In September 2023, employees of the Institute of Ecology and Evolution of the Russian Academy of Sciences, Academician of RAS V.V. Rozhnov and senior researcher A.A. Yachmennikov visited the People's Republic of China (Harbin), where they discussed the prospects for cooperation between the IEE RAS, which has existed since 2016, with the Institute of Natural Resources and Ecology of the Academy of Sciences of Heilongjiang Province. The negotiators discussed further scientific work and joint plans. At the reporting scientific conference on September 19, V.V. Rozhnov and A.A. Yachmennikov discussed with their Chinese colleagues the results of international cooperation obtained for the period 2017-2023. The conference presented materials published on the results of research that continues the ideology of the work being carried out in Russia. Restoration of the Amur Tiger (Panthera tigris altaica) Population in the Northwest of Its Distribution Area; Is the Lesser Khingan Suitable for the Amur Tiger Restoration? Perspectives with the Current State of the Habitat and Prey Base; The Structure of Potential Amur Tiger (Panthera tigris altaica) Habitats and Evaluation of Its Prey in Taipingou National Reserve (China) Based on Remote Sensing Data; Potential habitat suitability assessment of Amur tiger(Panthera tigris altaica) in Lesser Khingan Mountains based on MaxEnt model. In addition, employees of the IEE RAS took part in a round table within the framework of a scientific session devoted to the topic of conservation and restoration of populations of large cats (Amur tiger, Far Eastern leopard) in the territory of the People's Republic of China - Academic seminar on conservation and restoration of tiger and leopard population. At the official international level, the necessary documents were agreed upon confirming the extension of cooperation between the IEE RAS and the Institute of Natural Resources and Ecology of the Academy of Sciences of Heilongjiang Province, the text of the Memorandum confirming the extension of the agreement on the Joint Sino-Russian Innovative Research Center of Ecology (Ecology Center) was finalized and agreed upon in Russian and Chinese languages, the document was prepared for signing by the representatives of the Russian and Chinese Institutes. The Memorandum of the Sixth Joint Meeting of the Ecology Center in China was also signed. After the completion of official events, the Russian-Chinese team began implementing the next stage of the joint program - research devoted to the development of a system for distributing eco-products necessary for restoring the ecological metastructure of Heilongjiang Province. The structure of key core zones and corridors will unite remaining mammal habitats into a single functioning system and will restore the exchange of biological information between fragmented habitat areas. Field work took place on the territory of the Lesser Khingan mountain system (districts of the cities of Yichun, Hegang, Zhinshantong). The purpose of the field work was to verify on the ground a methodology for assessing the suitability of animals for crossing - both representatives of the food supply of tigers and leopards, and rare species of large cats. Roads of different categories (highway, regional road, small roads) were studied at their intersections with previously calculated environmental corridors. According to the scheme previously prepared by Ivan Kotlov, the first 30 points of intersection of roads and ecological corridors were worked out and provided with descriptions of factors limiting the settlement and movement of animals. Engineering solutions are also in development.

Fig.1: A baby Mongolian hamster during an experiment on recording ultrasounds at the Chernogolovka biological station, photograph by Rutovskaya M.V. Scientists from the Institute of Ecology and Evolution of the Russian Academy of Sciences, as well as M.V. Lomonosov Moscow State University found that the calls of 4-5 day old Mongolian hamster Allocricetulus curtatus cubs found outside the nest have the most complex acoustic structure among all the studied rodent species. The cubs produced both audible sounds and ultrasonic signals which can only be detected using special software that displays a spectrogram of the cry. The call recording test lasted 2 minutes, after which the pup was measured and weighed. Three independent fundamental frequencies were found in the calls, indicating that when producing them, the pups used not only the vocal cords, but also other sources that cause turbulence in the vocal tract. In addition, the cubs also produced purely noise calls, consisting entirely of acoustic chaos. Based on the presence of the three fundamental frequencies and their combinations, as well as chaos, all calls of the pups were classified into six different categories: (low-frequency tonal, low-frequency with chaos, high-frequency tonal, super-high-frequency tonal, calls with two high fundamental frequencies, high-frequency with chaos). For each of these categories, scientists assessed the relative occurrence, as well as the relationship with the body size of the cubs. Comparison of the obtained data with similar data on the young of other species shows that such high complexity of calls is unusual for rodents. It suggests that the Mongolian hamster, compared to the house mouse strains currently used as models of childhood autism, may show more noticeable and significant responses in medical tests for the effects of the medicine. Since autism causes a decrease in the complexity of vocalizations, this species can be recommended as a potential biological model for studying early-onset autism in humans. Fig.2: Spectrogram illustrating the variability of the acoustic signatures of the ultrasonic isolation calls of infant Mongolian hamsters based on the occurrence and interaction of three different fundamental frequencies and acoustic chaos. Fig.3:Plot illustrating the results of discriminant analysis for differences in sounds containing one of three independent fundamental frequencies in the calls of isolated Mongolian hamster pups. The results of the study were published in the journal Current Zoology: Rutovskaya M.V., Volodin I.A., Feoktistova N.Y., Surov A.V., Gureeva A.V., Volodina E.V. Acoustic complexity of pup isolation calls in Mongolian hamsters: 3-frequency phenomena and chaos. Current Zoology, 2023, zoad036.

