Crow
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American Crow
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Scientific classification | |||||||||||||
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Species
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See text. |
The true crows are in the genus Corvus; they are large passerine birds. All temperate continents (except South America) and several offshore and oceanic islands (including Hawaii) have representatives of the 40 or so members of this genus.
Crows in the genus (Corvus) appear to have evolved in central Asia and radiated out into North America (including Mexico), Africa, Europe, and Australia.
The latest evidence appears to point towards an Australasian origin for the early family (Corvidae) though the branch that would produce the modern groups such as Jays, Magpies and Large predominantly black Corvus Crows had left Australasia and were now developing in Asia. Corvus has since re-entered Australia (relatively recently) and produced five species with one recognised sub-species.
They range in size from the relatively small pigeon-sized jackdaws ( Eurasian and Daurian) to the Common Raven of the Palearctic region and Thick-billed Raven of the highlands of Ethiopia.
Traditionally, the collective noun for a group of crows is a murder, and a group of ravens is called an unkindness. However, in practice most people, and especially scientists, use the more generic term flock.
Color and society
Extra-specific uses of colour in crow societies
Many crow species are all black. Most of their natural enemies, the raptors or "falconiformes", soar high above the trees, and hunt primarily on bright, sunny days when contrast between light and shadow is greatest. Crows take advantage of this by maneuvering themselves through the dappled shades of the trees, where their black colour renders them effectively invisible to their enemies above, in order to set up complex ambush attacks. Thus, their black "colour" is of great military importance to their societies. (It is perhaps here where we find the greatest difference between ravens and other crows; ravens tend to soar high in the air as raptors do, and like raptors, are usually the target of ambushes by other crows. Non-ravenous crows do not appear to perceive ravens as their own kind, but instead treat them as raptors.)
Intra-specific uses of colour in crow societies
Even in species characterized by being all black, one will still occasionally find variations, most of which appear to result from varying degrees of albinism, such as:
- an otherwise all-black crow stunningly contrasted by a full set of brilliant, pure-white primary feathers.
- complete covering in varying shades of grey (generally tending toward the darker side)
- blue or red, rather than swarthy eyes (blue being more common than red).
- Some combination of the above
The treatment of these rare individuals may vary from group to group, even within the same species. For example, one such individual may receive special treatment, attention, or care from the others in its group, while another group of the same species might exile such individuals, forcing them to fend for themselves. The reason for such behaviors, and why these behaviors vary as they do, has yet to be studied.
Mythology and folklore
Crows, and especially ravens, often feature in legends or mythology as portents or harbingers of doom or death, because of their dark plumage, unnerving calls, and tendency to eat carrion. They are commonly thought to circle above scenes of death such as battles.
In Native American folklore, Crow is often seen as a similar trickster to Coyote. However, Crow's tricks tend to be more out of maliciousness and he rarely (if ever) is portrayed as a hero. One possible explanation for this is that crows are often considered a pest to crops, which the tribes who came up with the stories featuring Crow needed to survive.
In the Epic of Gilgamesh, the Chaldean myth, the character Utnapishtim releases a dove and a raven to find land, similar to what Noah does in the book of Genesis. However, in the Epic of Gilgamesh, the dove merely circles and returns. Only then does Utnapishtim send forth the raven, who does not return. Utnapishtim extrapolates from this that the raven has found land, which is why it hasn't returned. This would seem to indicate some acknowledgement of crow intelligence, which may have been apparent even in ancient times, and to some might imply that the higher intelligence of crows, when compared to other birds, is striking enough that it was known even then.
In occult circles, distinctions are sometimes made between crows and ravens. In mythology and folklore as a whole, crows tend to be symbolic more of the spiritual aspect of death, or the transition of the spirit into the afterlife, whereas ravens tend more often to be associated with the negative (physical) aspect of death. However, few if any individual mythologies or folklores make such a distinction, and there are ample exceptions. Another reason for this distinction is that while non-ravenous crows are typically highly social animals, ravens don't seem to congregate in large numbers anywhere but a) near carrion where they meet seemingly by chance, or b) at cemeteries, where large numbers sometimes live together, even though carrion there is no more available (and probably less attainable) than any road or field.
Amongst Neopagans, crows are often thought to be highly psychic and are associated with the element of ether or spirit, rather than the element of air as with most other birds. This may in part be due to the long-standing occult tradition of associating the colour black with "the abyss" of infinite knowledge (see akasha), or perhaps also to the more modern occult belief that wearing the "colour" black aids in psychic ability, as it absorbs more electromagnetic energy, since surfaces appear black by absorbing all frequencies in the visible spectrum, reflecting no colour.
Gods and goddesses associated or identified with crows and ravens
A very incomplete list includes the eponymous Pacific Northwest Native figures Raven and Crow, the ravens Hugin and Munin, who accompany the Norse god Odin, the Celtic goddesses the Mórrígan and/or the Badb (sometimes considered separate from Mórrígan), and Shani, a Hindu god who travels astride a crow.
Intelligence
As a group, the crows show remarkable examples of intelligence. They top the avian IQ scale [1]. Crows and ravens often score very highly on intelligence tests. Crows in the northwestern US (a blend of Corvus brachyrhynchos and Corvus caurinus) show modest linguistic capabilities and the ability to relay information over great distances, live in complex, hierarchic societies involving hundreds of individuals with various "occupations", and have an intense rivalry with the area's less socially-advanced ravens. One species, the New Caledonian Crow, has recently been intensively studied because of its ability to manufacture and use its own tools in the day-to-day search for food. Wild hooded crowsin Israel, learned to use bread crumbs for bait-fishing.
Species
Australian species
- Australian Raven C. coronoides
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Forest Raven C. tasmanicus
- Relict Raven C. t. boreus
- Little Crow C. bennetti
- Little Raven C. mellori
- Torresian Crow C. orru
North American species
- American Crow C. brachyrhynchos
- Chihuahuan Raven C. cryptoleucus
- Common Raven C. corax
- Fish Crow C. ossifragus
- Northwestern Crow C. caurinus
- Tamaulipas Crow C. imparatus
- Sinaloan Crow C. sinaloae
African species
- Cape Crow C. capensis
- Fan-tailed Raven C. rhipidurus
- Pied Crow C. albus
- Somali Crow or Dwarf Raven C. edithae
- Thick-billed Raven C. crassirostris
- White-necked Raven C. albicollis
North African and Asia Minor species
- Brown-necked Raven C. ruficollis
- Hooded Crow C. cornix
- Common Raven C. corax
- Fan-tailed Raven C. rhipidurus
European species
- Carrion Crow C. corone
- Common Raven C. corax
- Hooded Crow C. cornix
- Jackdaw C. monedula
- Rook C. frugilegus
Asian species
- Carrion Crow C. corone
- Collared Crow C. torquatus
- Daurian Jackdaw C. dauricus
- House Crow C. splendens
- Jungle Crow C. macrorhynchos
- Rook C. frugilegus
- Common Raven C. corax
The islands between Southeast Asia and Australia have several species, as do the West Indies off the south east coast of the North American continent. A few Pacific islands (including Hawaii) have representative species also.
- Hawaiian Crow or 'Alala C. hawaiiensis (formerly C. tropicus)
- New Caledonian crow C. moneduloides
- Cuban Crow C. nasicus
- Jamaican Crow C. jamaicensis
- Palm Crow C. palmarum
- White-necked Crow C. leucognaphalus
- White-billed Crow C. woodfordi
- Grey Crow C. tristis
For more information regarding crows, see the individual species.
For more information regarding relatives of the crows, such as magpies and jays, see Corvidae.