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Biology

Saket Navlakha

By Daniel Dunaief

Plants have to solve challenges in their environment – without a brain or the kind of mobility mammals rely on to survive – through strategies and computations that keep them alive and allow them to reproduce.

Intrigued by plants and by the neurobiology that affect decisions or behavior in a range of other organisms, Associate Professor Saket Navlakha recently joined Cold Spring Harbor Laboratory to study the processes a range of organisms use.

“Biological systems have to solve problems to survive,” said Navlakha. “The hope is that by studying these algorithms, we can inspire new methods for computer science and engineering and, at the same time, come up with new ways to predict and model behaviors of these systems.”

Navlakha, who has a doctorate in computer science from the University of Maryland College Park and conducted postdoctoral research at Carnegie Mellon University’s Machine Learning Department, focuses on the “algorithms of nature,” in which organisms evolved ways to solve problems that enhance the likelihood of their survival.

In his first three months at CSHL, Navlakha plans to do an interview tour, speaking with researchers who study cancer, molecular biology, neurology and plants.

While his primary areas of focus have been on plants and neurobiology, he appreciates that the internationally recognized research facility presents “new opportunities” for him and a lab in which he intends to hire four to six scientists over the next two years.

Adam Siepel, the chair of the Simons Center for Quantitative Biology and professor at the Watson School of Biological Sciences at Cold Spring Harbor Laboratory, led the recruitment of Navlakha.

In an email, Siepel wrote that Navlakha “immediately struck us as an ideal candidate for the center” in part because he is a “free thinker with an eye for interesting and important problems in biology.”

Navlakha believes processes and strategies that foster survival spring from a set of principles that helps them thrive and adapt. In 2018, when he was at the Salk Center for Integrative Biology, he wrote a piece for Wired magazine about species extinction. “By not preserving [species that become extinct], we are losing out on interesting ideas that evolution gave them to survive,” he said.

Even amid these losses, however, Navlakha recognizes the lessons computer scientists and engineers like him can learn. Through losses and failures, humans can understand the limitations of algorithms that only allowed a species to survive up to a point, as conditions pushed its algorithms past a tipping point.

At its core, Navlakha’s approach to these algorithms includes the idea that biological systems perform computations. He originally studied brains because they are “such an elegant computer, doing all kinds of things that modern, human-made computers can’t do,” he said.

When he was at the Salk Institute, he spoke with colleagues in plant biology who told him about research that examined how plants modify their shape amid a changing environment, which is what triggered his interest in plants.

One of the themes of his work involves understanding trade-offs. Doing well in one task typically means doing worse in another. He likened this analysis to investing in stocks. An investor can put considerable funds into one stock, like Apple, or diversify a portfolio, investing less money per stock in a variety of companies from different sectors.

“We’ve been studying how plants hedge” their bets, he said. The hedge in this description bears no relation to a collection of plants at the edge of a property.

A plant can create one huge seed that might survive a drought or other environmental threat, or it can diversify the types of seeds. “We’re really interested in understanding these trade-offs, how they hedge, and what kind of strategies” they employ, he said.

Ziv Bar-Joseph, a professor of computer science at Carnegie Mellon University who has known Navlakha for over eight years, suggested Navlakha has “deep insights.” 

In an email, Bar-Joseph described Navlakha’s biggest achievement as his work that shows how the brain uses a computational method to store and retrieve smells. 

“This work both solved an important mystery about how the brain functions and informed us on novel usages of an important computational method, thus contributing to both areas,” Bar-Joseph explained.

Navlakha doesn’t have a typical laboratory filled with beakers, pipettes or plants growing under various conditions. He relies on wet labs to provide data that he then interprets and analyzes as a part of the Simons Center for Quantitative Biology. While his training is in computer science, he has shown a talent for experimental research as well. 

Bar-Joseph recalled how Navlakha performed experiments and analysis. In a short time, Navlakha “was able to master very involved techniques and obtained very good results.” 

Navlakha explained that the work he does colors the way he sees the world. “People walk by plants without paying attention to the incredible computations that they’re doing to keep us on this planet,” he said. “Computation is the basis of life.”

A resident of Great Neck, Navlakha recently married Sejal Morjaria, an infectious disease physician at Sloan Kettering, who works with patients who have cancer. The couple met through an online dating app when he was in San Diego and she lived in New York. They chatted for a while without any expectation of seeing each other, until he traveled to Washington, D.C                                 for a conference.

Navlakha enjoys playing numerous sports, including tennis and basketball. He also played hockey. He and Morjaria participate in yoga classes together.