Candidate of Biological Sciences, researcher at the Center for Bird Ringing, A.N. Severtsov Institute of Ecology and Evolution RAS Sofia Rosenfeld worked in the Nizhnekolymsk region. She was helped by Georgy Kirtaev, who pilots a small amphibious aircraft. Sofya Borisovna gave an interview to Kolymskaya Pravda about the process of her work. — Sofya Borisovna, you have now returned from work on the eastern coast of Chukotka, tell us about your work? — This year we worked together with the spoon-billed sandpiper project, already 22 years old as of this year. The work took place in southern Chukotka, near the village of Meinypilgyno. There are lakes there and you can say this is a unique place, there are also spoon-billed waders there, there are goose spots and we have always worked on them, but I would like to make a comprehensive expedition. This year we worked to survey this territory almost to the border with Kamchatka. First of all, our attention was focused on the white goose. This species of geese is listed in the Red Book and has always been rare, and only in isolated areas of Chukotka was it found in any significant quantities. Why is it interesting? Almost 80% of this type of geese that we see comes to us from Alaska to molt. And it has always been important for scientists in Alaska to know how many white-necked geese fly there to molt, and how many to breed. We have now almost completed a joint project on three species of eiders and the white-necked goose. — We carried out many flights to search for new groups of spoon-billed sandpiper. This unique bird is included in the Top 10 most endangered birds in the world. According to the most optimistic estimates, there are no more than 400 pairs left, and maybe less. They nest only in southern Chukotka. There is a known grouping of them near the village of Meinypilgyno, but it is very important to find other places. We use the plane to explore other areas that are not always accessible by boat or all-terrain vehicle. In general, the logistics here are very complex. And in one of these places we found nesting spoon-billed sandpipers and even marked them with rings. The work went well. But we worked not only in southern Chukotka, but also in the Lower Anadyr Lowland. It is also an interesting goose and duck area. In Soviet times, ornithologists from the Magadan Institute worked there a lot, and it will be interesting to compare the data from those years and modern ones. Work on eiders was planned in the Chaunsky district, but unfortunately it didn’t work out - the group was stopped in Anadyr due to the weather. But I hope that next year we will carry out work there. — Don’t predators hunt these unique birds? — There are a lot of bears there, just a huge number, but they are focused either on discarded dead marine mammals or on fish. — So they don’t pay much attention to birds? — Well, why should they? It’s difficult to catch them, the birds are small, it’s easier to catch a fish or find a dead walrus and eat it. — On the way from Chersky you plan to visit Bolshaya and Malaya Kuropatochya. Will you work on geese there too? — In this area we are most interested in the lesser white-fronted goose. This is also a rather rare species, listed in the Red Book. These birds spend the winter in China, where they were tagged with transmitters, and all the signals that were received from them came from the area of Malaya Kuropatochyaya and slightly from Bolshaya Kuropatochyaya. It is necessary to see what is happening there and how many birds there are. Apparently in this area there is a molting center for this rare species. It turns out that this work is being carried out jointly with our Chinese colleagues. — In Chersky you met with the management and inspectors of the Bear Islands Nature Reserve. Do you have any mutual interest? — In fact, the reserve inspectors have very interesting observations on the mainland – Agafonovo and the surrounding area. A white goose nests there, there is a colony of black geese, and it’s also interesting that they found Siberian Cranes on the territory of the reserve. These are very rare species and this information is very valuable. There is interest in this regard. I would like to note that the Bear Islands inspectors are very competent specialists. No matter how many inspectors I have seen at other reserves, there were none so competent. They know the area and birds well, and feel at home in the tundra. These are really working, thinking people and it’s very nice. As for the Siberian Cranes, we know for sure that their numbers are