Tag: Environment

Corals on Drugs: A Threat We Can’t Ignore

Written by AUFTAU on 1 October 2024. Posted in Newsroom.

Severe environmental contamination: A new study from Tel Aviv University and the Steinhardt Museum of Natural History detected traces of 10 common medications in coral samples collected from both shallow and deep sites in the Gulf of Eilat. Sulfamethoxazole, an antibiotic used for respiratory and urinary tract infections, was found in 93% of the sampled corals.

The alarming study was led by Prof. Noa Shenkar of TAU’s School of Zoology, Faculty of Life Sciences and Steinhardt Museum of Natural History, and her PhD student Gal Navon, in collaboration with the Hydrochemistry laboratory led by Prof. Dror Avisar at TAU’s Porter School of Environment and Earth Sciences. The results were published in the prestigious journal Environmental Pollution.

אלמוג אבן מסוג FAVITES

The stony coral species Favites (Photo Credit: Prof. Noa Shenkar).

“In this first-of-its-kind study, we conducted a large-scale investigation for detection of pharmaceuticals in corals”, says Prof. Shenkar. “We sampled 96 reef-building stony corals representing two types, Acropora sp. and Favites sp., in shallow sites (5-12 meters) as well as deeper sites beyond the limits of recreational diving (30-40 meters). We were surprised to find an extensive presence of medications even in the deep-water corals – which usually escape contaminations affecting corals in shallower areas”.

A Cocktail of Drugs Found in Coral Reefs

The researchers obtained a list of the most commonly used pharmaceuticals in Israel from Clalit Health Services. Testing for 18 of these compounds, they detected 10 of them in the coral samples. Not even a single sample, retrieved from either shallow or deep water, was found to be drug-free. The 10 pharmaceuticals found in the corals belonged to different categories: antibiotics, blood pressure medications, antiplatelet agents, calcium channel blockers, laxatives, proton pump inhibitors, statins and antidepressants.

“What does the presence of pharmaceuticals in corals actually mean? Clearly, the corals did not receive a prescription for antibiotics from their doctor”, explains Prof. Shenkar. “These medications are taken by humans to affect a certain receptor or biological pathway, and they can also impact other organisms. Previous studies, conducted by both our lab and others, have revealed many examples of this negative impact: estrogen from birth control contraceptive pills induces female features in male fish, impairing reproduction in certain species; Prozac makes some crabs aggressive and reckless; and antidepressants damage the memory and learning abilities of squids. There is no reason to believe that corals should be immune to such effects. For instance, if our pharmaceuticals should disrupt the spawning synchrony of coral populations, it would take us a long time to notice the problem, and when we do, it might be too late”.

פרופ' נועה שנקר וחברים ימיים

Prof. Noa Shenkar.

“Stony corals build coral reefs, and the types we studied are very common in the Gulf of Eilat”, adds Gal Navon. “Coral reefs are a cornerstone of marine biodiversity. They provide food, shelter, and spawning sites to numerous species, and support the human fishing and tourism industries. Today this delicate ecosystem is under pressure as a result of climate change, pollution, and overfishing. The presence of pharmaceuticals in coral tissues adds another layer of concern, indicating that human activities even contaminate faraway marine environments”.

“Clearly these medications save lives, and we have no intention of requesting people to reduce their use”, says Prof. Shenkar. “However, we must develop new sewage treatment methods that can effectively handle pharmaceutical compounds. Also, each of us must dispose of old medications in ways that do not harm the environment. Ultimately these drugs come back to us. I know people who avoid medications, but when they eat a fish, they might unknowingly consume a ‘cocktail’ of drug residues absorbed by the fish from the marine environment”.

Unlocking Green Energy from Microscopic Plants

Written by AUFTAU on 15 September 2024. Posted in Newsroom.

Recent reports that 2023 was the world’s hottest year on record highlights the urgency of mitigating climate change. One unavoidable change will be to clean up the energy sector, which currently produces 70% of industrial waste including greenhouse gases and ozone-eroding chemicals. The solution may come in the form of a tiny single-celled organism which most may recognize as the green layer on top of lakes and ponds: algae. Tamar Elman, a Tel Aviv University post-doctoral researcher in the lab of Iftach Yacoby at the Wise Faculty of Life Science, has discovered a microalgae species with a mutation which produces large amounts of hydrogen gas, a promising clean energy source. After completing a course at TAU’s Entrepreneurship Center, she is building a startup to figure out how this hydrogen production might be harnessed and industrialized.

An Accidental Discovery

Hydrogen gas is a very clean source of energy because its only byproduct is water vapor. “Unfortunately,” says Elman, “because it does not naturally accumulate anywhere in large amounts, producing hydrogen gas in a usable form does produce carbon waste. So there is a race right now to create a totally green production method that is also scalable and profitable.”

“There is a race right now to create a totally green production method that is also scalable and profitable.”

One natural source of hydrogen gas is microalgae, which is found in most habitats around the world and grows easily. In 2021, Elman was trying to increase the small amounts of hydrogen gas produced by microalgae in the TAU Yacoby lab. “Microalgae are considered plants because they perform photosynthesis, using solar energy to transform carbon dioxide into sugars for nourishment. However, green algae also have a built-in “circuit breaker” that burns off any excess solar energy by converting it to hydrogen gas. Unfortunately, hydrogen production is usually shut down quickly by other functions of the algae.

One day, Elman and Prof. Yacoby tested a new culture and saw the hydrogen levels reaching unprecedented heights. “We thought we were seeing a mistake in the hydrogen measuring device. We almost threw out the culture!” Says Elman. “But when we tried it on a different device and got the same results, we realized we had found a mutated algae strain that naturally overcame the barriers to continued hydrogen gas production.”

Scaling Up

Upon publishing a paper in 2022 on their discovery, Elman and Prof. Yacoby garnered quite a bit of interest from the scientific community. The two decided to capitalize on the buzz, delving further into experimentation on their mutation. Elman also won a grant from the Israeli Innovation Authority which required she take a course on breaking into industry at TAU’s Entrepreneurship Center.

