> Controversy: Literal, or Figurative? > Cosmological Hierarchy > Nāgas > Supannas > Causes of Animal Rebirth
In this essay, I will explore the possibility of rebirth as an animal as discussed in the early Buddhist texts. There are many stories which tell of past animal existences of the Buddha and important disciples. In the Pali Canon, such stories are found in the "Jātakatthavannanā," a portion of the Khuddaka Nikaya. I will not be including these in this essay - many of these are relatively late additions to the canon, and are more narrative than cosmological in content. Instead, this essay will be limited to establishing the nature of animal existence in the Buddhist framework of rebirth.1
『I ain't readin' this whole dang page! 』
Here are the highlights:
1. When the suttas discuss rebirth as an animal, this is not a metaphor.
2. Within the cosmological hierarchy, animal existence is the second lowest "destination" of rebirth.
3. Animal existence is the most diverse type of rebirth in Buddhist cosmology, with two notable outliers: the mythical nāgas and supannas.
4. The suttas discuss various kinds of kamma that produce existence as the various types of animals, further revealing the diversity within animal existence.
Elsewhere, I have argued against the misconception that the general idea of rebirth in Buddhism is an elaborate metaphor for states of mind. Some skeptics focus specifically on passages about rebirth as animals, insisting they should be interpreted figuratively, even if they accept the reality of rebirth otherwise. While my arguments against broad rebirth-skepticism certainly apply to more pointed denials of animal rebirth specifically, I think I should use this space to provide similarly pointed refutations of claims denying the reality of rebirth into animal existences.
This misconception is founded on the function of the Pali term for animal, "tiracchāna." It literally means "animal," but when used in compound words, it can become figurative, meaning something like "lowly," "base," or "ignoble." In English, this would function much like the term "beastly." It is in this sense that we see terms such as "tiracchāna-kathā" (ignoble speech), or "tiracchāna-vijjā" (lowly arts - referring negatively to practices such as divination).2 Since the suttas discuss animal rebirth using a compound word - "tiracchāna-yoni," or "animal womb" - these skeptics argue that we should interpret this not as a literal rebirth as an animal, but as a figuratively "beastly" rebirth, a "lowly" or "base" existence. In his translation of the Dīgha Nikāya, Maurice Walshe stops just short of making this claim, yet betrays a sympathy for the position, stating that "it is just as possible that as a ‘destination’ for humans tiracchāna-yoni can be taken as a low rebirth." He points to DN 24 as evidence; I will address this below. He again voices sympathy for this position in his footnotes for DN 12, where he states it is "doubtful" that the term originally referred to literal rebirth as an animal, and instead "'a painful or beast-like rebirth’ might express the meaning better."3
This position is, in my opinion, absurd to the point of comedy. It should suffice to point out how nonsensical it is to accept the possibility of rebirth, yet arbitrarily draw the line at rebirth as an animal. Still, it seems neglectful to avoid further addressing this claim, so let's begin with DN 24, which Walshe pointed to as evidence that "animal womb" means "painful or beast-like rebirth."
DN 24, the Pāthika Sutta, is about a monk named Sunakkhatta who left the Buddha's order after becoming infatuated with a series of rival teachers, including Pāthikaputta, who gives the sutta its title. Its contents are largely unrelated to the subject at hand; the relevant portion is a relatively small section concerning a man who was a "kukkuravatika," a type of ascetic from the Buddha's time. These kukkuravatikas took the "dog vow," a religious practice involving behaving like a dog at all times; they ate food off of the ground, never using their hands, and they walked on all fours. They did this believing it would spiritually purify them and guarantee rebirth in a heavenly afterlife. The Buddha revealed that this man would, instead, be reborn among the lowest rank of asuras - asuras being one of the "lowly" rebirths in Buddhist cosmology, consumed by wrath and warfare.
