Fish & Sea Life Quiz — 7 Free Questions

Question 1

Which fish inflates itself into a rigid, often spiny ball by gulping water when threatened, and carries in its organs a nerve poison many times more toxic than cyanide, so that in Japan it is served as the delicacy fugu only by specially licensed chefs?

Question 2

Which reef crustacean, neither an insect nor a true shrimp, strikes with a spring-loaded club or spear so fast the water behind it briefly boils, cracking snail shells and aquarium glass, and sees with the most complex eyes known, carrying a dozen or more colour channels plus polarised vision?

Question 3

Which grey, beak-nosed dolphin of coasts and harbours worldwide, the species usually seen in aquaria and the star of the television series Flipper, gives each individual a signature whistle that works like a name and can be used to call an absent companion?

Question 4

Which upright little bony fish with a horse-like head and a curling, grasping tail swims poorly, anchoring itself to weed, and is famous because the male, not the female, becomes pregnant, carrying the eggs in a sealed belly pouch and giving birth to tiny young?

Question 5

Which is the largest river dolphin, a pink-tinged animal of the Amazon and Orinoco with a long thin beak and, unusually, unfused neck bones that let it turn its head to hunt among flooded forest trees?

Question 6

Which air-breathing fish of the murky rivers and swamps of northern South America, not actually an eel at all but a kind of knifefish, can discharge a jolt of several hundred volts from stacked columns of modified muscle to stun prey and drive off attackers?

Question 7

Which stocky, short-snouted, aggressive shark can adjust its body chemistry to hold on to enough salt to survive indefinitely in fresh water, and so turns up far up rivers and in lakes, having been recorded in the Mississippi, the Amazon, the Ganges and Lake Nicaragua?

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About Fish & Sea Life

This quiz is about life in the sea: the fish everyone knows and the ones almost nobody does, how a fish is built and how it lives, the sharks and rays, the whales, dolphins and seals, the octopus and its kin, the jellyfish and corals, the drifting plankton that feed the whole ocean, and the fisheries and reefs now under strain. One hundred questions in five packs, each describing a sea creature, a group, an adaptation, a record or a conservation story and asking you to name it from four choices of the same kind, then explaining it. Seabirds belong to the Birds quiz and sea turtles to a later one; this is a knowledge quiz, not a picture quiz.

The first pack is the famous inhabitants: the great white and whale sharks, the blue whale, the orca and the bottlenose dolphin, the giant Pacific octopus and the giant squid, the clownfish and the seahorse, the electric eel, the piranha, the anglerfish and the pufferfish, the manta ray and the moray eel, the living-fossil coelacanth, the Portuguese man o' war, the coral polyp, the sea star and the horseshoe crab.

The second pack is how fish work: the swim bladder, the countercurrent gill, the lateral line, the cartilaginous fish, the shark's electric sense, the jawless lamprey and hagfish, the heavyweight sunfish and the ribbon-like oarfish, schooling and countershading, the salmon and the tuna and the swordfish, the flying fish, the mudskipper and the lungfish, bioluminescence, the hitch-hiking remora and the cleaner wrasse.

The third pack is sharks and rays: the tiger, bull, hammerhead, mako, basking, Greenland, thresher, goblin and cookiecutter sharks, the sawfish, stingray, electric ray, skate and eagle ray, the nurse shark, the wobbegong and the walking epaulette shark, shark finning, dermal denticles and the spiracles.

The fourth pack is marine mammals: the sperm and humpback whales, the narwhal and beluga, baleen, the dugong and manatee and the extinct Steller's sea cow, the walrus, the elephant, leopard and crabeater seals, the sea otter, the vaquita and the baiji and the boto, echolocation, the blowhole, ambergris and krill.

The fifth pack is invertebrates, plankton and the wider ocean: the octopus, cuttlefish and chambered nautilus, the mimic octopus, the colossal squid, the box, immortal and lion's mane jellyfish, coral bleaching and the zooxanthellae, the crown-of-thorns starfish, hydrothermal vents and the giant tube worm, phytoplankton and diatoms, the daily vertical migration, kelp forests, the Grand Banks cod collapse, bycatch and the mantis shrimp.

The wrong answers are always other sea creatures or ocean terms of the same kind. About a quarter of the questions carry a neutral photograph of open water, a kelp stand or a fishing net, chosen because it names no species and so cannot point to any option. Facts have been checked against standard reference works.