increasing, we know from censuses in China. If the number grows, then the birds must spread somewhere throughout their range, especially since they are a territorial bird, they need large individual areas. Maybe this is the reason that they appeared in Lower Kolyma. Or another option is that no one has ever looked there before… We worked there in 2020 and 2022 and saw Siberian Cranes. But we didn’t work specifically on them, we just noted their presence. — You have been engaged in research work in the Arctic regions for many years, sometimes flying the same routes. In your opinion, are climate changes happening and are they affecting birds? — I haven’t been alive long enough to say that. Long-term series of data and observation are needed. What we can say, and this can be seen with the naked eye, is that autumn has become warmer. I won’t talk about summer and spring; there have been both cold and warm seasons before. But autumn has definitely become warmer and this is very good for geese. The more geese sit in the tundra, the greater the chance that the chicks will have time to get stronger and become more prepared for long flights for the winter. That is, there are benefits for geese, but I think that warming is also good for cranes. — You are now completing the summer stage of field work. How will the information received be processed in winter? — I hope not in winter, but we’ll start in the fall. We have a photo bank, i.e. during flights we photograph all the birds. Next, we will identify them, count them, enter them into an open database, and anyone can view them. Perhaps an article will be written, but first we need to see what happened and think about it. — Good luck and see you in Lower Kolyma next year! Related materials: Kolyma Pravda: “Scientists from Moscow are studying Arctic birds”

A team of Russian parasitologists and theriologists studied the species diversity and distribution of helminths of wild and semi-wild reindeer (Rangifer tarandus), musk ox (Ovibos moschatus) and bighorn sheep (Ovis nivicola) in the Russian Arctic. The helminth fauna of reindeer and bighorn sheep was previously studied about 60 years ago. Moreover, the deer were mostly domestic. And, of course, in those years molecular phylogenetic methods had not yet been developed. The musk ox was introduced in the 70s from North America, and its helminths were not studied in Russia at all. Considering the active development of the Arctic coupled with climate change, it was very important to obtain reference data for the current moment. Researchers collected 519 samples of ruminant feces in the north of the Palaearctic: in the Arkhangelsk and Murmansk regions (including the Novaya Zemlya archipelago), in the republics of Karelia and Sakha, on the Kola, Yamal, Taimyr and Chukotka peninsulas, on the Bering, Wrangel and Spitsbergen islands (Norway). The latter was included for comparison on the basis of the Spitsbergen Treaty, which granted Russia the right to exploit natural resources and the actual presence of our country on the archipelago. The Center for Parasitology of the Institute of Ecology and Evolution of the Russian Academy of Sciences conducted a helminth-coprological study to identify eggs and larvae of helminths of the digestive, respiratory, nervous and muscular systems. Parasites were identified based on morphological and morphometric data and analysis of nucleotide sequences. The extent and intensity of the invasion were established. Two genera of trematodes (Paramphistomum and Dicrocoelium), one genus of cestodes (Moniezia) and various nematodes were found in reindeer: small gastrointestinal nematodes, Marshallagia sp., Nematodirus spp. (three different morphotypes), Nematodirella sp. (including N. longissimespiculata), Skrjabinema tarandi, Trichuris sp., Capillaria spp., Ascaris mosgovoyi, Dictyocaulus sp., Elaphostrongylus rangiferi, Orthostrongylus macrotis and Varestrongylus eleguneniensis. A photograph of an A. mosgovoyi egg is presented for the first time. V. eleguneniensis has not previously been found in the Palearctic. This is also the first report of O. macrotis in reindeer. No trematodes were found in muskox, but one genus of cestodes (Moniezia) and various nematodes (small gastrointestinal nematodes, Nematodirus sp., Nematodirella sp., Trichuris sp., larvae from the family Protostrongylidae) were found. No trematodes were found in bighorn sheep, but one genus of cestodes (Moniezia) and various nematodes (small gastrointestinal nematodes, Marshallagia sp., Nematodirus sp., Trichuris sp., capillary nematode and various