How To Detect Extraterrestrial Life On Proxima B? (Astronomy)

Elisa Tabor and Abraham Loeb investigated the possibility of detecting artificial lights from proxima b. They found that James Webb Space Telescope will be able to detect LED type artificial lights. Their study recently appeared in Arxiv.

Proxima b as we all know, is one of the best targets outside of solar system in the search for extraterrestrial life. It resides in the habitable zone of its star “Proxima Centauri”. Recent study, suggested that Proxima Centauri b can sustain enormous areas of liquid water on its surface, potentially raising its prospects for harboring extraterrestrial life. The important question is, how can we detect it?

In 2011, Turner and Loeb proposed a concept which relies on the assumption that any intelligent life that evolved in the light from its nearest star is likely to have artificial lights that switches on during the hours of darkness. Considering this, Tabor and Loeb now examined how can we detect such artificial lights originating from Proxima b.

“Proxima Centauri b orbits in its star’s habitable zone, so it’s likely that the planet has become tidally locked with a permanent dayside and nightside. This exacerbates the need for artificial illumination that switches on during the hours of darkness.”

According to authors, if Proxima b has a permanent day and nightside, the civilization might illuminate the nightside using mirrors launched into orbit or placed at strategic points. In that case, the lights shining onto the permanent nightside should be extremely powerful, and thus more likely to be detected with James Webb Space Telescope (JWST).

“We have simulated lightcurves from Proxima b and compared curves corresponding to the reflected stellar spectrum to curves with artificial lights corresponding to a narrower spectrum such as for LEDs”

They have found that JWST will be able to show the existence of artificial illumination for standard LEDs 500 times more powerful than those currently found on Earth’s, and for artificial illumination of similar magnitude to Earth’s for a spectrum 10³ times narrower in frequency.

“We find that the James Webb Space Telescope (JWST) will be able to detect LED type artificial lights making up 5% of stellar power with 85% confidence and for the current level of artificial illumination on Earth, the spectral band must be 10³ times narrower.”

Finally, they concluded that, even if JWST will not be able to detect artificial illumination on Proxima b, future observatories like Large UV Optical Infrared Surveyor (LUVOIR) might be able to detect this artificial illumination.

Figure 1. The lightcurves from Proxima b calculated using Exoplanet Analytic Reflected Lightcurves (EARL), with three different coefficients Fai representing the percentage of stellar power being illuminated on the dark side of the planet. The blue curve represents Fai = 0.1, which equals the value they assume for the albedo. Thus the amount of artificial illumination on the night side is equal to the amount of light reflected from the day side. The green curve, for Fai = 0, represents no artificial illumination, so the night side is fully dark. Top panel: the planet to star ratio depends solely on the lune width. Bottom panel: the ratio depends on time (in days), orbital angular frequency, and inclination. © Tabor and Loeb

Reference: Elisa Tabor, Abraham Loeb, “Detectability of Artificial Lights from Proxima b”, Arxiv, pp. 1-4, 2021. https://arxiv.org/abs/2105.08081


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Two Compounds Can Make Chocolate Smell Musty and Moldy (Chemistry)

Chocolate is a beloved treat, but sometimes the cocoa beans that go into bars and other sweets have unpleasant flavors or scents, making the final products taste bad. Surprisingly, only a few compounds associated with these stinky odors are known. Now, researchers reporting in ACS’ Journal of Agricultural and Food Chemistry have identified the two compounds that cause musty, moldy scents in cocoa — work that can help chocolatiers ensure the quality of their products. 

Cocoa beans, when fermented correctly, have a pleasant smell with sweet and floral notes. But they can have an off-putting scent when fermentation goes wrong, or when storage conditions aren’t quite right and microorganisms grow on them. If these beans make their way into the manufacturing process, the final chocolate can smell unpleasant, leading to consumer complaints and recalls. So, sensory professionals smell fermented cocoa beans before they are roasted, detecting any unwanted musty, moldy, smoky or mushroom-like odors. Even with this testing in place, spoiled beans can evade human noses and ruin batches of chocolate, so a more objective assessment is needed for quality control. In previous studies, researchers used molecular techniques to identify the compounds that contribute to undesirable smoky flavors, but a similar method has not clarified other volatile scent compounds. So, Martin Steinhaus and colleagues wanted to determine the principal compounds that cause musty and moldy odors in tainted cocoa beans.