Elman and Yacoby nailed down their idea to produce hydrogen gas for the energy sector and to work with the food industry to sell the used algae, which is left with high nutritional value after the production process.

Elman and Prof. Yacoby hope to industrialize microalgae-based hydrogen gas production. (Photo: Tel Aviv University)

The two discovered that scaling up creates its own host of challenges, as processes that work at small scales may not always translate proportionally. Elman realized she would need a very simple way to induce hydrogen production in the algae. “It’s almost comical how basic this method is,” she says of her solution. “All I do is give the algae some concentrated acid and let them sit in the dark for two hours breathing oxygen. Then I open the windows to let light in, and the algae start producing hydrogen! It’s practically too simple to market, but it really works.”

Elman spent the last year gathering her data and creating material for investors and industry stakeholders with the help of her Entrepreneurship Center team. Now, she is meeting with investors. “Even though it’s very difficult, I know I would regret not trying. And it’s an amazing feeling to see my research lead to something concrete.”

Her next steps are, she hopes, to build a large photobioreactor that can be used for larger-scale experiments and production.

Thinking Like an Entrepreneur

To learn what is needed to create a startup and collaborate with industry, Elman participated in a course called JumpTAU which brought together Arab and Jewish students in mixed startup-building teams at TAU’s Entrepreneurship Center. For months, the teams received intensive lectures, individual guidance and networking opportunities from industry experts and dedicated mentors.

“Entrepreneurship is a different type of thinking. I had to figure out who my audience was and how to frame my work as beneficial to them.”

After performing scientific research for 9 years, says Elman, “entrepreneurship is a really different type of thinking. I discovered that customers and investors aren’t interested in science for science’s sake, so I had to figure out who my audience was and how to frame my work as beneficial to them. Now a year later, I have a professional slide deck I can proudly show to investors.”

She felt particularly supported by the mentors and Center Director Yair Sakov, all of whom she says she can still turn to for ongoing counsel. “I really feel like those at the Center care about my success.”

Just Like Us: Retired Eagles Like to Stay In

Written by AUFTAU on 8 September 2024. Posted in Newsroom.

A new Tel Aviv University study, the first of its kind, has revealed that vultures, much like humans, experience changes in movement habits and social relationships as they age. Young vultures frequently move between roosting sites and “hang out with friends”. During adolescence, they spend about half their nights at a permanent roosting site (“home”) and the other half at other sites. In old age, however, vultures scale back on socializing, preferring to “stay home”. The study, which involved 142 Eurasian Griffon Vultures (Gyps fulvus) in Israel, is among the few to shed light on the behavioral changes in aging animals in the wild.

The study, led by Dr. Marta Acácio as part of her post-doctoral research in Dr. Orr Spiegel’s laboratory at Tel Aviv University’s School of Zoology, was conducted in collaboration with Prof. Noa Pinter-Wollman of the University of California, Los Angeles (UCLA) and several other researchers. The findings were published in the prestigious journal PNAS.

ד"ר מרתה אקסיו

Dr. Marta Acácio.

ד"ר אור שפיגל בזמן שחרור נשרים בכרמל. צילום: טובל'ה סולומון

Dr. Orr Spiegel. releasing tagged vultures (Photo credit: Tovale Solomon).

The Eagle Has Landed

Dr. Spiegel explains: “Vultures are a locally endangered species in Israel, with only about 200 individual vultures remaining. They are closely monitored to determine the best possible conservation methods. We thought about what else could be gleaned from the extensive database we have accumulated over the years and agreed it would be interesting to explore how vultures age. Tracking the same individuals in the wild over many years is often very challenging. However, the transmitters we use to monitor the population provided a rare opportunity to observe the aging process in vultures specifically and in animals generally”.

The researchers utilized a database accumulated over 15 years from GPS devices attached to 142 vultures that tracked them for periods of up to 12 years. The vulture, a social bird, sleeps in roosts on cliffs. By cross-referencing the vultures’ ages with the GPS data on their roosting sites, the researchers discovered that as the vultures aged, they increasingly preferred to stay at the same roosting site.

Aging vulture being monitored (Photo credit: Tovale Solomon).

Home Sweet Home

Dr. Spiegel: “It turns out that aging vultures behave a bit like humans and are more inclined to stay at home. When they’re young, vultures like to explore new sites and frequently move between places; the likelihood that a young vulture will sleep at the same site two nights in a row is low. When they reach adolescence at the age of five, this behavior stabilizes, and as adults they spend 50 percent of their nights at the same site and the other 50 percent at other sites. When they are old, from the age of 10 onwards, they no longer have the energy to be ‘out and about’, and return consistently to the same site. Furthermore, when adult vultures do change sites, they do so in a predictable pattern: for example, one night in Ein Avdat, the next in the Small Crater, and the next in Nahal Golhan, following a fixed order. Of course, it could be argued that older vultures move less not because they are old, but because they avoid taking risks in the first place, which is how they reached the age they did. But here we are talking about the exact same individual birds: those who were adventurous at the age of five became more sedentary by age ten”.

Elder Eagles’ Poisoning

According to Dr. Spiegel, these fascinating findings on the aging of birds also have very practical implications for conservation efforts. “This new study can help us better protect vultures’ roosting sites in the wild. Additionally, we have now seen that older vultures have fewer social connections, which can help us to prevent poisoning. The transmitters are connected to a system that sends an alert to the Israel Nature and Parks Authority, and to us by phone, if the vulture is not moving or has landed in a dangerous place, indicating that it may have been poisoned.

איסוף נשרים מתים בעקבות הרעלה ברמת הגולן על ידי פקחי רשות הטבע והגנים. צילום: רשות הטבע והגנים

Collecting dead vultures following poisoning in the Golan Heights by Nature and Parks Authority rangers (Photo credit: Nature and Parks Authority).

Unfortunately, this happens frequently. The danger arises when a vulture descends on a poisoned goat carcass, not knowing that a farmer has poisoned the carcass in order to kill stray dogs. Being social birds, vultures do not come down alone, leading to the risk of dozens of vultures dying at once. Understanding how wide the poisoned vulture’s social circle is will significantly help in mitigating the damage”.

