№ 1 (2023)

The paradox of seismicity has long been known: the mechanism of ordinary fragile breakings cannot support realization of the earthquakes at depths of more than a few dozen kilometers. However, earthquakes occur much deeper. Various models that linked the occurrence of earthquakes with the release of fluid and phase transformations in the downgoing plates have been proposed to explain such events. However, the changes in the seismic mechanisms of earthquakes should be accompanied by the depth-associated changes in the focus parameters, whereas such changes have not been found until recently. The lack of such confirmation of the model suggestions prevents the finding of a solution for the mystery of deep-focus earthquakes. Recently, such changes that fit well with theoretically expected have been revealed. Thus, the almost century-old riddle of the nature of deep earthquakes has found its answer.

The main issue of the species problem is the following: do species really exist or is it just an abstract taxonomic category invented by taxonomists to describe biological diversity? The dilemma “either species without evolution or evolution without species” can be solved by logically substantiating that there should be only few (or no) transitional forms between subspecies and species. In the terms of the biological concept of a species, the reinforcement hypothesis serves as such justification: in the hybrid zone, natural selection facilitates mechanisms of ethological isolation, i.e. secondary contact leads to an acceleration of the process of speciation. The key point of this hypothesis is the statement about the reduced fitness of hybrids resulted from the destruction of the co-adapted gene complexes of parental forms, the formation mechanism of which is described by the Dobzhansky—Muller model. To evaluate the effectiveness of reproductive isolation mechanisms and the viability of hybrids, I conducted a long-term monitoring of the hybrid population of the yellowhammer and the pine bunting in Altai. It turned out that the hybrids are actually characterized by the shorter life span than the birds with the parental type of phenotype. It confirms the Dobzhansky—Muller model, although the reinforcement hypothesis does not find its confirmation in this case.

The article present general information about brachiopods, as well as data on new findings of the craniids Danocrania tuberculata and D.polonica from the Danian of the Mountainous Crimea.

A set of old postcards dated to the beginning of the XX century with hunting scenes was found in an antique shop in Murmansk. These cards are regarded as a historical document, an interesting evidence of a bygone era. The postmarks accurately determine the year of mailing and receiving the correspondence, as well as the address of the addressee. Careful reading of the unpretentious text and brining the obtained information together lead to the new knowledge about the well-known and slightly open the forgotten pages of the life of people in the Far East in Russian Empire.

Биология / История науки. И.Я.Павлинов. ПРОБЛЕМА ВИДА В БИОЛОГИИ: ИСТОКИ И СОВРЕМЕННОСТЬ. М.: Товарищество научных изданий КМК, 2023. 216 с. Зоология / Музееведение. С.Н.Баккал. ОРНИТОЛОГИЧЕСКАЯ КОЛЛЕКЦИЯ ЗООЛОГИЧЕСКОГО МУЗЕЯ ИМПЕРАТОРСКОЙ АКАДЕМИИ НАУК: ОЧЕРКИ ИСТОРИИ. М.: Товарищество научных изданий МКМ, 2022. 415 с.