THE eyes of chameleons are no longer unique among vertebrates, say
biologists who have found strikingly similar ocular abilities in a fish.
Chameleons are renowned for their turret-like eyes which can
move independently and judge depth by varying their focus. But Jack Pettigrew of
the University of Queensland in Brisbane and his colleagues have found that
sandlance fish, Limnichthyes fasciatus, can achieve similar feats. The fish are
voracious predators of copepods, and both the lizards and the fish may benefit
from being able to target their prey without revealing their intentions by
moving their heads (Current Biology, vol 9, p 421).
鈥淭he fish darting out from the sand looks just like a chameleon鈥檚 tongue,鈥�
says Pettigrew. 鈥淭hey are extremely fast and never miss under normal
肠颈谤肠耻尘蝉迟补苍肠别蝉.鈥�
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