It is important to note that vultures play an important ecological role in the disposing of carcasses. Studies have shown that the extinction of vultures ultimately leads to the loss of human lives, due to the rise of diseases such as rabies. In India, for example, a recently published study revealed that the extinction of vultures due to poisoning resulted in the deaths of half a million people over the course of five years.

Eilat’s Sponges’ Unique Way to Deter Predators

Written by AUFTAU on 5 September 2024. Posted in Newsroom.

A new study at Tel Aviv University found that sponges in the Gulf of Eilat have developed an original way to keep predators away. The researchers found that the sponges contain an unprecedented concentration of the highly toxic mineral molybdenum (Mo). In addition, they identified the bacterium that enables sponges to store such high concentrations of this precious metal and unraveled the symbiosis between the two organisms. The study was led by PhD student Shani Shoham and Prof. Micha Ilan from TAU’s School of Zoology. The paper was published in the leading journal Science Advances.

שני שוהם ורז מרום מוסקוביץ'

Two Ph.D. candidate Shani Shoham (right) and Raz Marom (Moskovich) happy to finally collect a sponge sample (in the bag) after several dives.

The researchers explain that sponges are the earliest multicellular organisms known to science. They live in marine environments and play an important role in the earth’s carbon, nitrogen, and silicon cycles. A sponge can process and filter seawater 50,000 times its body weight daily. With such enormous quantities of water flowing through them, they can accumulate various trace elements – and scientists try to understand how they cope with toxic amounts of materials like arsenic and molybdenum.

The Hidden Shine of the Sponge

PhD student Shani Shoham: “20 to 30 years ago, researchers from our lab collected samples of a rare sponge called Theonella conica from the coral reef of Zanzibar in the Indian Ocean and found a high concentration of molybdenum. Molybdenum is a trace element, important for metabolism in the cells of all animals including humans, and widely used in industry. In my research, I wanted to test whether such high concentrations are also found in this sponge species in the Gulf of Eilat, where it grows at depths of more than 27 meters. Finding the sponge and analyzing its composition I discovered that it contained more molybdenum than any other organism on earth: 46,793 micrograms per gram of dry weight.”

ככה זה נראה תחת מיקרוסקופ אור: אגירת מוליבדן בחיידק Entotheonella, ניתן להבחין בצבע הכחול בוקואולות (צילום: שני שהם)

Here’s what it looks like under a light microscope: Molybdenum accumulation in the bacterium Entotheonella. You can see the blue in the vacuoles. (Photo: Shani Shoham).

Shoham adds: “Like all trace elements, molybdenum is toxic when its concentration is higher than its solubility in water. But we must remember that a sponge is essentially a hollow mass of cells with no organs or tissues. Specifically in Theonella conica, up to 40% of the body volume is a microbial society – bacteria, viruses, and fungi living in symbiosis with the sponge. One of the most dominant bacteria, called Entotheonella sp., serves as a ‘detoxifying organ’ for accumulating metals inside the body of its sponge hosts. Hoarding more and more molybdenum, the bacteria convert it from its toxic soluble state into a mineral”.

“We are not sure why they do this. Perhaps the molybdenum protects the sponge, by announcing: “I’m toxic! Don’t eat me!”, and in return for this service the sponge does not eat the bacteria and serves as their host”

Sponge Bling: The Search for Molybdenum

Molybdenum is in high demand, mostly for alloys (for example, high-strength steel). Still, according to Shoham, it would be impracticable to retrieve it from sponges. The concentration is very high, but when translated into weight we could only get a few grams from every sponge, and the sponge itself is relatively rare. Sponges are grown in marine agriculture, mostly for the pharmaceutical industry, but this is quite a challenging endeavor. Sponges are very delicate creatures that need specific conditions”.

Shoham continues: “On the other hand, future research should focus on the ability of Entotheonellasp. bacteria to accumulate toxic metals. A few years ago, our lab discovered huge concentrations of other toxic metals, arsenic (As) and barium (Ba), in a close relative of Theonella conica, called Theonella swinhoei, which is common in the Gulf of Eilat. In this case, too, Entotheonellawas found to be largely responsible for hoarding the metals and turning them into minerals, thereby neutralizing their toxicity. Continued research on the bacteria can prove useful for treating water sources polluted with arsenic, a serious hazard which directly affects the health of 200 million people worldwide”.

פרופ' מיכה אילן

Prof. Micha Ilan.

How Do Lightning Storms Affect North Pole Sea Ice?

Written by Hilary on 16 May 2024. Posted in Newsroom.

TAU Research Shows that Lightning Storms are Causing Sea Ice to Melt Faster at the North Pole

A new international study with the participation of researchers from Tel Aviv University found that alongside the general warming of the globe, lightning storms have been directly hastening the ongoing process of sea ice retreat covering the Arctic Ocean. According to the researchers: “Until recently, lightning as a phenomenon was extremely rare in the Arctic region of the North Pole, due to the intense cold. However, due to the warming of the Earth, lightning storms have become more common there in the summers, and these storms further increase the melting process of the ice sheets – in a feedback loop”.

Prof. Colin Price and MSc student Tair Plotnik from the Department of Geophysics at TAU’s Porter School of the Environment and Earth Sciences participated in the study, alongside Dr. Anirban Guha and Dr. Joydeb Saha from Tripura University in India. The article was published in the journal Atmospheric Research.

Arctic’s Cold Reality: Understanding Rapid Ice Loss

Prof. Price explains: “The Arctic region is defined as the region located north of the 66.5° latitude. In the heart of this region, around the North Pole, there is no land, and due to the extreme cold conditions, the sea is covered with a thick layer of sea ice, which currently extends over about 8 million square kilometers. The white ice reflects the sun’s rays and thus contributes to the cooling of the Earth. But in recent decades, with the warming of the Earth, the ice cover has retreated at a rate of about 70,000 square kilometers per year, or 6.5% per decade (In this context, it is important to note that the temperature at the North Pole has been rising at an accelerating pace – about 4° until today, in contrast to about 1° on Earth as a whole).

