Kosher animals are animals that comply with the regulations ofkashrut and are consideredkosher foods. These dietary laws ultimately derive from various passages in theTorah with various modifications, additions and clarifications added to these rules byhalakha. Various other animal-related rules are contained in the613 commandments.

Leviticus 11:3–8 andDeuteronomy 14:4–8 both give the same general set of rules for identifying which land animals (Hebrew: בהמותBehemoth) areritually clean. According to these, any animal which "chews the cud" (e.g., consumes vegetation and later regurgitates it into the mouth to be re-processed and more efficiently digested) and has acompletely split hoof (cloven-foot) is ritually clean, but those whichonly chew the cud oronly have cloven hooves are unclean.

Both documents explicitly list four animals as being ritually impure:

• Thecamel, for chewing the cud without its hooves being divided.^[1][2]
• Thehyrax, for chewing the cud without having cloven hooves;^[2][3] as the hyrax was not known to early English translators, the Hebrew term for this animal, שפן (shapan), has been interpreted in older English versions of the Bible asconey (rabbit, hare), a name with clear connections to words such as theSpanishconejo (rabbit). The actual coney was an exclusively Europeanlagomorph, and not present inCanaan; hyraxes, however, are still found inSouthern andEastern Africa, theLevant andArabian Peninsula, with theshapan in theBook of Proverbs described as having lived on rocks^[4] (likely referring to therock hyrax, not the coney). Despite their rabbit- orrodent-like appearance, hyraxes are actually one of the closest living relatives ofelephants, still possessing "tusk"-like teeth—as opposed to the ever-growing, gnawing teeth of rodents or lagomorphs. Additionally, their feet do not have the small claws and digits of rodents or lagomorphs, instead resembling miniature elephant-feet, with toenails specially adapted for climbing rocks.

• Thehare, for chewing the cud without having cloven hooves.^[2][5]
• Thepig, for having cloven hooves without chewing the cud.^[6][7]

While camels possess a single stomach, and are thusnot true ruminants, they dochew cud; additionally, camels do not have hooves at all, but rather separate toes on individual toe pads, with hoof-like toenails.

Although hares and other lagomorphs (coney, rabbits,pikas) do not ruminate at all, they do typically re-ingestsoft cecal pellets made of chewed plant material immediately after excretion for further bacterial digestion in their stomach, which serves the same purpose as rumination. They are also known to ingest their own and the droppings of other lagomorphs for nutritive reasons.

Although not ruminants, hyraxes have complex, multichambered stomachs that allow symbiotic bacteria to break-down tough plant materials, though they do not regurgitate it for re-chewing.^[8] Further clarification of this classification has been attempted by various authors, most recently by RabbiNatan Slifkin, in a book, entitledThe Camel, the Hare, and the Hyrax.^[9]

UnlikeLeviticus 11:3-8,Deuteronomy 14:4-8 also explicitly names 10 animals considered ritually clean:

• Theox^[10]
• Thesheep^[10]
• Thegoat^[10]
• Thedeer^[11]
• Thegazelle^[11]
• Theyahmur;^[11] this term, directly taken from theMasoretic Text, is used by Arabs to refer toroe deer^[12]
• Thethe'o;^[11] this term, directly taken from the Masoretic Text, has traditionally been translated ambiguously.
   

In Deuteronomy, it has traditionally been translated aswild goat, but in the same translations is called awildox where it occurs inIsaiah;^[13] thebubal hartebeest lies somewhere between these creatures in appearance and has been regarded as a likely fit forthe'o.

• Thepygarg;^[11] the identity of this animal is uncertain, andpygarg is merely theSeptuagint's rendering.
   

The Masoretic Text calls it adishon, meaningspringing; it has thus usually been interpreted as some form ofantelope oribex.

