[Music: 'Rhapsody in Blue', George Gershwin]

Robyn Williams: George Gershwin, whose 'Rhapsody in Blue' you're hearing right now, was Lisa Gershwin's great uncle, and they have much in common. The blue that Lisa rhapsodises about is the open ocean and the creatures that live there. She is also a creative spirit whose new book called Stung!: On the Jellyfish Bloom and the Future of the Ocean is a thrilling read. Now she lives in Hobart and has hot news for us about a creature new to science, and a warning about our exploitation of the seven seas.

First, the new species. What is it?

Lisa-ann Gershwin: Oh, it's a fabulous little creature, I'm really excited about it. It has only just been published. It's from New South Wales, and it's a little blubber about the size of a grape and it's a new species, new genus, new family and new suborder. The last time a new suborder of jellyfish was found was well over 100 years ago, and it's just a fabulous little creature that has been hiding in plain sight masquerading as a baby and nobody noticed.

Robyn Williams: How did you find it?

Lisa-ann Gershwin: A photographer named Denis Riek brought to my attention, sent me some photographs, and said, 'What is this?' And I went, 'Holy cow!' And so he delivered specimens to the Queensland Museum in Brisbane and I went to the Queensland Museum where I am an honorary and I go there a lot to study jellyfish, and he brought the specimens to there, and so next time I was at the Queensland Museum I had a look at them, and oh my God, it was a splendid, splendid little creature. So it's not dangerous, but it's just another little jellyfish like so many that we have all around Australia that are just bobbing about doing jellyfish things.

Robyn Williams: But if it's just another one, how is it so different from all the others?

Lisa-ann Gershwin: Its structural features are absolutely just way out in left field. Without getting into the really boring technical bits of taxonomy, it's just so different. And I'm proud to say we gave it the genus name Bazinga.

Robyn Williams: Why Bazinga? Because that's what you said when you found it?

Lisa-ann Gershwin: Yes, well, absolutely. Bazinga for two reasons. One, because of my favourite show is The Big Bang Theory, I can't help it, there's a confession, I absolutely love Sheldon Cooper, what can I say. So in that context, in The Big Bang Theory 'bazinga' means 'fooled you' or 'ha ha got you', and this splendid little animal has been hiding right in front of us, just right in plain sight. And the other thing is that the seven-stringed harp is also called a Bazinga and it has these radial canals, these veins if you will, and they look like strings of a seven-stringed harp, parallel and evenly spaced, and it just has that sort of look to it. So Bazinga seemed like just the right name for it.

Robyn Williams: It's a lovely name, yes, it's almost as wonderful as the name Gershwin. Now, in front of you you've got some specimens which I normally associate with you from when I first saw you in the far north of Queensland, the Irukandji. Introduce me. What have you got in the jar?

Lisa-ann Gershwin: Okay, so I've got two vials in front of me. One of them is a full grown Carukia barnesi, which we lovingly call the common Irukandji. It's actually not that common, it's rare as hen's teeth, but it's commoner than the other species. So this is the one that is causing a lot of problems for tourism and people. A really interesting little creature, it's about the size and shape of a peanut and it's got four tentacles as fine as cobwebs and about a metre long. And it's invisible in water, it's tiny, and its sting is really mild, you don't know that you've been stung, and then you get very, very, very sick. And some people with Irukandji syndrome die, so it's a very serious thing. But I'm working on a project with CSIRO where my colleagues and I have actually figured out how to predict Irukandjis, how to forecast when and where they are likely to occur. And so we are working on this project, I'm really excited about it.

Robyn Williams: How could you possibly predict them if they are so ephemeral?

Lisa-ann Gershwin: Well, it turns out that they only occur during specific conditions, and so the winds and the currents and all of these things, and so we've been able to develop a model to predict these conditions, and it's pretty exciting.

Robyn Williams: So you could give a warning. Is it that they are floating where people might be and other times they are hidden away somewhere else, or is it that they spring forward?

Lisa-ann Gershwin: We think that they are probably hanging around, hunkered down when it's turbulent and maybe not so clear and it's not very favourable for them, because they are kind of like little orchids, they are very delicate and very particular about the weather that they like. And so it has to be nice and calm and lovely, and then it's a nice beautiful day for a swim, for us and for them unfortunately. But when it's a nice beautiful day for a swim we think that they come up from the bottom and that's when they drift in to the beaches where we encounter them. So it's a matter of forecasting when and where those specific conditions are going to occur.

Robyn Williams: Does that cover the box jellyfish and all Irukandji, the dangerous ones, or just one or two of them?

Lisa-ann Gershwin: This is just to forecast the infestations of Carukia barnesi, or the common Irukandji as we call it. So there are other Irukandji species, 14 currently that we know of. So another one that I've got here with me in a jar, it's about the size of the tip of your thumb, and this one is more dangerous than Carukia barnesi but far more rare, and we think that this one primarily occurs out on the reef and farther south and later in the season. It has a different seasonality, different ecology, different occurrence patterns, and it doesn't swarm in the same way that Carukia barnesi does. So it's probably a little bit trickier to predict, but I suppose that's my next project.

Robyn Williams: Your next project…but, you see, these occur commonly in northern Queensland, as I said, but you are now, I can't help noticing, in Hobart. Does that restrict your work in any way?

Lisa-ann Gershwin: No, not at all. So I'm with CSIRO Marine and Atmospheric Research, and this allows me to tap in to all of these amazing scientists that CSIRO has.

Robyn Williams: Are you restricted in the number of jellyfish you can find in the sea around here?