Prof. Colin Price

The retreat of the ice increases the warming even further, because the dark areas of the ocean under the ice, which are getting bigger and bigger, absorb the sun’s rays that would normally be reflected in space. This is how a feedback loop is created: the retreat of the ice increases the warming, which in turn increases the melting of the ice, and the cycle repeats”.

Lightning’s Role in Polar Ice Melt

According to the researchers, the phenomenon of melting ice sheets at both poles is firstly attributed to the result of human activity due to the increase in the amount of greenhouse gases in the atmosphere, creating a kind of ‘blanket’ that preserves the heat and does not allow it to disperse into space. However, studies have not found a direct match between the greenhouse gas changes, which increase at a more or less constant rate every year, and the rate of sea ice melting, which varies immensely from year to year. This study sought to examine the possible effect of another factor – lightning storms – on the melting of the sea ice in the Arctic region.

The researchers explain that lightning, as a phenomenon, was extremely rare in the Arctic region until recently, due to the intense cold that prevails there. But in recent decades, apparently, due to global warming, lightning storms have been observed there in the summertime, when the sun does not set at all, heating the surface (Lightning storms form when the surface of the ground heats up, and pockets of air rise in the atmosphere, where they cool, condense, and become clouds that sometimes develop into thunderstorms).

To test their hypothesis that lightning storms contribute to the melting of the ice around the North Pole, the researchers compared two sets of data: images from NASA satellites that have been documenting the retreat of the ice in the Arctic Sea for more than 40 years, and lightning data collected by the global network WWLLN (wwlln.net) – which includes around 70 lightning detection stations, deployed in research institutions all over the world – one of which stands on the roof of the Faculty of Exact Sciences building at TAU. Prof. Price explains: “Lightning is the result of a massive electric field that is discharged at once and transmits radio waves that can be received even thousands of kilometers away from the lightning. The global network’s sensors detect and map thunderstorms anywhere on the planet, in real-time and non-stop. Cross-referencing the information from the various stations allows for an accurate determination of the location and time of each lightning strike detected, and thus, a global map of lightning over time is obtained. For this study, we collected data on lightning in the Arctic region during the summer months of June, July and August every year since 2010″.

Lightning Storms: Catalysts for Polar Ice Melt

A statistical analysis of the ice sheet retreat crossed with the number of lightning storms revealed a correlation: as the number of storms increased in a certain year, so did the melting of the sea ice increase that year. The researchers explain this by comparing thunderstorms to a giant vacuum cleaner, sucking water vapor up from the surface layer to the upper atmosphere (5-10km altitude), where it accumulates and acts like an additional blanket, trapping the surface heat from leaving, and increasing the surface temperature – just like man-made greenhouse gases. Another possibility observed in a previous study is that these same lightning storms lead to an increase in the formation of high cirrus clouds in the upper layers of the atmosphere – which also form a similar ‘blanket’.

Prof. Price concludes: “In our research, we found a clear statistical relationship between the number of lightning storms in the Arctic region in a certain year and the rate of sea ice melting that year. This means that the storms are another factor that increases the melting of the polar ice, producing a feedback loop: the initial melting of the ice increases the dark surface areas of the sea, which absorb more of the sun’s rays, warming up the waters, causing more melting, accelerating the rate of warming, which in turn increases the number of lightning storms, and the cycle repeats itself. As a result of this, and of the warming of the Earth in general, we expect that the frequency of lightning storms in the Arctic region will increase in the coming years, and with it, the rate of sea ice retreat in the Arctic Sea will accelerate”.

Researchers Produce Highly Efficient, Low-cost “Green” Hydrogen

Written by AUFTAU on 17 July 2023. Posted in Newsroom.

Tel Aviv University researchers have achieved a groundbreaking milestone by successfully producing highly efficient and low-cost “green” hydrogen. By harnessing the power of green electricity and utilizing a highly efficient biocatalyst, this innovative process generates hydrogen without any air pollution.

Hydrogen plays a vital role as raw material in both agriculture and industry. However, most of the hydrogen produced globally, approximately 95%, falls in the “black” or “gray” category. These types of hydrogen are derived from coal or natural gas, emitting a significant 9-12 tons of carbon dioxide for every ton of hydrogen produced.

Over 90% Efficiency

The new method was developed by doctoral student Itzhak Grinberg and Dr. Oren Ben-Zvi, under the guidance of Prof. Iftach Yacoby of the School of Plant Sciences and Food Security at the Faculty of Life Sciences and Prof. Lihi Adler-Abramovich of the School of Dental Medicine and the Center for Nanoscience and Nanotechnology. The promising research results were published in the prominent journal Carbon Energy, focusing on advanced materials and technology for clean energy and CO2 emission reduction.

“Hydrogen is very rare in the atmosphere,” explains Itzhak Grinberg, “although it is produced by enzymes in microscopic organisms, which receive the energy for this from photosynthesis processes. In the lab, we ‘electrify’ those enzymes, that is, an electrode provides the energy instead of the sun. The result is a particularly efficient process, with no demand for extreme conditions, that can utilize electricity from renewable sources such as solar panels or wind turbine. However, the enzyme ‘runs away’ from the electric charge, so it needs to be held in place through chemical treatment. We found a simple and efficient way to attach the enzyme to the electrode and utilize it.”

The researchers used a hydrogel (a water-based gel) to attach the enzyme to the electrode and were able to produce green hydrogen using a biocatalyst, and with over 90% efficiency; that is, over 90% of the electrons introduced into the system were deposited in the hydrogen without any secondary processes.

“We hope that in the future, it will be possible to employ our method commercially, to lower the costs, and to make the switch towards using green hydrogen in industry, agriculture, and as a clean energy source.” – Dr. Oren Ben-Zvi

Prof. Iftach Yacoby explains that, “The material of the gel itself is known, but our innovation is to use it to produce hydrogen. We soaked the electrode in the gel, which contained an enzyme for producing hydrogen, called hydrogenase. The gel holds the enzyme for a long time, even under the electric voltage, and makes it possible to produce hydrogen with great efficiency and at environmental conditions favorable to the enzyme — for example, in salt water, in contrast to electrolysis, which requires distilled water.

