In southern Indiana right now we are witnessing one of the greatest biological events known to humans. Trillions of periodic cicadas (pictured above) are coming to the surface and crawling out of their subterranean homes where they have been living for 17 years. Brood X is the largest group of 17-year periodic cicadas and they can emerge at a density as high as 1.4 million per acre of land. They require woody trees for their lifecycle, so southern Indiana, where there are hundreds of square miles of national forest, is their prime territory. The red-eyed, 1.5 inch long bugs are basically defenseless but their survival strategy is effective – they simply overwhelm their predators with their numbers. In the forests around us, the amount of cicada biomass can reach around 800 tons per square mile. It is an astounding natural phenomenon, and it only happens once every 17 years for this brood.
The juvenile cicadas crawl out of the ground and climb onto a vertical structure – biological or otherwise – where they complete their final molt and emerge as adults with new wings (obviously not needed underground). After their exoskeletons dry, they fly up into the trees where the males begin to make a loud noise calling for potential mates. A single male cicada is able to make a noise as loud as 100 decibels, which is as loud as a gas-powered lawn mower. In a cicada-dense area, the noise can be deafening. While the cicadas do not eat the vegetation during their short (4-6 week) life above ground, females damage the small branches of deciduous trees when they deposit their eggs. In about 10 weeks’ time, the eggs will hatch and the nymphs will drop to the ground and burrow underground where they will remain until 2038.
In the middle of this event it is hard to imagine that trillions of large bugs have been underground living on the sap of tree roots for 17 long years only to emerge, mate, and die in a 4-6 week period. The cicadas have no defense mechanisms and no ability to fight off predators. They don’t even seem particularly interested in fleeing from predators. They simply depend on coming out in such great numbers that their predators, of which there are many (including domestic dogs and cats), cannot possibly eat them all. That approach has allowed them to survive for generations. They were going strong over 400 years ago when the Pilgrims came to Plymouth Rock.
For those who have the eyes (and the ears) to see (and hear) it, this incredible natural phenomenon ought to cause us to pause and marvel at the handiwork of God. Brood X (and others like it) comes out exactly on cue every 17 years while other broods come out every 13 years. The various 13-year broods remain isolated from each other as do the various 17-year broods, and the simultaneous emergence of any 13-year brood with any particular 17-year brood will happen every 221 years. This pattern keeps the various broods distinct and yet highly coordinated with their kin in a local area. It is almost as if it were planned that way!
When the Bible encourages us to marvel at the works of God, it often points us to His “wonders.” In scripture this is a specific reference to the miracles of the 10 plagues, in which God showed His power in the deliverance of His people from their masters in Egypt. It is easy for us to forget that the same power He used to turn water into blood and to cause a swarm of locusts to descend on the enemies of His people is at work in the regular patterns we see all around us. The seasons follow each other in turn. The rains fall. The crops grow. The flowers bloom. The leaves turn colors and fall to the ground. It is easy to think all of those things just happen “on their own” but, of course, they don’t!
These regular patterns happen because God is always at work through His Son to sustain and care for His creation until the day that Jesus returns to consummate His kingdom (Colossians 1:15-18). In the meantime, we need to learn to see and receive the reminders of God’s power and care for us in the regular patterns of nature. The emergence of Brood X is certainly a graphic reminder that God works powerfully in His world to care for and sustain even the lowliest of creatures – those who have to live in the dirt for 17 years just to get a few weeks in the light. How much more will He care for and sustain His people whom He has purchased with His own blood (Acts 20:28). If you are fortunate enough to be able to witness this current display of God’s handiwork, rather than being repulsed because there are so many bugs around, pause to give your Creator praise for His work in the world and in your life!