The researchers identified 57 molecules that made up the scent profiles of both normal and musty/moldy smelling cocoa beans using gas chromatography in combination with olfactometry and mass spectrometry. Of these compounds, four had higher concentrations in off-smelling samples. Then, these four compounds were spiked into unscented cocoa butter, and the researchers conducted smell tests with 15-20 participants. By comparing the results of these tests with the molecular content of nine samples of unpleasant fermented cocoa beans and cocoa liquors, the team determined that (–)-geosmin — associated with moldy and beetroot odors — and 3-methyl-1H-indole — associated with fecal and mothball odors — are the primary contributors to the musty and moldy scents of cocoa beans. Finally, they found that (–)-geosmin was mostly in the beans’ shells, which are removed during processing, while 3-methyl-1H-indole was primarily in the bean nib that is manufactured into chocolate. The researchers say that measuring the amount of these compounds within cocoa beans could be an objective way to detect off-putting scents and flavors, keeping future batches of chocolate smelling sweet.

The authors acknowledge funding from the German Ministry of Economic Affairs and Energy via the German Federation of Industrial Research Associations (AiF) and the Industrial Collective Research (IGF).

“Molecular Background of a Moldy-Musty Off-Flavor in Cocoa”
Journal of Agricultural and Food Chemistry

Featured image: Researchers have identified two compounds that can make chocolate smell musty and moldy. Credit: ivan_kislitsin/Shutterstock.com


Provided by American Chemical Society

New Strategy Improves Stability of Platinum Group Metal Catalysts (Chemistry)

Recently, a group led by Prof. WANG Junhu from the Dalian Institute of Chemical Physics (DICP) of the Chinese Academy of Sciences (CAS) constructed a novel type of strong metal-support interaction (SMSI) through the melamine/urea catalyst modification and oxidation atmosphere calcination, and developed a new strategy to improve the stability of platinum group metals (PGMs) catalysts.

This study was published in ACS Catalysis on May 4.

Prof. AO Zhimin from the Guangdong University of Technology and Prof. ZHANG Binsen from the Institute of Metals of CAS were also involved in the study.

The induced overlayer of SMSI often covers several catalytic active sites, leading to catalysts inactive in a degree. Moreover, the retreat of the overlayer upon reverse atmosphere treatment curtails the effect of SMSI on enhancing the catalytic performance of underlying metals, especially at elevated temperatures.

The classical SMSI induced by reduction atmosphere calcination between transition metal oxides and PGMs has been investigated. However, the encapsulation on the same catalysts occurred under oxidation condition is still unclear. 

The researchers found the evidence that PGMs nanoparticles could be encapsulated by an amorphous and permeable TiOx cover layer on titania-supported catalysts under oxidative atmosphere driven by melamine/urea. It was contrary to the condition needed for classical SMSI between Pt and TiO2.

Moreover, the formed overlayer was stabilized against re-oxidation at 400-600 °C in air, in sharp contrast to the retreat of TiOx overlayer by subsequent oxidation treatment in classical SMSI. And the formation mechanism of this kind of encapsulation was different from that of classical SMSI.

“The new strategy was further demonstrated on titania-supported Pd and Rh nanoparticles, and it provides a promising new way for designing supported PGMs-based catalysts with high activity and stability,” said Prof. WANG.