Prof. Lihi Adler-Abramovich adds: “Another advantage is that the gel assembles itself — you put the material in water, and it settles into nanometric fibers that form the gel. We demonstrated that these fibers are also able to stick the enzyme to the electrode. We tested the gel with two other enzymes, in addition to the hydrogenase, and proved that it was able to attach different enzymes to the electrode.”

“Today, ‘green’ hydrogen is produced primarily through electrolysis, which requires precious and rare metals such as platinum along with water distillation, which makes the green hydrogen up to 15 times more expensive than the polluting ‘grey’ one, says Dr. Oren Ben-Zvi. “We hope that in the future, it will be possible to employ our method commercially, to lower the costs, and to make the switch towards using green hydrogen in industry, agriculture, and as a clean energy source.”

Due to Climate Change, More Animals will Become Extinct Outside of Nature Reserves than Within Them

Written by AUFTAU on 12 July 2023. Posted in Newsroom.

A new international study has found that amphibians and reptiles inhabiting the world’s nature reserves, or Protected Areas (PAs), will be better protected against climate change than species found outside of these areas, but are still likely to be harmed.

The research findings provide evidence, on a global scale, of the crucial role Protected Areas play in conserving amphibian and reptile biodiversity under human-induced climate change scenarios. The study reveals that more animals will become extinct because of climate change outside of Protected Areas than inside them — in the world in general and on most individual continents.

Protected Areas as Refuges

Prof. Shai Meiri of Tel Aviv University’s School of Zoology, The George S. Wise Faculty of Life Sciences and The Steinhardt Museum of Natural History took part in the study, in collaboration with leading researchers from 19 countries. The study was published in the prestigious journal Nature Communications.

“Approximately 91% of the amphibian and reptile species we examined are protected, to some degree, in Protected Areas, and this proportion will remain unchanged under future climate change.” – Prof. Shai Meiri

The purpose of the study was to evaluate the effectiveness of existing Protected Areas in protecting the amphibians and reptiles living within them under future climate scenarios, as well as to identify conservation gaps in order to outline a road map for the development of conservation actions based on the current global network of Protected Areas.

“In this study, we collected distribution data for more than 14,000 species of amphibians and reptiles — about 70% of the known species — to perform a global assessment of the conservation effectiveness of Protected Areas in an era of climate change, using species distribution models,” explains Prof. Meiri. “Our analyses revealed that approximately 91% of the amphibian and reptile species we examined are protected, to some degree, in Protected Areas, and that this proportion will remain unchanged under future climate change. Furthermore, species protected in Protected Areas will lose smaller portions of their distribution ranges inside the nature reserve than outside of them. Therefore, the proportion of species within reserves is expected to increase.”

Relative Optimism

However, Prof. Meiri points out, “We predict that more than 300 of the amphibian species and 500 of the reptile species we studied will become extinct due to climate change in the coming decades, and probably also hundreds of species for which we did not have sufficient data to model. Our research highlights the importance of Protected Areas in providing refuge for amphibians and reptiles in face of climate change and points out areas where there are not enough nature reserves that can better preserve biodiversity around the world.”

“Despite the relative optimism emerging from the new research, the models still predict extremely high rates of loss of species and habitats due to climate change. Protected Areas do indeed protect the animals living within them, but nothing is foolproof.” – Prof. Shai Meiri

He adds: “We compiled a comprehensive global database with more than 3.5 million observation records spanning 5,403 amphibian species and 8,993 reptile species from online databases, fieldwork data, museum collections, and published references. For all species in our database, we predicted habitat availability according to current (1960–1990) climate data and future scenarios (for the years 2060–2080) at a high spatial resolution (1 km × 1 km) using species distribution models. Then, we evaluated the effectiveness of Protected Areas in conserving amphibians and reptiles by calculating the coverage of their distribution range inside and outside of Protected Areas, as well as the proportion of species for whom a significant portion of their distribution range (for example, 15% or 30%) is protected in PAs under current and future climate conditions (assuming that the future use of the land remains unchanged over the years — that is, that there will be no conversion of nature reserves into agricultural, industrial, or urban areas.)”

Prof. Meiri concludes: “Our evidence shows that the current global network of Protected Areas already plays an important role in preserving the global biodiversity of amphibians and reptiles, and will continue to do so under the expected future climate. However, many species do not live in the existing Protected Areas. These include, for example, many amphibians and reptiles in Mexico, Jamaica, the Andes, West Africa, South Africa, the southern and northern coast of Turkey, Yemen and other places. Moreover, in our study we could create a model for only about two-thirds of reptile and amphibian species. Good models can’t be created for the rarest species, which are known to be more vulnerable to extinction and less protected in Protected Areas. At the same time, it is important to remember that despite the relative optimism emerging from the new research, the models still predict extremely high rates of loss of species and habitats due to climate change. Protected Areas do indeed protect the animals living within them, but nothing is foolproof.”

New Studies Expose Coral Reef Crisis in Eilat

Written by AUFTAU on 28 May 2023. Posted in Newsroom.

Recent, unsettling studies conducted by Tel Aviv University have unveiled a deadly epidemic responsible for the widespread decimation of black sea urchins in the Mediterranean Sea and the Gulf of Eilat. Over the span of just a few months, the entire population of black sea urchins in Eilat was eradicated. For instance, within a few weeks, thousands of sea urchins inhabiting a site near the northern shore of the Gulf of Eilat perished. The severity of the epidemic is such that only skeletal remains of black urchins now occupy the site. Disturbingly, similar occurrences have been observed at various other locations in the Gulf of Eilat, as well as in neighboring countries including Jordan, Egypt, Saudi Arabia, Greece, and Turkey.

“At first we thought it was some kind of pollution or poisoning, or a local chemical spill (…) but when we examined additional sites in Eilat, Jordan, and Sinai, we quickly realized that this was not a local incident. All findings pointed to a rapidly spreading epidemic.” – Dr. Omri Bronstein.

