SB 3.29.30

rūpa-bheda-vidas tatra
 tataś cobhayato-dataḥ
teṣāṁ bahu-padāḥ śreṣṭhāś
 catuṣ-pādas tato dvi-pāt
Synonyms: 
rūpa-bheda — distinctions of form; vidaḥ — those who perceive; tatra — than them; tataḥ — than them; ca — and; ubhayataḥ — in both jaws; dataḥ — those with teeth; teṣām — of them; bahu-padāḥ — those who have many legs; śreṣṭhāḥ — better; catuḥ-pādaḥ — four-legged; tataḥ — than them; dvi-pāt — two-legged.
Translation: 
Better than those living entities who can perceive sound are those who can distinguish between one form and another. Better than them are those who have developed upper and lower sets of teeth, and better still are those who have many legs. Better than them are the quadrupeds, and better still are the human beings.
Purport: 

It is said that certain birds, such as crows, can distinguish one form from another. Living entities that have many legs, like the wasp, are better than plants and grasses, which have no legs. Four-legged animals are better than many-legged living entities, and better than the animals is the human being, who has only two legs.