Lisa-ann Gershwin: Most of the really pesky ones are in temperate waters. So we generally think of pesky jellyfish as the ones that sting, but the really pesky ones are the ones that are damaging our ecosystems. Well, maybe 'damaging' isn't really the right word. We are damaging our ecosystems. Jellyfish are simply responding to that and taking advantage of a really great situation. So most of those are actually in the more temperate waters. The stinging ones are up in the tropics. The eco-system problems are temperate for the most part. So being based at CSIRO in Hobart is actually a dream-come-true in so many ways, and of course Tasmania is a beautiful, beautiful place. It's kind of Disneyland for scientists really.

Robyn Williams: Yes, it is. I wonder which animal you might represent in many ways. Your book is quite magnificent, I can see why Chicago said yes without even blinking, and it's got so many stories. All I can say to listeners is if you're interested in this general field and life in the ocean, have a read. But you seem quite bleak at the end about our prospects. Why?

Lisa-ann Gershwin: Well, when I first started writing the book and doing the research, I actually thought that it was still salvageable. I thought that we still had time. Because I read these other books about climate change and about overfishing and all of these, and they all say that if we hurry up and do something, we can still salvage it. And so I started out with this idea that we needed to be aware that jellyfish play a role in these ecosystems that we haven't been paying attention to. I guess I came to a realisation that it was a lot worse than I thought it was. We've done a lot more damage in a lot more ways, and I was really quite moved by how comprehensively we have damaged our ecosystems. I was also quite moved by how much we humans refuse to take that on board, and this really frightened me because I realised that the damage is really bad.

Robyn Williams: So bad that Lisa Gershwin has an ending to her book I thought you should hear. It's quite uncompromising. These are some of the final paragraphs of Stung!, read by the author herself:

Lisa-ann Gershwin: When I began writing this book, I had the idea that contributing to public understanding would be kind of groovy. At the time I had a naive gut feeling that all was still salvageable and that by really 'getting it', we would still have time to act. I even thought that we could hand our children a better world, with all the perks we enjoy plus a bit of extra wisdom gleaned along the way.

But I think I underestimated how severely we have damaged our oceans and their inhabitants. I now think that we have pushed them too far, past some mysterious tipping point that came and went without fanfare, with no red circle on the calendar and without us knowing the precise moment it all became irreversible. I now sincerely believe that it is only a matter of time before the oceans as we know them and need them to be become very different places indeed. No coral reefs teeming with life. No more mighty whales or wobbling penguins. No lobsters or oysters. Sushi without fish.

In their place, we shall see blue-green algae, emerald green algae, golden algae, flashing blue algae, red tides, brown tides, and jellyfish. Lots of jellyfish. The seas were dying for us to notice their distress, but we collectively chose to overlook the red flags. Of course, we didn't need to listen, we know better: we are Homo sapiens…the wise man.

Throughout the history of life on Earth, major macroevolutionary events, such as mass extinctions and periods of intense evolutionary diversification, have been linked to global-scale changes in environmental conditions. Even relatively small changes in climate have driven major ecosystem change through sea-level fluctuations leading to the opening of straits or the emergence of isthmuses. Today's overfishing, pollution, and greenhouse gas emissions are comparable to the intense global warming, acidification, hypoxia, and mass extinctions through history…all at once.

It is unlikely that all life in the oceans will disappear, or that photosynthesis will simply cease; it is, however, likely that our marine ecosystems will undergo radical simplification. This is already occurring in many locations around the world. Diatoms are being out-competed by flagellates. Large copepods are being replaced by small copepods. Fish-dominated systems are flipping to jellyfish-dominated systems. High-energy food chains are being replaced by low-energy food chains. Jeremy Jackson explains it best.

By fishing down our food webs and initiating trophic cascades, we are removing the large predators—the things with teeth. Ocean acidification is dissolving the hard parts of corals, molluscs, echinoderms, and crustaceans, sparing only the soft squishy species. And hypoxia is killing off even the species we can't bring ourselves to care about.

Jackson has been quoted a lot lately in the popular press for his view that we are creating a 'rise of slime'. And he appears to be right. For a glimpse of what our oceans may look like in the future—and maybe not all that far, in my lifetime and yours—jellyfish evolved in a world devoid of predators, and their only competitors were each other. Long before plants and animals became abundant, the seas were anoxic or hypoxic. About 2 billion years of low oxygen—only 10% of today's levels—oxygen shot up around 750–800 million years ago. The oldest unambiguous jellyfish fossils are from the Ediacaran period about 565 million years ago.

The Ediacaran ocean had small phytoplankton, such as cyanobacteria and flagellates, whereas diatoms didn't evolve for another 400 million years. Big predators, such as fish and whales, didn't evolve until much later when a higher energy food chain was possible, 300 million years ago for fish and 100 million years ago for whales. Diatoms had become abundant by the time marine mammals evolved, but the Ediacaran ecosystem appears to have been based primarily on jellyfish-type ecology. The climate and the ecosystem were jellyfish heaven, in which they ruled the seas for nearly 100,000,000 years as top predators.

The ancient seas were dominated by flora and fauna similar to those that today's seas appear to be shifting toward. No spectacular coral reefs. No vast filtering mussel beds. No sharks slicing through the water, just jellyfish, lots of jellyfish. It might seem outlandish and farcical to think that jellyfish could rule the seas, but they've done it before, and now we have opened the door for them to do it again. Jellyfish are weeds. They are opportunists, and when they have the opportunity, taking over is probably, to some extent, just what jellyfish do.

If you are waiting for me to offer some great insight, some morsel of wisdom, some words of advice…okay then…

Adapt.

Robyn Williams: Lisa Gershwin reading from her book Stung!, published by the University of Chicago Press.