Fish Facts

With almost 27,000 living species described, and many more yet to be discovered, Fishes are the most numerous of all Vertebrate (Backboned) animals. There are more fish species than all the other Vertebrates combined.

Fish occupy a huge range of habitats on the planet, from mountain streams, to stagnant swamps, to hot springs, and to the deepest trenches of the sea. A few are even able to live where there the lakes and rivers dry up each year, some by constructing a burrow in which they wait out the dry months, others by burying their eggs in the mud where it stays damp enough to survive even though the parents have long since died.

The life span of fish varies hugely, some live for no more than a few months, others are thought to live well in excess of 100 years.

The smallest fish reaches a maximum size of under 10 millimetres, while the largest can attain over 12 metres.

With this huge number of species, the range of required adaptations that Fishes must possess is enormous. Some fish are long and thin, others almost spherical in shape, still others greatly flattened either from side to side or top to bottom. Some have their fins transformed into suckers, or elongated into long streamers, in others the fins are greatly reduced or even totally absent.

There are fish that lack eyes, living out their whole lives in caves where there is total darkness. Wherever they live, they all need to find food, avoid predators, and find a mate, and even the most bizarre appearing fish has a very good reason for looking the way it does, even if it is not immediately apparent to us.

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