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Food for thought

Solving the climate crisis may start with what’s on your plate

By 2023, 8 billion people are expected to be living on Earth, and we’ll all be facing a serious challenge: how to feed everyone. We spoke with some of the experts at Tel Aviv University about how our choice of what to put on our plates can affect the rainforests on the other end of the globe.

Humanity in crisis

The idea of food security is that every person has the right to receive and obtain enough food to sustain them in good health over time. But even today, our planet is already struggling to keep up with demand, and we keep hearing reports of damage and depletion of basic resources like fresh water, usable territory, and energy. So how will we feed 9 billion people, a decade from now? “The food security crisis is considered a global problem,” explains Prof. Nir Ohad, head of the Manna Center for Food Safety and Security at Tel Aviv University. “In many parts of the world, the three basic conditions for food security do not exist: availability, production and accessibility. We’ve also had periods of austerity in Israel, where store shelves were empty and products were rationed. Today, thankfully, the situation is different, but take a country like Venezuela, which is rich in resources, but today is facing an economic collapse and suffering from severe problems related to food.”

What causes a crisis of this magnitude? According to Dr. Hagit Ulanovsky, from the Porter School of Environmental Studies, an expert on environmental and health risk management and one of the founders of the Israeli Forum for Sustainable Nutrition, there are many reasons: “Efficient agriculture requires environmental resources: soil, water, sunlight, fertilizer and more. But it doesn’t end there. The food production process doesn’t stop there, there’s also transporting the food and marketing it, which requires many additional resources. All of this adversely affects the environment: destroying the rainforests, soil erosion, pollution of the environment with excess fertilizers and pesticides, using up a lot of water, and greenhouse gas emissions in significant quantities, just like the industrial, transport or energy sectors.”

Recently, the headlines were dominated by huge fires in the Amazon rainforests, considered the “green lung of the Earth,” caused largely by the world’s growing demand for meat. Extensive forest areas were destroyed to make room for cattle. “The environmental cost of raising animals for food is huge,” explains Dr. Ulanovsky. What’s even more sad is that it’s not worthwhile. The high environmental cost is due to low ‘conversion efficiency’. For example: for every 100 calories the chicken eats, we will get about 15 calories in the egg it lays. For every 100 calories a cow eats, we only get about 3 calories! Where did the rest of the energy go? To sustain the life processes of a cow: breathing, digestion, movement, etc. Conversely, if we grow on the same soil and with the same amount of water food that is suitable for humans instead of animal feed – then we can eat 100 calories of that food and… actually get 100 calories.”

Stop now, before it runs out. The process of burning rainforest for the benefit of raising cattle.

Stop now, before it runs out. The process of burning rainforest for the benefit of raising cattle. 

Dr. Ulanovsky continues: “In light of increasing climate change, and in response to the worsening environmental pollution worldwide and especially in Israel, concerns about food insecurity are rising not only at the individual level, but also at the national level: extreme weather events will damage agricultural produce, soil and water. Pollution will seep into the vegetables we eat, new plant diseases will attack the fields and orchards. Disaster on the other side of the world will greatly affect our food security here, because most of the food we eat is imported from overseas, and therefore a reduction in production in Argentina or Ukraine will not only raise prices but may prevent food exports to Israel,” she concludes.

This is how the vicious cycle works: meat consumption in Israel is driving demand, which is accelerating the process of growing and production in distant countries like Argentina and Australia, and the environmental cost of the meat industry is rising. So how do we get out of the loop? One of the solutions offered by Prof. Ohad and Dr. Ulanovsky in their courses at Tel Aviv University is a shift to a sustainable diet.

 There's not enough for everyone. Empty food bowls in areas in a country in crisis.

 There’s not enough for everyone. Empty food bowls in areas in a country in crisis. 

The solution: less meat

The first thing people can do is make smart dietary choices. “Each of us has the ability to make a positive impact on the Israeli and even the global food system,” explains Dr. Ulanovsky. “We need to do all we can to preserve environmental resources, to enable continued healthy food production. This is especially important in the dense and small state of Israel, where the birth rate is particularly high. Israel is recognized worldwide as the startup nation, but not everyone knows that it is also the world leader in the most up-to-date nutrition guidelines, both health-wise and environmentally.”