morphotypes of Protostrongylus) were found. Capillary-like nematodes have not previously been found in bighorn sheep. With the exception of one case with a deer from a private zoo, in all examined ruminants the intensity of invasion was low, which indicates a satisfactory immune status of the animals. The habitats of bighorn sheep are quite isolated, but introduced musk oxen are in sympatry with reindeer. The authors consider introduced species as a possible reason for the discovery of North American parasites in native reindeer. In addition to true parasites, false (spurious) and pseudoparasites were found in feces. Among them were bdelloid rotifers at various stages of development. In dried fecal samples, they came to life after adding water. Rotifers may have contaminated feces after excretion (as the material was often picked up from the ground). Or they were accidentally ingested and managed to survive inside the ruminants. To the authors' knowledge, Arctic ruminants have never been implicated as hosts of rotifers. Given that reindeer travel long distances every day, they may play an important role in the spread of rotifers. O. A. Loginova, S. B. Rosenfeld, T. P. Sipko and S. E. Spiridonov participated in the work from the IEE RAS. The article was published in a special issue of the journal “Diversity” (Q1) “Biodiversity of Parasites in Vertebrates in the Wildlife” in open access mode. https://www.mdpi.com/1424-2818/15/5/672 Loginova, Olga A., Sofya B. Rozenfeld, Taras P. Sipko, Ivan A. Mizin, Danila V. Panchenko, Kasim A. Laishev, Mikhail G. Bondar, Leonid A. Kolpashchikov, Aleksandr R. Gruzdev, Pavel S. Kulemeev, Dennis I. Litovka, Mariia N. Semerikova, Viktor N. Mamontov, Evgeniy G. Mamaev, and Sergei E. Spiridonov. 2023. "Diversity and Distribution of Helminths in Wild Ruminants of the Russian Arctic: Reindeer (Rangifer tarandus), Muskoxen (Ovibos moschatus), and Snow Sheep (Ovis nivicola)" Diversity 15, no. 5: 672. https://doi.org/10.3390/d15050672 Related materials: Ministry of Education and Science: "Scientists have identified new parasites in ruminants in the Arctic and Spitsbergen" RAS: "New parasites in ruminants in the Arctic and Spitsbergen" Comfort-sr: "Scientists have identified new parasites in ruminants in the Arctic and Spitsbergen" Ferra.ru: “Russian scientists have found worms unknown to science among Arctic ruminants” Glas Naroda: "New parasites found in ruminants in the Russian Arctic and Spitsbergen" Rambler: "Scientists from Russia have found worms unknown to science among Arctic ruminants" Arguments and facts: “Unusual types of worms were found in reindeer” PC-problems: "Scientists from Russia found worms unknown to science among Arctic ruminants" Science and Life: “The parasites of Russian reindeer have been counted” Club-TM: “Scientists from Russia found worms unknown to science among Arctic ruminants” Day-inews: “Russian scientists have found worms unknown to science among Arctic ruminants” Vesti1: "Unusual types of worms were found in reindeer" Tnaneve.spb: “Scientists from Russia found worms unknown to science among Arctic ruminants”

Fig.1. Features of the structure of the skull and teeth in the entelodont Archaeotherium mortoni (D), the anthracotherium Paenanthracotherium bergeri (E) and several modern mammals: the brown bear (A), the wild boar (B) and the pygmy hippopotamus (C). Image from the article discussed In a recent study, specialists from Russia and Spain for the first time studied the nutritional characteristics of representatives of two families of primitive fossil artiodactyls — anthracotheriums and entelodonts. The material for the study was the teeth of ungulates from the Quercy locality (southern France) and had been kept in the collections of the V.I. Vernadsky Geological Museum for more than a century. The age of the studied fossils corresponds to the Oligocene era (33.9-23 million years ago). Representatives of the entelodontidae family are known in popular culture as “hell pigs”. They were characterized by impressive sizes, the largest representatives of the family reached the size of a bull, and a large skull up to 90 cm in length. There were numerous bony outgrowths and tubercles on the skull and lower jaw of entelodonts. These ungulates retained a full set of teeth characteristic of primitive placental mammals (three incisors, a canine, four premolars and three molars in each half of the upper and lower jaw), their incisors and canines were very large, the premolars were triangular in side view, the molars the teeth were quite small, low-crowned, and