In a paper published recently in the journal American Naturalist, scientists report finding, in 2012 observations, an example of mimicry in birds so effective it went unnoticed until now.
The chick in question is the cinereous mourner (Laniocera hypopyrra). The young ones have to wait three weeks as nestlings before they develop enough to take flight, and their nests on the ground leave the chicks especially vulnerable to predation.
With those odds stacked against it, the bird has taken to apparent mimicry, according to the researchers. In short, it looks and acts like either of two toxic caterpillars -- Podalia or Megalopyge. (See video below to be amazed that the creature isn't actually a caterpillar but a baby bird.)
The chick's down comes in a bright orange hue flecked with black spots, and the team found that after six days the hatchlings even started moving their heads from side to side slowly when disturbed, in a deft impersonation of a caterpillar's movement. It even knows to keeps its more birdly parts tucked to its underside while it's alone and waiting for its next feeding.
The scientists, led by biologist Gustavo Londoño, of the University of California, argue that the bird's slow growth phase of three weeks, coupled with a high incidence of nest predation, were the catalysts for evolving anti-predation tactics such as the mimicry L. hypopyrra employs.
From Discovery News
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