Dr. Ulanovsky’s recommendation is to start with a simple step – to choose what to put in the kitchen and the dish you’re making. “This choice has a lot of power and the ability to make a difference. The new nutrition guidelines issued by the Ministry of Health in Israel include health considerations, and also present the environmental aspects of our dietary choices,” she says.

It turns out that health and environmental protection are overlapping concerns when it comes to culinary choices. “There are different approaches to determining a healthy diet, and the most well-tailored for our region is the Mediterranean diet, recommended by the Ministry of Health, where you eat lots of fruits and vegetables and add dairy and meat products in a balanced way,” Prof. Ohad says. “Vegetarian and vegan diets, which maintain the same nutritional balance of meat, dairy and egg substitutes, also help maintain a healthy lifestyle, sustainable agriculture and the environment. These diets are taking up ever-increasing space, which is a good thing.”

A healthy diet that also helps the environment - a diet rich in vegetables, fruits and legumes

A healthy diet that also helps the environment – a diet rich in vegetables, fruits and legumes

“Veganism is the best diet for the environment, and it is suitable and healthy for most people, although it is recommended to get professional nutritional advice in the process of transitioning to it,” Dr. Ulanovsky explains, adding, “However, many people find it difficult to give up animal products, and not everyone can make the change. But if each of us starts small and makes a gradual change, together we can make a difference to our planet.”

TAU grad’s short film sold to HBO

Atara Frish’s “The Love Letter”, produced at the Steve Tisch School of Film and Television, was purchased for broadcast by HBO Europe.

“The Love Letter” is a 19-minute-long film that deals with a complex relationship between two female soldiers in the Israel Defense Forces, a novice soldier and her direct superior. The relationship between the two ranges from romantic attraction to standard military bureaucracy. Noa (Gili Beit Hallahmi), a dedicated commander of new recruits in the IDF, receives a mysterious love letter from one of her female underlings. Suspecting that the letter is fake, she’s forced to choose between adhering to strict military protocol and giving in to her desire to feel loved, if only for a moment.

The film had its world premiere at the Tribeca Festival’s Short Film Competition, where it received special notice in the “Student Vision” category. The film also won the top prize at the Jerusalem Festival’s Short Film Competition, and was screened at Palm Springs Festival in the U.S. and many other international film festivals around the world.

“The Love Letter” was produced as part of the “Heroine” project, where five female directors created a short film each, which was then combined into one full-length feature. The project was produced at the Steve Tisch School of Film and Television, under the artistic direction of Michal Winnick and Mia Dreyfus, and produced by Efrat Cohen (Gaudamus Productions), and screened around the world.

Atara Frish is currently working on a TV series based on “The Love Letter”, as well as writing a full-length script for a feature film.

Mmm Mmm Marrow?

Study Finds Prehistoric Humans Ate Bone Marrow Like Canned Soup 400,000 Years Ago