bunodont (i.e., tuberculate; Fig. 1). The skull and lower jaw of entelodonts had a number of features characteristic of carnivores: a powerful sagittal crest, large temporal fenestrae for masticatory muscles, the position of the articular tubercle on the lower jaw at the level of the dentition, and triangular premolar teeth when viewed from the side. The presence of these features formed the basis for reconstructions of entelodonts as scavengers, capable of chewing bones like hyenas, or even active predators. Anthracotheriidae are a family of large pig-like mammals that lived in North Africa, Eurasia, and North and Central America from the late Eocene to the Miocene. Modern research shows that it is from the African branch of Anthracotherium that modern hippopotamuses originate, which are thus recent representatives of the family. The appearance of these animals had similar features to both pigs and hippos. These were medium-sized and large-sized ungulates with very short legs, their front limb was five-toed, the back was four-toed, and the lateral toes were well developed. Anthracotheriums had a large head with a long and narrow facial part of the skull and a full set of teeth. Their incisors were large and similar to the incisors of pigs (Fig. 1). The cheek teeth were low-crowned and often bunodont, but in some advanced species they became larger, almost square when viewed on the chewing surface, and selenodont (that is, having crescent-shaped cutting enamel ridges). To study in detail the feeding habits of fossil ungulates, researchers used the method of analyzing microwear of tooth enamel. For a comparative analysis, 10 categories of animals were identified among modern ungulates and carnivores, occupying different ecological niches and specializing in a variety of food sources. These are (1) omnivores (pig, wild boar and brown bear), (2) specialized meat eaters (cheetah and lion), (3) meat-eating and bone-crunching (hyenas), (4) predators with a wide variety of food (fox), ( 5) mixed carnivory/fruitivory (common genet and palm civet), (6) piscivorous (otter), (7) folivorous (elk, giraffe, etc.), (8) frugivorous/folivorous (various duikers), (9) herbivorous (buffalo, zebra, etc.), (10) herbivores/semi-aquatic (common hippopotamus). As a result of the analysis of the microwear pattern of the cheek teeth, it was shown that the large European Entelodon magnus was an omnivorous mammal, and the wear pattern of the enamel of its teeth was almost identical to the modern wild boar (Sus scrofa) and somewhat different from the brown bear (Ursus arctos). The diet of modern pigs is extremely diverse and varies greatly depending on the habitat and season of the year. Modern pigs feed on fresh green grasses, succulents, legumes, fruits, acorns, seeds, roots, bulbs, bark, fungi, invertebrates (worms, molluscs, beetles), fish, frogs, reptiles, small birds, rodents, newborn or injured mammals, and corpses, as well as eggs of birds and reptiles nesting on the ground. Microwear of tooth enamel indicates that similar plasticity in nutrition was characteristic of “hell pigs”. Unlike entelodons, the studied anthracotheriums turned out to be specialized herbivores. Half of the studied individuals of the genus Anthracotherium were characterized by a folivorous diet, a quarter were folivorous + frugivorous, and another quarter were herbivorous. This dietary diversity could be due to seasonal variations in nutrition. The data obtained as a result of the study allowed the authors to make assumptions about the nature of digestion in representatives of the two studied families of ancient and primitive pig-like artiodactyls. It is likely that entelodonts, with their simply constructed, pressing, tuberculate teeth and omnivorous diet, were characterized by the digestion of food in a simple stomach, just as it occurs in modern pigs. The deviation from omnivory towards leaf-and herbivory of Huanthracotheriums corresponds to the increased (compared to pigs and entelodonts) complexity of the structure of the chewing surface of their molars, on which cutting enamel ridges appear. It is likely that representatives of the genus Anthracotherium were characterized by cellulose fermentation in a complex stomach, just like modern hippopotamuses descended from Anthracotherium. Source: Florent Rivals, RuslanI.Belyaev, VeraB.Basova, NatalyaE.Prilepskaya. Hogs, hippos or bears? Paleodiet of European Oligocene anthracotheres and entelodonts// Palaeogeography, Palaeoclimatology, Palaeoecology. 2023. V.611, 111363. https://doi.org/10.1016/j.palaeo.2022.111363.