• Theantelope^[11]
• Thecamelopardalis;^[11] the identity of this animal is uncertain, and "camelopardalis" is merely the Septuagint's wording.^[14] The Masoretic Text calls it azamer, butcamelopardalis meanscamel-leopard and typically refers to thegiraffe (giraffe is derived, viaItalian, from theArabic termziraafa, meaning "assembled [from multiple parts]"); intaxonomy, several types of giraffes are placed underGiraffa camelopardalis. The traditional translation has been for thechamois, an alpinegoat-antelope of Europe and parts ofAsia Minor, but it has never naturally existed in Canaan; neither is the giraffe naturally found in Canaan (though it was likely known fromNorthern Africa). Consequently, the wild sheep ancestor, themouflon, is considered the best remaining identification, despite not being related to the term "camel-leopard".

The Deuteronomic passages mention no further land beasts as being clean or unclean, seemingly suggesting that the status of the remaining land beasts can be extrapolated from the given rules.

By contrast, the Levitical rules later go on to add that allquadrupeds withpaws should be considered ritually unclean,^[15] something not explicitly stated by the Deuteronomic passages.

The Leviticus passages thus cover all the large land animals that naturally live inCanaan, except forprimates, andequids (horses,zebras, etc.), which are not mentioned in Leviticus as being either ritually clean or unclean, despite their importance in warfare and society, and their mention elsewhere in Leviticus.

In an attempt to help identify animals of ambiguous appearance, theTalmud, in a similar manner toAristotle's earlierHistoria Animalium,^[16] argued that animals without upper teeth would always chew the cud and have split hoofs (thus being ritually clean), and that no animal with upper teeth would do so; the Talmud makes an exception for the case of the camel (which, like the other ruminant even-toed ungulates, is apparently 'without upper teeth' though some citations^[17]), even though the skulls clearly have both front and rear upper teeth. The Talmud also argues that the meat from the legs of clean animals can be torn lengthwise as well as across, unlike that of unclean animals,^{[unreliable source?]} thus aiding to identify the status of meat from uncertain origin.^[17]

Many Biblical scholars believe that the classification of animals was created to explain pre-existingtaboos.^[18] Beginning withSaadia Gaon, several Jewish commentators started to explain these taboos rationalistically; Saadia himself expresses an argument similar to that oftotemism, that the unclean animals were declared so because they were worshipped by other cultures.^[19] Due to comparatively recent discoveries about the cultures adjacent to the Israelites, it has become possible to investigate whether such principles could underlie some of the food laws.

Egyptian priests would only eat the meat ofeven-toed ungulates (swine, camelids, and ruminants), and rhinoceros.^[20] Like the Egyptian priests,Vedic India (and presumably thePersians also) allowed the meat ofrhinoceros and certain ruminants, although cattle were likely excluded asthey were seemingly taboo in Vedic India;^[21][22][23] in a particular parallel with theIsraelite list, Vedic India explicitly forbade the consumption of camelids and domestic pigs (but notwild boar).^[21][22][23] However, unlike the biblical rules, Vedic India did allow the consumption of hare andporcupine,^[21][22][23] butHarran did not, and was even more similar to the Israelite regulations, allowing all ruminants (but not other land beasts) and expressly forbidding the meat of camels.^[17][24]

It is also possible to find an ecological explanation for these rules. If one believes that religious customs are at least partly explained by the ecological conditions in which a religion evolves, then this too could account for the origin of these rules.^[25]

In addition to meeting the restrictions as defined by theTorah, there is also the issue ofmasorah (tradition). In general, animals are eaten only if there is amasorah that has been passed down from generations ago that clearly indicates that these animals are acceptable. For instance, there was considerable debate as to the kosher status ofzebu andbison among the rabbinical authorities when they first became known and available for consumption; theOrthodox Union permitsbison,^[26] as can be attested to by the menus of some of the more upscale kosher restaurants inNew York City^{[citation needed]}.^[27]

Leviticus 11:9–12 andDeuteronomy 14:9–10 both state that anything residing in "the waters" (which Leviticus specifies as being the seas and rivers) is ritually clean if it has bothfins andscales,^[28][29] in contrast to anything residing in the waters with neither fins nor scales.^[30][31] The latter class of animals is described as ritually impure by Deuteronomy,^[31] Leviticus describes them as an "abomination" KJV Leviticus 11:10. Abomination is also sometimes used to translateiggul andtoebah.