Bone and skin preserved the nutritious marrow for later consumption, TAU researchers say Tel Aviv University researchers, in collaboration with scholars from Spain, have uncovered evidence of the storage and delayed consumption of animal bone marrow at Qesem Cave near Tel Aviv, the site of many major discoveries from the late Lower Paleolithic period some 400,000 years ago. The research provides direct evidence that early Paleolithic people saved animal bones for up to nine weeks before feasting on them inside Qesem Cave. The study, which was published in the October 9 issue of Science Advances, was led by Dr. Ruth Blasco of TAU’s Department of Archaeology and Ancient Near Eastern Civilizations and Centro Nacional de Investigación Sobre la Evolución Humana (CENIEH) and her TAU colleagues Prof. Ran Barkai and Prof. Avi Gopher. It was conducted in collaboration with Profs. Jordi Rosell and Maite Arilla of Universitat Rovira i Virgili (URV) and Institut Català de Paleoecologia Humana i Evolució Social (IPHES); Prof. Antoni Margalida of University of Lleida, University of Bern, and the Institute for Game and Wildlife Research (IREC); and Prof. Daniel Villalba of University of Lleida. “Bone marrow constitutes a significant source of nutrition and as such was long featured in the prehistoric diet,” explains Prof. Barkai. “Until now, evidence has pointed to immediate consumption of marrow following the procurement and removal of soft tissues. In our paper, we present evidence of storage and delayed consumption of bone marrow at Qesem Cave.” “This is the earliest evidence of such behavior and offers insight into the socioeconomics of the humans who lived at Qesem,” adds Dr. Blasco. “It also marks a threshold for new modes of Paleolithic human adaptation.” “Prehistoric humans brought to the cave selected body parts of the hunted animal carcasses,” explains Prof. Rosell. “The most common prey was fallow deer, and limbs and skulls were brought to the cave while the rest of the carcass was stripped of meat and fat at the hunting scene and left there. We found that the deer leg bones, specifically the metapodials, exhibited unique chopping marks on the shafts, which are not characteristic of the marks left from stripping fresh skin to fracture the bone and extract the marrow.” The researchers contend that the deer metapodials were kept at the cave covered in skin to facilitate the preservation of marrow for consumption in time of need. The researchers evaluated the preservation of bone marrow using an experimental series on deer, controlling exposure time and environmental parameters, combined with chemical analyses. The combination of archaeological and experimental results allowed them to isolate the specific marks linked to dry skin removal and determine a low rate of marrow fat degradation of up to nine weeks of exposure. “We discovered that preserving the bone along with the skin, for a period that could last for many weeks, enabled early humans to break the bone when necessary and eat the still nutritious bone marrow,” adds Dr. Blasco. “The bones were used as ‘cans’ that preserved the bone marrow for a long period until it was time to take off the dry skin, shatter the bone and eat the marrow,” Prof. Barkai emphasizes. Until recently, it was believed that the Paleolithic people were hunter gatherers who lived hand-to-mouth (the Stone Age version of farm-to-table), consuming whatever they caught that day and enduring long periods of hunger when food sources were scarce. “We show for the first time in our study that 420,000 to 200,000 years ago, prehistoric humans at Qesem Cave were sophisticated enough, intelligent enough and talented enough to know that it was possible to preserve particular bones of animals under specific conditions, and, when necessary, remove the skin, crack the bone and eat the bone marrow,” Prof. Gopher explains. According to the research, this is the earliest evidence in the world of food preservation and delayed consumption of food. This discovery joins other evidence of innovative behaviors found in Qesem Cave including recycling, the regular use of fire, and cooking and roasting meat. “We assume that all this was because elephants, previously a major source of food for humans, were no longer available, so the prehistoric humans in our region had to develop and invent new ways of living,” concludes Prof. Barkai. “This kind of behavior allowed humans to evolve and enter into a far more sophisticated kind of socioeconomic existence.” Photo caption: Marrow inside a metapodial bone after six weeks of storage. Credit: Dr. Ruth Blasco.  

TAU researchers develop new treatment for rare genetic disorder

Adolescents and young adults with familial adenomatous polyposis bear a high risk of developing cancer

Researchers from Tel Aviv University and Tel Aviv Sourasky Medical Center (Ichilov Hospital) have developed an innovative drug treatment for familial adenomatous polyposis (FAP), a rare, inherited condition that affects adolescents and young adults and often leads to colorectal cancer. The novel drug, based on antibiotics, inhibits the development of intestinal polyps that, left untreated, become cancerous. In a preliminary clinical trial, the condition of seven out of eight patients who completed the full treatment improved dramatically. The research was jointly led by Prof. Rina Rosin-Arbesfeld of the Department of Microbiology and Clinical Immunology at TAU’s Sackler School of Medicine and Prof. Revital Kariv of the Sackler School and the Department of Gastroenterology at Tel Aviv Sourasky Medical Center. FAP, which is characterized by multiple polyps along the gastrointestinal tract, especially in the large bowel, is caused by a mutation in the adenomatous polyposis coli (APC) gene. These mutations are also crucial for colorectal cancer development.