Fig.1: Thermokarst lakes in the Lena River delta (above), hydrobiologists at a rest stop (below).Author of photographs: Sadchikov I.P. Analysis of the variability of biological communities inhabiting thermokarst lakes is important for assessing the degree of transformation of the Arctic ecosystem under the influence of climate change. When permafrost thaws, a gradual change in size occurs, and with it, the hydrology of tundra reservoirs. Environmental conditions changing during these processes have a significant impact on aquatic biota. The question arises: what is the variability of communities of different ecological and size groups of organisms during the development of a thermokarst reservoir? Scientists from the A.N. Severtsov Institute of Ecology and Evolution RAS (Moscow) together with colleagues from M.V. Lomonosov Moscow State University performed a comprehensive analysis of the communities of bottom and planktonic invertebrates in lakes of the Lena River delta. In three hydrological types of thermokarst reservoirs, the fauna of microbenthos (testate amoebas), zooplankton and meiobenthos (copepods and cladocerans), as well as macrozoobenthos (oligochaete worms, mollusks, amphipods and insect larvae) were studied. The consistent variability in the structure of aquatic communities during the development of a thermokarst reservoir from a small polygonal pond to a large deep lake is described. It has been shown that the number of species of multicellular organisms is higher in lakes than in polygonal ponds. This is due to freezing to the bottom of small reservoirs in winter, which leads to the death of many organisms. The species richness of testate amoebae, which form persistent resting stages, is, on the contrary, higher in polygonal ponds overgrown with mosses and sedges. This fact is explained by the fact that the group is confined to deposits of plant remains. During the formation of communities of small organisms (testate amoebas and microcrustaceans), with life cycles lasting several times less than the summer season, the temperature factor was significant, varying over time intervals of weeks and months, as well as the acidity of the environment, changing interannually. For insect larvae that predominate on the bottom, with a development cycle of up to six months, all key factors varied over the range of a year or more. Global climate change primarily affects organisms that subtly respond to short-term measurements of environmental conditions. Thus, the first signal of changes in the ecosystem of Arctic lakes will be restructuring of communities of testate amoebae and microcrustaceans. Since most species of testate amoebae have wide ranges, it will be easier to notice changes in the composition of microcrustaceans that are more narrowly distributed. It is likely that copepods and cladocerans can be one of the main indicator groups when assessing the transformation of an ecosystem under a changing climate. The research was supported by the Russian Science Foundation grant No. 23-24-00054. Chertoprud E.S., Novichkova A.A., Tsyganov A.N., Vorobjeva L.V., Esaulov A.S., Krylenko S.V., Mazei Y.A. 2023. Species diversity and driving factors of benthic and zooplanktonic assemblages at different stages of thermokarst lake development: a case study in the Lena River delta (Middle Siberia)// Diversity. 15(4), 511. https://doi.org/10.3390/d15040511 Related materials: Ministry of Education and Science: “Biologists have discovered animals whose behavior mayserve as a signal of climate change”

A series of experiments aimed at studying the symbiont fauna of corals of the genus Pocillopora showed how the size, health, age and even growth conditions of the host colony affect the animals living on it. The study was carried out at the Dam Bai Research Station (Vietnam), a region that is home to the richest obligate coral symbiont fauna in the world. Employees of the Laboratory of Morphology and Ecology of Marine Invertebrates of the Institute of Ecology and Evolution of the Russian Academy of Sciences discovered that an increase in the size and density of host colonies causes both the enrichment of the symbiont fauna with new species and an increase in the number of symbionts themselves. Moreover, differences were shown in the response of different groups of symbionts to changes in the same properties of the host. Thus, as the planting density of hosts increased, the diversity and abundance of obligate symbionts increased, while these indicators of facultative symbionts, on the contrary, decreased. According to the working hypothesis, an increase in the number of obligate symbionts – “specialists” – increases competition with less adapted facultative symbionts – “opportunists”, which