The animal on the cover of Learning JavaScript Design Patterns is the cuckoo pheasant (Dromococcyx phasianellus, also known as the pheasant cuckoo). The pheasant cuckoo is a bird that is native to forests from the Yucatan peninsula to Brazil and may be found as far south as Colombia.
The pheasant cuckoo has a long tail and a short, dark-brown crest. Its diet consists of insects, which it catches by making rattling sounds with its feathers and clapping its bill, then running several steps forward and pecking at the ground. Although it is an insectivore, it may also feed on small lizards and nestlings.
Like many other cuckoos, the pheasant cuckoo lays its eggs in another bird’s nest. When the eggs hatch, the adoptive mother will recognize the cuckoo’s offspring as her own, and the hatchlings will imprint on their adoptive mother. Acting on instinct, cuckoo hatchlings will push the host parent’s eggs out of the nest to make room for themselves. Unlike the European cuckoo, however, the pheasant cuckoo is not an obligate brood parasite; it still has the ability to construct nests of its own.
The current conservation status (IUCN) of the pheasant cuckoo is “Least Concern.” Many of the animals on O’Reilly covers are endangered; all of them are important to the world.
The cover illustration is by Karen Montgomery, based on a loose plate engraving, origin unknown. The cover fonts are Gilroy Semibold and Guardian Sans. The text font is Adobe Minion Pro; the heading font is Adobe Myriad Condensed; and the code font is Dalton Maag’s Ubuntu Mono.