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The animal on the cover of Feature Engineering for Machine Learning is a pharaoh eagle-owl (Bubo ascalaphus). This bird of prey is found in Northern Africa and the Arabian peninsula in rocky, arid habitat. It is among the smaller eagle-owls at 18–20 inches long, though the Bubo genus contains some of the largest owl species. Most eagle-owls (as well as their American cousins, horned owls) have distinctive ear tufts.

The pharaoh eagle-owl is nocturnal and hunts with a perching method. From a high vantage point, it waits for small mammals, snakes, lizards, birds, and even insects to come into range, before swiftly swooping toward its prey. It is well equipped for this with keen farsightedness and hearing, feathers optimized for silent flight, and sharp talons. Owls can also turn their heads in a range of about 270 degrees, allowing them to look behind themselves without making much movement.

This species has mottled brown, black, and white plumage, and distinctive orange-yellow eyes. Pharaoh owls are known to mate for life. Nesting sites are created in shallow scrapes among rocks, within crevices, or (occasionally) manmade structures like wells. In Egypt, the owls have been seen nesting on the pyramids.

Many of the animals on O’Reilly covers are endangered; all of them are important to the world. To learn more about how you can help, go to animals.oreilly.com.

The cover image is from Elements of Ornithology. The cover fonts are URW Typewriter 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.