Although the Old Testament does not further specify, theTalmud makes the claim that all fish that have scales also have fins,^[32] and so practically speaking, we need to only identify organisms that have scales and can ignore the portion of the rule about fins.Nachmanides comments that the scales of a kosher fish must be able to be removed either by hand or by knife, but that the underlying skin does not become damaged with removal of the scales,^[33] and this opinion had been universally accepted by allhalachic authorities at the time.^[34]

Scientifically, there are five different types offish scales:placoid,cosmoid,ganoid,ctenoid andcycloid. The majority of kosher fish exhibit the latter two forms, ctenoid or cycloid, but thebowfin (Amia calva) is an example of a fish with ganoid scales that is deemed kosher. As such, kosher status cannot be said to follow the rules of modern-day classification, and qualified experts on kosher fish must be consulted to determine the status of a particular fish or scale type.^[35]

These rules restrict permissibleseafood to stereotypical fish, prohibiting the unusual forms such as theeel,lamprey,hagfish, andlancelet. In addition, they exclude non-fish marine creatures, such ascrustaceans (lobster,crab,prawn,shrimp,barnacle, etc.),molluscs (squid,octopus,oyster,periwinkle, etc.),sea cucumbers, andjellyfish.

Other creatures living in the sea and rivers that would be prohibited by the rules include thecetaceans (dolphin,whale, etc.),crocodilians (alligator,crocodile etc.),sea turtles,sea snakes, and allamphibians.

Sharks are considered to be ritually unclean according to these regulations, as their scales can only be removed by damaging the skin. Aminor controversy arises from the fact that the appearance of the scales ofswordfish is heavily affected by the ageing process—their young satisfy Nachmanides' rule, but when they reach adulthood they do not.

Traditionally "fins" has been interpreted as referring totranslucent fins. TheMishnah claims that all fish withscales will also have fins, but that the reverse is not always true.^[36] For the latter case, the Talmud argues that ritually clean fish have a distinct spinal column and flattish face, while ritually unclean fish don't have spinal columns and have pointy heads,^[37] which would define the shark and sturgeon (and related fish) as ritually unclean.

Nevertheless,Aaron Chorin, a prominent 19th-century rabbi and reformer, declared that the sturgeon was actually ritually pure, and hence permissible to eat.^[17] ManyConservative rabbis now view these particular fish as being kosher,^[38] but mostOrthodox rabbis do not.^[34]

The question for sturgeon is particularly significant as mostcaviar consists of sturgeon eggs, and therefore cannot be kosher if the sturgeon itself is not. Sturgeon-derived caviar is not eaten by some Kosher-observant Jews because sturgeon possess ganoidscales instead of the usual ctenoid and cycloid scales. There is akosher caviar.^[39]Atlantic salmon roe is alsokosher.^[40]

Nachmanides believed that the restrictions against certain fish also addressed health concerns, arguing that fish with fins and scales (and hence ritually clean) typically live in shallower waters than those without fins or scales (i.e., those that were ritually impure), and consequently the latter were much colder and more humid, qualities he believed made their flesh toxic.^[41]

The academic perception is that natural repugnance from "weird-looking" fish is a significant factor in the origin of the restrictions.^{[42][43][44][45][46]} Vedic India (and presumably the Persians also) exhibit such repugnance, generally allowing fish, but forbidding "weird looking" fish and exclusively carnivorous fish;^[21][22][23] in Egypt, another significant and influential culture near to the Israelites, the priests avoided all fish completely.^[20]

With regard to birds, no general rule is given, insteadLeviticus 11:13–19 andDeuteronomy 14:11–18 explicitly list prohibited birds. In theShulchan Aruch, 3 signs are given tokosher birds: the presence of acrop, an extra finger, and a gizzard that can be peeled. The bird must also not be abird of prey. The Masoretic Text lists the birds as:

The list in Deuteronomy has an additional bird, thedayyah,^[49] which seems to be a combination of'da'ah' and'ayyah', and may be ascribal error; theTalmud regards it as a duplication ofayyah.^[61] This, and the other terms, are vague and difficult to translate, but there are a few further descriptions, of some of these birds, elsewhere in the Bible:

• Theayyah is mentioned again in theBook of Job, where it is used to describe a bird distinguished by its particularly good sight.^[62]
• Thebat yaanah is described by theBook of Isaiah as living in desolate places,^[63] and theBook of Micah states that it emits a mournful cry.^[64]
• Theqa'at appears in theBook of Zephaniah, where it is portrayed as nesting on the columns of a ruined city;^[65] theBook of Isaiah identifies it as possessing a marshy and desolate kingdom.^[66]

TheSeptuagint versions of the lists are more helpful, as in almost all cases the bird is clearly identifiable:

Although the first 10 birds identified by the Septuagint seem to fit the descriptions of the Masoretic Text, the ossifrage (Latin for "bone breaker") being a good example, the correspondence is less clear for most of the remaining birds.

It is also obvious that the list in Leviticus, or the list in Deuteronomy, or both, are in a different order in the Septuagint, compared to the Masoretic Text.^[a]

Attempting to determine the correspondence is problematic; for example, "pelican" may correspond toqa'at ("vomiting"), in reference to the pelican's characteristic behaviour, but it may also correspond tokos ("cup"), as a reference to the pelican's jaw pouch.

An additional complexity arises from the fact that theporphyrion has not yet been identified, and classical Greek literature merely identifies a number of species that are not theporphyrion, including thepeacock,grouse, androbin, and implies that theporphyrion is the cousin of thekingfisher. From these meager clarifications, theporphyrion can only be identified as anything from thelilac-breasted roller,Indian roller, ornorthern carmine bee-eater, to theflamingo. A likely candidate is thepurple swamphen.^{[according to whom?]}

During the Middle Ages, classical descriptions of the hoopoe were mistaken for descriptions of thelapwing, on account of the lapwing's prominent crest, and the hoopoe's rarity in England, resulting in "lapwing" being listed in certain bible translations instead of "hoopoe".

Similarly, the sea eagle has historically been confused with theosprey, and translations have often used the latter bird in place of the former. Becausestrouthos (ostrich) was also used in Greek for thesparrow, a few translations have placed the sparrow among the list.

InArabic, theEgyptian vulture is often referred to asrachami,^[82] and therefore a number of translations render'racham' as "gier eagle", the old name for the Egyptian vulture.

Variations arise when translations follow other ancient versions of the Bible, rather than the Septuagint, where they differ. Rather than vulture (gyps), theVulgate has"milvus", meaning "red kite", which historically has been called the "glede", on account of its gliding flight; similarly, theSyriac Peshitta has "owl" rather than "ibis".

Other variations arise from attempting to base translations primarily on the Masoretic Text; these translations generally interpret some of the more ambiguous birds as being various different kinds of vulture and owl. All of these variations mean that most translations arrive at a list of 20 birds from among the following:

Despite being listed among the birds by the Bible, bats are not birds, and are in factmammals (because the Hebrew Bible distinguishes animals into four general categories—beasts of the land, flying animals, creatures which crawl upon the ground, and animals which dwell in water—not according to modern scientific classification).

Most of the remaining animals on the list are eitherbirds of prey or birds living on water, and the majority of the latter in the list also eat fish or other seafood.

The Septuagint's version of the list comprehensively lists most of the birds of Canaan that fall into these categories. The conclusion of modern scholars is that, generally, ritually unclean birds were those clearly observed to eat other animals.^[83]

Although it does regard all birds of prey as being forbidden, the Talmud is uncertain of there being a general rule, and instead gives detailed descriptions of the features that distinguish a bird as being ritually clean.

