To someone watching birds casually, the cuckoo’s behaviour looks almost lazy. Instead of gathering twigs, lining a nest, and feeding its chicks, the cuckoo quietly slips its egg into another bird’s ...

Clever birds figure out how to trick others into raising their kids A common Cuckoo chick in Reed Wablers nest waits to be fed with its mouth wide open, in this undated file photo. Getty Images — ...