Fig. 1 Young lion's mane jellyfish. You can see how this might be a problem should a big one kick the bucket near a beach filled with wee ones. Creative Commons jadeilyn

Mayhem. That’s what happened this week when a 40-lb. dead member of the world’s largest species of jelly, Cyanea capillata (literally “blue hairs”, I think), washed up near a New Hampshire beach, and zillions of tiny, nearly invisible fragments of its tentacles fanned out through the water like the evil plan of some very-small-scale Bond villain. 150 people were stung. Five ambulances and a hook and ladder truck showed up. Lifeguards were sent to raid local stores for baking soda and vinegar.

In the understatement of the week, one expert had this to say:

“When you’re talking about thousands of tentacles and little kids splashing about, it’s a recipe for chaos,” Professor Harris said.

Fig. 2 The business end of a jellyfish tentacle. When the little trigger on the upper left is tripped, the operculum (lid) flips back and the nematocyst, or stinger, flips inside out and is propelled by pressure into fish, plankton, stray toddlers, etc.

Scientists said it was no stunner the kids got stung once the jelly entered the bay. Jellyfish tentacles envenomate victims with famous (to biologists) stinging cells called nematocytes that evert a tiny syringe (a nematocyst) when you touch them. They’re like tiny harpoons with hairpin triggers. These cells can remain alive long after the jellyfish does since they rely on seawater, not the rest of the jellyfish, for many of their survival needs.

What really makes the lion’s mane nasty is what you can observe in Fig. 1, over yonder above left: eight clusters of up to 100 gossamer tentacles each. These are young specimens, when they get old and purple, they have enough tentacles to make a New-York ticker tape parade look like a light sprinkle of streamers by comparison. And did I mention the tentacles grow up to 120 feet long? That’s longer than a blue whale.The bell that accompanies 120-foot long tentacles can reach eight feet across. That’s three feet across longer than me. I’m sure the tentacles easily break into tiny, irritatingly noxious and barely visible pieces once the jellyfish bites the big one.

Lion’s mane jellies are found in the cold, northern oceans of the world where it feeds on fish, comb jellies, moon jellies, small crustaceans, and plankton. It was unusual for this to be so far south, according to experts in the NYT article. It brought to my mind the periodic population explosions of monster Nomura’s jellyfish giving Japanese fisherman no end of aggravation, in one case even capsizing a trawler. Jellyfish, people. Jellyfish.

The Telegraph article I’ve linked to here dryly notes the recent periodic explosion in Nomura’s population may be do to fewer predators like sea turtles and fish in the area. Let’s see . . . perhaps because of overfishing? Indeed, jelly populations have been climbing world-round, causing all sorts of headaches. There’s lots of speculation about why, and Smithsonian Magazine even devoted and entire article to it in their recent 40th anniversary edition, but it probably comes down to two things: We’ve caught and eaten many of the other fish that would normally compete with them for food, and the oceans are getting warmer and more acidic, which bothers many things but apparently not jellies. Don’t forget your Monterey Bay Aquarium (or equivalent for other continents) Seafood Wallet Watch Card or iPhone app next time you’re buying seafood.

Lion’s mane jellyfish are true jellies in the phylum Cnidaria (That’s a silent C — Nigh-DARE-ee-uh), a major group of animals that was probably the second group to split off the main animal line after sponges, the Porifera. You can see the broad outline here in this easy-to-understand tree. Though the jellyfish may indeed be beating out my favorites, the slime molds, with their world-domination plans, I don’t love them less. The true jellies are in one group of Cnidaria called the Scyphozoa, but they have all sorts of weird and wonderful relatives like all corals, sea pens, sea anemones, and box jellies containing some of my favorite beautiful organisms on the planet. When I go to aquariums, phylum Cnidaria is the one that mesmerizes me most often. Rest assured, you’ll hear more about them here.

An 1879 tree by Ernst Haeckel with a bit of a bias. The true tree of life is trunkless -- more of a shrub of life, really. There's a root, but no apex. If forced to choose one, personally, my money's on Theobroma cacao.

Last time I posted a link to a slide show of beautiful jellies. But I don’t want this blog to be only about eye candy. I want to help you learn about new organisms, the often crazy or amazing ways they make their livings, and no less importantly, how they are related and classified.

Because I hope to make this blog accessible to all sorts of readers, from precocious 10-year-olds on up, I’ve struggled with how to help you learn about taxonomy without making you digest the long lists of incomprehensible names found in abundance on most trees. On top of that, I face the problem that classifications are constantly changing.

The Trouble with Trees

Today scientists classify organisms based on how they are related to one another, but unfortunately, it’s often quite confusing to figure out. Sometimes comparing one trait — say, tentacle length — yields  one family tree (often called phylogenetic trees by scientists), and comparing another trait  — say, mean number of biologists devoured attempting to study organism — yields a conflicting one. Which is correct? Which traits should you give more weight when constructing the tree you think most likely? This is the problem that has launched a thousand theses. Scientists argue about the true relationships constantly, and the trees are rearranged with every publication of a systematics journal.

On top of that, once scientists started sequencing the genes of different organisms and making trees by comparing them, traditional taxonomies that had been stable for decades or centuries based on body shape, anatomy, or other observable traits were often upended, leaving things in disarray to this day. And finally, the formal names we give ranks above species like kingdom, phylum, class, order, etc., are largely arbitrary, as is the idea that there are exactly seven ranks. There aren’t. The ranks are meaningless as absolute markers, so teaching these names seems to me both confusing and pointless.

And yet . . .

The Learning Tree

Some major groups have remained supported by scientific consensus, and other new groups are settling down. And there are true evolutionary relationships among organisms, and themes within lineages of common descent, though individual species can differ radically from their close kin. Learning the major groups helps keep the dizzying diversity of Earth organized in our brains. Strange new species will no longer float around like stray mental post-it notes, but have a taxonomic hook to hang on when you can say . . . ah, that new creature is an annelid. I know exactly which other creatures it’s related to.

So I’m going to try to start including links to trees with each post. It’ll be up to you to explore them as your fancy strikes you. One site I will rely on heavily is the Tree of Life Web Project. Although the descriptions there are often written by scientists for scientists and will be nigh incomprehensible to the lay person, anyone can look at the trees and get a sense of who is related to who and how. Plus pretty pictures help with scary names. : ) Another benefit  to studying these trees is seeing how many different organisms are out there that you will never have heard of, and about which so little is known. Virtually every page contains groups that even I — with six years of higher education in biology and a passion for, shall we say, creative life forms — have never heard of.

So here we go: For jellies and friends, which are contained in a group with the formidable name Cnidaria (ni-DAR-ee-a), you can see the TOL trees here and here and a cuter and more digestible, if less rigorous, tree here. Cnidaria was one of the first animal groups surviving today to split from the rest of the animals — and it shows.