Navlakha, who grew up in Miami, Florida, said he had to readjust to life on Long Island after living in Southern California for several years. “San Diego makes you weak,” he joked.

In his work, Navlakha hopes to bring together two fields in a different way.

Given the importance of computations, Navlakha appreciates a corollary to the concept proposed by Rene Descartes’ “I think, therefore I am.” For Navlakha, “I compute, therefore I am” describes processes he studies among animals and plants.

By Elof Axel Carlson

Elof Axel Carlson

Science is a way of interpreting the universe in the era in which we live. One of the realities of our lives is that we do not know how much of the world we think we know is really incomplete.

Think of it this way — If you grew up when the American Revolutionary War was being fought, you would not know a lot. You would not know your body is composed of cells. You would not know that heredity is transmitted by genes located on chromosomes present in nuclei of cells because no one knew there were nuclei, chromosomes or genes.

You would also not know there are biochemical pathways that carry out your metabolism in cell organelles because no one then knew there was such a thing as metabolism, biochemical pathways or cell organelles. And you would not know that infectious diseases are associated with bacterial and viral infections nor would you know that your body is regulated by hormones. If you created a time line of scientific findings in the life sciences, the cell theory was introduced in 1838. Cells were named in 1665, but Robert Hooke thought they accounted for the buoyancy of cork bark. He drew them as empty boxes.

When Schleiden and Schwann described cells, they were filled with fluid; and Schwann thought nuclei were crystallizing baby cells being formed in a cell. The cell doctrine (all cells arise from pre-existing cells) did not come until Remak and Virchow presented evidence for it. Mitosis, or cell division, was not worked out until the late 1870s; and meiosis of reproductive cells (sperm and eggs) was not worked out until the 1990s.

Fertilization involving one sperm and one egg was first seen in 1876, while most cell organelles were worked out for their functions and structure after the invention of the electron microscope in the 1930s. There was no organic chemistry before Wöhler synthesized molecules like urea in 1823, and biochemical pathways were not worked out until the 1940s.

DNA was not known to be the chemical composition of genes until 1944, the structure of DNA was worked out in 1953, molecular biology was not named until 1938 and the germ theory was worked out in the 1870s and 1880s by Pasteur and by Koch, who both demonstrated bacteria specific for infectious diseases. Embryology was worked out in 1759 by Wolff, while hormones were first named and found in 1903 by Bayliss and Starling.

What the history of the life sciences reveals is how dependent science is on new tools to investigate life. Microscopes up to 30 power came from Hooke’s efforts in 1665. A better microscope by Leeuwenhoek distinguished living organisms (“animalcules”) at up to 500 power.

It was not until the 1830s that microscopes were able to overcome optical aberrations and not until the 1860s that a stain technology developed to see the contents of cells. This boosted observation to 2000 power. For the mid-20th century, cell fractionation made use of centrifuges and chromatography to separate organelles from their cells and work out their functions.

Experimental biology began in England with Harvey’s study in 1628 of the pumping action of the heart. Harvey was educated in Padua, Italy, where experimental science had been stressed by Galileo and his students who began applying it to the motion of the body relating bones and muscles to their functions. No one alive in 1750 (or earlier) could have predicted DNA, oxidative phosphorylation, the production of oxygen by plants, Mendel’s laws of heredity or the role of insulin in diabetes.

But what about the present? How complete is our knowledge of life processes? Are there major findings in the centuries to come that will make our present understanding look as quaint as reading the scientific literature in the 1700s?

We can describe what we would like to know based on our knowledge of the present and likely to be achievable. We cannot predict what may turn out to be new functions or structures in cells. At best (using what we do know) we can hope to create a synthetic cell that will be indistinguishable from the living cell from which it was chemically constructed. But that assumes the 300 or so genes in a synthetic cell will account for all the activities of the vague cytoplasm in which metabolism takes place.

For the level of viruses there are no such barriers and the polio virus has been synthesized artificially in cell-free test tubes in 2002 (an accomplishment of Eckard Wimmer at Stony Brook University).

Within a few years ongoing studies of bacteria and of yeast cells with artificial chromosomes, may resolve that question for the genome of a eukaryotic cell. I hope that an artificial cytoplasm will be worked out in that effort. That might be more of a challenge than presently assumed.

'A trip to the American Museum of Natural History was my idea of being in heaven.' - Elof Carlson

By Elof Axel Carlson

The life sciences are vast in the number of specialties that exist for those pursuing a career as a biologist. A majority of college biology majors are premedical or seek some sort of health-related field. As much as possible they hope the biology they learn will find its way into the health field they seek to enter. Persons who want to be scholars in biology are often motivated by a desire to know as much about life as they can. I was one of those from early childhood when a trip to the American Museum of Natural History was my idea of being in heaven.