I suppose Walshe points to this example to draw a connection between the ascetic who behaves like a dog (kukkura) and his subsequent lowly rebirth as an asura. However, it should be noted that the term "tiracchāna" does not appear at all in this sutta - neither literally nor figuratively. It seems like a stretch to reference this sutta as shedding any light whatsoever on the term "tiracchāna-yoni." The weakness of this argument is further revealed when we look at another sutta that concerns a kukkuravatika: MN 57.
MN 57, the Kukkuravatika Sutta, is much more focused on the type of dog-vow ascetic only briefly discussed in DN 24. This text tells us that the Buddha was once approached by a different kukkuravatika, as well as a similar type of ascetic: a govatika, who had vowed instead to behave like a cow. The cow-vow ascetic, named Punna, asked the Buddha about what sort of rebirth would be achieved by the dog-vow ascetic, named Seniya, who had curled up beside the Buddha like a sleepy little puppy. Despite initial reluctance, the Buddha eventually relented and revealed that if Seniya perfectly practiced the dog-vow, he would be "reborn in the company of dogs" (kukkurānam sahabyatam upapajjati). However, if he possessed the wrong view that this asceticism would deliver him to the heavens after death, he would instead be reborn in one of two destinations: hell (niraya) or "the animal womb" (tiracchāna-yoni). The Buddha made a similar statement about Punna when asked about his fate; if he practiced the cow-vow fully, he would be reborn "in the company of cows" (gunnam sahabyatam upapajjati), with the same exception being made for the previously-mentioned wrong view. Elsewhere in the suttas, we see this same terminology used to discuss rebirth "in the company" of various classes of being, and this is always in one of two senses: attaining rebirth as one of those beings, or attaining rebirth as a lesser sort of being under the authority of a higher being. We can look to MN 120 for examples of both: in the former sense, we see being reborn "in the company of the Joyful Gods" as meaning rebirth as one of those gods. In the latter sense, we see references to being reborn "in the company of the Brahmā [who oversees] 100,000 [worlds]," here meaning an existence not as that Brahmā, but as one of the deities who exist in his retinue. In MN 57, the meaning of "rebirth in the company of dogs/cows" is clearly meant in the first sense.
In other words, MN 57 straightforwardly establishes the reality of rebirth as an animal. DN 24's depiction of the dog-vow ascetic being destined for rebirth as a lowly asura in no way suggests that the term "tiracchāna-yoni" - which does not appear anywhere in DN 24 - is a figurative way to discuss a lowly, but non-animal, rebirth.
In fact, many suttas demonstrate that the destination of the "animal womb" refers to literal rebirth as an animal. For example, MN 129 lists many specific animals and what sorts of behaviors produce the kamma that leads to rebirth as those animals. In SN 15.13, the Buddha illustrated the mind-bogglingly vast span of time we have spent in samsāra by declaring that the amount of blood we've shed in past lives as cows, buffalos, rams, goats, deer, chickens, and pigs is more vast than the amount of water in the four oceans. In the Pañcagatipeyyālavagga (Chapter of Abbreviated Texts on Five Destinations) of the Samyutta Nikāya, we see references to beings attaining rebirth as animals, as well as references to animals dying and being reborn. AN 10.177 points to elephants, horses, cattle, and dogs as relatively fortunate manifestations of animal rebirth. AN 10.216 discusses rebirth as snakes, scorpions, centipedes, mongooses, cats, mice, and owls.
Let me conclude with this brief statement: there is no evidence that "animal womb" should be interpreted as a figure of speech for "lowly birth." Looking at the suttas, time and time again we find clear examples of rebirth into animal existences being discussed plainly as a matter-of-fact.
In Buddhism, the "realms" or "destinations" of rebirth are organized in a hiearchy, from lowest to highest. This hierarchy can be spatial, from the underworld up to the immaterial realms, but it can also be conceptual; for example, humans and animals share a spatial location, but human existence and animal existence are distinguished as different "realms." Within this conceptual framework, animal existence is the second lowest realm of rebirth, better than hell but worse than existence as a ghost (peta) (MN 97).
