Page 176 - Engineering in Nature

Engineering in Nature

Like many other fish, the splendid-looking beta (or Siamese) fighting fish uses its own
waves to determine its surroundings. When threatened, the male warns its young by
beating its fins to sets up waves.

fish's body in a short time. The lateral lines in the fish's body analyze
these time frames and from these vibrations, the fish is able to estab-
lish an image of its surroundings. The fish can acquire more informa-
tion by swimming faster or creating more vibrations of its own.
The system works so well that the fish can perform very detailed
scanning. For example, the Mexican blind cave fish depends entirely
on its lateral lines. Although it has no eyes, it can perceive objects no
larger than a pinhead in the darkness of the cave it inhabits. 55

In low visibility waters in particular, fish which swim in large
schools in close proximity to one another use their lateral lines in
order to detect rapid maneuvers. 56

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