The Lightning Worm
The lightning worm, Amynthas adtonitus, is a close relative of the common earthworm, found primarily in the central plains of northern America. Venerated by native Indians as a magical creature in contact with the gods, the lightning worm inhabits mainly flat plains, with little or no tall-growing plants to attract lightning strikes.
When thunderstorms approach its burrow, the lightning worm will stick out its head, stretching it straight up into the air. Adult lightning worms can reach a height of up to fifty centimeters ( ~20 inches) from their burrow, with a total length of almost two meters (six feet). The goal of this behavior, of course, is to maximize the chances of being struck by lightning.
Due to a as-of-yet poorly understood mechanism, the lightning worm is able to transform the electric energy of lightning strikes into chemical energy that its metabolism can store and retrieve freely. The surge of electrical current generated is channeled by a specialized group of cells, called “generators”. This helps to minimize cell damage to other tissues of the worm, and assures that the current only comes into contact with cells that have the capability of transforming its electric charge into a difference in potential between the outer and inner cell membrane. This difference in potential, much like the one obtained in the photosystems of plants, will then be used to turn ADP into ATP using proton pumps (for a detailed explanation of this process, please refer to the wikipedia article on photosynthesis).
Although the electrical charge in itself is not enough to ensure the survival of the worms, since it does not give them the building bricks necessary to repair damaged cells, or grow, it is critical to their reproductive success. During their mating period, lightning worms spend most of their time defending their territory or copulating, and have almost no time to find food. The energy they can gain from a lightning strike can give them a definite advantage in their quest for progeny, and evolution has favored those genes that give them an advantage in attracting lightning strikes. This is one of the reasons why lightning worms live mostly in iron-rich soils. They are capable of extracting and storing the metal in special compartments in their head, which allows them to better capture lightning.
Due to the fact that his native habitat is unsuited for agriculture, the lightning worm has been little affected by human intervention in the past century, and even today, it is not uncommon to see hundreds of lightning worms sticking their head into the air in southern Arizona, in anticipation of an electric discharge.
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