Why does FAP lead to colon cancer?

“To prevent the development of colorectal cancer, FAP patients are closely monitored via frequent colonoscopies to locate and remove their polyps,” Prof. Rosin-Arbesfeld says. “However, some patients must have their colons removed at a very young age, which dramatically affects their quality of life.” In its normal state, APC promotes the production of a protein that inhibits cancer development. But mutations to the APC gene produce an inactive protein that is unable to prevent the development of the polyps. In some FAP patients, the mutations in the APC gene are what are called “nonsense mutations.” “Each sequence of three nucleotides in the DNA is a code that tells the cell to produce a certain amino acid, which are the building blocks of the proteins produced in the body’s cells,” Prof. Rosin-Arbesfeld explains. “At the end of the protein coding sequence, there is usually a ‘stop codon’ to stop the protein production. But in FAP patients with a nonsense mutation, the APC’s stop codon appears prematurely, so the protein production stops prematurely, creating an inactive protein.”

Preventing surgical intervention

Previous experiments on cell cultures and mouse models in Prof. Rosin-Arbesfeld’s laboratory revealed that certain types of antibiotics caused cells to “ignore” the mutation stop codon and a normal protein resulted. These trials yielded promising results that led to the clinical trial at Tel Aviv Sourasky Medical Center. “Since the relevant antibiotics were already approved for human use, we decided to move directly from the laboratory to the clinic and to examine the treatment of FAP patients,” says Prof. Rosin-Arbesfeld. In the clinical study carried out by Prof. Kariv and Dr. Shlomi Cohen, director of the Pediatric Gastroenterology Unit at Dana-Dwek Children’s Hospital, 10 FAP patients received the novel antibiotic therapy. Eight of them completed the treatment, which lasted four months. Colonoscopies performed during and after the treatment showed that in seven patients the polyps significantly decreased in number. Moreover, the positive effects of the treatment were evident a year after it began. “Our goal as therapists, in addition to preventing cancer, is to improve the quality of life of our patients and their families and to enable them to live as full and normal lives as possible,” Prof. Kariv concludes. “The new therapeutic approach we are developing may allow patients to delay surgical intervention or even prevent it entirely.” The researchers recently won Tel Aviv University’s SPARK grant, which supports the development of applied research.

A better way to kill tumor cells

Engineered cells may be harnessed in new immunotherapy for cancer patients, Tel Aviv University researchers say

There is now a multitude of therapies to treat cancer, from chemotherapy and radiation to immunotherapy and small molecule inhibitors. Chemotherapy is still the most widely used cancer treatment, but chemotherapy attacks all the rapidly dividing cells that it locates within the body, whether they’re ultimately harmful or beneficial. A new Tel Aviv University study led by Dr. Yaron Carmi of TAU’s Sackler Faculty of Medicine finds that a form of immunotherapy used to treat the blood cancer leukemia may be effective in treating other kinds of cancer as well. A form of leukemic immunotherapy known as chimeric antigen receptors (CAR) T-cell therapy may also be effective in killing solid tumor cells coated in specific antibodies, the researchers say. The study was published in the Journal of Clinical Investigation on August 26.

Using the body’s own immune system

“Chemotherapy damages all fast-growing cells, including hair follicles and cells that line the gastrointestinal tract, and this attack on healthy cells causes serious side effects, which include hair loss, nausea, mood changes, pain, anaemia, nerve and muscle problems, and kidney issues,” explains Dr. Carmi. “Immunotherapy, on the other hand, is a type of biological therapy that uses the body’s own immune system to seek out and destroy cancer cells. Engineered T cells have been proven very successful in treating blood cancer but attempts to use them to fight solid cancers have been disappointing. “Our engineered cells have now shown efficacy in attacking solid tumors as well,” Dr. Carmi says. CAR T-cell therapy is a form of immunotherapy that uses altered T cells to fight cancer. T cells are a type of lymphocyte, or white blood cell, that plays a central role in the immune response. T cells are collected from the patient and modified in the lab to produce structures called CARs on their surface. These receptors allow the T cells to attach to a specific antigen on the tumor cells and kill them.

