Quantitative Classification, Functional Morphology And Behavioural Ecology Of Deep-sea Trace Fossils

As faithful records of deep-sea(below 200 m water depth)authochnous behaviours,deep-sea trace fossils are an important window to glimpse the deep-sea biosphere and its evolution.This dissertation proposes a methodology for the comprehensive study of deep-time behaviours of deep-sea trace fossils by quantitative morphological characterization,theoretical morphological analysis,and behavioural ecological analysis.Through detailed observations of more than 200 graphoglyptid specimens from the Upper Cretaceous to Miocene deep-sea flysch deposits of the Polish Carpathians,as well as graphoglyptid records in the literature(1850~2017,79 ichnospecies from 28 ichnogenera),this dissertation proposes a topological morphological classification scheme that is applicable to a broad category of trace fossils.Graphoglyptids are grouped into three key topological architectures: line-,tree-,and net-forms,and are further attributed to 19 topological prototypes.From a systematic quantitative morphological study of the line-form graphoglyptid Helminthorhaphe from the Upper Cretaceous to Miocene deep-sea flysch deposits(46 specimens),it is proposed that geometric and fractal morphometrics can provide morphological parameters with a behavioural background,which help to delineate the boundaries and connection between different ichnospecies.Based on an artificial intelligence model,the various line-form graphoglyptids represent similar behavioural controls,which are closely associated with the bilateral asymmetry in the movement behaviours and nervous systems of the trace makers.Through a comprehensive biological,behavioural,and ecological comparison with modern deep-sea enteropneusts(10 genera and 14 species from 4 families),it is suggested that Helminthorhaphe from the Late Cretaceous to Miocene may have been produced by their ancient equivalents.From detailed ichnological and sedimentological works(20 sections,~120 km in length)on the Late Devonian to Early Carboniferous deep-sea deposits in the western Junggar,Xinjiang,it is suggested that the deep-sea ichnofauna in the western Junggar reflect a complex interplay between surface climatic and deep-sea systems(the archipelagic ocean context under the monsoon climate).On the basis of a detailed analysis of the paleogeographic background of early Carboniferous deep-sea ichnoassemblages in Europe,North America,and the western Junggar,as well as the macroevolution of common deep-sea ichnogenera,this dissertation is able to recognize distinct groups of deep-sea trace fossils showing high dispersal rates(cosmopolitan trace fossils,Phycosiphon,Nereites)and low dispersal rates(endemic trace fossils,Dictyodora),which may be closely associated with the larval developmental styles of marine benthic invertebrates.Trace fossils,as palaeontological entities with an elegant blend of the body plan,behavioural and neurobiological controls as well as organism–environmental interactions,can provide a multitude of information on deep-time behaviours,ecology,and macroevolution.And as a form of animal intelligence,marine invertebrate trace fossils,especially the deep-sea graphoglyptids with diverse morphological types,may shed light on artificial intelligence,artificial life,and the behavioural evolution of higher animals even mankind.