The Seven forms of Life
A person can take birth as any of the seven life forms: Devas, humans, terrestrial animals, aerial life forms, crawling creatures, aquatic beings and plants.
In Srimad Bhagavatam, we see that it was Lord Krishna who gave liberation to all these life forms:
• Vatsasura, the bull (terrestrial animal)
• Bakasura, the stork (aerial life form)
• Sankachuda and Aghasura the pythons (crawling creatures)
• Kaliya the venomous water serpent (aquatic being)
• Nalakupura and Manigreeva — The two ‘Marudha’ trees (plant forms)
• The innumerable gopas and gopis who were in human form
• Indra, Varuna and other devas who were tamed by the Lord.