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3D morphology of post mortem acrothoracican borings in Famennian heterocorals : a morphological diversification or a continuum ichnospecies?

Dworczak Patrycja G., Jarochowska Emilia, López Correa Matthias, Berkowski Błażej

Annales Societatis Geologorum Poloniae

2022

Vol. 92, No. 3

233--252

Barnacle borings were found in six heterocoral skeletons. They are present as small (up to 2.9 mm long), slender, pouch-shaped borings with tapering, slit-like openings. The investigated borings were made by acrothoracican cirripedes, which mostly do not have a shell and bore into hard substrates to protect their “naked” bodies. The first occurrence of borings in skeletons of the heterocoral Oligophylloides Różkowska, 1969 from the Upper Devonian Tafilalt Platform was reported recently by Weyer in 2016. Here, the authors present the results of a detailed study of heterocoral remains with numerous acrothoracican borings from Jebel Bou Ifarherioun (Famennian, Anti-Atlas, Morocco). The borings were found on the basal part but also on broken branches and stems of the heterocoral corallum and occurred post mortem. There is no indication of a syn vivo coral-barnacle interaction with borings in tissue-covered areas. The authors used micro-CT scans to visualize the 3D morphology of the pits, their orientation, and distribution. Additionally, the 3D morphology of an assemblage of 75 pits was used to carry out ordination and cluster analyses, which showed that previously proposed ichnospecies may be a continuum of morphological variability. In the basis of measurements by the present authors, the studied borings do not fit any known ichnotaxa. The absence of bourrelets excludes the possibility that the borings studied belong to the ichnogenus Rogerella Saint-Seine, 1951. Hence, the results seem to contradict a synonymization that was proposed by Bromley and D’Alessandro (1987) and subsequent authors and leave room for further research and discussion on this topic. Although the inferred boring organism is a filter feeder and, thus, depends on currents, the authors did not find a preferential orientation of the borings. The samples considered here are the best-preserved Devonian barnacle borings to date.

Geologia w Wielkopolsce : od przeszłości po współczesność

Berkowski Błażej, Fedorowski Jerzy, Skoczylas Janusz

Przegląd Geologiczny

2020

Vol. 68, Nr 8

620--627

The full-time studies in geology started in Poznaň in 1919, i.e.when the Piast University (Wszechnica Piastowska) were established, soon after renamed to the Poznań University. Three institutes, namely Geology, Mineralogy and Palaeontology, were created. Scientists employed in those institutes produced nearly 8% of all papers in geology, published in Poland before the Second World War. Already in the academic year 1945/1946, a very small teaching team, lead by Professor K. Smulikowski, re-established the full-time studies in geology at the Poznań University, active until 1952. Only 18 students were able to receive their MSc degrees during that time. From 1952 to 1988, the full-time studies in geology were suspended. The small Chair of Geology offered courses in geology for biology and geography students first, and exclusively for geography afterwards. However, the scientific personnel of the Chair was very active in scientific investigations and publishing. Eight persons, five of them from the outside, received their PhD degrees in geology and palaeontology from the Chair. The intensive effort, started in 1987, resulted in the re-establishment of the full-time studies in Geology at Adam Mickiewicz University in the academic year 1988/1989. Following that important event and thanks to the full-time employment of several outstanding professors in geology, mineralogy, hydrogeology and palaeontology, the Chair of Geology was elevated in November 1990 to the level of the Institute of Geology. In 1992, the Institute of Geology received its permanent seat occupied to date. In 1994, the first geology students were graduated. From that time and until 2019, we graduated 378 BSc, 1017 MSc, 72 PhD and 23 DSc (habilitation), and 11 scientists received the scientific title of full professor.