Reference: Shaofeng Liu, Haifeng Qi, Junhui Zhou, Wei Xu, Yiming Niu, Bingsen Zhang, Yang Zhao, Wei Liu, Zhimin Ao, Zhichong Kuang, Lin Li, Meng Wang, and Junhu Wang, “Encapsulation of Platinum by Titania under an Oxidative Atmosphere: Contrary to Classical Strong Metal–Support Interactions”, ACS Catal. 2021, 11, 10, 6081–6090.
https://doi.org/10.1021/acscatal.1c01347


Provided by Chinese Academy of Sciences

Scientists Report New Wideband Two-Dimensional Nonlinear Optical Materials and Devices (Chemistry)

Recently, Chinese scientists reported a new class of two-dimensional (2D) third-order nonlinear optical (NLO) materials, called metallated graphynes. The new material, exhibits broadband (at both 532 and 1064 nm) saturable absorption NLO property and high laser damage threshold.

Researchers prepared two free-standing mercurated graphyne nanosheets by applying an interface-assisted bottom-up method. The large-area nanosheets derived from the chemical growth have shown their layered molecular structural arrangement, controllable thickness and enhanced π-conjugation. The mercurated graphyne nanosheets are therefore having stable and outstanding broadband nonlinear saturable absorption properties.  

With the help of the absorption ability, the metallated graphynes are acting as saturable absorbers. And it has better pulse properties and Q-switched performances, especially comparing with traditional 2D materials (like graphene, black phosphorus).

The work reveals that the metallated graphyne materials can go beyond graphyne. The new material could not only be a new family of stable 2D carbon-rich materials under ambient conditions, but also possess unique properties and application prospects. It could be helpful in the future design of various structures for optoelectronic materials and devices.   

Besides, the nanosheets with controllable thickness and high transparency can be transferred on the optical glass and other substrates. It could be directly applied as free-standing films in optoelectronic devices.   

The new proposed nanosheet has advantages in optical property, mechanical processability and control of molecular dimensions. And this could be benefited the design of optoelectronic materials and fabrication of their devices in applications such as nonlinear optics, optical limiting, optical communications and so on. 

This work, published in Angewandte Chemie International Edition, was directed by the joint group of Prof. Wai-Yueng Wong from The Hong Kong Polytechnic University, Prof. XIE Zheng from the Technical Institute of Physics and Chemistry of the Chinese Academy of Sciences, and Prof. WANG Zhengping from Shandong University. 

Featured image: Chemical Structures, Interface-assisted Preparation, and Nonlinear Optical Passively Q-switched Performances of Metallated Graphynes (Image by Wong et al.)


Reference: Dr. Linli Xu, Dr. Jibin Sun et al., “Metallated Graphynes as a New Class of Photofunctional 2D Organometallic Nanosheets”, Angewandte Chemie, Volume 133, Issue 20 p. 11427-11435. https://doi.org/10.1002/ange.202014835


Provided by Chinese Academy of Sciences

New Methods Proposed to Characterize Polymer Lamellar Crystals (Chemistry)

Different from small molecules, polymer will fold into lamellar crystals during crystallization and further assemble into lamellar stacks. 

Synchrotron Small-Angle X-Ray Scattering (SAXS) is an important tool to characterize such nanoscale structure and understand polymer crystallization. However, its scattering mechanism in semi-crystalline polymers is not completely elucidated yet. 

Recently, a research group led by Prof. TIAN Xingyou from Institute of Solid State Physics, Hefei Institutes of Physical Science (HFIPS), proposed a complete set of new methods to characterize polymer lamellar crystals using SAXS. 

“We’ve been working on this novel models for four years, from theory to application” said LI Xiangyang from HFIPS. 

In 2019, the researchers first found that the existence of evanescent wave-induced scattering in transmission SAXS was possible. Moreover, the evanescent wave-induced scattering was much stronger than the scattering induced directly by incident X-ray, and the scattering of interfacial electrons within was the main origin of SAXS signal.

Then they started to try the approaches to obtain lamellar thickness, long period and lateral size. “Based on new SAXS image, we isolated the evanescent wave-induced scattering from the real scattering and reduced the influence of the scattering of bulk electrons, form factor and Porod scattering, obtaining the information on lamellar thickness and long period,” said LI.

It was assumed that some residual crystals existed in the structured melt, whose lateral size is larger than critical nucleation size. However, it is hard to be testified due to the difficulty in characterization. With the new methodologies, the researchers characterized residual crystals, demonstrating previous conjecture.

