Rarity of Humanoids

Rarity of Humanoids

Human beings (manussa loka)

Rebirth as a human being is extraordinarily rare.

The assumption here is there are only 5 types of humanoids in only five planets.

Below is a reproduction of various types of beings in the universe or galaxies

The Thirty-one Planes of Existence

Scattered throughout the suttas are references to as many as thirty-one distinct "planes" or "realms" of existence into which beings can be reborn during their long wandering through samsara. These range from the extraordinarily grim and painful hell realms all the way up to the most exquisitely refined and blissful heaven realms. Existence in every realm is temporary; in Buddhist cosmology there is no eternal heaven or hell. Beings are born into a particular realm according to their past kamma. When they pass away, they take rebirth once again elsewhere according to the quality of their kamma: wholesome actions bring about a favorable rebirth, while unwholesome actions lead to an unfavorable one.
The realms of existence are customarily divided into three distinct "worlds" (loka), listed here in descending order of refinement:
 
The realms of existence are customarily divided into three distinct "worlds" (loka), listed here in descending order of refinement:

1. The Immaterial World (arupa-loka).
Consists of four realms that are accessible to those who pass away while meditating in the formless jhanas. 


2. The Fine-Material World (rupa-loka).
Consists of sixteen realms whose inhabitants (the devas) experience extremely refined degrees of mental pleasure. These realms are accessible to those who have attained at least some level of jhana and who have thereby managed to (temporarily) suppress hatred and ill will. They are said to possess extremely refined bodies of pure light. The highest of these realms, the Pure Abodes, are accessible only to those who have attained to "non-returning," the third stage of Awakening. The Fine-Material World and the Immaterial World together constitute the "heavens" (sagga).

3. The Sensuous World (kama-loka).
Consists of eleven realms in which experience — both pleasurable and not — is dominated by the five senses. Seven of these realms are favorable destinations, and include our own human realm as well as several realms occupied by devas.
The lowest realms are the four "bad" destinations, which include the animal and hell realms.

I. The Immaterial World (arupa-loka)

Realm Comments Cause of rebirth here
(31) Neither-perception-nor-non-perception (nevasaññanasaññayatanupaga deva)
(30) Nothingness (akiñcaññayatanupaga deva)
(29) Infinite Consciousness (viññanañcayatanupaga deva)
(28) Infinite Space (akasanañcayatanupaga deva)
The inhabitants of these realms are possessed entirely of mind.
Having no physical body, they are unable to hear Dhamma teachings.

II. The Fine-Material World (rupa-loka)

(27) Peerless devas (akanittha deva) These are the five Pure Abodes (suddhavasa), which are accessible only to non-returners (anagami) and arahants. Beings who become non-returners in other planes are reborn here, where they attain arahantship.

Among its inhabitants is Brahma Sahampati, who begs the Buddha to teach Dhamma to the world (

(26) Clear-sighted devas (sudassi deva)
(25) Beautiful devas (sudassa deva)
(24) Untroubled devas (atappa deva)
(23) Devas not Falling Away (aviha deva)
(22) Unconscious beings (asaññasatta)
Only body is present; no mind.
(21) Very Fruitful devas (vehapphala deva)
Beings in these planes enjoy varying degrees of jhanic bliss.
(20) Devas of Refulgent Glory (subhakinna deva)
(19) Devas of Unbounded Glory (appamanasubha deva)
(18) Devas of Limited Glory (parittasubha deva)
(17) Devas of Streaming Radiance (abhassara deva)
(16) Devas of Unbounded Radiance (appamanabha deva)
(15) Devas of Limited Radiance (parittabha deva)
(14) Great Brahmas (Maha brahma)
One of this realm's most famous inhabitants is the Great Brahma, a deity whose delusion leads him to regard himself as the all-powerful, all-seeing creator of the universe
(13) Ministers of Brahma (brahma-purohita deva)
Beings in these planes enjoy varying degrees of jhanic bliss.
(12) Retinue of Brahma (brahma-parisajja deva)


III. The Sensuous World (kama-loka)

Happy Destinations (sugati)

(11) Devas Wielding Power over the Creation of Others (paranimmita-vasavatti deva)
These devas enjoy sense pleasures created by others for them.
Mara, the personification of delusion and desire, lives here.
(10) Devas Delighting in Creation (nimmanarati deva)
These devas delight in the sense objects of their own creation.
(9) Contented devas (tusita deva)
A realm of pure delight and gaiety.
Bodhisattas abide here prior to their final human birth.
This is where the bodhisatta Maitreya (Metteya), the next Buddha, is said to dwell.
(8) Yama devas (yama deva)
These devas live in the air, free of all difficulties.
(7) The Thirty-three Gods (tavatimsa deva)
Sakka, a devotee of the Buddha, presides over this realm.
Many devas dwelling here live in mansions in the air.
(6) Devas of the Four Great Kings (catumaharajika deva)
Home of the gandhabbas, the celestial musicians, and the yakkhas, tree spirits of varying degrees of ethical purity. The latter are analogous to the goblins, trolls, and fairies of Western fairy tales.


(5) Human beings (manussa loka)

Rebirth as a human being is extraordinarily rare.

It is also extraordinarily precious, as its unique balance of pleasure and pain facilitates the development of virtue and wisdom to the degree necessary to set one free from the entire cycle of rebirths.

The development of virtue and wisdom

The attainment of stream-entry (sotapatti) guarantees that all future rebirths will be in the human or higher realms.

States of Deprivation (apaya)

(4) Asuras (asura)
The demons — "titans" — that dwell here are engaged in relentless conflict with each other.
(3) Hungry Shades/Ghosts (peta loka)
Ghosts and unhappy spirits wander hopelessly about this realm, searching in vain for sensual fulfillment.
(2) Animals (tiracchana yoni)
This realm includes all the non-human forms of life that are visible to us under ordinary circumstances: animals, insects, fish, birds, worms, etc.
(1) Hell (niraya)
These are realms of unimaginable suffering and anguish.
Should not be confused with the eternal hell found in other religious traditions, since one's time here is — as it is in every realm — temporary.

Heaven

In Buddhist cosmology, the heaven realms are blissful abodes whose present inhabitants (the devas) gained rebirth there through the power of their past meritorious actions. Like all beings still caught in samsara, however, these deities eventually succumb to aging, illness, and death, and must eventually take rebirth in other realms — pleasant or otherwise — according to the quality and strength of their past kamma. The devas are not always especially knowledgeable or spiritually mature — in fact many are quite intoxicated by their sensual indulgences — and none are considered worthy of veneration or worship.
Nevertheless, the devas and their happy realms stand as important reminders to us both of the happy benefits that ensue from the performance of skillful and meritorious deeds and, finally, of the ultimate shortcomings of sensuality.