![]() Over the last two decades, molecular, biochemical and isotopic tools have improved our understanding of the feeding habits of various soil organisms, yet this knowledge is still to be synthesised into a common functional framework. Simultaneous assessment of the functional roles of multiple taxa is possible using food-web reconstructions, but our knowledge of the feeding habits of many taxa is insufficient and often based on limited evidence. Soil ecologists often operate with functional groups to infer the effects of individual taxa on ecosystem functions and services. Soil organisms drive major ecosystem functions by mineralising carbon and releasing nutrients during decomposition processes, which supports plant growth, aboveground biodiversity and, ultimately, human nutrition. This distinction between anecic Lumbricus and Aporrectodea earthworms is expected to have different consequences for soil trophic network and soil functioning such as carbon and nutrient cyclings, water regulation and soil structure maintenance. Consequently, LAS seem to benefit from easily assimilated substrates, grow faster and reach maturity in a shorter time span than AAS species. This suggests that AAS burrow into the soil to search for soil organic matter incorporated in the soil whereas the LAS essentially focus on burying the surface litter into their burrow. Furthermore, the AAS have a denser and more complex burrow network than LAS. In contrast, Aporrectodea anecic species (here after "AAS") consume mainly aged plant-derived materials already incorporated into the soil and only a small proportion of surface-available plant-derived materials. In this review we highlight that within anecic earthworms, Lumbricus anecic species (here after "LAS") mainly consume fresh plant-derived materials on the soil surface modifying the quantity and spatial organisation of said materials. However, since these ecological categories were first defined, many studies on the ecological traits of widespread anecic species: Lumbricus centralis (Bouché, 1972), Lumbricus terrestris (Linnaeus, 1758), Aporrectodea longa longa (Ude, 1885) and Aporrectodea giardi (Ribaucourt, 1901) have revealed two distinct feeding behaviours, as well as differences in their growth rates and burrowing behaviour. The recognition of pre- and post-depositional trace fossil suites ensures ichnological and ethological fidelity of faunal data on plant–animal interactions.Įarthworm species in temperate climates have usually been classified into three main ecological categories according to their morpho-anatomical, physiological and ecological traits: epigeic, endogeic and anecic. Less common post-depositional trace fossil assemblages of depauperate diversity indicate that stressed habitats prevailed at the depositional sites and a limited time window for preservation of plant–animal interactions. Low diversity and persistent rarity of post-depositional traces (4%) as compared to more common pre-depositional traces (7%) in the sample population are noted. Accordingly, five taphonomic pathways are proposed based on varied combinations of pre- and post-depositional traces, emplaced on leaf fossils. Preserved traces in the leaf fossils depict arrays of pre- and post-depositional events (viz., biotic interactions on green foliage, leaf detachment from the trees, post-mortem transport and burial) along taphonomic pathways. Both feeding (herbivory/detritivory) and locomotary animal traces are interpreted in the host media. Animal traces that extend beyond the margins of the leaf compressions or are emplaced on the leaf impressions are evidently post-depositional, preserved ex situ. The leaf fossils indicate both above-ground (pre-depositional) and on-ground (post-depositional) animal activities. Plant–animal interactions investigated largely in Glossopteris leaf fossils (1214 specimens) from the lower Permian strata of peninsular India reveal evidence of taphonomic modifications of the ichnofabric. ![]()
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