In the Freshwater Aquarium

15 Points Per Correct Answer - No time limit  

1. "Shelldwellers"-- the "desktop cichlids"-- are miniature cichlids that defend a small territory based on an empty snail shell in Africa's Lake Nyasa. Lake Victoria. Lake Tanganyika. Lake Malawi.

2. Some fish colors are produced by pigment-bearing cells in the skin. But the interference patterns of light as it's refracted among closely-layered guanine crystals are responsible for fishes' butterfly-wing "structural colors" in shades of blue and green. silver and white. red and gold. olive, cream and brown.

3. The phrase "balanced aquarium" is about a hundred and fifty years old. It refers to the balance of the nitrogen cycle. between carbon dioxide and oxygen production. of fish species in a harmonious community. between carnivores and herbivores.

4. The world's first public aquarium was opened in 1853, situated prominently in Hamburg. Paris. London. New York.

5. The sensitive "feelers" of Pearl Gouramis and Three-Spot or Blue Gouramis, and of Dwarf Gouramis too, are actually highly developed pectoral fins. ventral fins. caudal fins. opercular fins.

6. The Amazon is perhaps the world's oldest continuously-flowing river system, with the largest number of tropical fish species of any single watershed. Its sediment in the Atlantic Ocean is visible from space. Has it ever emptied into the Pacific? Yes No

7. If you maintained a separate "species" aquarium for each and every genuine species of fish scientifically described so far, both in freshwater and in the seas, how many tanks would you need? Just over 12,000. About 26,000 or so. About 7 or 8000. More than 90,000 aquariums.

8. Your plants are overrun with snails! You pick out all the large ones. Which fish will do the best job of finding all the little ones and eating them? Clown Loaches (Botia) Bala Sharks (Balantiocheilus) Common Pleco catfish (Hypostomus) Angelfish (Pterophyllum)

9. The closer you look, the more kinds of tiny worms you see in the aquarium, all less than half an inch long. Some glide along the glass. Others thrash in mid water. Still others work through the gravel. None of them is a parasite. an invertebrate. a nematode. a planarian.

10. Zebra Danios are one of our most familiar fishes. The heart of "Danio country" has been well-explored. But if you were to strike out around the unexplored edges, finding new Danio species, would you dip your net in the little rivers of the island of New Guinea? northern Burma and Thailand? the grasslands of Paraguay and Bolivia? sub-tropical east Africa?