arvāk-srotas tu navamaḥ
kṣattar eka-vidho nṛṇām
rajo ’dhikāḥ karma-parā
duḥkhe ca sukha-māninaḥ
The creation of the human beings, who are of one species only and who stock their eatables in the belly, is the ninth in the rotation. In the human race, the mode of passion is very prominent. Humans are always busy in the midst of miserable life, but they think themselves happy in all respects.
Reference:- SB 3.10.26