Fewer side effects, more precision

Side effects from immunotherapy may include severe inflammation, caused by an overactive immune system working to fight tumor cells. “Patients who utilize CAR T-cell therapy experience significantly fewer side effects than with chemotherapy,” adds Dr. Carmi. “And while chemotherapy is only effective while the drug is in the body, immunotherapy provides long-lasting protection against cancer. “Our lab discovered a distinct subset of helper T cells, also known as CD4+ T cells, that express the high-affinity receptor for IgG – an antibody – and efficiently kill tumor cells coated with these antibodies,” explains Dr. Carmi. “This method uses CAR T-cell therapy and combines it with antibody specificity. Based on this discovery we were able to engineer novel T cells with enhanced tumor-killing activity and higher specificity, compared with other T cell-based therapies for cancer. “Our engineered cells have the potential to overcome barriers usually faced by CAR T-cell therapy and have shown efficacy in solid tumors. This finding has the capability to change the way cancer is treated, demonstrating that the immune system can be utilized to identify and fight all types of cancer.”

TAU launches new center for quantum science & tech

The center will bring together twenty labs from across campus and offer academic programs as well as promote international ties

Tel Aviv University is proud to launch a new Center for Quantum Science and Technology, announced during the research workshop “From Quantum Computing to Quantum Chemistry.”
According to Tel Aviv University Rector, Prof. Yaron Oz: “The quantum revolution is knocking on our door, and many people expect it to be just as great and significant as the industrial and digital revolutions, completely transforming our technology and way of life,”
Prof. Oz also added that “Quantum theory, first developed more than a century ago, deals with phenomena at the level of tiny particles such as electrons and photons. Many quantum phenomena contradict human intuition and our experience in day to day reality.
“Leading TAU scientists, like Prof. Yakir Aharonov, have contributed significantly to our understanding of these phenomena. Applied quantum research is a relatively new field that is rapidly gaining momentum both in Israel and worldwide, and this is the right time to put considerable effort into it.”

Twenty labs from different disciplines

The new Center for Quantum Science and Technology is expected to bring together about twenty research labs from different faculties across campus, from a diverse array of scientific disciplines.
The Center will combine three main purposes: academic programs in relevant tracks such as quantum computing and quantum communication, designed to attract the best young minds to this innovative field, research activities based on TAU’s multidisciplinary nature, enabling collaborations between researchers from many different disciplines: computing, materials, sensors, chemistry, physics and mathematics, and later also economics, business and more.
It will also work forming international ties with research centers and business corporations – including giants like Google, IBM and Microsoft, who are developing quantum technologies, alongside potential consumers (like the financial sector), who must prepare for the advent of quantum computing.
The Center will also recruit new faculty members, organize conferences and workshops, and offer scholarships and fellowships for students.

TAU launches new center for quantum science & tech

The center will bring together twenty labs from across campus and offer academic programs as well as promote international ties

Tel Aviv University is proud to launch a new Center for Quantum Science and Technology, announced during the research workshop “From Quantum Computing to Quantum Chemistry.”
According to Tel Aviv University Rector, Prof. Yaron Oz: “The quantum revolution is knocking on our door, and many people expect it to be just as great and significant as the industrial and digital revolutions, completely transforming our technology and way of life,”
Prof. Oz also added that “Quantum theory, first developed more than a century ago, deals with phenomena at the level of tiny particles such as electrons and photons. Many quantum phenomena contradict human intuition and our experience in day to day reality.
“Leading TAU scientists, like Prof. Yakir Aharonov, have contributed significantly to our understanding of these phenomena. Applied quantum research is a relatively new field that is rapidly gaining momentum both in Israel and worldwide, and this is the right time to put considerable effort into it.”

