of Progress and Service,” said Chaouki T. Abdallah, Georgia Tech’s executive vice president for Research. “We remain wholeheartedly committed to those important global collaborations, but we must safeguard the Institute, and ensure all activities are fully transparent and in compliance with Georgia Tech policies, as well as applicable government laws and regulations.”
Site users can find direct links to Georgia Tech resources, policies, and relevant campus contacts for offices and units that manage a variety of issues, including export control; managing conflicts of interest; appointments at other institutions; intellectual property; materials, data, and confidential information; the Foreign Corrupt Practices Act (FCPA); international agreements; disclosing foreign relationships; lab tours; hosting foreign visitors; and international travel.
“Georgia Tech promotes a culture of global engagement and believes that our community is enriched through opportunities to study, work, serve, or do research abroad,” said Rafael L. Bras, provost and executive vice president for Academic Affairs. “Thanks to the working group, the guide now provides access to Tech’s standing policies and procedures governing international activities in one centralized location.”
The guide will be maintained by the Office of International Initiatives and will be available on faculty and staff resource pages at several touchpoints, including global.gatech.edu, research.gatech.edu, and provost.gatech.edu, among others.
The working group also refined Georgia Tech’s Guiding Principles for International Activities, a standard set of objective criteria used by the Office of International Initiatives for measuring each international activity’s impact on academic activities, value to the Institute, compliance with applicable policies, sustainability and viability, and risk assessment and mitigation concerns.
Georgia Tech is also in the process of creating an International Advisory Committee comprised of representatives of the administration, faculty, and staff. The committee will be chaired by Yves Berthelot, vice provost for International Initiatives, and will provide guidance and advice regarding how Georgia Tech engages internationally (e.g. research, MOUs, master research agreements, etc.).
“Our success in international activities must be assessed in full consideration of geopolitical factors, as well as current and potential state and federal regulations and legislation,” said Berthelot. “With those considerations in mind, the work of the committee will prove vital for Georgia Tech as we continue to grow our relationships across the world and explore new opportunities to engage globally.”
Nominations for the committee are currently being accepted through Oct. 7. Faculty and staff are encouraged to submit self-nominations or nominations for a colleague. Details on the final committee roster will be made available via the online tool, once finalized. To self-nominate or nominate a colleague for the committee, or for more information on the working group’s activities, contact Monique Tavares, director of Global Operations at mtavares@gatech.edu.
Editor's Note: This essay by Kimberly Chen and Matthew Herron was originally published in The Science Breaker on Sept. 10, 2019. It is reposted here with permission.
Discussions about the evolution of multicellularity tend to focus on animals and plants, but there have actually been at least 25 independent origins of multicellularity in the history of life on this planet, including fungi, slime molds, several groups of algae, cyanobacteria and myxobacteria. So how did early single cells evolve into organisms consisting of multiple cells, and why? What were the advantages of being a multicellular organism?
It would be helpful in answering these critical questions if we could study the fossil history of multicellular organisms. However, few fossils have been found that show the earliest stages of the transition to multicellular life. Most such transitions happened hundreds of millions or even billions of years ago, and fossils that old are very rare. So it is really hard to know just what happened that far back.
Since we couldn't learn much from fossils, we used experimental evolution to replay life's tape in the laboratory. One favored driver for the evolution of multicellularity is Predation. Because most predators can only consume prey up to a certain size, getting bigger can provide protection against being eaten, and one way for single-celled organisms to get bigger is to form multicellular structures.
We used single-celled, free-swimming green algae (Chlamydomonas reinhardtii) to explore the possible evolution of multicellularity. The predators we used in our experiment are filter-feeding ciliates (Paramecium tetraurelia). Despite being unicellular, these ciliates are larger and graze on small algae by sweeping them into their mouths with hairlike structures called cilia. We cultured some algae with predators and some without predators for a year to see if predators would increase the evolution of multicellularity.
Single-celled algae normally multiply by a process called multiple fission, where a cell goes through one to three divisions to produce two, four or eight daughter cells. These daughters then hatch out of the mother cell wall to start the cycle again. By the end of our experiment, some of the cultures grown with predators had become multicellular by modifying their cell life cycle. In these evolved multicellular algae, we did not observe the last hatching step when the cell cycle is about to complete.
Instead, we found that each daughter cell continued its cell cycle within the mother cell wall, leading to multicellular clusters. Strictly speaking, cells in each cluster are descendants of a mother cell, and are genetic clones of each other. As clusters continue to grow bigger, they reach a limit and start to release single cells or small clusters of cells. In a separate experiment, we further showed that it is the cluster formation rather than other prey defenses that protects cells from predation. Selective pressure through predators, therefore, can favor the increase of clusters over single cells.
The multicellular life cycle is genetically fixed in the evolved multicellular algae, continuing even when they are grown in normal growth conditions without predators. But there is a price to pay. In nature, single-celled algae use slim threadlike structures called flagella to swim towards the light they need for photosynthesis. However, in the evolved multicellular algae each cell's flagella, even though they are present and active, are trapped within the mother cell wall. As a result, the multicellular clusters do not show noticeable movement. Such a drawback can be mitigated in the laboratory, since we culture these algae in an incubator with an ample supply of light. They might not be so lucky in nature.
From this experiment, we learned that multicellularity evolves readily in response to predation. This initial transition, although being a key step towards more complex life, does not seem to require organisms like green algae to evolve something new. Rather, this can be accomplished through a small modification to the existing cell cycle. The multicellular algae that evolved in our experiment also provide opportunities for further evolution experiments. For example, will they be able to regain the ability to swim? Can they evolve a division of labor, with cells becoming specialized to perform different tasks as we see in more complex multicellular organisms? These questions are under our current investigations.
Kimberly Chen is a postdoctoral researcher and Matthew Herron is a senior research scientist in the School of Biological Sciences.
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