Unveiling Deadly Epidemic

The studies were led by Dr. Omri Bronstein and PhD students Rotem Zirler, Lisa-Maria Schmidt, Gal Eviatar, and Lachan Roth from the School of Zoology, at The George S. Wise Faculty of Life Sciences, and The Steinhardt Museum of Natural History at Tel Aviv University. The papers were published in Frontiers in Marine science and Royal Society Open Science.

The researchers underscore the vital importance of sea urchins, particularly the long-spined Diadema setosum, as keystone species essential for the thriving equilibrium of coral reefs. They express a pressing concern, stating, “It must be understood that the threat to coral reefs is already at an all-time peak, and now a previously unknown variable has been added. This situation is unprecedented in the documented history of the Gulf of Eilat.”

According to the researchers’ hypothesis, the cause of the deadly epidemic can be attributed to a pathogenic ciliate parasite that has spread from the Mediterranean to the Red Sea. In response to the gravity of the situation, an urgent report outlining the current state has been submitted to the Israel Nature and Parks Authority, instigating deliberation on emergency measures to safeguard Israel’s coral reefs.

“Sea urchins in general, and Diadema setosum in particular, are considered key species essential for the healthy functioning of coral reefs. The sea urchins are the reef’s ‘gardeners’ – they feed on the algae and prevent them from taking over and suffocating the corals that compete with them for sunlight.” – Dr. Omri Bronstein

Dr. Omri Bronstein and a dying sea urchin

“At first we thought it was some kind of pollution or poisoning, or a local chemical spill, from the industry and hotels in the north of the Gulf of Eilat, but when we examined additional sites in Eilat, Jordan, and Sinai, we quickly realized that this was not a local incident,” explains Dr. Bronstein. “All findings pointed to a rapidly spreading epidemic. Similar reports are coming in from colleagues in Saudi Arabia. Even sea urchins that we grow for research purposes in our aquariums at the Interuniversity Institute, and sea urchins at the Underwater Observatory Marine Park in Eilat, contracted the disease and died, probably because the pathogen got in through the pumping systems.”

Dr. Bronstein describes it as a fast and violent death: “Within just two days a healthy sea urchin becomes a skeleton with massive tissue loss. While some corpses are washed ashore, most sea urchins are devoured while they are dying and unable to defend themselves, which could speed up contagion by the fish who prey on them.”

Invasion and Vanishing Species

In recent years, Dr. Bronstein’s research group has dedicated their efforts to the investigation of marine invasions, with a specific focus on the long-spined Diadema setosum. “Until recently, the black sea urchins with long spines, familiar to many of us, was one of the dominant species in Eilat’s coral reef,” reflects Dr. Bronstein. “Sea urchins in general, and Diadema setosum in particular, are considered key species essential for the healthy functioning of coral reefs. The sea urchins are the reef’s ‘gardeners’ – they feed on the algae and prevent them from taking over and suffocating the corals that compete with them for sunlight. Regrettably, these once-thriving sea urchins have vanished from the Gulf of Eilat and are quickly disappearing from constantly expanding parts of the Red Sea further to the south,” shares Dr. Bronstein with a sense of lament.

A dying urchin in the Mediterranean Sea (photo: Dr. Omri Bronstein)

Several months ago, Dr. Bronstein was alerted to the initial reports of widespread mortality by colleagues in Greece and Turkey, where the sea urchins had invaded, likely via the Suez Canal. “In 2006, the first sighting of this species of sea urchin occurred in the southern regions of Turkey,” Dr. Bronstein adds. This phenomenon, known as biological invasion, carries far-reaching ecological implications, pervasively affecting the eastern Mediterranean, particularly along Israel’s coastline. “We have been monitoring the dynamics of this species’ invasion in the Mediterranean since its first emergence,” he shares.

In 2016, they discovered the first Diadema setosum sea urchin along Israel’s Mediterranean coastline – a lone urchin sighted at Gordon Beach in Tel Aviv. For over a decade since the first discovery in Turkey, the Mediterranean populations of these sea urchins remained small and usually hidden. However, since 2018 the sea urchin population in the Mediterranean has been growing exponentially, reaching a state of population explosion – with giant populations of thousands and even tens of thousands found in Greece and Turkey.

“The window of opportunity for preserving a thriving population of this species in Eilat has regrettably closed. To establish a safeguard population, we must act without delay, by preserving healthy individuals from the Israeli Mediterranean before the encroaching disease from the north reaches this region.” Dr. Omri Bronstein

“However, during the course of our research, while scrutinizing the invasion of sea urchins in the Mediterranean, we began to receive reports on sudden extensive mortality,” says Dr. Bronstein. “While the extinction of an invasive species is supposedly not a bad thing, we must be aware of two major risks: Firstly, we don’t yet know how this mortality and its causes might impact local species in the Mediterranean. Secondly, and of far greater significance, the geographic proximity shared by the eastern Mediterranean and the Red Sea provides a potential conduit for the swift transmission of the pathogen into the Red Sea. As we feared and predicted, this is what appears to have happened.”

Dr. Bronstein and his research team (photo: courtesy of Dr. Omri Bronstein)

A Reminiscent Crisis

The massive loss of sea urchins reminded the TAU researchers of one of the most devastating events in marine ecology: the disappearance of the sea urchins in the Caribbean. Until 1983, the Caribbean coral reef thrived as a vibrant tropical ecosystem, much like the one in the Gulf of Eilat. But as the sea urchins vanished, the uncontrollable growth of algae took over, blocking sunlight from reaching the corals and forever altering the reef into a sea of algae.

Dr. Bronstein reveals, “Just last year, the Caribbean experienced another outbreak of the disease, resulting in the demise of the remaining urchin populations. However, unlike previous incidents, we now possess advanced scientific and technological resources to analyze the forensic evidence. Researchers from Cornell University successfully pinpointed the cause of mortality in the Caribbean: a pathogenic ciliate parasite. The identical pathology observed in the dying sea urchins of Greece, Turkey, and the Red Sea corroborates this finding.”