This work is supported by the National Natural Science Foundation of China.

Featured image: Melting (a) and recrystallization processes (b-d) after melting at different temperatures (Image by LI Xiangyang)


Reference: Xiangyang Li, Jianjun Ding et al., “Detection and characterization of folded-chain clusters in the structured melt of isotactic polypropyl­ene”, IUCrJ, 8(4), 2021. Link to paper


Provided by Chinese Academy of Sciences

Researchers Propose Novel Approach to Enhance Heterogeneous Photosynthesis of Azo- compounds (Chemistry)

Photocatalytic reactions, which allow unlocking some chemical transformations under mild conditions that are unavailable to conventional ground-state pathways, can save energy consumption and improve intrinsic safety of the processes. As a sustainable and low-carbon technology, it has high potential in the commitment to carbon peak and carbon neutrality.

Continuous flow chemistry can, to a large extent, migrate the “light limitation” problem in traditional batch protocols, and the use of heterogeneous photocatalysis can overcome the disadvantages of difficult catalyst recovery in homogeneous systems. However, effective handling of the solid photocatalysis in continuous flow still remains a challenge.

In a study published in Chemical Engineering Journal, a team led by Prof. TANG Zhiyong and Assoc. Prof. ZHANG Jie at Shanghai Advanced Research Institute of the Chinese Academy of Sciences reported a novel approach to utilize the solid photocatalysis in continuous flow without clogging with the employment of gas–liquid-solid segmented flow. This approach, owning to the inner recirculation in liquid segments and the formed thin film, ensures the effective suspension of solid catalysts in flow, resulting in enhanced mass transfer and irradiation.

Azobenzene and azoxybenzene are important precursors in pigment industry, electronic industry and pharmaceutical industry. In this study, the selective synthesis of azo- compounds from nitrobenzene by graphitic carbon nitride (g-C3N4) photocatalysis was selected as model photocatalytic reaction. Through visual flow experiments, the model reaction under gas-liquid-solid segmented flow was investigated thoroughly. Meanwhile, the effects of flow behavior on the photoreaction performance were quantified.

Besides, the researchers found that the continuous flow could greatly shorten the reaction time. The photocatalytic reaction performance was very sensitive to the gas-liquid-solid segmented flow conditions, which needs to be carefully tuned.

Increasing inert gas fraction resulted in more stable segmented flow with shorter liquid segments and thinker liquid film. The maximum productivity per volume of the continuous photo-microreactor reached 26.1 mmol/h*L. Benefiting from the advantage of “numbering-up”, this value was more than 500 times that of the batch reactor (80 L) reported in the open literature.

These results demonstrated great potential of gas-liquid-solid segmented flow in the field of heterogeneous photocatalysis. This study provides a new route to utilize the heterogenous catalysis in continuous flow, which can be applied to intensify the synthesis of functional materials, fine chemicals and active pharmaceutical ingredients.


Reference: Yuhang Chen, Yaheng Zhang, Hongwei Zou, Minglei Li, Gang Wang, Min Peng, Jie Zhang, Zhiyong Tang, Tuning the gas-liquid-solid segmented flow for enhanced heterogeneous photosynthesis of Azo- compounds, Chemical Engineering Journal, Volume 423, 2021, 130226, ISSN 1385-8947, https://doi.org/10.1016/j.cej.2021.130226. (https://www.sciencedirect.com/science/article/pii/S1385894721018143)


Provided by Chinese Academy of Sciences

Scientists Unravel Mechanism of Ion and Electron Migration in Composite Solid Electrolytes (Chemistry)

Scientists from the Advanced lithium-ion Battery Engineering Laboratory, Ningbo Institute of Materials Technology and Engineering (NIMTE) of the Chinese Academy of Sciences (CAS), revealed the mechanism in of ion and electron migration in composite solid electrolytes (CSEs) through the conductive atomic force microscopy (c-AFM), which facilitates the design of high-performance solid electrolytes. The study was published in Energy Storage Materials

Compared with the traditional lithium-ion (Li-ion) battery, the solid-state battery with solid materials as electrolyte has higher energy density and safety. As a combination of inorganic solid electrolytes (ISEs) and solid polymer electrolytes (SPEs), CSEs showed excellent contact with electrodes and high ionic conductivity. However, the role of inorganic particles and migration of Li-ions is still controversial. 