The Talmud argues that clean birds would havecraws, an easily separated 'double-skin', and would eat food by placing it on the ground (rather than holding it on the ground) and tearing it with their bills before eating it;^[84][85][86] however, the Talmud also argues that only the birds in the biblical list are actually forbidden—these distinguishing features were only for cases when there was any uncertainty in the bird's identity.^[86]

The earliest rationalistic explanations of the laws against eating certain birds focused on symbolic interpretations. The first indication of this view can be found in the 1st century BCLetter of Aristeas, which argues that this prohibition is a lesson to teach justice, and is also about not injuring others.^[87]

Such allegorical explanations were abandoned by most Jewish and Christian theologians after a few centuries, and later writers instead sought to find medical explanations for the rules; Nachmanides, for example, claimed that the black and thickened blood of birds of prey would cause psychological damage, making people much more inclined to cruelty.^[41]

However, other cultures treated the meat of certain carnivorous birds as having medical benefits, theRomans viewing owl meat as being able to ease the pain of insect bites.

Conversely, modern scientific studies have discovered very toxic birds such as thepitohui, which are neither birds of prey nor water birds, and therefore the biblical regulations allow them to be eaten.

Laws against eating any carnivorous birds also existed in Vedic India^[21][22][23] and Harran,^[17][24] and the Egyptian priests also refused to eat carnivorous birds.^[20]

Due to the difficulty of identification, religious authorities have restricted consumption to specific birds for which Jews have passed down a tradition of permissibility from generation to generation. Birds for which there has been a tradition of their being kosher include:

As a general principle, scavenging birds such asvultures andbirds of prey such ashawks andeagles (which opportunistically eatcarrion) are unclean.

Theturkey^[89] does not have a tradition, but because so many Orthodox Jews have come to eat it and it possesses thesimanim (signs) required to render it a kosher bird, an exception is made, but with all other birds amasorah is required.

Songbirds, which are consumed as delicacies in many societies, may be kosher in theory, but are not eaten in kosher homes as there is no tradition of them being eaten as such.Pigeons anddoves are known to be kosher^[91] based on their permissible status as sacrificial offerings in theTemple of Jerusalem.

TheOrthodox Union of America considers neither thepeafowl nor theguineafowl to be kosher birds^[88] since it has not obtained testimony from experts about the permissibility of either of these birds. In the case of theswans, there is no clear tradition of eating them.^[94]

RabbiChaim Loike is currently the Orthodox Union's specialist on kosher bird species.^[95]

Unlike with land creatures and fish, theTorah does not give signs for determining kosher birds, and instead gives a list of non-kosher birds.

The Talmud also offers signs for determining whether a bird is kosher or not.

If a bird kills other animals to get its food, eats meat, or is a dangerous bird, then is not kosher, a predatory bird is unfit to eat, raptors like the eagles,hawks,owls and other hunting birds are not kosher,vultures and other carrion-eating birds are not kosher either.^[96]

Crows and members of thecrow family such as jackdaws, magpies and ravens are not kosher.^{[citation needed]}Storks, kingfishers,penguins and other fish-eating birds are not kosher.^[96]

Deuteronomy 14:19 specifies that all "flying creeping things" were to be considered ritually unclean^[97] andLeviticus 11:20 goes further, describing all flying creeping things as filth, Hebrewsheqets.^[98] Leviticus goes on to list four exceptions, which Deuteronomy does not.

All these exceptions are described by the Levitical passages as "going upon all four legs" and as having "legs above their feet" for the purpose of leaping.^[99] The identity of the four creatures the Levitical rules list are named in the Masoretic Text using words of uncertain meaning:

• arbeh^[100]—the Hebrew word literally means "[one which] increases". The Septuagint calls it abrouchos, referring to a wingless locust, and older English translations render this asgrasshopper in most parts of the Bible, but inconsistently translate it aslocust in Leviticus.^[101]
   

In theBook of Nahum, thearbeh is poetically described as camping in hedges in cold days, but flying off into the far distance when the sun arises;^[102] for this reason, a number of scholars have suggested that thearbeh must actually be themigratory locust.^[14]

