Dickinsonia is one of those pesky Ediacaran mysteries which persistently defies classification. Think of an animal group and someone has suggested that Dickinsonia belongs to it. Think of a group outside of Animalia and there’s a decent chance that Dickinsonia has been placed there too. In more recent years, there has been a tendency to see it as a potential placozoan – the simplest of animals – often in a very cautious manner, or at least that it is at the same grade of complexity (for an example of the case for a placozoan affinity, see here, for insight into just how difficult it has been to classify Dickinsonia, see here). A recent study into the development of Dickinsonia claims to provide strong evidence that it is indeed an animal, though without assigning it to any particular group. It effectively states that Dickinsonia is an animal, so let’s put aside the claims that it is not and focus on where it fits on the animal evolutionary tree. See for yourself, here.
This gained a lot of press coverage back in September, though one, in particular, stood out to me. The Week decided to go with the brilliant headline “550-million-year-old thingamajig determined to actually be an animal”. I honestly can’t express how much I love that Dickinsonia has been labelled a “thingamajig” as it is perfect. Dickinsonia is head-scratchingly confusing, it is rightly considered to be a Rorschach Test for palaeontologists, it is, quite simply, a baffling thingamajig. It’s just a shame that the term has no taxonomic value.