Dr. Bronstein’s pioneering research not only identified the unprecedented mass mortality of an invasive species in the Mediterranean but also shed light on the alarming decline of the widely prevalent sea urchin species, Diadema setosum. In a groundbreaking study, Dr. Bronstein issued a a warning that the epidemic plaguing the Mediterranean could extend its reach to the nearby Red Sea. Sadly, this cautionary prediction has become a disheartening reality.

Urgent Measures and Closing Window

“The gravity of the situation cannot be understated: the Red Sea is witnessing an alarming surge in mortality, surpassing the extent observed in the Mediterranean. Looming in the background is an ominous uncertainty: What is the exact cause of the sea urchin die-offs? Is it the same Caribbean pathogen or an entirely new and unfamiliar factor? Regardless, it is evident that this pathogen spreads through water, and we anticipate a rapid escalation of sickness and demise among the entire population of these sea urchins in both the Mediterranean and the Red Sea.”

“In my view, it is imperative that we swiftly establish a safeguard population for these sea urchins, ensuring the potential for their reintroduction into the wild. Similar to the approach taken with COVID-19, the trajectory of this epidemic remains uncertain. Will it eventually subside on its own, or persist for years, radically transforming coral reefs? However, unlike the COVID-19 pandemic, there are no available vaccines or treatments for the afflicted sea urchins. Hence, our efforts must be steadfastly directed towards prevention. The window of opportunity for preserving a thriving population of this species in Eilat has regrettably closed. To establish a safeguard population, we must act without delay, by preserving healthy individuals from the Israeli Mediterranean before the encroaching disease from the north reaches this region. While this is a complex undertaking, it is imperative if we aspire to secure the future of this unique species, which plays a critical role in the destiny of coral reefs,” concludes Dr. Bronstein.

Plants Emit Sounds – Especially When Stressed

Written by AUFTAU on 1 April 2023. Posted in Newsroom.

In a world first, Tel Aviv University researchers record and analyze sounds distinctly emitted by plants.

Do you talk to your plants? While you may not be able to hear them, yaour plants could very well be chatting away as well (perhaps they are not such great listeners after all), and that’s especially true if they are having a bad day (did you forget to water them again?). For the first time in the world, TAU researchers recorded and analyzed sounds distinctly emitted by plants. The click-like sounds, resembling the popping of popcorn, are emitted at a volume similar to human speech, but at high frequencies, beyond the hearing range of the human ear. The researchers: “We found that plants usually emit sounds when they are under stress, and that each plant and each type of stress is associated with a specific identifiable sound. While imperceptible to the human ear, the sounds emitted by plants can probably be heard by various animals, such as bats, mice, and insects.”

“From previous studies we know that vibrometers attached to plants record vibrations, but do these vibrations also become airborne soundwaves – sounds that can be recorded from a distance? Our study addressed this question, which researchers have been debating for many years.” Prof. Lilach Hadany

Resolving Old Scientific Controversy

The study was led by Prof. Lilach Hadany from the School of Plant Sciences and Food Security at The George S. Wise Faculty of Life Sciences, together with Prof. Yossi Yovel, Head of the Sagol School of Neuroscience and faculty member at the School of Zoology and the Steinhardt Museum of Natural History, and research students Itzhak Khait and Ohad Lewin-Epstein, in collaboration with researchers from the Raymond and Beverly Sackler School of Mathematical Sciences, the Institute for Cereal Crops Research, and the Sagol School of Neuroscience – all at Tel Aviv University. The paper was published in the prestigious scientific journal Cell.

“From previous studies we know that vibrometers attached to plants record vibrations,” says Prof. Hadany. “But do these vibrations also become airborne soundwaves – sounds that can be recorded from a distance? Our study addressed this question, which researchers have been debating for many years.”

WATCH: Prof. Yossi Yovel and Prof. Lilach Hadany on their findings

At the first stage of the study the researchers placed plants in an acoustic box in a quiet, isolated basement with no background noise. Ultrasonic microphones recording sounds at frequencies of 20-250 kilohertz (the maximum frequency detected by a human adult is about 16 kilohertz) were set up at a distance of about 10cm from each plant. The study focused mainly on tomato and tobacco plants, but wheat, corn, cactus and henbit were also recorded.

“Our findings suggest that the world around us is full of plant sounds, and that these sounds contain information – for example about water scarcity or injury (…) We believe that humans can also utilize this information, given the right tools – such as sensors that tell growers when plants need watering.” – Prof. Lilach Hadany

Mapping Plants’ Complaints with AI

Before placing the plants in the acoustic box, the researchers subjected them to various treatments: some plants had not been watered for five days, in some the stem had been cut, and some were untouched. Prof. Hadany explains that their intention was to test whether the plants emit sounds, and whether these sounds are affected in any way by the plant’s condition: “Our recordings indicated that the plants in our experiment emitted sounds at frequencies of 40-80 kilohertz. Unstressed plants emitted less than one sound per hour, on average, while the stressed plants – both dehydrated and injured – emitted dozens of sounds every hour.”

The recordings collected in this way were analyzed by specially developed machine learning (AI) algorithms. The algorithms learned how to distinguish between different plants and different types of sounds, and were ultimately able to identify the plant and determine the type and level of stress from the recordings. Moreover, the algorithms identified and classified plant sounds even when the plants were placed in a greenhouse with a great deal of background noise.

In the greenhouse, the researchers monitored plants subjected to a process of dehydration over time and found that the quantity of sounds they emitted increased up to a certain peak, and then diminished.

“In this study we resolved a very old scientific controversy: we proved that plants do emit sounds!” says Prof. Hadany. “Our findings suggest that the world around us is full of plant sounds, and that these sounds contain information – for example about water scarcity or injury. We assume that in nature the sounds emitted by plants are detected by creatures nearby, such as bats, rodents, various insects, and possibly also other plants – that can hear the high frequencies and derive relevant information. We believe that humans can also utilize this information, given the right tools – such as sensors that tell growers when plants need watering. Apparently, an idyllic field of flowers can be a rather noisy place. It’s just that we can’t hear the sounds.”