This may seem strange; what makes rebirth as an animal worse than haunting the earth as a forlorn spirit? The details of existence as a ghost will be covered elsewhere; here, let it suffice to point to MN 12. This text declares that those born in hell experience "exclusively painful feelings, sharp and severe." Animals likewise experience "sharp and severe" pain, however, not exclusively; animals are capable of enjoying pleasurable feelings. Ghosts, on the other hand, experience "mostly painful feelings," with the "sharp and severe" qualification having been dropped. This description seems to be an inverse of the one given to human existence, where we are said to experience "mostly pleasant feelings." This quality of being an inversion of human existence is also pointed out by Punnadhammo Mahathero, where he cites a commentarial text (Petavatthu-atthakātha 4:5) in which a ghost laments that he has become "a fragment of himself" (chinnathāmo). He also points out that MN 12, which uses similies to describe the various kinds of rebirth existence, uses the imagery of a tree for humans and ghosts; human existence is described like resting beneath a shady tree with lush grass underfoot, while ghostly existence is described like resting beneath a tree that offers little shade and has rugged ground underfoot.4
Furthermore, in AN 10.177, we see that ghosts are able to receive aid from offerings made in memorial rites; those born in hell or as animals are incapable of benefiting from such offerings. For these reasons, the "animal womb" is the second lowest station of rebirth in Buddhist cosmology.
It should be noted, however, that this framework is a generalized, theoretical one; there is a great degree of nuance in the details of existence within any station of rebirth. This is especially the case for animal existence, which the Buddha said was the most diverse of the "destinations" (gati) of rebirth (SN 22.100). Buddhist cosmology puts forward that beings may be born through one of four modes of conception: birth from an egg; birth from a womb; birth in moisture; or spontaenous birth, in which beings are born asexually, instantly and fully-formed (DN 33). Most beings within the cosmological hierarchy are bound to one mode of birth or another; animal existence, however, spans all four modes, even the last one, which usually applies to gods, ghosts, and hell-beings - more on this below.
So, while we may describe life as an animal broadly as being "shaply and severely painful," there are some kinds of animals that clearly enjoy a higher degree of pleasure than others. AN 10.177 points specifically to elephants, horses, cattle, and dogs as examples of creatures that enjoy the benefits of living among humans and being attended to by caretakers, having food, drink, garlands, and adornments given to them. MN 129 divides animals into several groups: those that feed on grass; those that feed on dung; those who exist in darkness; those who exist in water; and those who exist in filth. Clearly, some animals are "higher" in the hierarchy than others, and one could argue that a well-cared-for dog enjoys a "higher" existence than an especially unfortunate ghost (although I'm not aware of any such acknowledgment in the suttas).
Two types of animals stand out in the suttas as being especially prestigious, even when compared to the exceptional cases pointed out above: the nāga, and the supanna. Both of these animals belong to pan-Indian mythology, but as with many pan-Indian ideas, they developed a unique identity within Buddhism.
Sometimes the term "nāga" simply refers to ordinary snakes, particularly cobras, though this is mostly a poetic usage found in verse.5 In prose, the term more often refers to intelligent, magical serpentfolk. They are described as shapeshifters of varying moral character; some are hostile, while others are friendly, and some even long to live holy lives.
Various details about nāgas are found piecemeal throughout the early texts. They're closely associated with bodies of water; AN 8.19 explicitly identifies them as "dwellers of the ocean," alongside other mythological beings and massive sea creatures. SN 45.151 claims that they grow in the Himavā, the Himalayan mountains. Once they become strong enough, they dive into pools of water in those mountains, and travel through lakes, streams, and rivers, until they finally reach the ocean, where they fully mature. Later texts would elaborate on this idea. The commentary to AN 8.19 puts forward that nāgas live in magical palaces (vimāna) that sit on the crests of waves.6 Others present the abodes of nāgas (nāgabhavanā) as magical lands, not necessarily aquatic in nature, but accessed through bodies of water which seem to function like portals. Still others depict individuals entering nāga lands by diving into the earth or creating magical pathways.7
Above, I mentioned the four modes of birth, and how different animals may be born in any one of those four modes. Nāgas are especially diverse in that nāgas are capable of all of four modes of birth, leading to an internal hierarchy among them: those born from eggs are the lowest, while those born from wombs are second-lowest, those born in moisture are the penultimate, and those born spontaneously are the highest class of nāgas (SN 29.2).