Elof Axel Carlson

I loved learning about evolution and the diversity of life. I knew I wanted to be a geneticist when I was in ninth grade and learned about Paul Müller’s Nobel Prize work on inducing mutations. Like a duckling, I felt imprinted and wanted to work with Müller someday.

Graduate work was different. As a teaching assistant I got to see about 90 different specimens each week for the various organ systems displayed by students. Unlike the textbook perfect illustrations, veins and arteries could be slightly off in the specimens I looked at. Their colors differed. Their texture differed.

I also learned how much we didn’t know about life. For my specialty of genetics (with Müller, as I had hoped) I felt steeped in experimental design, techniques and ways of thinking. Doing a Ph.D. allowed me to examine a gene using the tools of X-raying to produce mutations of a particular gene and subtle genetic design to combine pieces of a gene — taking it apart and combining pieces that were slightly different. It gave me an insight into that gene (dumpy, in fruit flies) that for a short time (until I published my work) I was the only person in the world that knew its structure.

In my career I have taught biology for majors, biology for nonscience majors, genetics, human genetics and the history of genetics. I have taught lower division and upper division courses, graduate courses and first-year medical classes. I learned that sharing new knowledge with students excited their imaginations. I learned that the human disorders I discussed led to office visits; and if I didn’t know the information they sought, I went with them to the medical library and we looked up articles in the Index Medicus and discussed their significance.

Often that student was married and had a child with a birth defect (born without a thyroid, having a family trait that might appear like cystic fibrosis). I would prepare a genetic pedigree and give it to the student to stick in a family bible for future generations to read. I also delighted in going to meetings to discuss genetics with colleagues whose work I had read.

I was pleased that I shared a body plan with other mammals. I liked comparative anatomy, which taught me how other body plans work (mollusks, arthropods, worms, coelenterates, echinoderms). As a graduate student taking a vertebrate biology course, I went into a cave and plucked hibernating bats from a ceiling.

The world under a microscope is very different. To see amoebas, ciliated protozoans, rotifers and other organisms invisible to the naked eye or as mere dust-like specks is a thrill. I can go back in time and imagine myself as a toddler, a newborn, an embryo in my mother’s uterus or an implanting blastocyst rolling out of her fallopian tube. I can imagine myself as a zygote, beginning my journey as a one-celled potential organism typing this article into a computer. I can go back in time to my prehistoric ancestors and trace my evolution back to the first cellular organism (bacteria-like) more than 3 billion years ago.

I learned, too, that I contain multitudes of ancestors who gave me one or more of their genes for the 20,000 I got from my father’s sperm and the matching 20,000 genes in my mother’s egg nucleus. I contain some 37 trillion (that is, 37,000,000,000,000) cells or 2 to the 45th power, which means some 45 mitotic cell divisions since I was a zygote. I know that the warmth of my body is largely a product of the mitochondrial organelles in my cells that using the oxygen from the air I breathe and converting small molecules of digested food to provide energy that runs the metabolism of my body and disposes carbon dioxide that eventually is expelled from my lungs. This knowledge makes me aware of my vulnerability at the cellular level, the chromosome level and the genetic level of my DNA to the agents around me that can lead to birth defects cancers, and a premature aging.

Knowing my biology allows me to know my risks as well as new ways to celebrate my life.

Elof Axel Carlson is a distinguished teaching professor emeritus in the Department of Biochemistry and Cell Biology at Stony Brook University.

Mount Sinai Ocean Sciences Bowl team co-advisers David Chase and Glynis Nau-Ritter with members, Ariele Mule, Ben May, Claire Dana and Jonathan Yu. Photo from Glynis Nau-Ritter

Mount Sinai High School’s Ocean Sciences Bowl team is going national.

The group recently went head-to-head at Stony Brook University against 16 other teams throughout the state, and won first place at the regional Bay Scallop Bowl, an academic competition testing the students’ knowledge of marine sciences, including biology, chemistry, physics and geology. Mount Sinai’s 28-27 win against Great Neck South High School clinched its spot in the National Ocean Sciences Bowl, where they’ll join 25 teams from across the country in Corvallis, Oregon from April 20 to 23.

“Going in, we were skeptical, but once we started going through the day, our confidence really built up and everybody got to shine.”

