The frog, which appears in teeming multitudes with the rising of the waters and transforms from a limbless tadpole into a four-legged adult, was across the ancient world an emblem of fertility, birth and renewal. In Egypt it was embodied in Heqet, the frog-headed goddess of childbirth and midwifery, who gave the breath of life to the newborn, and the frog hieroglyph could stand for a great number, for teeming abundance. The Book of Exodus turns the same fertility against Egypt in the second plague, when frogs swarm out of the Nile to fill the land, houses and beds, the fertile creature become a torment.
The frog's ancient status as an emblem of abundant, teeming life has been undercut by a real and severe modern crisis: since the late twentieth century a fungal pathogen, Batrachochytrium dendrobatidis, chytrid fungus, has spread across the world's amphibian populations, driving numerous frog species to extinction or near-extinction and prompting quarantine, captive-breeding and biosecurity regulations in many countries; herpetologists now count the chytrid pandemic among the worst wildlife disease events ever documented, a stark modern counterpoint to the frog's old symbolism of fertility and plenty.