Nāgas were said to have been present throughout the Buddha's life. Shortly after his enlightenment, the Buddha had been meditating at the root of a tree for seven days, when a mighty storm appeared. A nāgarājā - serpent king - named Mucalinda coiled his body around the Buddha's body and spread his cobra-esque hood over the Buddha's head like an umbrella, aspiring to provide the Buddha with safety and comfort. When the Buddha emerged from his meditation, and Mucalinda knew the storm had passed, he withdrew and shapeshifted into a young Brahmin. In this form, he approached the Buddha with joined palms in veneration. The Buddha wasn't fooled by Mucalinda's disguise, but all the same was moved to speak a poetic verse (Udāna 2.1). The image of Mucalinda sheltering the Buddha from the storm is a popular image throughout the Buddhist world. In paintings and statues, he is often depicted as having seven heads.
The Nāgas of the Fire-Huts
The first mass-ordination of a large number of monks involved nāgas. The Buddha had been traveling around, and eventually stopped at the town of Uruvelā. At the time, three brothers - Uruvelakassapa (Kassapa of Uruvelā), Nadīkassapa (Kassapa of the River), and Gayākassapa (perhaps named after a hill called Gayāsīsa, or a bathing pond called Gaya) - were staying in this town. These three were jatilas - "matted-hair" or "coiled-hair" ascetics - each with a considerable number of devotees. The Buddha paid a visit to the hermitage (ashram) of Uruvelakassapa and asked for his permission to stay the night in his "fire-hut" (agyāgāra). The ascetic explained that he would not personally mind accomodating the Buddha, but explained that a ferocious nāga-king was in there. The Buddha was undeterred, and after insisting that this serpent would not trouble him, the ascetic agreed to let him stay. He entered the building to meditate. The nāga-king, presumably incensed by the Buddha's audacity, flared up and began spewing fire and smoke. The Buddha, without harming any part of the nāga, summoned his own flames to swallow those of the serpent, quite literally fighting fire with fire. The two battled in this way until it looked like the fire-hut was being consumed in a blaze, alarming the jatila ascetics. However, they were stunned when, at the end of the night, the Buddha showed his begging bowl to Uruvelakassapa, wherein was contained the pacified serpent-king. "Here is your nāga, Kassapa - its fire consumed by fire." The jatilas were greatly impressed, but when the Buddha later asked to stay at another fire-hut along the Nerañjarā river, Uruvelakassapa once again protested due to the danger presented by another nāga-king. This instance played out much like the one before, only this time, at the end of the night, when the nāga-king's fires had been consumed, the Buddha's fires kept blazing. His body, completely unharmed, radiated flames of many colors. Again, he revealed the conquered serpent to Kassapa. This moved the ascetic to make meal-offerings to the Buddha, though it would take several other wondrous incidents - these not related to nāgas - to fully convince him of the Buddha's authenticty. At the end of this episode, 1,000 jatila ascetics converted and became Buddhist monks, including the three brothers (Uruvelapātihāriyakathā, from the Mahāvagga in the Vinaya - Mv.I.15.1).