leads to a decrease in the number of the latter. Interestingly, the deterioration of hosts caused by seasonal bleaching (bleaching due to the release of symbiotic algae) had no noticeable effect on either obligate or facultative symbionts. Among other questions that the laboratory staff answered, one stands out: how does the composition and richness of the fauna of coral symbionts differ between those grown in a nursery and grown in natural conditions? It turned out that the diversity of symbionts in the nurseries was comparable or even higher than that on a natural reef located nearby. However, the species richness and density of symbionts on naturally occurring host corals was still higher than on corals grown in nurseries. The findings show that multiple coral farms can help restore not only damaged coral reefs, but also the specialized species of invertebrates and fish that live on the surface and inside coral colonies that need protection. Moreover, it is now clear under what conditions corals should be grown in nurseries to ensure the greatest richness and diversity of symbiont fauna. The research was carried out with the support of the Russian Science Foundation (project No. 22–24-00836). Detailed results of the work are presented in publications: Britayev T.A., Petrochenko R.A., Burmistrova Y.A., Nguyen T.H., Lishchenko F.V. 2023. Density and Bleaching of Corals and Their Relationship to the Coral Symbiotic Community. Diversity 2023, 15, 456. https://doi.org/10.3390/d15030456 Q2 Britayev T.A., Zvonareva S.S., Lishchenko F.V., Deart Y.V. 2023. Symbiotic communities associated with nursery-reared and natural corals: are they similar? Frontiers in Marine Science, 10 (2023). https://doi.org/10.3389/fmars.2023.1221922 Q1

Fig.1. Variety of colors in experimental cichlids - Amatitlania nigrofasciata. 1–7 – adults melanistic elements, (a, p) – anterior and posterior stripes, LS – larval stripe. Cichlids are the largest family of vertebrates and have a wide variety of pigment patterns, making them a favorite among aquarium hobbyists. In addition to its contemplative value for humans, coloration is of utmost importance for the life activity and evolution of the cichlid fish themselves. However, information about the causes and mechanisms underlying the formation of its diversity is scattered and sporadic. Employees of our institute were able to show that one of the most important factors influencing the ontogenesis and evolution of the diversity of cichlid colors is the activity of the thyroid gland and the dynamics of the concentrations of thyroid hormones synthesized by the gland. This conclusion is based on results obtained from experimental work on two species of Neotropical cichlids (Amatitlania nigrofasciata and Cryptoheros spilurus). In particular, it was found that thyroid hormones have a direct effect on the temporal characteristics of ontogenesis of most pigment cell lines. Untimely changes in hormone concentrations (hyper- or hypothyroidism) often lead to irreversible consequences and the formation of coloration characteristic not of this species (Fig. 1), but of other species of phylogenetically close and distant Neotropical cichlids. Taken together with previously obtained data on the participation of thyroid hormones in the formation of phenotypic diversity of various groups of fish and amphibians, the results presented in this work provide important evidence of the key role of the hypothalamic-pituitary-thyroid axis in the evolution of vertebrates. The work was published in the oldest scientific international journal «Journal of Experimental Biology» (SJR Q1). Denis V. Prazdnikov and Fedor N. Shkil (2023). The role of thyroid hormones in development of coloration of two species of Neotropical cichlids. J. Exp. Biol. 226 (14), jeb245710. https://doi.org/10.1242/jeb.245710

Fig.1. Generalized and big-lipped sympatric forms of the african barb Speciation is a long-term process that extends far beyond the lifetime of the observer. When studying speciation, procedural reconstructions are required. The most suitable objects for studying speciation are parallel situations among closely related species that are at different stages of development. By studying and comparing such cases, it is possible to reconstruct the process of speciation from origin to the formation of new species. Fig.2. Material collection map A team of researchers from Russia (IEE RAS, IBVV RAS, Zoological Institute RAS), Germany and Japan studied an adaptive trait in fish - hypertrophied lips, also called rubber lips, using the example of African longhorned beetles. Typically, enlarged lips in fish are used for a rather specific method of feeding - sealing cracks in rocks, depressions between