Twenty labs from different disciplines

The new Center for Quantum Science and Technology is expected to bring together about twenty research labs from different faculties across campus, from a diverse array of scientific disciplines.
The Center will combine three main purposes: academic programs in relevant tracks such as quantum computing and quantum communication, designed to attract the best young minds to this innovative field, research activities based on TAU’s multidisciplinary nature, enabling collaborations between researchers from many different disciplines: computing, materials, sensors, chemistry, physics and mathematics, and later also economics, business and more.
It will also work forming international ties with research centers and business corporations – including giants like Google, IBM and Microsoft, who are developing quantum technologies, alongside potential consumers (like the financial sector), who must prepare for the advent of quantum computing.
The Center will also recruit new faculty members, organize conferences and workshops, and offer scholarships and fellowships for students.

TAU Alumni lead The Marker’s 40 Under 40 list

The Marker magazine has published its list of 40 most influential people under 40 in Israel for 2019, and the TAU Alumni community has 12 entries – more than any other university!

Our 12 influencers are:

  • Ayelet Perlstein, Counselor for Israel in the IDB Invest at Inter-American Development Bank, alumna of the Coller School of Management
  • Areen Safady Atila, Attorney at the Israeli State Attorney’s High Court department, alumna of the Faculty of Law
  • Dr. Nadav Levy, Director of the public transportation department at the Tel Aviv-Jaffa Municipality, alumnus of the Porter School of Environmental Studies
  • Sapir Caduri, Software Engineer at Google Israel, alumna of the Blavatnik School of Computer Science
  • Roni Bonjack, Head of Developer Programs – Europe, Middle East and Africa at Facebook, alumna of the faculty of Engineering
  • Dr. Shiri Chechik, Alumna and Researcher at the Blavatnik School of Computer Science
  • Leor Roseman, Researcher at the Imperial College London’s Centre for Psychedelic Research, Alumnus of the Faculty of Life Sciences and the School of Psychology
  • Yael Kochman, Partner & CEO at Re:Tech Innovation Hub, Alumna of the Faculty of Scocial Sciences & Coller School of Management
  • Miki Strasburger, VP Commerce & Aviation at EL AL Israel Airlines, Alumnus of the Coller School of Management
  • Sagi Ben Simon, Founding Partner at Beta Finance, Alumnus of the Faculty of Scocial Sciences & Coller School of Management
  • Imri Galai, General Manager at Wolt Israel, Alumnus of the Coller School of Management
  • Hisham Abdulhalim, Product Manager at PayPal, Masters Degree Student at the Faculty of Humanities

 

Each is a source of pride and honor for TAU!

The full project (in Hebrew)>

 

TAU among top 10 universities for venture capital-backed entrepreneurs

Joining Stanford, UC Berkeley, and MIT, TAU is the only non-U.S. university to make top 10 of global VC list

Tel Aviv University has been ranked eighth in the master list of 50 global universities producing the most venture capital-backed entrepreneurs, according to the 2019 PitchBook Universities Report. The top seven universities were all American, led by Stanford University and the University of California, Berkeley.

TAU appears on the list for the sixth year in a row, powerfully reflecting the university’s continuing success in the global business/investor community. TAU came in ahead of Yale University (ranked at #11), University of California, Los Angeles (#12), and Princeton University (#13). Three other Israeli universities made the PitchBook cut: The Technion-Israel Institute of Technology (#14), The Hebrew University of Jerusalem (#34), and Ben-Gurion University of the Negev (#49).

According to PitchBook, 694 TAU graduates-turned-entrepreneurs founded 577 companies raising $10.6 billion in a first round of venture funding in the period between January 2006 and August 2019. TAU was also ranked 13th in the list of the 25 top MBA programs, which was led by Harvard University.

At the center of innovation

TAU is Israel’s largest and most diverse university, consistently rated among the top 100 research universities globally. Located in the heart of Tel Aviv, the second largest technology sector in the world, TAU is the innovation hub of the “Start Up Nation.” With over half the 30,000+ student body engaged in multi-disciplinary research, TAU is uniquely positioned as an incubator of groundbreaking ideas.

