Archive: https://archive.today/gk4me From the post: >>More than 20 species of bird around the world use a similar “whining” alarm call to warn birds like cuckoos are around. The call seems to be understood across species, and its specific use hints at how language may have originated. Cuckoos are one of a range of some 100 species known as brood parasites that lay their eggs in the nests of other birds, attempting to con the hosts into incubating and caring for the hatchlings as if they were the hosts’ own offspring.