Temat: ammonoidea - Katalog OPAC zbiorów

Skocz do pozycji: 1.

Tytuł:: The origin of ammonoid locomotion
Autorzy:: Klug, C
Korn, D.
Powiązania:: https://bibliotekanauki.pl/articles/21156.pdf
Data publikacji:: 2004
Wydawca:: Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:: phylogenesis
Bactritida
ontogenesis
Ammonoidea
conch
coiling
Devonian
paleontology
locomotion
ammonoid
Opis:: Evolution of the coiled ammonoid conch from the uncoiled bactritid conch was probably coupled with changes in manoeuvrability and swimming velocity. The gradual transformation of uncoiled to coiled ammonoid conchs has essential functional consequences. The radical change in conch geometry during phylogeny but also in ontogeny of early ammonoids implies a shift of the aperture from an original roughly downward, via a downward oblique and an upward oblique to an upward orientation, presuming a neutrally buoyant condition of the ammonoid animal. Similar trends were reconstructed for the three main ammonoid lineages in the Middle Devonian, the agoniatitid, the anarcestid, and the tornoceratid lineages. This allowed an increase in manoeuvrability and in the maximum horizontal swimming speed.
Źródło:: Acta Palaeontologica Polonica; 2004, 49, 2
0567-7920
Pojawia się w:: Acta Palaeontologica Polonica
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 2.

Tytuł:: Devonian pearls and ammonoid-endoparasite co-evolution
Autorzy:: De Baets, K.
Klug, C.
Korn, D.
Powiązania:: https://bibliotekanauki.pl/articles/23478.pdf
Data publikacji:: 2011
Wydawca:: Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:: Algeria
Ammonoidea
Devonian
Germany
Morocco
Trematoda
paleontology
parasite
pearl
evolution
terminology
distribution
ammonoid
endoparasite
Opis:: Raised shell projections on the inner shell walls that form pits on the internal moulds of Devonian ammonoids have been known for several decades. New specimens from Morocco reveal novel details of these structures; most, if not all, of which consist of a capsule of ammonoid shell that covers tiny tubes attached to the outer (= lateral or ventral) shell wall from the inside. In accordance with comparable Recent occurrences of similar structures in molluscs, we use the term “pearls” for these structures and the pits they form on the internal moulds. The nature of these encapsulated tubes is described and discussed. Because of the presence of these tubes inside the pearls, pearl arrangement, and their similarity to Recent mollusc occurrences, the tubes are interpreted as traces of parasitoses. The pearls and pits were grouped into five types based on differences in morphology, size, and arrangement. Then, having used these traits to perform a simple cladistic analysis, the resulting cladogram was compared to the phylogeny of ammonoids. Based on this comparison, it appears likely that the parasites underwent a co−evolution with the ammonoids, which lasted 10 to 15 Ma. Patterns of evolutionary events include co−speciation, “drowning on arrival” (end of parasite lineage near base of a new host clade), and “missing the boat” (parasite lineage does not adapt to a new host clade, thus not evolving a new parasite clade). Because of the lack of fossilised soft tissue, only speculations can be made about the systematic affiliation of the parasites, their life−cycle, infection strategy, and ecological framework. Some co−occurring bivalves also have pits reminiscent to structures caused by trematodes in Recent forms. Based on the available information, the tubes are interpreted as artefacts of trematode infestations, which, if correct, would extend the fossil record of parasitic trematodes into the Early Devonian.
Źródło:: Acta Palaeontologica Polonica; 2011, 56, 1
0567-7920
Pojawia się w:: Acta Palaeontologica Polonica
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 3.

Tytuł:: Sublethal injuries in Early Devonian cephalopod shells from Morocco
Autorzy:: Klug, C.
Powiązania:: https://bibliotekanauki.pl/articles/22322.pdf
Data publikacji:: 2007
Wydawca:: Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:: Ammonoidea
Bactritoidea
Devonian
Early Devonian
Gnathostomata
Morocco
cephalopod
paleontology
shell
predation
life mode
ectocochleate cephalopod
Opis:: Internal moulds of the relatively small− to moderate−size shells of Early Devonian ectocochleate cephalopods (typically <150 mm diameter) occasionally display traces of repaired shell damage. Presumably, these animals with their highly specialized buoyancy device, the phragmocone, lived in the water column. It is uncertain as to how the shells of these animals were damaged; one likely cause would be predatory attacks but the identity of the perpetrator remains uncertain. So far, no remains of arthropods capable of breaking or cutting shells have been found in the fossiliferous outcrops of this age in the Anti−Atlas (Morocco). The only macrovertebrate remains of this age are of acanthodian and placoderm fish which probably lived a more or less benthonic life style. Additionally, a fish attack on these cephalopods would probably have destroyed most of the thin−shelled conch and killed the animal. Most of the repaired shell breaks are triangular in shape which is characteristic for cephalopod bite marks. Additionally, the paired arrangement of the fractures in over 70 bactritoids supports the hypothesis that it was a cephalopod attacking another cephalopod. It cannot be excluded with certainty that occasional vertebrate attacks left traces on their shells. Fossil evidence indicates that the development of tightly coiled conchs was a rapid evolutionary event in the Ammonoidea in the Early Devonian; however, the evolution of coiling is probably not directly related to predation pressures because the ratio of injured to healthy specimens is roughly the same in Zlíchovian bactritoids with orthoconic and ammonoids with coiled shells.
Źródło:: Acta Palaeontologica Polonica; 2007, 52, 4
0567-7920
Pojawia się w:: Acta Palaeontologica Polonica
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 4.