To address this issue, Dr. SHEN Cai and his colleagues at NIMTE prepared Li7La3Zr2O12-polyethylene oxide (LLZO-PEO) CSEs with different ratios of LLZO, i.e., 0, 50, 75 wt. %. The c-AFM was equipped with a quantitative nano-mechanical measurement module (QNM), which collected the topography and sample current while obtaining mechanical information. By virtue of the c-AFM, the effects of temperature and LLZO content on the migration of ion and electron in CSEs were investigated. 

At low temperatures, Li-ions can only migrate along the amorphous PEO regardless of LLZO content. The addition of LLZO lead to the formation of PEO amorphous region at the interface between LLZO and PEO, reducing the crystallinity and glass transition temperature of PEO.  

At high temperatures, Li-ions mainly migrated along the amorphous PEO when a small amount (i.e., 0 and 50 wt. %) of LLZO particles was added. With the increase of LLZO content (75 wt. %), LLZO particles formed a continuous ionic conductive network in the PEO matrix, and lithium ions migrated through LLZO particles.  

The as-prepared electrolyte showed dominant Li-ion migration, which was three orders of magnitude higher than the electronic current. In addition, the electronic current from PEO is much larger than that of LLZO, which indicates that the addition of LLZO can improve the electronic insulation of CSEs.  

Furthermore, due to the high modulus and excellent insulation properties of LLZO, the addition of LLZO into the electrolytes is expected to inhibit the growth of li dendrites in lithium anodes. 

This study revealed the influence of inorganic particle content and working temperature on the performance of CSEs, which provides novel insights into the design and development of CSEs for solid-state batteries.


Reference: Cai Shen, Yunbo Huang, Jingru Yang, Minjing Chen, Zhaoping Liu, Unraveling the mechanism of ion and electron migration in composite solid-state electrolyte using conductive atomic force microscopy, Energy Storage Materials, Volume 39, 2021, Pages 271-277, ISSN 2405-8297, https://doi.org/10.1016/j.ensm.2021.04.028. (https://www.sciencedirect.com/science/article/pii/S2405829721001707)


Provided by Chinese Academy of Sciences

Largest Genetic Study To Date On Bipolar Disorder (Medicine)

In cooperation with the University of Bonn, researchers studied a total of 400,000 people

Genetic factors contribute significantly to the development of bipolar disorder. The probably largest analysis to date on the hereditary factors involved has now been published. More than 40,000 affected individuals and 370,000 controls were included in the study; some 320 researchers around the globe were involved. Lead partners for the project included the Icahn School of Medicine, New York, the University of Oslo and the University Hospital Bonn. The results not only provide new insights into the genetic basis of the disease, but also into possible risk factors in living conditions or behavior. They are published in the journal “Nature Genetics”.

The name “bipolar disorder” is not a coincidence: The mood of those affected oscillates between two extremes. Sometimes they are so depressed for weeks that they barely manage to go about their daily activities. At other times, there are phases when they feel euphoric and full of energy, frantically pursuing their projects. The term “manic depression” has therefore become established in everyday language. Around one percent of all people develop the disease in the course of their lives. Their suffering is immense.

Risk factors include early childhood traumas such as abuse or the loss of a parent, but also, for example, a stressful lifestyle or the use of certain drugs. To a large extent, however, bipolar disorder is a matter of genes: Experts estimate the contribution of genetic makeup at 60 to 85 percent. Hundreds of genes are probably involved. “However, we only know a small part of them so far,” explains Jun.-Prof. Dr. Andreas Forstner. The researcher, who recently moved from the University of Marburg to a junior professorship at the Institute of Human Genetics at the University of Bonn and the Institute of Neuroscience and Medicine (INM-1) at Forschungszentrum Jülich, is one of the lead authors of the current study.

