SB 7.14.36

jīva-rāśibhir ākīrṇa
 aṇḍa-kośāṅghripo mahān
tan-mūlatvād acyutejyā
 sarva-jīvātma-tarpaṇam
Synonyms: 
jīva-rāśibhiḥ — by millions and millions of living entities; ākīrṇaḥ — filled up or spread over; aṇḍa-kośa — the whole universe; aṅghripaḥ — like a tree; mahān — very, very great; tat-mūlatvāt — because of being the root of this tree; acyuta-ijyā — worship of the Supreme Personality of Godhead; sarva — of all; jīva-ātma — living entities; tarpaṇam — satisfaction.
Translation: 
The entire universe, which is full of living entities, is like a tree whose root is the Supreme Personality of Godhead, Acyuta [Kṛṣṇa]. Therefore simply by worshiping Lord Kṛṣṇa one can worship all living entities.
Purport: 

In Bhagavad-gītā (10.8) the Lord says:

ahaṁ sarvasya prabhavo
 mattaḥ sarvaṁ pravartate
iti matvā bhajante māṁ
 budhā bhāva-samanvitāḥ

“I am the source of all spiritual and material worlds. Everything emanates from Me. The wise who perfectly know this engage in My devotional service and worship Me with all their hearts.” People are very much anxious to give service to other living entities, especially to the poor, but although they have manufactured many ways to give such help, actually they are expert in killing the poor living entities. This sort of service or mercy is not recommended in the Vedic wisdom. As stated in a previous verse, it has been decided (niruktam) by expert saintly persons that Kṛṣṇa is the root of everything and that worshiping Kṛṣṇa is worshiping everyone, just as supplying water to the root of a tree means satisfying all of its branches and twigs.

Another point is that this universe is full of living entities from top to bottom, on every planet (jīva-rāśibhir ākīrṇaḥ). Modern scientists and so-called scholars think that there are no living entities on planets other than this one. Recently they have said that they have gone to the moon but did not find any living entities there. But Śrīmad-Bhāgavatam and the other Vedic literatures do not agree with this foolish conception. There are living entities everywhere, not only one or two but jīva-rāśibhiḥ — many millions of living entities. Even on the sun there are living entities, although it is a fiery planet. The chief living entity on the sun is called Vivasvān (imaṁ vivasvate yogaṁ proktavān aham avyayam). All the different planets are filled with different types of living entities according to different living conditions. To suggest that only this planet is filled with living entities and that others are vacant is foolish. This betrays a lack of real knowledge.