Srila Prabhupada often referred to the Puranic statement that there are 8.4 million species. A couple of years ago, scientists publicized their latest estimate of the number of species on earth: 8.7 million. But don’t get too excited about the closeness of these two numbers.

First of all, scientists estimate that at least 90% of the species that ever existed are extinct, meaning that something like 87 million species have lived at one time or another. The scientists’ count would vary with the progression of the ages. But the Vedic count would not. The Srimad-Bhagavatam relates how all the species of life appeared at or near the beginning of the creation. And even though we don’t find each of the 8.4 million species on earth today, that doesn’t mean any of them are extinct. The Vedic literature rejects the parochial view that life exists only on earth and is carbon-based. The Bhagavad-gita reveals that life is a transcendental phenomenon having nothing to do with mixtures of material elements. Life is the soul, or atma, and can exist anywhere in the universe.

Often overlooked in attempts to reconcile the scientists’ count of species with Prabhupada’s is that the same word is being used for two different things. Consider that the Vishnu Purana verse Prabhupada would quote about the 8.4 million species mentions 400,000 species of humans. Science recognizes only one surviving human species homo sapiens and only two extinct ones. While it is true that according to Vedic literature human species exist throughout the universe, Prabhupada indicated that various human species exist on this planet as well.

Though the Vedic and modern systems for categorizing species differ, it is still significant that the Vedas give an exact number, whereas scientists cannot. We should also keep in mind that the modern system is somewhat arbitrary. It’s a contrivance a convenient tool, but not without its glitches.

What is a species according to the Vedic literature? The Vishnu Purana verse Prabhupada would quote doesn’t contain any word that could be translated as “species.” It’s a list: “9,00,000 aquatics, 2,000,000 non moving entities,” and so on. Besides “species,” Srila Prabhupada also referred to them in other ways, such as “bodily forms” and “forms of life.” He said they come about by the mixing of the three modes of material nature: goodness, passion, and ignorance. Krishna says in the Bhagavad-gita (13.22) that souls in human bodies, influenced by particular mixtures of the modes according to their choices, determine which species they’ll enter after death.

The number 8.4 million is not as important as the point Prabhupada often made when he cited that number: We, the soul, have been in all those nonhuman bodies and risk returning to any of them if we misuse the human form of life. Only in human life can we awaken our innate Krishna consciousness and return to our original home with Krishna in the spiritual world. We must not waste our life improving our standards of eating, sleeping, mating, and defending the sole concerns of other species.

Regarding varieties of human species, Prabhupada says that humans can be categorized as “uncivilized, half-civilized, and civilized.” A civilized human being, in the opinion of the Vedic scriptures, is someone on a progressive spiritual path. The person in the highest species of human beings, therefore, is one whose consciousness is absorbed in pursuing pure love of God, the attainment of which frees one forever from any risk of reentering lower forms of life.