The sea gooseberry is not a fruit. But when I first see one, I don’t know what it is at all. I’m at a birthday party on a beach in the Hebrides and, though it’s overcast and chilly for June, a group of us go for a swim. We’re throwing a beach ball between us and splashing around when Greg shouts jellyfish. He’s been stung. He points at a spot beneath the waves and the group edge around it, curious, but scared to get too close. There’s a compass jellyfish beneath the surface, a large yellowish orb with an amber star pattern bursting from its centre, moving with the current, tentacles streaming. I was stung by one a few summers back. They are not dangerous, and their sting nothing more painful than a nettle, the thin red welt disappearing swiftly. This compass jellyfish has left a long, slender mark on Greg’s arm. The group, after observing the creature for a bit, decide that we’re tired of swimming, and rather cold. We retreat, heading for the windbreakers and camping chairs at the top of the beach.
As we walk out of the surf, Greg tracing his finger over the faint pink line on his forearm with curiosity, someone points out something glinting in the sand. I crouch down to have a look. It’s small as a marble, oval, transparent, and gleams where the light touches it. It’s gelatinous, glassy, like a solid drop of water. Thinking of the creature we all just fled, we wonder if it’s a baby jellyfish. But it doesn’t seem to have tentacles. I’m not keen to touch it, just in case. We glance around and see more of them in the strandline. Tiny, beached, shimmering.
Greg’s brother Adam picks it up. It rolls softly in his palm. Adam always carries a pocket magnifying glass with him, for moments like these I suppose. I think he usually uses it to identify fungus and slime moulds, a hobby Greg and his other brothers are affectionately revolted by. (They were also horrified when he deliberately grew some mushrooms under his staircase.) The group takes turns with the magnifying glass, each of us placing the delicate creature on our palms and peering at it with one eye shut, the other close to the glass. Its symmetrical oval form is ribbed lengthways and, while the grooves are smooth, the top of each ridge has little horizontal indentations all along it, like a beautiful carved glass bead.
As we pass it around the group, I look it up. It’s a sea gooseberry, Pluerobrachia pileus. Though it looks like a jellyfish, and even usually has two long tentacles, it is not a ‘true jellyfish’ but a comb jelly. True jellies are cnidaria, while comb jellies evolved along another line, that of the ctenophora, which are gelatinous sea creatures that look a bit like jellyfish. Comb jellies have little hair-like cilia, which I suppose we could only have seen under a microscope, that they use to pulse through the water, creating a shimmering effect as they waft. These must have seemed like the teeth of a comb to whoever gave them their common appellation. Though they have no bones or hard body parts, fossilised comb jellies have been found dating as far back as the early Cambrian period, over five hundred million years ago. Back then, the only animals on Earth were combs and sponges; scientists are unable to agree which came first. The sponges stayed put and the jellies swam about. Then came other simple fauna, the ancestors of today’s molluscs, jellyfish, corals, worms, and the like. But for millions of years, sea gooseberries and their fellow comb jellies were the only creatures moving through the oceans.
Sea gooseberries use their long ‘fishing tentacles’ to catch plankton. The tentacles, which can be up to fifty centimetres, twenty times the length of their body, can be completely retracted. I wonder if the one we’re examining contains its tentacles within, invisible even when magnified, or if it has somehow lost them at sea. Though the name sea gooseberry suggests a small fruit, it is actually a tiny predator, hunting even tinier prey. That is why they are here, washed up along the British coast, following the summer abundance of plankton that blooms beneath the sun. Sea gooseberries create their own light too, at night. They are phosphorescent. No one knows why. If we stay on the beach long enough, we might see them lighting up the sea in constellations beneath the surface. But there’s cake to eat, and someone has taken out a guitar. The conversation moves on, people take turns changing out of their swimming costumes in the beach hut and settling into camping chairs to sing and drink wine. Greg’s arm feels better already, the welt from the compass jellyfish sting now almost invisible. I wonder what happened to the sea gooseberry. Perhaps someone dropped it on the sand and the rising tide has taken it. Sea Gooseberries are almost entirely made of water, so if it’s dead, it’ll dissolve back into the waves.
It seems extraordinary that something so small and vulnerable could have survived for millennia, through five mass extinction events, unscathed. Unlike most sealife, jellyfish and comb jellies are thriving in warming waters, their numbers increasing in huge blooms with ocean acidification. Scientists say they could be some of the few animals to benefit from climate change. It’s a strange comfort to think that, unlike so many species devastated by the current human-caused sixth mass extinction, sea gooseberries will probably still be here in a few million years’ time. They may well outlast us humans. Imagine; the oceans of the future glimmering with exquisite, luminous sea gooseberries.
Saskia McCracken
Saskia McCracken is completing her nature writing debut, Awful Creatures: Encounters with Britain’s Unlovable Animals. Her poetry and short fiction publications include Imperative Utopia (-algia press), Cyanotypes (Dancing Girl Press), Common Name (Osmosis Press), and Zero Hours (Broken Sleep Books). She was shortlisted for the Future Places Environmental Essay Prize.