As a venture capital data provider, PitchBook is recognized for its exhaustive data platform, which includes information on tens of thousands of VC-backed companies, investors, and service providers. PitchBook‘s database taps into the educational backgrounds of over thousands of VC founders worldwide.

The list ranks the top 50 universities that produced VC-backed founders on a global basis and is based on the number of founders that received first-round venture funding between January 1, 2006, and August 15, 2019.

Coral danger: breakdown in spawning could mean extinction

Synchronized coral spawning has become erratic, endangering the long-term survival of coral species, Tel Aviv University researchers say

Coral reefs are among the most diverse and productive ecosystems on our planet. But due to climate change and other human stressors, reef-building corals that reproduce by means of broadcast-spawning — the simultaneous release of eggs and sperm into open water — may now be under threat of extinction.

A new Tel Aviv University study finds that the highly synchronized, iconic spawning events of certain reef-building corals in the Gulf of Eilat/Aqaba, Red Sea, have completely changed over time and lost their vital synchrony, dramatically reducing chances of successful fertilization.

According to the research, led by Prof. Yossi Loya and PhD candidate Tom Shlesinger of TAU’s School of Zoology and published in Science, the breakdown in coral spawning synchrony has led to a dearth of new recruits and stagnant aging populations, creating circumstances for extinction.

It’s all in the timing

“Coral spawning, often described as ‘the greatest orgy in the world,’ is one of the greatest examples of synchronized phenomena in nature,” explains Prof. Loya. “Once a year, thousands of corals along hundreds of kilometers of a coral reef release their eggs and sperm simultaneously into the open water, where fertilization will later take place. Since both the eggs and the sperm of corals can persist only a few hours in the water, the timing of this event is critical.”

Successful fertilization, which can take place only within this narrow time window, has led to the evolution of a precise spawning synchrony. Such synchronicity relies on environmental cues: sea temperature, solar irradiance, wind, the phase of the moon and the time of sunset.

In 2015, the researchers initiated a long-term monitoring of coral spawning in the Gulf of Eilat/Aqaba. Over four years, they performed 225 night field surveys lasting three to six hours each during the annual coral reproductive season from June to September and recorded the number of spawning individuals of each coral species.

“We found that, in some of the most abundant coral species, the spawning synchrony had become erratic, contrasting both the widely accepted paradigm of highly synchronous coral spawning and studies performed on the exact same reefs decades ago,” says Shlesinger.

Extinction through reproductive failure

The researchers then investigated whether this breakdown in spawning synchrony translated into reproductive failure. They mapped thousands of corals within permanent reef plots, then revisited these plots every year to examine and track changes in the coral community — i.e., how many corals of a given species had died compared with new juveniles recruited to the reef.

“Although it appeared that the overall state of the coral reefs at Eilat was quite good and every year we found many new corals recruiting to the reefs, for those species that are suffering from the breakdown in spawning synchrony, there was a clear lack of recruitment of new juvenile generations, meaning that some species that currently appear to be abundant may actually be nearing extinction through reproductive failure,” says Shlesinger.

The future of corals?

“Several possible mechanisms may be driving the breakdown in spawning synchrony that we found,” Prof. Loya concludes. “For example, temperature has a strong influence on coral reproductive cycles. In our study region, temperatures are rising fast, at a rate of 0.31 degrees Celsius per decade, and we suggest that the breakdown in spawning synchrony reported here may reflect a potential sublethal effect of ocean warming. Another plausible mechanism may be related to endocrine (hormonal) disrupting pollutants, which are accumulating in marine environments as a result of ongoing human activities that involve pollution.”

“Regardless of the exact cause leading to these declines in spawning synchrony, our findings serve as a timely wake-up call to start considering these subtler challenges to coral survival, which are very likely also impacting additional species in other regions,” says Shlesinger. “On a positive note, identifying early-warning signs of such reproductive mismatches will contribute to directing our future research and conservation efforts toward the very species that are at potential risk of decline, long before they even display any visible signs of stress or mortality.”

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