In recent years, people have paid a great deal of attention to insects and how they benefit humans. Some insects pollinate our fruit trees. Others provide food for birds and a variety of mammals–even humans. Insects also help convert waste into valuable nutrients. One of the dangers to the total insect population is over predation because so many animals eat them. One insect species solves the problem in a unique way. It is the periodic cicada or Magicicada that appears every 17 years. These insects suddenly emerge from the ground in massive numbers, as many as 1.5 million per acre, to overwhelm their predators.
Dr. Cliff Sadof of Purdue University has headed up research into the life cycle of cicadas. He tells us why we will have a massive amount of noise during the coming weeks from treetops all around us here in Indiana and other areas of the eastern United States. When the soil temperature reaches 64 degrees F at a depth of eight inches, the periodic cicada or Magicicada will start crawling out of the ground. In massive numbers, they climb up trees to molt. After molting, their bodies will be white as they unfold new wings. In a few hours, their bodies will harden, and the males will fly into the treetops and start singing to attract females.
After mating, the females will lay eggs in twigs with a saw-like egg-laying device called an ovipositor. After the eggs hatch, the nymphs will fall from the treetops and burrow into the ground, where they feed on sap from the tree roots. Seventeen years later, the nymphs will emerge and become adult cicadas repeating the cycle.
The cicadas are easy to see, good to eat, and plentiful in huge numbers. Birds, squirrels, and other insect-eating animals will gorge on the cicadas giving other insects a reprieve to recover their numbers. The soil around the trees will be aerated and enriched. The process will prune upper tree branches encouraging new growth.
In Indiana and many other states, the cycle is 17 years. In other regions, the periodic cicada or Magicicada has a 13-year cycle. Trying to explain how such a system came into existence by chance requires a tremendous amount of imagination. We suggest that cicadas are another example of wisdom built into the natural world by God to allow life to exist on planet Earth.
— John N Clayton © 2021
Our thanks to David Harrington, who sent us this information from the Herald Bulletin in Anderson, Indiana.