Srimad-Bhagavatam: Canto 3 - Chapter 1 - Verse 19
Sanskrit:
विससर्जात्मन: कायं नाभिनन्दंस्तमोमयम् ।जगृहुर्यक्षरक्षांसि रात्रिं क्षुत्तृट्समुद्भवाम् ॥ १९ ॥
ITRANS:
visasarjātmanaḥ kāyaṁnābhinandaṁs tamomayamjagṛhur yakṣa-rakṣāṁsirātriṁ kṣut-tṛṭ-samudbhavām
Translation:
Out of disgust, Brahmā threw off the body of ignorance, and taking this opportunity, Yakṣas and Rākṣasas sprang for possession of the body, which continued to exist in the form of night. Night is the source of hunger and thirst.