According to ancient Vedic Sanskrit texts:

Number of species living in the water: 900,000

Number of kinds of sthāvara (non-moving living entities such as trees and plants): 2,000,000

Number of species of insects and reptiles : 1,100,000

Number of species of birds : 1,000,000

Number of varieties of quadrupeds 3,000,000

Number of human species 400,000 that exist on many planets

Number of Manus who manifest in one kalpa (one day of Brahmā ) fourteen Manus

Duration of one day of Brahmā 1,000 yugas (4.32 billion years)

Number of Manus who manifest during one month of Brahmā 420 Manus

Number of Manus who manifest during one year of Brahmā 5,040 Manus

Number of Manus who manifest during the lifetime of one Brahmā 504,000 Manus

Total duration of four yugas (Satya+Treta+Dvapara+Kali) 4,320,000 years

Number of the present Manu (Vaivasvata Manu ) 7th Manu
Age of our (Vaivasvata) Manu 27 divya-yugas [27 x 4,320,000 solar years]

Duration of 100 years of Brahma (his lifetime duration) 311,040,000,000,000 years

Duration of one manvantara , the lifespan of one Manu seventy-one yugas (=71*4,320,000 years

Duration of Satya yuga 1,728,000 years

Duration of Tretā-yuga 1,296,000 years

Duration of Dvāpara-yuga 864,000 years

Duration of Kali-yuga 432,000 years

Duration of lifetime of human in Satya yuga around 100,000 years

Duration of lifetime of human in Tretā-yuga around 10,000 years

Duration of lifetime of human in Dvāpara-yuga around 1,000 years

Duration of lifetime of human in Kali-yuga around 100 years.

And the entire life of Brahma is one breath of Garbodakasayi Visnu which over 311 trillian of our years .

Creation of the Material Universe

The Lord’s creation has two principal components. The spiritual and the material worlds. The material world comprises of millions of universes each presided by its own Brahma, each comprising of millions of planets like our planet Earth.

All this put together makes up a fourth of the total creation. The remaining three-fourths is the spiritual universe, containing billions of spiritual planets, at the center of which is Goloka the eternal abode of Sri Krishna, the Supreme Personality of Godhead.

The spiritual universe is also called Vaikuntha, which means ‘free from worry’, since resident of this planet are free from birth-death-disease-old age. They have spiritual bodies than never wear out, and they live blissfully, eternally in service of Krishna.

The material universe is like a dark cloud covering one corner of the self illuminated spiritual worlds. In this corner, Karanadakasayi Vishnu, an expansion of Sri Krishna lies in a deep mystic slumber, creating innumerable universes and destroying them as well.

When each universe is created, Karanadakasayi Vishnu expands and enters into each of them as Garbhodakasayi Vishnu and fills the lower half of the universe with the waters of the causal ocean. On this ocean, He lies down on His partial expansion, Ananta Shesha, and enters into Yoganidra or a deep mystic trance.

From the navel of Garbhodakasayi Vishnu emanates a lotus flower that covers the complete universe, and on the lotus flower is born Brahma, the first living entity of the material world.

Brahma, like any one of us, is born in the darkness of ignorance. He is completely bewildered by the darkness surrounding him and in searching for some clues tries to look in all the four directions, thereby getting four heads.

Not finding any clues around himself, he descends down the stalk of the lotus flower, but after a long time gives up and reverts to his original position on the lotus flower. Finally when all fails, Brahma, driven by the forces within himself, performs severe austerities for one hundred of his years, concentrating on the Supreme Personality of Godhead.

Krishna, pleased by the austerities of Brahma, accepts him as a disciple and initiates him with the sacred Gopala Gayatri mantra. So Lord Brahma, who was born in the nescience of darkness is now by the mercy of his spiritual master Sri Krishna, a qualified Brahman, empowered to undertake the task of creating the universe.

As a pure devotee, Lord Brahma begins by glorifying his spiritual master, Sri Krishna with beautiful prayers recorded in the Brahma Samhita, and Krishna pleased by the complete surrender of Brahma imparts to him the Vedic knowledge and empowers him to undertake the task of creating the universe.

Lord Brahma now looks at the strong winds and water surrounding him. Having matured with long penance, self realization and transcendental knowledge, he drinks the wind completely along with the water.

Engaging in the devotional service of Krishna, he enters into the whorl of the lotus spread all over the universe and divides in into three parts and then into fourteen. The three worlds are the Patalaloka, the Bhuvaraloka and the Svargaloka, with the fourteen planetary systems are divided amongst them.

Having created the gross material universe, Lord Brahma then creates the subtle elements of the material universe, which includes self-deception, the sense of death, anger after frustration, the sense of false ownership and the illusory body conception or forgetfulness of one’s real identity.

Even though Lord Brahma did this as his duty, he felt sorrow at such a sinful task and then purifies himself by meditating on Sri Krishna. Thus he began another term of creation in which he creates all the plant and animal life forms that would spread over the complete universe.

In the beginning, Lord Brahma created four great sages, Sanaka, Sanandan, Sanatana and Sanat, personifying the four principles of spiritual knowledge. Desiring to populate the universe he had created, Lord Brahma requested his four sons to have progeny.

The four Kumaras, as they are collectively called however were so attached to Sri Krishna that they were unwilling to become Grahasthas (house holders) and thus refused the request of their father. Since the four Kumaras had refused him for a much higher purpose, Lord Brahma accepted their decision, but being in the mode of passion, could not control the anger in his mind.

The manifestation of this anger was born as a child from between the eyebrows of Lord Brahma.

The child had a reddish-blue body and was crying for a name and place. Lord Brahma named him Rudra, the foremost of the living entities. On the instructions of his father, Rudra produced several sons and grandsons, who had the same fiery temperament as their father and attempted to devour the entire universe including Lord Brahma.

Seeing this Lord Brahma request Rudra to control his progenies and direct their energy to austerity and penance. Only when the time of annihilation comes, will these destructive energy be released in the service of Krishna. So this is the nature of the material world. Its destruction is imminent and fixed from the time of its creation.

Lord Brahma then created ten sons from various parts of his body. These included the great sage Narada, who was born from his mental deliberation, Pualstya Muni who begot the demoniac race which would later produce Ravana, Bhrigu Muni the greatest of the sages who started the pious Bhargava dynasty, Prajapati Daksha the great progenitor who fathered tens of thousands of sons and daughters, Marici, who fathered Kasyapa Muni and married him to the thirteen daughters of Prajapati Daksha.

These wives of Kasyapa Muni included Aditi through which the demigods like Indra were born and Diti through which many demons like Hiranyakasha and Hiranykashyapu were born.

Also born from Brahma was Sage Vashista, whose grandson was Parasara Muni, the father of Veda Vyasa, and the grandfather of Sukhadeva Goswami. In this way millions of demons and demigods were created.

Still not satisfied with the creative forces in the universe, Lord Brahma manifested an intense desire to produce more progeny. From his body came two forms, Syambhuva Manu and his queen Satarupa, who united to created millions of offspring’s that gradually filled the universe, generation after generation.

So in this way, as the universe moves under the inexorable control of Kala or time, the living entities are moving into different life forms driven by their desires and karmic reactions.

However a very few fortunate souls, by the mercy of a pure devotee, are able to understand their true position as the servitors of Sri Krishna and are able to escape this endless cycles of birth and death to return to their eternal, indestructible abode in the spiritual sky.