The trace fossil Rejkovicichnus necrofilus Mikuláš et. al., 1996 (Middle Cambrian, Czech Republic): an early example of “gardening”

The trace fossil Rejkovicichnus necrofilus Mikuláš et al. 1996 is reinterpreted as a record of cultivation of microbes for feeding purposes. The process is reconstructed as follows: the tracemaker made a trench in the substrate, then filled it by large bioclasts from its neighbourhood; the filled trench was left for the cultivation of bacteria; finally, the trace fill was reworked by the tracemaker to feed on its microbial content. The small trilobite Litavkaspis rejkovicensis is suggested as the possible tracemaker, as its complete carapaces are often found in the fill of Rejkovicichnus.