![]() This time is referred to as the Vendian Period (650 to 544 million years ago), and is characterised by the appearance of soft-bodied animal fossils. Multicellular protists appeared in the fossil record more than 600 million years ago near the very end of the precambrian. Animals in numerous phyla appear at (or in many cases before) the beginning of the Cambrian Period. All known Vendian animal fossils had soft body parts- no shells or hard (and hence preservable as fossils) parts. ![]() Multicellular animal fossils and burrows (presumably made by multicellular animals) first appear nearly 700 million years ago, during the late precambrian time (the part of the Proterozoic era termed the Vendian). Cells in primitive animals (sponges in particular) shows similarities to collared choanoflagellates, as well as pseudopod- producing amoeboid cells. ![]() Animals probably evolved from marine protists, although no group of protists has been identified from an at-best sketchy fossil record for early animals. ![]()
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