An elder monk named Sāgata had a similar experience with a nāga. While the Buddha was traveling to the market town of Bhaddavatikā, various cowherds, shepherds, farmers, and travelers warned him to steer clear of the village of Ambatittha. The cause for alarm was another fierce nāga who had taken up residence in the fire-hut of another jatila ascetic. Venerable Sāgata passed through the village, pacified the nāga, and made his way to Bhaddavatikā to rejoin the Buddha. After staying there for a while, the Buddha left for the city of Kosambī, where he was welcomed by lay disciples, but these layfolk had heard about Sāgata's victory of the nāga in Ambatittha, and they soon dismissed themselves to go pay their respects to the now-famous monks. After bowing to him, they offered to bring him some delicacy as an offering. Hearing this, some mischevious monks - referred to throughout the vinaya as "the group of six" (chabbaggiya) - spoke up and asked for a rare liquor named Kāpotikā. The lay devotees prepared many drinks for him throughout various households. When the Sāgata went begging for food, they all invited him into their homes to pour him their share of the liquor. He drank so much that he passed out as he was walking out of the town gate. The Buddha, accompanied by a group of other monks, were also making their way out of Kosambī, and they saw poor Sāgata taking his booze nap. The Buddha had the monks pick him up, and they carried him to the monastery. When they put him on the ground, they pointed his head towards the Buddha as a sign of deference, but he drunkenly turned himself around and pointed his feet toward the Buddha. The Buddha asked the monks to consider the state of Sāgata - once a respectful elder, capable of conquering magical serpents - reduced to a neglectful layabout, powerless. Because of this occasion, the Buddha implemented the rule against the consumption of alcohol (Pācittiya, from the Suttavibhanga in the Vinaya - Vin Pac 51).8 It is interesting to note that a nāga was involved in the implementation of one of the most basic monastic rules.
Nāgas Who Aspire for Higher Birth
Some nāgas are ashamed of their existence as an animal. After the Buddha had established the monastic order, one such nāga devised a plan to swiftly free himself from his life as a serpent. The Buddhist monks had become renowned for their virtue, and this nāga supposed that if he could practice the holy life in their midst, he would accrue the necessary merit to achieve a human existence. Like Mucalinda before him, he shapeshifted into a young Brahmin and went to the monks to request ordination into the sangha. None the wiser, these monks accepted him as a monastic brother. The nāga shared a living quarters with another monk, and late at night, this monk got up take a walk. The shapeshifter let his guard down in this solitude and slipped into slumber, whereupon he dropped his glamour and revealed his serpent body, which unfurled throughout their quarters. His roommate returned, opened the door, and was greeted with the sight of a massive snake. He screamed, drawing the attention of other monks. They interrogated the nāga, who confessed his true identity and explained why he had deceived them. They consulted the Buddha for guidance, and he called a meeting to address the issue. "You nāgas are not capable of practicing the Dhamma like us, existing as you are - however, if you observe uposatha9 , you can be freed from this existence and swiftly achieve a human birth." Despite this good news, the nāga broke out in tears, cried out, and left (Tiracchānagatavatthu, from the Mahāvagga in the Vinaya - Mv.I.63.1). Because of this incident specifically, some monks later had Upāli question a young Brahmin who came to ask for ordination (Mātughātakavatthu, also from the Mahāvagga - Mv.I.64.1). It became standard practice to ask anyone seeking ordination to confirm that they were indeed human - a policy which endures to this day. In SN 29.3-6, we agan see mention of nāgas observing uposatha in order to achieve a higher rebirth, though here they seem to be aspiring for a heavenly realm and not a human existence.
Nāgas and Protection Prayers
Once, a monk in Sāvatthī died after being bitten by a snake. In response, the Buddha told the monks staying there that this happened because of that monk's failure to cultivate metta (loving-kindness) for "the four royal snake clans" (cattāri ahirājakulā). These four are named as the Virūpakkhas, the Erāpathas, the Chabyāputtas, and Kanhāgotamakas. The Buddha then gives a paritta (a protective prayer) for the monks to recite which declares loving-kindness towards those four clans, as well as all other creatures, wishing for them to "only see nice things" and be free from harm, and in turn, refrain from themselves harming those who recite the paritta (AN 4.67). This sutta does not use the term "nāga," instead using the more basic term "ahi" (snake) to refer to the four clans, but the fact that they are called "royal" (rāja) implies that we are not dealing with ordinary snakes, and this implication is strengthened by the appearance of "Virūpakkha" as the name of a god who is called "the lord of nāgas" (nāgānañca adhipati) in DN 32.