stones and sucking out the benthos hidden there. However, the feeding preferences of rubber-lipped longhorned beetles were unknown. Using methods of ecology and genomics, six populations of ray-finned fish Labeobarbus (Cyprinidae) from water bodies in East Africa (Ethiopia), in which this trait arose in parallel, were studied. The use of trophic methods (analysis of the composition of the food bolus and the ratio of stable isotopes of nitrogen and carbon) showed that despite the equally well-developed lips, only in half of the populations they were used for a specialized method of feeding (benthophagy) and sharing trophic resources with the generalized ancestral form, from which a rubber-lipped form occurred. Fig. 3. Division of trophic resources between sympatric pairs of lipped and generalized forms according to the analysis of stable isotopes d15N and d13C. According to genetic results (mtDNA analysis and genomic analysis), in only one of six cases the genetic divergence between the sympatric lipped and generalized forms reached the species level. Thus, a continuum of speciation has been discovered - from non-functional polymorphism through ecologically relevant polymorphism to divergent evolution (speciation). Fig.4. Genomic analysis (A - tree, population genetic structure; B - analysis of the main component) based on 15820 single nucleotide polymorphisms (SNPs). Lipped forms are marked on the tree in yellow, and in the space of the principal component s - outlined in yellow. The obtained results support the 'plasticity-first' evolutionary hypothesis, according to which phenotypic innovation first arises and then its ecological functionalization occurs. The work was published in the journal Ecology and Evolution by Wiley -https://onlinelibrary.wiley.com/doi/full/10.1002/ece3.10523 Levin, B., Komarova, A., Simonov, E., Tiunov, A., Levina, M., Golubtsov, A., F. Kondrashov, & Meyer, A. (2023). Speciation and repeated origins of hypertrophied lips in parallel adaptive radiations of cyprinid fish from East Africa.Ecology and Evolution,13(9), e10523. The study was supported by the Russian Science Foundation grant 19-14-00218.

Scientists from the A.N. Severtsov Institute of Ecology and Evolution of the Russian Academy of Sciences, as well as M.V. Lomonosov Moscow State University conducted a study of the acoustic parameters of the meows of feral adult domestic cats Felis silvestris catus kept in captivity during the breeding season. During the breeding season of domestic cats, both sexes dramatically increase their vocal activity. Loud meows can be used by animals to determine the gender of a potential partner and his individuality (in groups of more or less constant composition). However, to date there have been no studies that directly support these assumptions. Picture: Spectrogram illustrating individual and sex differences in the meows of adult domestic cats during the breeding season. Above: meowing of three males, below - three females. An audio file of these screams is available in the Supplementary material for the article. As a result of the analysis of the acoustic parameters of meows of 5 males and 6 females of adult domestic cats, it turned out that the percentage of correct assignment of meows to sex in discriminant analysis averaged 88.0%, and to an individual averaged 79.2%, which significantly exceeds the random level calculated with using a permutation test. Also, male meows were much lower in frequency, with a maximum fundamental frequency of 0.37 ± 0.05 kHz compared to 0.61 ± 0.16 kHz in females. Picture: Diagram illustrating individual and sex differences in the meows of adult domestic cats. Males are indicated in blue, females in red. (a) – differences in duration (in seconds), (b) – differences in the maximum values of the fundamental frequency (f0max, in kilohertz). Thus, the study showed that acoustic differences in the meows of adult domestic cats during the breeding season may encode information about the sex and identity of the animals calling. The results of the study were published in the journal Behaviour: Sedova L.M., Volodin I.A., Erofeeva M.N., Alekseeva G.S., Naidenko S.V., Volodina E.V., Meows of captive feral domestic cats (Felis silvestris catus) in the mating season: acoustic correlates of caller identity and sex. Behaviour. DOI: 10.1163/1568539X-bja10239 Related materials: Nauka.rf: "Meowing contains individual information about cats" Outpost Sevastopol: “The meowing of cats was studied at Moscow State University” RAS: "The meowing of domestic cats contains individual information about the animals" 7ooo.ru: “The meowing of cats was studied at Moscow State University” Rambler: "The meowing of cats was studied at Moscow State University"