41. However, most trace fossils are rather less conspicuous, such as the trails made by segmented worms or nematodes. 42. These left behind fragmentary skeletal remains like teeth and a few bones, as well as trace fossils like footprints. 43. Trace fossils are best preserved in sandstones; the grain size and depositional facies both contributing to the better preservation.44. The organism was first interpreted as a trace fossil , and has also been considered to represent an agglutinating foraminiferan. 45. The trace fossil assemblages in the formation suggest that it was below the wave base and was reasonably well-oxygenated. 46. Brackish-water trace fossil assemblages occur within these bar deposits and demonstrate periodic incursion of marine waters into the estuaries. 47. We just haven't had the tools necessary to discover the fossil or chemical trace fossil evidence of this life. 48. Accordingly, researchers classify trace fossils into form genera, based on their appearance and on the implied behaviour of their makers. 49. Although these trace fossils are of debatable origin, some of them do resemble the trails made by living gastropods today. 50. Numerous trace fossils of dinosaurs have been found in the area and there is a Museum specialized in paleontology in Enciso.
