An Aquarium Teaches Kids About Domestic Life

And what, I ask you, are we to think of the viviparous fish, those that actually pair off in no uncertain manner and a little later bring forth living young! (You catch the drift?) What of the Guppyi, the Helleri, the Tetras and Danios and other tropicals with which our apartments are full to overflowing? Well, at least they keep our own offspring off the streets; you can hardly pry them away from the tank. They might miss something. I always say a small aquarium containing several of these d...

 Guppies Evolve Their Spots in Experimentation

Guppies are popular freshwater aquarium fish. As with the pheasants we met in Chapter 3, the males are more brightly coloured than the females, and aquarists have bred them to become even brighter. Endler studied wild guppies (Poecilia reticulata) living in mountain streams in Trinidad, Tobago and Venezuela. He noticed that local populations were strikingly different from each other. In some populations the adult males were rainbow-coloured, almost as bright as those bred in aquarium tanks. H...