• sol'am^[100]—the Hebrew term literally means "swallower". TheSeptuagint calls it anattacos, the meaning of which is currently uncertain. TheTalmud describes it as having a long head that is bald in front,^[103][104] for which reason a number of English translations call it a bald locust (an ambiguous term); many modern scholars believe that theAcrida (previously calledTryxalis) is meant, as it is distinguished by its very elongated head.
• hargol^[100]—the Hebrew term literally meansstrafer (one that runs to the right or to the left). The Septuagint calls it anophiomachos, literally meaning "snake fighter"; the Talmud describes it as having a tail.^[105] The Talmud also states that it has large eggs, which were turned intoamulets.^[106] This has historically been translated asbeetle, but since the 19th century,cricket has been deemed more likely to fit.
• hagab^[100]—the word literally means "hider". TheBook of Numbers implies that they were particularly small.^[107] The Septuagint calls it anakrida, and it has usually been translated as grasshopper.

The Mishnah argues that the ritually clean locusts could be distinguished as they would all have four feet, jumping with two of them, and have four wings which are of sufficient size to cover the entire locust's body.^[108] The Mishnah also goes on to state that any species of locust could only be considered as clean if there was a reliable tradition that it was so.

The only Jewish group that continue to preserve such a tradition are theJews of Yemen, who use the term "kosher locust" to describe the specific species of locusts they believe to be kosher, all of which are native to theArabian Peninsula.

Due to the difficulties in establishing the validity of such traditions, laterrabbinical authorities forbade contact with all types of locust^[109] to ensure that the ritually unclean locusts were avoided.^[110]

Leviticus 11:42–43 specifies that whatever "goes on its belly, and whatever goes on all fours, or whatever has many feet, any swarming thing that swarms on the ground, you shall not eat, for they are detestable." (Hebrew:sheqets). Before stating this, it singles out eight particular "creeping things" as specifically being ritually unclean inLeviticus 11:29–30.^[111]

Like many of the other biblical lists of animals, the exact identity of the creatures in the list is uncertain; medieval philosopher and RabbiSaadia Gaon, for example, gives a somewhat different explanation for each of the eight "creeping things." The Masoretic Text names them as follows:

• holed^[112]—the Talmud describes it as a predatory animal^[113] that bores underground.^{[114][115][116]}
• akhbar^[112]—inArabic, thecognate word,akhbar, refers to thejerboa
• tzab^[117]—the Talmud describes it as being similar to asalamander^[118]
• anaqah^[112]—this Hebrew term literally means "groaner", and consequently a number of scholars believe it refers to agecko, which makes a distinctive croaking sound.
• ko'ah^[117]
• leta'ah^[117]—the Talmud describes it as being paralyzed by heat but revived with water, and states that its tail moves when cut off^[119]
• homet^[117]
• tinshemet^[117]—this term literally means "blower/breather", and also appears in the list of birds

The Septuagint version of the list does not appear to directly parallel the Masoretic, and is thought to be listed in a different order. It lists the eight as:

• galei—a general term including theweasel,ferret, and thestoat, all of which are predatory animals noticeably attracted to holes in the ground.
• mus—themouse.
• krokodelos-chersaios—the "land crocodile", which is thought to refer to themonitor lizard, a large lizard of somewhat crocodilian appearance.
• mygale—theshrew.
• chamaileon—thechameleon, which puffs itself up and opens its mouth wide when threatened
• chalabotes—a term derived fromchala meaning "rock/claw", and therefore probably thewall lizard^{[citation needed]}
• saura—thelizard in general, possibly here intended to be theskink, since it is the other remaining major group of lizards.
• aspalax—the mole-rat, although some older English translations, not being aware of the mole-rat's existence, have instead translated this asmole.
• Theearthworm, thesnake, thescorpion, thebeetle, thecentipede, and all the creatures that crawl on the ground are not kosher.^[120][121]
• Worms,snails and mostinvertebrate animals are not kosher.^[122][121]
• Allreptiles, allamphibians andinsects with the exception of four types oflocust are not kosher.^[122]

• Kashrut
• Kosher foods