That sutta, DN 32, tells the story of a time when the Buddha was visited by the gods known as "The Four Great Kings" (cattāro mahārājā), accompanied by a great number of other supernatural beings, including nāgas. One of those Great Kings, Vessavana, told the Buddha that many spirits (yakkhā) have no respect for the Buddha or his monks, and since many disciples go out in the wilderness where such spirits dwell, he wished to teach the Buddha a prayer called "the Ātānātiya Protection" (ātānātiya rakkha), which he could then teach to his followers, monastic and lay alike. What follows is a long formula praising past Buddhas, Gautama himself, and a host of various supernatural lords and their followers. In this formula, Virūpakkha is revealed to be one of those Four Great Kings, honored by nāgas, ward of the Western Quadrant. Perhaps the "Virūpakkha" clan of royal snakes are the nāgas who revere this god.
Nāgas at the Great Assembly in the Woods
DN 20 tells of another time a great number of supernatural beings visited the Buddha, nāgas among them, and here we find more details about the magical serpents. At the time, the Buddha was staying in his home country, in a great forest with a large company of 500 enlightened monks. Most of the gods from a group of ten world-systems appeared to see the Buddha and his disciples there in the woods. Four gods from "the Pure Abodes" (suddhāvāsa) saw this and decided to manifest there themselves in order to recite a verse for the Buddha. In these verses, they celebrated "the great congregation in the woods," and the achievements of those who had gathered there. The Buddha declares to the monks that these great gods had joined them, and began speaking in verse himself, teaching the monks there about the various types of being who had come to see the great assembly. As he taught them, the monks became able to see these beings, depending on their own affinity to such supernatural vision; some monks were only able to see 100 such beings, while others saw "an endless number spread out in every direction."
Among these beings were various groups of nāgas. There were the nāgas of "Nābhasa Lake," and those from Vesālī and Takkasilā (the famous Taxila in modern Western Pakistan). Two groups of nāgas called the Kambalas and the Assataras are also named, and Sujato notes that these are frequently mentioned together in Sanskrit texts, including the Mahābhārata. Nāgas from Payāga - a holy place where the Ganges and Yamuna rivers meet - are said to have attended "with their kin." Nāgas from Yamunā also came, as well as "the Dhatarattha nāgas." Sujato notes that this last group is also found in Sanskrit texts, often alongside various other deities featured in this text. Finally, an individual "great nāga" called Erāvana is named as an attendee. Sujato notes that in Buddhist texts this name variously refers to a nāgarājā (as in this text and Snp 2.14) or the magical elephant mount of the god Sakka; this confusion results from the fact that "nāga" may also mean "elephant." Furthermore, Sanskrit texts also discuss "the Erāvana nāgas" as a group alongside the Dhataratthas and the others.
The Relic-Revering Nāga-King
Finally, in DN 16 - the sutta which describes the Buddha's final days and how his disciples proceeded in the days following his death - it is said that, following his cremation, the Buddha's relics were divided into eight shares and distributed throughout the various lands where the Buddha had taught. One of these shares, seemingly a tooth relic, was venerated by a nāga-king in Rāmagāma, a village along the Ganges river in the Koliya Republic.
Supannas are winged bird-like creatures, sometimes translated as "phoenixes" to convey their generally supernatural character, but one shouldn't otherwise associate the specific qualities of European phoenixes with Indian supannas. They are also called garulas, which in Sanskrit is "garuda," a name by which they are more commonly known. Compared to nāgas, supannas are relatively vague figures in the early texts, although they became more prominent in later traditions, especially tantric forms of Buddhism.