Tytuł:: Hydrodynamically controlled anagenetic evolution of Famennian goniatites from Poland
Autorzy:: Niechwedowicz, M
Trammer, J.
Powiązania:: https://bibliotekanauki.pl/articles/22390.pdf
Data publikacji:: 2007
Wydawca:: Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:: environment change
Famennian
hydrodynamics
Ammonoidea
Polska
Devonian
evolution
Holy Cross Mountains
Tornoceratidae
paleontology
fossil animal
ammonoid
Opis:: This paper reports on the evolution of ammonoids belonging to the family Tornoceratidae from the Devonian of Janczyce in the Holy Cross Mountains, Poland. Steady and gradual changes in conch morphology of the goniatite lineage Phoenixites frechi–Tornoceras subacutum–T. sublentiforme occurred in concert with water shallowing during the deposition of the Lower Famennian cephalopod limestone. Biometric analysis of ammonoid conch and facies analysis of the cephalopod limestones have been applied to assess the possible relationship between shell geometry and environmental changes. Results show that ratios of whorl width / diameter as well as whorl width / whorl height decreased, while distance from the venter to the greatest whorl width / diameter increased with time, thereby reducing hydrodynamic drag of the shells, probably in response to increasing water turbulence. The interpretation presented here is in agreement with similar cases from the literature. However, this kind of environmentally controlled evolution has hitherto been recognized only in Jurassic and Cretaceous ammonoids. Conch morphology may be considered as an indicator of palaeobathymetry.
Źródło:: Acta Palaeontologica Polonica; 2007, 52, 1
0567-7920
Pojawia się w:: Acta Palaeontologica Polonica
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 5.

Tytuł:: Emergence and collapse of the Frasnian conodont and ammonoid communities in the Holy Cross Mountains, Poland
Autorzy:: Dzik, J
Powiązania:: https://bibliotekanauki.pl/articles/21673.pdf
Data publikacji:: 2002
Wydawca:: Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:: Ammonoidea
paleobiology
Conodonta
Polska
collapse
population variability
conodont
community
Frasnian
change
Devonian
evolution
Holy Cross Mountains
paleontology
ammonoid
Opis:: The dominant factor in faunal succession of conodonts in the Frasnian of Poland is the apparent immigration of species originating allopatrically in other regions. Each immigration event usually changes the population variability of a local species (character displacement). Only a few lineages show their phyletic evolution within the studied area. Attempts to distinguish conodont species on the basis of platform element shape failed in some of the latest Frasnian palmatolepidids. Even at the apparatus−based generic level, certain ramiform elements of the apparatus appear much more diagnostic than the platforms. Correlative value of the late Frasnian palmatolepidids of unknown apparatus structure is thus questionable. The evolution of platform elements in Ancyrodella offers a more solid basis for age determination although their great population variability makes resolution rather low and requires the population approach. The panderodontids Belodella(?) tenuiserrata sp., B. minutidentata sp. nov., B. robustidentata sp. nov., prioniodontid Icriodus kielcensis sp. nov., enigmatic monospecific Playfordiidae fam. nov., prioniodinids Dyminodina planidentata gen. et sp. nov., D. anterodenticulata sp. nov., D. kovalensis sp. nov., Pluckidina kielcensis gen. et sp. nov., P. slupiensis sp. nov., P. robustipegmata sp. nov., and P. lagoviensis sp. nov., derived polygnathid Avignathus bifurcatus sp. nov., probably secondarily simplified polygnathid Nicollidina gen. nov., and palmatolepidids Kielcelepis gen. nov., Lagovilepis gen. nov. and Klapperilepis gen. nov. are proposed.
Źródło:: Acta Palaeontologica Polonica; 2002, 47, 4
0567-7920
Pojawia się w:: Acta Palaeontologica Polonica
Dostawca treści:: Biblioteka Nauki