DNA lexicon compared at hundreds of thousands of sites

This greatly improves the understanding of the genetic basis. The international consortium searched the DNA of more than 400,000 participants for abnormalities. Each individual’s genetic blueprint is like a giant lexicon with around three billion letters. The content of this DNA lexicon differs from person to person. However, for people with bipolar disorder, at least the passages that relate somewhat to the disorder should be similar. And the researchers took advantage of this basic assumption: By comparing the DNA of their subjects at many hundreds of thousands of sites that occur variably in the population, they were able to identify genetic regions that are thought to contribute to the disease.

“In this way, we identified 64 gene loci associated with bipolar disorder,” explains Prof. Dr. Markus Nöthen, head of the Institute of Human Genetics. “33 of them were previously unknown.” The hits thus also provide clues to new therapeutic approaches. For example, the genes located in the identified regions often contain building instructions for so-called ion channels. These are essential for generating electrical pulses in the brain, the action potentials. The study draws particular attention to calcium channels. “They seem to be involved in the development of the disease,” Forstner explains. “There are drugs that affect the function of these channels, but so far they have only been approved for the treatment of other diseases. Maybe they could also be an option for bipolar disorder therapy.”

Smoking a possible risk factor

The genetic data also makes it easier to differentiate between different forms of the disease. Because there is more than one kind of bipolar disorder: The symptoms and courses of the disease can differ greatly. “We expect there to be different subtypes of the disease, each of which may also require slightly different treatment,” Forstner says. “We were for instance able to show that a form of bipolar disorder that is often very severe, called type I, is more strongly related to schizophrenia at the genetic level. In contrast, a somewhat “milder” variant – type II – appears to be more related to depression.”

The researchers also compared their findings with the results of studies that search for the genetic basis of certain behaviors. In the process, they came across interesting links: For example, smoking appears to significantly increase the risk of bipolar disorder. In the case of problematic alcohol consumption, however, the analyses suggest a bidirectional relationship: People with a predisposition to bipolar disorder drink more often; conversely, this behavior also appears to increase their likelihood of developing the disorder. “However, we advise caution in interpreting these findings,” Forstner explains. “The demonstrated associations between certain behaviors and bipolar disorder first need to be examined in further, large studies.”

The results were only possible thanks to the collaboration of around 320 researchers in an international consortium (Psychiatric Genomics Consortium). In addition to the researchers from Bonn, participants in the analyses also included a German-Swiss network with the Central Institute of Mental Health in Mannheim (Prof. Dr. Marcella Rietschel), the University Hospital of Munich (LMU, Prof. Dr. Thomas G. Schulze) and the University Hospital Basel (Prof. Dr. Sven Cichon). Prof. Nöthen is a member of the Transdisciplinary Research Area “Life and Health” at the University of Bonn as well as a member of the ImmunoSensation² Cluster of Excellence.

Funding:

The study was sponsored by the U.S. National Institute of Mental Health and the National Institute of Health, as well as numerous other institutions. In Germany, the project received funding from the DFG, the BMBF and the Dr. Lisa Oehler Foundation, among others.

Featured image: Prof. Dr. Markus M. Nöthen (left) – and Jun.-Prof. Dr. Andreas Forstner (right) from the Institute of Human Genetics at the University Hospital Bonn.© Andreas Stein/UKB


Publication: Niamh Mullins, Andreas J. Forstner et al.: Genome-wide association study of more than 40,000 bipolar disorder cases provides new insights into the underlying biology. Nature Genetics, DOI: 10.1038/s41588-021-00857-4


Provided by University of Bonn

Coral on the Red List of Endangered Species (Botany)

Data from extinct species helps to improve the assessment of extinction risk

The traits of coral species that have become extinct during the last few million years do not match those of coral species deemed at risk of extinction today. In a recently published article in the journal ‘Global Ecology and Biogeography’, a research team at FAU is therefore proposing that the International Union for Conservation of Nature (IUCN) revises its Red List of Threatened Species for coral.