—Ben May

On Feb. 18, the school’s four-student “A” team — senior Ben May, junior Jonathan Yu, sophomore Claire Dana, and freshman Ariele Mule — was one of two left standing after competing in a series of 10 fast-paced, undefeated buzzer, with the next determining the winner. With three seconds left on the clock, Great Neck South ran out of time on a bonus question that would’ve made it the winner, and Mount Sinai came out victorious. The high school has now placed first in 10 of the 16 annual Bay Scallop Bowls.

“It was probably the most exciting competition we’ve had in the Ocean Bowl,” said team co-advisor Glynis Nau-Ritter, a science teacher at the high school. “We work them hard and it pays off.”

Co-advisor David Chase echoed Nau-Ritter’s excitement.

“The students here have not only won the competition, but they’ve expanded their knowledge,” he said. “I’m very proud to be able to contribute to their success, and it’s great to be working with the best of the best.”

May, the team’s captain, said he and his teammates experienced “the ultimate coming-from-behind story” after going through a reconstruction year. May was the only returning member of the “A” team from last year, as the others had all graduated.

“It was thrilling to win and have the experience with so many people who share my love of the ocean.”

—Claire Dana

“Going in, we were skeptical, but once we started going through the day, our confidence really built up and everybody got to shine,” May said. “It was the closest competition I’ve ever been part of. We had no control over it. The other team captain and I were very friendly and it was a bonding experience. The stress of it really pulled us together.”

Calling nationals “a nerd’s dream,” May expressed pride for each of his teammates and said to prepare for the nationals, they met to study over winter break and will be meeting several days a week leading up to the nationwide competition.

“It was thrilling to win and have the experience with so many people who share my love of the ocean,” Dana said. “It was a great surprise, and I thought we all found pride in each other. We were all super ecstatic.”

In addition to competing in the nationals and receiving an all-expenses paid trip to Oregon, each of the four Mount Sinai students received a check for $400 for their victory.

The highest the Mount Sinai team has placed is fourth at nationals. If the students place in the top three or four teams, there are other monetary awards, as well as a trophy and possible student accessories like a netbook. The team could also potentially win a field trip to various research stations, like the Caribbean or West Coast.

A recently released quail sits on a log at Caleb Smith State Park Preserve in Smithtown. Photo by Talia Amorosano

By Talia Amorosano

A record number of bobwhite quails were released this year, and many of the students, teachers and parents who raised the birds helped welcome them to Caleb Smith State Park Preserve in Smithtown on Saturday.

For 12 years, Eric Powers, a biologist and wildlife educator, has been at the forefront of organizing the annual quail release at Caleb Smith and other parks in the area. He described this year’s event as the largest one yet, as a record number of schools raised the quail chicks and 1,400 quails were released.

“The idea of bringing back the quail is to bring balance back to our ecosystem,” Powers said at the rainy morning release.

Unlike nonnative guinea fowl, which “eat good wildlife” like salamanders and dragonflies, northern bobwhite quail are native to Long Island and play a vital role in controlling tick populations without harming other native species, according to Powers.

Children and parents watch quail being released. Photo by Talia Amorosano
Children and parents watch quail being released. Photo by Talia Amorosano

Those in attendance included volunteers, students, teachers and Long Island comedian Joey Kola, who said that he “saw this program and jumped on right away” after personally experiencing Rocky Mountain spotted fever, a tick-borne illness transmitted to humans through a tick bite.

Attendees initially gathered inside the park’s nature museum, where they learned about the quail, viewed preserved eggs and touched feather samples before listening to Powers’ talk.

“What we see is we get this immediate clearing of ticks [after the quail are released],” Powers said, but “cats are outright hammering these birds.”

Powers described indoor-outdoor cats as the biggest threat to quail upon their release, and suggested people make use of what he referred to as “catios” — enclosed patios where cats can get outside without hunting native animals.

However, because this is the first year the Caleb Smith quail cage has reached overcapacity — forcing a few hundred quail to be released earlier — Powers is optimistic the quail population may begin to take hold on its own if school and community participation continues to increase.

Kids and adults alike were certainly enthusiastic about the release, as they gathered in the pouring rain to watch 500 birds abandon their cage and taste freedom for the first time. The quail were tentative at first, but as soon as one group took flight others ran through the crowd and into the woods. The remaining quail were released later on in the day.

A few observers got a truly interactive experience when frantic quail landed on their umbrellas and even perched on their arms. And after the initial release, teachers and students took boxes of quail to various locations around the park and carried out their own private releases.

Only time will tell how many of the birds will survive in the wild, but with increased community awareness that quail have the potential to lower the population of disease-ridden ticks, and a better understanding of the dangers posed to quail by cats, it seems likely that the birds most recently released will have a better chance of survival than those released in the past.