Phosphatic bromalites and microfossils from the Furongian (Cambrian) of northern Poland (Baltica) and palaeobiological implications
(2023) In Palaeogeography, Palaeoclimatology, Palaeoecology 610.- Abstract
The Furongian Słowińska Formation in Poland yielded minute three-dimensionally preserved, phosphatic fossils. Based on shape and structure, two distinct types are identified. The first type comprises sinuously folded, coiled, or spiral string-shaped specimens, interpreted as faecal material, coprolites. The specimens measure between less than one and two mm, the strings being long and against their subcircular to circular cross-section (60–150 μm). Many strings are folded in few to more than 30 regular loops, in this exceptional complexity unknown from any comparable fossil or extant faeces. Fully stretched, such strings may have an estimated length of more than three cm, suggesting continuous production of such faeces and resistance... (More)
The Furongian Słowińska Formation in Poland yielded minute three-dimensionally preserved, phosphatic fossils. Based on shape and structure, two distinct types are identified. The first type comprises sinuously folded, coiled, or spiral string-shaped specimens, interpreted as faecal material, coprolites. The specimens measure between less than one and two mm, the strings being long and against their subcircular to circular cross-section (60–150 μm). Many strings are folded in few to more than 30 regular loops, in this exceptional complexity unknown from any comparable fossil or extant faeces. Fully stretched, such strings may have an estimated length of more than three cm, suggesting continuous production of such faeces and resistance very a longer period after defecation until fossilization. Modelling similar strings indicates that the loops were produced by sidewards swinging of the body end of the producer during forward move. EDS analysis of the strings revealed low silica content, but high amounts of phosphate pointing to a organic-rich muddy bottom, which the producers swallowed and eventually became phosphatized as faeces. The producers of this faeces might have been few millimeter long and benthic, not infaunal worms, yet, none of the putative coprolites can be unquestionably ascribed to a particular animal group. The second type of fossils comprises between 100 and 220 μm long ellipsoidal to spherical forms with a smooth but wrinkled surface. They are interpreted as collapsed and deformed eggs or embryos lacking the egg shell, rather than coprolites made of digested and squeezed remains of possibly phosphatocopid crustaceans, the most abundant component of the Polish and Baltoscandian Orsten-type fossil assemblages. The spheres also have a smooth surface, which in all cases is partly broken off, uncovering an internal mass. This ranges from a small hump of possibly embryonic material in a large void, to a completely round body possibly presenting a late shield-bearing embryo filling the entire space underneath the egg shell. We interpret this second type of fossils as the first evidence of eggs in Orsten-type preservation, most likely belonging to phosphatocopid crustaceans.
(Less)
- author
- Olempska, Ewa ; Błażejowski, Błażej ; Waloszek, Dieter LU and Maas, Andreas
- organization
- publishing date
- 2023-01-15
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- Coprolites, Eggs, Furongian, Late Cambrian, Northern Poland, Palaeobiology, Phosphatocopid Crustacea
- in
- Palaeogeography, Palaeoclimatology, Palaeoecology
- volume
- 610
- article number
- 111350
- publisher
- Elsevier
- external identifiers
-
- scopus:85143856378
- ISSN
- 0031-0182
- DOI
- 10.1016/j.palaeo.2022.111350
- language
- English
- LU publication?
- yes
- additional info
- Funding Information: E. O. thanks Hubert Szaniawski (Institute of Paleobiology Polish Academy of Sciences) for placing the specimens from borehole Hel IG1 at her disposal. Collection of the material from Hel IG1 borehole was financed by grant nr. 2016/21/B/ST10/02334 to Hubert Szaniawski. We warmly acknowledge the help of Mats E. Eriksson from the Department of Geology University of Lund, Sweden for his corrections and suggestions during preparation the first draft of the manuscript. Comments and criticism supplied by the editor and anonymous reviewers greatly improved the quality and content of this manuscript. Per Ahlberg, Department of Geology University of Lund, Sweden, kindly checked geological terminology and John Peel, University of Uppsala, Sweden, is thanked for his help with the language. Thanks also to Piotr Bajdek (Independent researcher) for many helpful suggestions during the early phase of this investigation. Lastly, we are grateful to Paweł Bącal and Cyprian Kulicki (both from the Institute of Paleobiology, PAS) for valuable suggestions related to SEM-EDS analyses. Publisher Copyright: © 2022
- id
- 4de1cc99-7b6a-4e0e-b8fd-59175952e49a
- date added to LUP
- 2024-01-12 10:01:02
- date last changed
- 2024-02-11 08:46:05
@article{4de1cc99-7b6a-4e0e-b8fd-59175952e49a,
abstract = {{<p>The Furongian Słowińska Formation in Poland yielded minute three-dimensionally preserved, phosphatic fossils. Based on shape and structure, two distinct types are identified. The first type comprises sinuously folded, coiled, or spiral string-shaped specimens, interpreted as faecal material, coprolites. The specimens measure between less than one and two mm, the strings being long and against their subcircular to circular cross-section (60–150 μm). Many strings are folded in few to more than 30 regular loops, in this exceptional complexity unknown from any comparable fossil or extant faeces. Fully stretched, such strings may have an estimated length of more than three cm, suggesting continuous production of such faeces and resistance very a longer period after defecation until fossilization. Modelling similar strings indicates that the loops were produced by sidewards swinging of the body end of the producer during forward move. EDS analysis of the strings revealed low silica content, but high amounts of phosphate pointing to a organic-rich muddy bottom, which the producers swallowed and eventually became phosphatized as faeces. The producers of this faeces might have been few millimeter long and benthic, not infaunal worms, yet, none of the putative coprolites can be unquestionably ascribed to a particular animal group. The second type of fossils comprises between 100 and 220 μm long ellipsoidal to spherical forms with a smooth but wrinkled surface. They are interpreted as collapsed and deformed eggs or embryos lacking the egg shell, rather than coprolites made of digested and squeezed remains of possibly phosphatocopid crustaceans, the most abundant component of the Polish and Baltoscandian Orsten-type fossil assemblages. The spheres also have a smooth surface, which in all cases is partly broken off, uncovering an internal mass. This ranges from a small hump of possibly embryonic material in a large void, to a completely round body possibly presenting a late shield-bearing embryo filling the entire space underneath the egg shell. We interpret this second type of fossils as the first evidence of eggs in Orsten-type preservation, most likely belonging to phosphatocopid crustaceans.</p>}},
author = {{Olempska, Ewa and Błażejowski, Błażej and Waloszek, Dieter and Maas, Andreas}},
issn = {{0031-0182}},
keywords = {{Coprolites; Eggs; Furongian; Late Cambrian; Northern Poland; Palaeobiology; Phosphatocopid Crustacea}},
language = {{eng}},
month = {{01}},
publisher = {{Elsevier}},
series = {{Palaeogeography, Palaeoclimatology, Palaeoecology}},
title = {{Phosphatic bromalites and microfossils from the Furongian (Cambrian) of northern Poland (Baltica) and palaeobiological implications}},
url = {{http://dx.doi.org/10.1016/j.palaeo.2022.111350}},
doi = {{10.1016/j.palaeo.2022.111350}},
volume = {{610}},
year = {{2023}},
}