The bible tells us.
Genesis 1:
25 And God made the beast of the earth after his kind, and cattle after their kind, and every thing that creepeth upon the earth after his kind: and God saw that it was good.
26 And God said, Let us make man in our image, after our likeness: and let them have dominion over the fish of the sea, and over the fowl of the air, and over the cattle, and over all the earth, and over every creeping thing that creepeth upon the earth.
27 So God created man in his own image, in the image of God created he him; male and female created he them.
28 And God blessed them, and God said unto them, Be fruitful, and multiply, and replenish the earth, and subdue it: and have dominion over the fish of the sea, and over the fowl of the air, and over every living thing that moveth upon the earth.
Genesis 2:
6 But there went up a mist from the earth, and watered the whole face of the ground.
7 And the Lord God formed man of the dust of the ground, and breathed into his nostrils the breath of life; and man became a living soul.
8 And the Lord God planted a garden eastward in Eden; and there he put the man whom he had formed.
18 And the Lord God said, It is not good that the man should be alone; I will make him an help meet for him.
21 And the Lord God caused a deep sleep to fall upon Adam, and he slept: and he took one of his ribs, and closed up the flesh instead thereof;
22 And the rib, which the Lord God had taken from man, made he a woman, and brought her unto the man.
23 And Adam said, This is now bone of my bones, and flesh of my flesh: she shall be called Woman, because she was taken out of Man.
But it never tells us
why he created humans, at least as far as I can tell. So, why us? Why not leave the place just as it was pre A&E?