Crow

Lots of non-human animals, including chimpanzees and orangutans, create useful implements which help them survive in the wild. The New Caledonian crow (Corvus moneduloides) is one of only two species on the planet that can craft its own hooks in the wild. The other is called Homo sapiens. The South Pacific avian uses the hooks—which are made from pliable twigs that the crows bend using their beaks and feet into a J-shape—to extract insects from tight crevices.

Another surprising attribute is this species' bill. Unlike virtually all other birds, the New Caledonian crow has a bill that does not curve downwards. For years, the quirk went unexplained, but scientists now think that the avian's unique beak evolved to help it grasp tools more easily, as well as to better see what the tool is doing.

The New Caledonian crow isn't the only implement expert in the corvid family. In 2016, scientists at the University of St. Andrews demonstrated that the ultra-rare Hawaiian crow, or ‘Alalā (Corvus hawaiiensi

Since the 1990s, crows have experienced a population boom in Japan, where—not coincidentally—delicious garbage is more plentiful than ever before. This is bad news for power companies. Urban crows like to nest on electric transformers and will often use wire hangers or fiber-optic cables as building materials for their nests. The result was an epidemic of crow-caused blackouts in major cities around Japan: Between 2006 and 2008, the corvids stole almost 1400 fiber-optic cables from Tokyo power providers, and according to the Chubu electric company, crows are responsible for around 100 power failures per year in their facilities alone.

To fight back, Chubu started installing artificial "love nests" in 2004. Made with non-conductive resin, the nests are placed on company towers high above the power lines, where the birds are unlikely to cause any trouble. The strategy seems to be working: 67 percent of the faux nests are currently in use, making life a lot easier for Chubu employees.

The sight of a dead crow tends to attract a mob of a hundred or more live ones. During this ritual, the live crows almost never touch the dead one, which rules scavenging out as a motive. Why do they do this? Some studies suggest that the mass gathering is part of a survival strategy: The birds are learning about threats and seem hesitant to revisit any spot where they've encountered a dead crow, even if food is plentiful there.

Members of the genus Corvus can be found on every continent except Antarctica and South America (although other close relatives live there). To date, scientists have named 40 species. Colloquially, some of them are referred to as ravens while others are called crows, rooks, or jackdaws.

Historically, the name raven has been given to several of the big-bodied Corvus birds with shaggy feathers on their necks. Mid-sized members of the genus are usually called crows, while the very smallest species go by the name jackdaws. There's also a large-beaked outlier known as the rook, which was named after the unusual sound it makes. But pervasive as these labels may be, they're not scientific and do not reflect the latest research. Despite its informal name, the so-called Australian raven is more closely akin to the Torresian crow than it is to the common raven.

In the U.S., when people talk about crows and ravens, they're usually referring to the American crow (Corvus brachyrhynchos) and the common raven (Corvus corax). Telling them apart can be tough, but it is possible for eagle-eyed birders. One big indicator is size: The common raven is much larger, about the size of a red-tailed hawk. It also has a more wedge-shaped tail. As Kevin J. McGowan of the Cornell Lab of Ornithology writes on his crow FAQ page, ravens soar longer than crows, and you can see through their wing feathers as they fly (among other differences). And the birds' calls are substantially different. "American crows make the familiar caw-caw, but also have a large repertoire of rattles, clicks, and even clear bell-like notes," McGowan writes, whereas common ravens have "a deep, reverberating croaking or gronk-gronk. Only occasionally will a raven make a call similar to a crow's caw, but even then it is so deep as to be fairly easily distinguished from a real crow."