10 amazing facts about jellyfish

Since the opening of our Jelly Gallery, people have fallen in love with jellyfish -brainless, spineless, soft-bodied, gelatinous, pulsating, free-floating and tentacled animals with a mysterious intrigue. People have “oohed” and “aahed” over their seemingly effortless beauty and grace. Others have had moments of confusion, over the fact that something that is essentially 96% water and incredibly intricate and delicate, can at the same time have the power to bring nuclear power reactors and aircraft carriers to a standstill. It is mind-boggling, yet completely true.

Tickets for the next Jelly Night are on sale - don't miss out on your chance to learn all about these incredible animals when the world's experts visit Cape Town on 5 November 2019.

The rare pink meanie jelly at the Aquarium has recently created quite a stir, but how much do we know about the more common species? Photo courtesy 6000.co.za.

So, if the Jelly Gallery hasn’t convinced you that jellies and their kin are absolutely incredible, perhaps these 10 facts will change your mind:

Did you know?

1. Some box jellies perform a mating dance. Pretty impressive for a “brainless” animal.

These box jellies are mating - the male pulls the female close with his tentacles, ready to pass his sperm package to her. Image courtesy of Alvaro E. Migotto / NOAA.

2. Recent studies have shown that urinating on a jelly sting is actually not the best medicine. Get the sting off, pour vinegar over the affected area, and then submerge the affected area in hot water.

Image courtesy of Thomas Quine [CC BY 2.0]

3. Jellies are widely consumed in the East. We might all have to learn how to prepare these wobbly critters, since scientists are telling us that for every 3.8 million tons of fish in the Benguela Current, there are 12.8 million tons of jellies.

This looks delicious! Shredded radish served with jellyfish. Image courtesy of insatiablemunch [CC BY 2.0]

4. Added to the above fact, jellies make the perfect banting food. They contain very little fat and 0 ... read that again ... zero carbs! Nom!

The nutritional value of some common jelly species (for all you banters out there). Table sourced from Jellyfish as Food by H. Yun-Hwa, F.M. Leong and J. Rudloe.

5. Zooplankton usually comprises of the larvae or egg stages of animals, but in the case of jellies, adults are actually plankton.

6. Rhizostomae jellies, like the blue blubber jelly, do not have tentacles. Instead, they have oral arms. They also have hundreds of mouths down each of these arms. Yes, hundreds…

Image courtesy of stezz [CC BY-NC-ND 2.0].

7. Jelly polyps change into “scars” when under stress. They can stay in this state for years and years and years and years... then grow back to make more jellies.

Moon jelly polyps - these little ones look nothing like their adult medusae. Image courtesy of vichigh marine.

The adult moon jelly medusae look nothing like their young polyps. Image courtesy of Alex Vasenin [CC BY-SA 3.0]

8. Q: Name one thing that you and I have in common with jellies.

A: We need our sleep.

Scientists have found that even brainless jellies need some downtime to rest. Just like us, they also struggle to wake up.

9. There is a jelly called the Benjamin Button jelly (Turritopsis dohrnii). It ages in reverse if under stress or in danger.

Although also beautiful, and famed for portraying Benjamin Button, Brad Pitt is unable to reverse the effects of aging and is thus not immortal.

10. There is a startup that is turning jellies into eco-friendly nappies and female sanitary items. If you can’t join them, then beat them and turn them into something very useful.

Abundant, fast-growing and easily accessible - it makes sense to use jellies as a sustainable resource. Image courtesy of Allwidewallpapers.

Most of these facts came up during Jelly Night 2017 with jelly experts Prof Mark Gibbons and Krish Lewis. It was an evening of superb fact sharing and appreciation-building for animals that really defy our traditional definition of the word "animal".