Deep sea 'mushroom' may be new branch of life

Formaldehyde and alcohol are still the best way to preserve samples for physical examination when no genetic work is expected. It's a trade-off.

If these had been stored in a genetically-safe way (say frozen, or dried), they may not have been noticed at all, as it tends to collapse structure, especially with gelatinous animals.

To nitpick: 'phylogenetics' isn't exclusive to using molecular data; the field of phylogenetics was well established long before the advent of sequencing. In modern usage, the term is nearly always referring to molecular phylogenies, but in this context it's a little confusing.

Also, taxonomy is a distinct discipline from phylogenetics, more devoted to classification and naming. The ultimate goal of taxonomists is to assist in communicating about organisms via well-informed classification schemes. To wit, most naming is focused on morphology (e.g. monocots vs. eudicots), but based on molecular phylogenies (hence eudicots (true dicots) vs. the polyphyletic dicots).

It's not uncommon. It's easier to collect than it is to classify. Eg, here's a news report from 1988 about how "[a] 70-foot dinosaur known as Happy stood prominently on display at the Cleveland Museum of Natural History for nearly 25 years before researchers discovered it was a new species." http://articles.latimes.com/1988-09-25/local/me-3747_1_natur...

It points out that "Museum storerooms have become rich hunting grounds for new species because a lack of money and staff has delayed the identification of bones excavated up to 60 years ago" and that "75% of the museum's collection has not been examined closely."

Nor is it a recent issue. The HMS Challenger expedition of 1872–76, which was the first real oceanographic expedition, took another 19 years to publish everything. (See http://en.wikipedia.org/wiki/Challenger_expedition#Findings_... ).

The Natural History museum in the UK has shelves full of samples dating back >100 years that have never been looked at. Furthermore, even ones that have been studied can be revised in the light of new evidence.

So primarily it's a question of man power and triaging samples. Secondly you need a lot of evidence before declaring a new species and various formal steps should be taken (providing a reference sample etc), so that process in itself can take years+.

You are describing domains, and neither the article nor its title suggested the discovery of a new domain. There's no technical reason I'm aware of for "branch" to be restriced to describing domains of life.

This case appears to demonstrate a new phylum, which is two steps below domain, so it's still significant in terms of classification. The fact that the organisms resemble some others we thought died out long ago is also important for evolutionary biology.

What's fascinating is that finding new animal phyla is apparently something that has happened a few times in the last century, and they aren't able to place this creature into a phyla yet - it's close to a jellyfish and comb jellies, but not close enough to be included in the Cnidaria or Ctenophora phylum.

Wikipedia (bless it's soul) has an update on this - clearly in the kingdom Animalia, http://en.wikipedia.org/wiki/Dendrogramma, they are just trying to figure out which phylum to place it in.

I wondered the same - symmetry seems quite an arbitrary criterion to me, especially because, for example, humans are not really symmetric once you look at the placement of organs. But I could imagine that the mechanism that causes bodies to grow (almost) symmetrically has some deep and unique genetic and biochemical reasons and therefore justifies this classifications.

If archaea are a new branch on the same level as bacteria, why can't new multicellulars be a new branch on the same level as modern multicellular life?

They may be unrelated and different enough - this is one of the ideas about Edicarian fauna.

The statements saying that this may be a sample of Edicarian fauna are pretty speculative. From the original paper:

> We are aware that the similarities to some of the Ediacaran forms may be independent responses to the same environmental necessities, rather than being evidence of homology.

They found similarities between this and some Ediacaran fossils, but that does not mean that they are related. There are other extant animals with similarities to some Ediacaran specimens with no relation between them.

The speculation can be falsified by analyzing this creatures' DNA and find at which point it diverged from other known life. I hope that is possible!

I think you're taking that article somewhat out of context. Saying that this "mushroom" is a new branch on the tree of life has a factual, falsifiable meaning.

There is a real thing that we can't really reconstruct in its entirety: the family tree for all life on Earth. Saying it's a new branch means that it diverged so long ago we can't find anything that looks like a common ancestor.