In future studies the researchers will continue to explore a range of intriguing questions, such as: What is the mechanism behind plant sounds? How do moths detect and react to sounds emitted by plants? Do other plants also hear these sounds? Stay tuned.

The research team

Does a Food Sharing Economy Benefit the Environment?

Written by AUFTAU on 14 February 2023. Posted in Newsroom.

According to researchers it depends on how the saved money is spent.

Researchers from Tel Aviv University and Ben Gurion University explored the true benefit of the so-called “digital food sharing economy”: when people advertise and pass on surplus food items to others instead of throwing them away. Is this indeed an environmentally friendly practice that saves resources and significantly reduces harm to the environment? The researchers focused on the effectiveness of food sharing according to three environmental indicators: water depletion, land use, and global warming. They found that a significant proportion of the benefit to the environment is offset when the money saved is then used for purposes that have a negative environmental impact.

“While there is nothing new about sharing food, digitalization has lowered transaction costs substantially, allowing food to be shared not only within social circles of family and friends but also with absolute strangers.” Dr. Tamar Makov

Sharing Food Got Cheaper

The study was led by Tamar Meshulam, under the guidance of Dr. Vered Blass of the Porter School of Environment and Earth Sciences at the Raymond & Beverly Sackler Faculty of Exact Sciences of Tel Aviv University and Dr. Tamar Makov of Ben-Gurion University, and in collaboration with Dr. David Font-Vivanco, an expert on “rebound effect.” The article won the award for the “Best Article” at the PLATE (Product Lifetimes and the Environment) conference and was published in the Journal of Industrial Ecology.

“Food waste is a critical environmental problem,” explains Tamar Meshulam: “We all throw away food, from the farmer in the field to the consumer at home. In total, about a third of the food produced in the world is lost or wasted. This wasted food is responsible for roughly 10% of GHG [greenhouse gas] emissions, and the land area used to grow food that is then wasted is equal in size to the vast territory of Canada! That’s why it is so important to look for ways to reduce food waste and examine their potential contribution to mitigating climate change.”

According to Dr. Tamar Makov, “Internet platforms for sharing food are gaining popularity all over the world and are seen as a natural solution that can help tackle both food waste and food insecurity at the same time. While there is nothing new about sharing food, digitalization has lowered transaction costs substantially, allowing food to be shared not only within social circles of family and friends but also with absolute strangers.”

“Is it possible that at least some of the money saved is then spent on carbon intensive products and services that negate the benefit of sharing? (…) In this study, we sought to examine this troubling issue in depth.” Dr. Vered Blass

From left to right: Dr. Vered Blass (Tel Aviv University) and Dr. Tamar Makov (Ben-Gurion University)

Where Does the Money Go?

“At the same time, sharing platforms as well as other digitally enabled food waste reduction platforms (e.g., too good to go) can save users a lot of money, which raises the question of what do people typically do with such savings? Considering what people do with the money they save via sharing platforms is critical for evaluating environmental impacts,” notes Makov.

Dr. Vered Blass adds: “Is it possible that at least some of the money saved is then spent on carbon intensive products and services that negate the benefit of sharing?” She offers an example to illustrate: “Let’s say that for one month a young couple lives only on food they obtained for free through a sharing platform, and then they decide to use the money they saved to fly abroad. In such a case, it’s obvious that the plane they will be flying in creates pollution that harms the environment more than all the benefits of sharing. In this study, we sought to examine this troubling issue in depth.”

“As long as our savings are measured in money, and the money is used for additional expenses, the rebound effect will erode our ability to reduce environmental burdens through greater efficiency.” The research team

“Rebound Effect” Detected

The researchers chose to focus on the app OLIO, an international peer-to-peer food-sharing platform, and specifically on its activity in the United Kingdom between the years 2017 and 2019.

Combining models from the fields of industrial ecology, economics, and data science, they measured the benefits of sharing food using three environmental indicators: global warming, the depletion of water sources, and land use. To understand how OLIO users spend their savings they used statistical data published by the UK Office for National Statistics on household spending by consumption purpose to as COICOP (classification of individual consumption according to purpose).

“The location in which the food-sharing took place allowed us to assign each collecting user to their UK income percentile,” shares Meshulam. “We found that about 60% of the app’s users belong to the bottom five deciles, while about 40% of the shares were carried out by the top five deciles. We also found that the second and tenth deciles made up a relatively large number of shares, so we chose to focus on them, along with data on the general population – what they spend their money on, and what the significance of these consumption habits is regarding the savings made possible by sharing.”

The researchers performed a variety of statistical analyses, which yielded fascinating findings. In many cases, there was a considerable gap, or “rebound effect” between the expected environmental benefit and the benefit that was attained.

This rebound effect changed depending on the population and the environmental impact category. Tamar Meshulam cites several examples: For the general population, 68% of the benefit was offset in the global warming category, about 35% was offset in the water depletion category, and about 40% was offset in the land use category. Furthermore, in households that used half of their savings on food, the rebound effect in all categories increased to 80-95%.

The researchers sum up: “The conclusion from our research is that the actual environmental benefits from efficiency improvements often fall short of expectations. This is because the infrastructures supporting human activities are still carbon intensive. As long as our savings are measured in money, and the money is used for additional expenses, the rebound effect will erode our ability to reduce environmental burdens through greater efficiency.”

The researchers also examined what the results would have been if the sharing had been conducted in 2011 (these results are not included in this article). A comparison with the findings of 2019 shows a significant improvement. The explanation for this is that in recent years, Britain has made great efforts to switch to renewable energies, and the impact of this is evident in the decrease of greenhouse gas emissions. The bottom line? The researchers conclude that “as our findings demonstrate, we need to combine a transition to green infrastructure with green consumerism. Each of these individually will not achieve the desired and critical impact needed for humanity and the planet.”

Featured image: Volunteers receive groceries for the elderly in Bat Yam, Israel during the coronavirus before the feast of Pesach (April 7, 2020) (Photo Credit: TAU)

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