Supannas are associated with the kūṭasimbalī (red silk-cotton) tree (SN 48.70). Like the nāgas, they are capable of all four modes of birth, and are similarly ranked in an internal hierarchy among themselves (SN 30.2). Interestingly, this hierarchy is defined explicitly relative to the ranks of nāgas, who serve as their prey. Supannas born from eggs are only capable of "carrying off" nāgas likewise born from eggs, while supannas born from a womb can prey on both womb-born and egg-born nāgas, and so on, up to spontaneously-born supannas, who can feed on any sort of nāga. The enmity between these magical birds and serpents would become a prominent theme in later stories.
Supannas at the Great Assembly in the Woods
Above, we looked at the DN 20's discussion of the nāgas that attended the Great Assembly in the woods. Supannas were also in attendance, and the Buddha likewise described them to his monks. Front-and-center is their role as the predators of nāgas, as the Buddha introduced them as "those who forcefully seize the nāga-kings." They were also described as "divine, twice-born birds with piercing vision." Sujato notes that birds in general are described as "twice-born" in the texts, since they hatch from eggs (the second birth) laid by a mother (the first birth). The Buddha said that they had "swooped down to the wood from the sky."
The sutta tells us that the nāga-kings there were unafraid, knowing they were being protected by the Buddha, who "introduced the nāgas and the supannas with gentle words," and both groups of beings are described as having taken refuge in the Buddha there in the forest. Otherwise, the sutta offers no details on the supannas who came to the assembly, reflecting the general tendency of the early texts to favor the nāgas.
Throughout the suttas, many different qualities or behaviors are pointed out as causes for rebirth as an animal. Before giving examples, I would like to repeat a point I made in my essay about rebirth: kamma does not work in a simple linear fashion. Any type of kamma we have performed throughout our innumerable lifetimes will produce the appropriate effects whenever the conditions are right for its ripening. This means that people who have spent this lifetime performing the sorts of kamma identified as the cause for animal rebirth may not experience the results of that kamma in the lifetime which will follow after their death here; some other sort of kamma may come to fruition instead.
The most basic cause for animal rebirth (as well as rebirth in hell) is the possession of Wrong View (micchāditthi), pointed out in many suttas (ex: MN 57). The stock description for "Wrong View" in the suttas is: believing there is no benefit in giving or making offerings; believing that kamma does not produce results; not believing in rebirth; believing one has no obligation to their parents; not believing that some beings are born spontaneously (in other words: not believing in beings such as gods, ghosts, or hell-beings); believing that no one has achieved knowledge of the other realms of existence through personal insight (ex: AN 10.176).
Other suttas point to more specific misunderstandings as Wrong Views, and these usually pertain to mistaken beliefs about how one can be reborn in a heavenly afterlife. For example, as we saw in MN 57, dog-vow and the cow-vow ascetics might hold the wrong view that their bizarre behavior will lead to rebirth in a godly world, and this will result in rebirth in hell or "the animal womb." In SN 42.2, a theatrical dancer told the Buddha that he had been taught that entertainers like himself would be reborn among "the laughing gods." In SN 42.3, a warrior told the Buddha that he had been taught that warriors who die in battle will be reborn among "the gods of the fallen." Both of these are dismissed as Wrong Views which will lead to rebirth in hell or as an animal.
AN 10.176 identifies "the ten paths of bad kamma," a standard list of unrighteous actions found throughout the suttas, as the reason "hell, the animal womb, the world of ghosts, or any other unfortunate state (duggati) may be found." To elaborate here would be excessive; if you want more information, I must once again direct you to my essay about rebirth. I have already mentioned MN 129, which lists several different groups of animals. Again, these are: those that feed on grass; those that feed on dung; those who exist in darkness; those who exist in water; and those who exist in filth. The cause for rebirth in each instance is attributed to "having been a glutton in this world" (bālo idha pubbe rasādo) and "having performed evil kamma in this world" (idha pāpāni kammāni karitvā)."
