Śatapatha Brāhmaṇa ("of a hundred paths") 4.5.2.13

4.5.2.13

tadāhuḥ | kvaitaṃ garbhaṃ kuryāditi vṛkṣa evainamuddadhyurantarikṣāyatanā vai garbhā antarikṣamivaitadyadvṛkṣastadenaṃ sva evāyatane pratiṣṭhāpayati tadu vā āhurya enaṃ tatrānuvyāharedvṛkṣa enam mṛtamuddhāsyantīti tathā haiva syāt

Here now they say, 'What is he to do with that embryo?' They may expose it on a tree; for embryos have the air for their support, and the tree is, as it were, the same as the air: thus he establishes it on its own support. But, say they, if, in that case, any one were to curse him, saying, 'They shall expose him dead on a tree,' then verily it would be so.