Some of the more massive limestone beds in the Nama group are chock full of stromatolites, the remnants of sizeable Precambrian algal reefs.

Technically, stromatolites are not true fossils, because the mineralised layers are not directly precipitated by the photosynthetic algal mats whose growth they record. Instead, accumulating sediment particles (in these cases, inorganically precipitated calcium carbonate) bind to, and are cemented together by, mucus produced by the algal colonies, which continuously grow upwards to avoid being smothered and cut off from the sunlight.

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The base of the Cambrian is traditionally thought of as the point at which large, mineralised body fossils first appear in the geological record, giving us a much-improved record of the development of life up to the present day. However, the latest Neoproterozoic was not purely the domain of bacteria and algae – some rather more interesting and enigmatic fossils are patchily preserved. Namibia is a good place to find these Ediacara (sometimes referred to as the ‘Vendian fauna’). I came across a surprising number of them, given that I’ve come up empty in some of the most fossil-rich localities in the British Isles.
The highlight was probably this critter, Pteridinium:

This is not a body fossil – nothing remains of the original animal, just the impression it left on the sediment. The level of detail is surprising given that it is found in relatively coarse-grained sandstone; it is thought that encrusting algal mats helped to stabilise the sediment surface and allowed the mould to survive burial. This ‘death-mask’ preservation is fairly unique to fossils of this age, because it is inhibited by algal grazing and bioturbation, both much more common after the beginning of the Cambrian.

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