The list categorises around a third of all 845 coral species that build reefs as endangered. The Red Lists published by the IUCN are considered extremely reliable as they are compiled by leading experts who regularly investigate how species populations have developed over the course of the last few years and decades. In conjunction with other factors such as conservation efforts or foreseeable influences such as climate change, these figures reliably predict the risk posed to a species in the future. ‘Unfortunately, it is extremely difficult to identify such trends for coral populations using the data currently available,’ explains Prof. Dr. Wolfgang Kießling,

Nussaïbah Raja Schoob at the Chair of Palaeoenvironmental Research (Prof. Kießling) at FAU therefore used an alternative method to investigate the extinction risk in reef coral in a collaborative project involving teams from the University of Queensland, Australia, and the University of Iowa in the USA. Schoob, who is a geoscientist, first investigated which traits the coral species on the Red List have in common. Climate change plays a significant role in the risk to this group. A similar phenomenon occurred during the last five million years when a land bridge formed between North and South America, which permanently shut down a strong ocean current from the Pacific into the Caribbean. This caused considerable changes to extremely important characteristics in the seawater such as temperature and salt content. At this time,18 species of coral disappeared from the Caribbean, and six of these species even became extinct. ‘We wanted to know which traits make coral species particularly sensitive to such significant changes and which traits improve their resilience,’ explains Nussaïbah Raja Schoob.

Schoob investigated a series of parameters such as the greatest water depth at which coral is found, the temperatures their larvae tolerate, how fast coral grows and which types of algae coral form symbiotic relationships with. Using machine learning, computer programmes identified similarities in the species that disappeared from the Caribbean in the past as well as in those which survived. Artificial intelligence was then used to identify the shared traits of the coral species categorised as endangered by the IUCN. Only 18 percent of the species on the Red List matched the results of the machine learning study based on palaeoenvironmental data.

‘These results contradicted all our expectations and we were therefore very puzzled by them,’ remembers Wolfgang Kießling. The researchers reviewed their findings to identify what had caused this discrepancy. It was unlikely that data from the coral populations of the past millions of years in the Caribbean had caused the unexpected findings. ‘This data is based on facts that we can observe and measure,’ explains Wolfgang Kießling. The scientists began to wonder if the problem was related to the Red Lists data.

This is where Nussaïbah Raja Schoob made a significant finding. The established and very successful system used by the IUCN to predict the risk to future populations of a species based on its population dynamics quickly reached its limits when examining reef-building coral. ‘There is hardly any data about population dynamics,’ explains Nussaïbah Raja Schoob. The IUCN had to adjust its methods and assessed the risk of extinction according to the changes in the surface area covered by coral reefs. ‘Even though this data is very important for the protection of coral reefs, which play an extremely important role for marine life they simply do not provide enough information about the risk to individual species for a very simple reason: Coral can also grow outside a reef directly on the sea floor, and this is quite common,’ explains Wolfgang Kießling. This means that there are usually still a few billion individuals of the species categorised as endangered, growing scattered on the ocean floor, which cannot simply just die off there simultaneously.

‘Our results show how important data from species that became extinct a long time ago is for assessing the risk for species that are alive today,’ explains Nussaïbah Raja Schoob. These palaeontological findings are a valuable source of data for developing the IUCN methods. Even if this means that the risk status of some coral species could be reduced, the study gives anything but the all-clear. ‘Coral reefs still continue to disappear, and with them a fantastic habitat that is very important for our oceans,’ says Wolfgang Kießling.

Original article: DOI: 10.1111/geb.13321

Featured image: How high is the extinction risk of coral in our oceans? FAU researcher Nussaïbah Raja Schoob used artificial intelligence to examine data from species that became extinct millions of years ago to assess this risk. (Image: Wolfgang Kießling)


Reference: Raja, NB, Lauchstedt, A, Pandolfi, JM, Kim, SW, Budd, AF, Kiessling, W. Morphological traits of reef corals predict extinction risk but not conservation status. Global Ecol Biogeogr. 2021; 00: 1– 12. https://doi.org/10.1111/geb.13321


Provided by FAU