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The Silurian thelodont Phlebolepis elegans Pander from Saaremaa, Estonia, is one of the most-often illustrated early vertebrates, yet its external morphology has remained poorly known and experts seldom agree about its probable body form. We examined hundreds of articulated specimens from the type locality (Himmiste Quarry) to reconstruct its morphological features. We found that a reconstruction published more than four decades ago by A. Ritchie was the best available till now. We disagreed mostly in that the mouth is not terminal, but subterminal, and there is a slight development of a rostrum dorsal to the mouth. The pectoral fin originates close behind the orbits, but is otherwise similar to Ritchie’s reconstruction. We also found the caudal fin to be much larger, more flexible and more symmetrical (though not perfectly symmetrical) than earlier reconstructions, with a large dorsal lobe and an even larger ventral lobe, and a fin web supported by slender ‘ray-like’ scale-covered lobes. The shape, number and location of the branchial openings are notably still not certainly known. Our preferred morphological features are represented by an artist’s restoration. With this revised understanding, future representations of Phlebolepis elegans can be based on more reliable information and its morphology can be compared more accurately with that of other early vertebrates.

Recent studies on the use of wild food plants have identified various reasons for their use and underlined their importance as an emergency food supply. This work analysed the content of narratives obtained as comments regarding the reasons for using or not using wild food plants mentioned during 48 semi-structured recorded interviews. The results show that past demand for the diversification of food experiences and taste was essential for the consumption of wild plants, while the present concern for the disappearance of wild food taxa familiar from childhood is one of the main reasons for decrease in their consumption. This indicates that people do not really feel that they need to use wild food plants anymore (except for the health benefits), and that they are concerned that their favourite plants are no longer available. The erosion of the practical use of wild food plants is also supported by the very small frequency in which the influence of teachings coming from outside the community was mentioned in discussions of both the past and present, and thus the loss of traditional uses is not really substituted by new uses acquired from elsewhere. Further research is needed to understand lay perceptions of the changes that have occurred in nature, society and the economy, in the context of their influence on the everyday use of wild food plants to appreciate the ways in which knowledge erosion takes place and to find means of retaining this basic knowledge within the society. [ABSTRACT FROM AUTHOR]

Glacial stratigraphy of the West Estonian Islands comprises three different diamicton units which are correlated event-stratigraphically to the Pandivere and Palivere ice advances of the most recent (Late Weichselian) glaciation and included into the Vörtsjärve Subformation according to Estonian stratigraphic nomenclature. A large number of till samples (1136) and drillcore sections (2500) were analysed in order to determine the genesis and composition of sediments from which the lithostratigraphical conclusions are derived. The two topmost diamictons are interpreted as genetic varieties of the Palivere Till – waterline melt-out and basal till. The Pandivere Till is the lowermost widespread till layer on the islands, which lies unconformably between the Palivere Till and carbonaceous bedrock. Lacustrine Köpu Sands separate the Palivere and Pandivere Tills in a few boreholes on the Köpu and Sörve Peninsulas. In deeply buried valleys on the Sörve Peninsula the Pandivere Till is underlain by lacustrine Viieristi Sands and greenish-grey compact till of unknown age. The correlatives of the Palivere and Pandivere Tills in southern Finland, south of Salpausselkä I (SSI), are thought to be the Espoo and Siuntio Tills, respectively.

The Silurian thelodont Phlebolepis elegans Pander from Saaremaa, Estonia, is one of the most-often illustrated early vertebrates, yet its external morphology has remained poorly known and experts seldom agree about its probable body form. We examined hundreds of articulated specimens from the type locality (Himmiste Quarry) to reconstruct its morphological features. We found that a reconstruction published more than four decades ago by A. Ritchie was the best available till now. We disagreed mostly in that the mouth is not terminal, but subterminal, and there is a slight development of a rostrum dorsal to the mouth. The pectoral fin originates close behind the orbits, but is otherwise similar to Ritchie's reconstruction. We also found the caudal fin to be much larger, more flexible and more symmetrical (though not perfectly symmetrical) than earlier reconstructions, with a large dorsal lobe and an even larger ventral lobe, and a fin web supported by slender 'ray-like' scale-covered lobes. The shape, number and location of the branchial openings are notably still not certainly known. Our preferred morphological features are represented by an artist's restoration. With this revised understanding, future representations of Phlebolepis elegans can be based on more reliable information and its morphology can be compared more accurately with that of other early vertebrates. [ABSTRACT FROM AUTHOR]

In-situ minor, trace and rare earth element (REE) compositions have been measured in conodonts from the lower Silurian Vesiku Bone Bed (Estonia), with the aim to visualize and to quantify conodont apatite elemental geochemistry, to evaluate compositional differences between conodont histologies, and to evaluate the use of conodont chemistry as a palaeobiological or palaeoenvironmental proxy. Tissue-selective analyses of minor, trace and rare earth element compositions of albid, hyaline, and basal tissues demonstrated significant chemical offsets among these histologies. The albid tissue had the lowest REE and trace element concentrations, suggesting crystallinity-determined better resilience to diagenetic alteration as documented in previous studies. Conversely, the basal tissue had highest concentrations of REEs and many trace elements, except for Sr that showed an opposite trend. The higher concentrations in albid and hyaline tissues supports the in-vivo Sr incorporation by conodont crown. Nonetheless , the obtained SN-normalized REE patterns were uniform through all the analyzed conodont taxa and different tissues, implying common diagenetic history. Absence of a Ce anomaly, and defined negative Eu anomaly indicate reducing conditions during early burial. These results validate current interpretations of the palaeoenvironmental conditions during the deposition of Vesiku Bone Bed and bolsters the use of REEs in Palaeozoic marine vertebrates as an important palaeoenvironmental proxy. • REE from conodont apatite reflect palaeoenvironmental conditions of Vesiku bone bed. • Conodont element histologies show differences in REE concentrations. • Inter-tissue Sr compositions supports in-vivo Sr incorporation by conodont crown. [ABSTRACT FROM AUTHOR]