Diana Nyad wasn’t about to be thwarted again by box jellyfish on her record-breaking swim from Cuba to Key West, FL. She wore a special mask and slathered her body in protective anti-jellyfish cream to protect her from stings as she swam 110.4 miles over about 53 hours. We decided to use this as a chance to learn more about jellies, and we found so much great information we put together a quiz.
1. Box jellyfish are a sophisticated species of jellyfish with a particularly potent sting that can cause paralysis or death. What is another name they are known by?
- A) Ocean spikes
- B) Sea lightning
- C) Sea wasps
- D) Electric jellies
2. What do you call a group of jellyfish?
- A) A bloom or a swarm
- B) A school or a pod
- C) A herd or a gaggle
- D) A field or a medusa
3. How do jellyfish breathe?
- A) Through their tentacles.
- B) Through a small opening at the top of the domed area of their outermost layer (epidermis).
- C) Oxygen dissolved in seawater diffuses directly through their thin skin.
- D) Oxygen enters through their digestive cavity.
4. True or False? Jellyfish live only in salt water.
5. University of Hawaii researcher Angel Yanagihara developed the anti-jellyfish cream containing zinc glucoconate used by Nyad. What prompted Yanagihara to research jellyfish venom?
- A) She saw Nyad on TV and wanted to help her realize her dream.
- B) Sunscreen manufacturers asked her to develop anti-jellyfish cream so they could sell it.
- C) When her research on snake venom led her to Hawaii, she became curious about jellyfish.
- D) She suffered a painful attack by jellyfish while swimming in Hawaii and decided to do something about it.
6. True or false? Some jellyfish are thought to be immortal – they never die.
7. Why are jellyfish populations increasing off the coast of Antarctica, Alaska, Spain and Western Africa?
- A) Humans are establishing jellyfish “farms” to meet demands for edible jellies.
- B) Tourism (lots of people in the water) in nearby areas is driving the jellies to quieter waters.
- C) Overfishing and pollution are creating jellyfish-friendly habitats in those regions.
- D) Changing weather patterns are also changing ocean currents that are moving the jellies to those areas.
8. What is the most common predator of jellyfish?
- A) Whales
- B) Sea turtles
- C) Swordfish
- D) Other jellies
9. True or false? If a jellyfish stings you, urinating on the sting takes away the pain.
10. What jellyfish feature led to a Nobel Prize?
- A) Box Jellyfish Venom.
- B) Green Fluorescent Protein.
- C) Mesoglea Mucosa.
- D) Nematocyst Electricity.
Match the fact in the first list to the corresponding number in the second list (special thank to the National Science Foundation for this great data):
- A) The number of minutes it takes a serious box jelly sting to kill someone.
- B) The number of eggs that may be released daily by a single jellyfish
- C) The number of feet in length of the tentacles of a Lion’s Mane jellyfish.
- D) The number of people stung by jellies every year in the Chesapeake Bay.
- E) The number of people in the Philippines killed every year by Box Jelly stings.
- F) The number of Dead Zones in world oceans – areas too polluted to harbor any significant marine life except jellies.
- G) The number of refrigerator-sized jellies that float in the Sea of Japan during jellyfish blooms.
- H) The number of years it took for invasive, fast-reproducing comb jellies to completely dominate the Black Sea
- a) 8
- b) 400
- c) 45,000
- d) 20-40
- e) 500,000
- f) 3
- g) 100
- h) 500 million
1. C. Sea wasps. Unlike many other jellyfish, box jellyfish have eyes (4 of them, one on each “side”) and other visual detectors call ocelli that can detect light. These, along with a very simple brain, allow box jellies to actually hunt their prey rather than float randomly into their food source. Depending on the specific subspecies, the box jellyfish sting can cause discomfort that is short term and mild, long and painful, or fatal. For Nyad, the box jelly stings on her previous swims were painful and paralyzing enough to force her to cut short her long term swim.
Most jellyfish have three layers: the outer layer (epidermis), the middle layer (mesoglea) that is its trademark thick, elastic, jelly-like substance; and the inner layer (gastrodermis). They have a simple nervous system (nerve net) that can smell, detect light, and respond to other stimuli.
2. A. Bloom or a swarm.
3. C. The oxygen in seawater diffused directly through the skin. Jellies are very simple creatures – they don’t have lungs, hearts or brains, but they do have a have a lone digestive cavity that serves as both stomach and intestine, with a single opening for food and excrement travel through.
4. False. Called Craspedacusta sowerbii, freshwater jellies have been spotted in North and South America, including almost every state in the U.S. Alabama, New Hampshire, and Missouri have online resources that can help you spot them locally.
5. D. After her painful run-in with box jellies, Yanagihara wanted answers. She explains, “The fiery pain and days-long agony got my full attention. As a biochemist, I was completely intrigued, but as a sting victim, it was personal. I needed to know more.” Often personal experience leads to valuable research!
6. True. At least one species of jellyfish, Turritopsis dohrnii, is currently being studied because it appears to have the ability to reverse the aging process and regenerate itself indefinitely. At any point in its life, it can turn itself back into a polyp, the earliest stage of jellyfish life. This ability to throw itself into reverse led scientists to nickname it the “Benjamin Button” jellyfish. Scientists have also explained it as being akin to a butterfly that, rather than dying, turns itself back into a caterpillar.
7. C. Fish eat jellies, and fewer fish means more jellies in the water, so overfishing is a serious problem. Also, fewer fish means that there is less competition for their primary source of nourishment, zooplankton, so jellies reproduce faster with the increased availability of food. Also, jellies are not picky eaters and so thrive in waters where pollution has killed off other sea life.
8. D. Other jellies are most likely to eat their fellow jellyfish, but all of the others on the list eat them as well (and sharks eat them, too). Seabirds sometimes ingest jellies when they are attached to crustaceans floating near the surface of the water.
9. False. Although urine for jellyfish stings is a popular folk remedy, it may actually make things worse, as does rinsing in fresh water. Jellyfish tentacles have millions of stinging cells in them called nematocysts that pierce the skin and inject venom when the tentacles touch you. Some experts say a good way to deactivate the nematocysts is remove any tentacles from your skin (don’t use your bare hands), and treat the wound with something acidic, like vinegar. After that, scrape off any remaining jellyfish matter with something flat and dull, like a credit card.
10. In 2008, Shimomura, Chalfie and Tsien won the Nobel Prize in Chemistry for their work with GFP, a fluorescent tag first extracted from jellyfish that allows scientists to “light up” the tissue that expresses a certain gene.
Matching facts and numbers
- A) The number of minutes it takes a serious box jelly sting to kill someone: (f) it can take as little as 3 minutes for a box jellyfish sting to be fatal
- B) The number of eggs that me be released daily by a single jellyfish: (c) 45,000 eggs
- C) The number of feet in length of the tentacles of a Lion’s Mane jellyfish: (g) tentacles that are 100 feet long
- D) The number of people stung by jellies every year in the Chesapeake Bay: (e) 500,000 people
- E) The number of people in the Philippines killed every year by box jelly stings: (d) 20-40 people killed
- F) The number of Dead Zones in world oceans – areas too polluted to harbor any life except jellies: (b)400 Dead Zones
- G) The number of refrigerator-sized jellies that float in the Sea of Japan during jellyfish blooms: (h) 500 million jellies during the bloom
- H) The number of years it took for invasive, fast-reproducing comb jellies to completely dominate the Black Sea: (a) 8 years for the jellies to overwhelm that body of water