AN 10.216 is a brief discourse which emphatically makes the point that the kamma we perform will come back to us and determine our rebirth. The sutta draws a parallel between one who is "creepy" (samsappati) in body, speech, and mind, and "creepy animals" (saṁsappajātikā tiracchānayoni). One who is "creepy in body, speech, and mind" is defined using the standard list of the "ten paths of bad kamma," though it is not referred to as such. Such kamma is said to lead to hell, or existence as a "creepy animal," defined as "animals that creep away after seeing humans" (tiracchānayonikā sattā manusse disvā samsappanti). Specific examples listed include snakes, scorpions, centipedes, mongooses, cats, mice, and owls.
AN 8.40 presents the violation of the basic ethical precepts - killing, stealing, sexual misconduct, lying, and drinking alcohol - as potential causes for animal rebirth. In addition, other forms of "Wrong Speech" are also included alongside lying: divisive speech, harsh speech, and idle chatter. In AN 2.26, monks specifically are warned against hiding their misdeeds - presumably, this means failing to confess relevant wrongdoings during regular communal confessions - as this, too, can lead to rebirth as an animal.
Recalling the diversity of possibilities within animal existence, AN 10.177 indicates that some of the more fortunate outcomes - birth as a well-attended elephant, horse, cattle, or dog - may await a person who has performed the ten paths of bad kamma, but has also given offerings of food, drink, clothing, carriages, garlands, perfumes, cosmetics, beds, housing, and sources of light.
Finally, I want to discuss the idea of "aspirational rebirth" (sankhārupapatti) as it pertains to animal existence. Throughout the suttas, we find references to "aspriational rebirth," which results from someone cultivating the intention to reborn in a certain state of existence while performing the appropriate sorts of kamma in the meantime. MN 120 - the Sankhārupapatti Sutta - is an entire discourse devoted to this concept. Generally, this applies to rebirth as a well-to-do, fortunate human being, or any of the various classes of gods in the higher stations of rebirth. However, we sometimes see allusions to the possibility of aspirational rebirth as an animal, which is interesting, given that animal existence is considered so lowly in Buddhist cosmology. There is the example of the dog-vow and cow-vow ascetics, seen in MN 57, who could have been reborn as those animals after having perfected their respective ascetic practices - though, if they possessed the wrong view that their asceticism would lead to heaven, that kamma could have just as easily seen them reborn in hell!
In some suttas regarding nāgas and supannas, we see that rebirth as those mythical creatures results from having performed both good and bad kamma, while also having cultivated the intention to be reborn as either a nāga (SN 29.7-10) or a supanna (SN 30.3-6). In either case, it is the act of giving specifically that is said to be the "good kamma" at play, with the offerings given being the same as those found in AN 10.177 (SN 29.11-20 & SN 30.7-16).
 Many of the textual examples I will examine in this essay were pointed out by Punnadhammo Mahathero in his book "The Buddhist Cosmos." In fact, the entire series of essays on cosmology I am publishing to my website rests heavily on this one book, with the present essay in particular being almost entirely built off of his work. I want to use this first footnote here to acknowledge how much I have relied on this incredible book to present the information here. If you're interested in further reading, particularly if you want to see material from the commentarial sources, you should absolutely check it out.
 These come from Jātaka stories - 543 & 506 - cited by Punnadhammo
 This example was also pointed out by Punnadhammo, with additional details taken from SuttaCentral dictionary definitions for the various terms found in the story
 Uposatha is a ritual day of observance practiced by monastics as well as devout lay followers. For more information, see the first footnote in my analysis of DN 2.
 Punnadhammo (Mahāthero) : The Buddhist Cosmos: A Comprehensive Survey of the Early Buddhist Worldview according to the Theravada and Sarvastivada sources (Book)
 Walshe, Maurice : The Long Discourses of the Buddha: A Translation of the Dīgha Nikāya (Book)