This bird lays fake eggs to kill rivals

Turns out, some cuckoos are more cunning than you'd think, using dummy eggs to get the job done

By Smartasaurus· 1 min read Wild

Think about a bird that doesn't just steal a nest... it…

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The short version

Turns out, some cuckoos are more cunning than you'd think, using dummy eggs to get the job done
This isn't a random trick.
To keep the "parents" working, the single cuckoo chick can mimic the begging calls of an entire brood of hungry babies.

A common cuckoo doesn't just drop an egg and leave; it performs a high-speed heist. To ensure the egg is accepted, the female cuckoo mimics the appearance of a hawk to scare the resident bird away from the nest.

While the host bird hides from what it thinks is a predator, the cuckoo swoops in and replaces one of the original eggs with her own in less than ten seconds. Her eggs are biological forgeries, evolved to match the exact color, speckling, and size of the host bird’s species.

This isn't a random trick. Individual cuckoos belong to specific genetic lines called gentes, where each line specializes in mimicking one specific host bird, like a meadow pipit or a reed warbler. A cuckoo raised by a warbler will grow up to lay eggs that look exactly like warbler eggs.

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