The Design of Cacti

There are 1,500 known species of cacti on our planet, and many live in places so dry and hot that it is hard to imagine any life surviving. Cacti can branch out as massive trees or be small enough to fit on a penny. Scientists are studying the design of cacti to find ways to apply their ability to survive heat and conserve water.

The saguaro cactus, which grows in the Sonoran desert of Arizona, California, and Mexico, can retain hundreds of gallons of water. These plants have pleats that expand to hold the water when rain comes. Saguaro cactus flowers bloom from mid-April to mid-June. They boom only once at night and close the next day, protecting them from the Sun’s intense heat. The flower buds are on the crown of the cactus and bloom in a counterclockwise migrating pattern from the east to the north, giving them more shade as the season becomes hotter.

Saguaros have a unique way of photosynthesis. Most plants lose water as they open their pores to absorb carbon dioxide. Saguaros do not open their pores until after sundown. Then, they absorb carbon dioxide and convert it into malic acid, which they store in their cells for the next day. The design of cacti shows great wisdom and efficiency in the use of resources.

Copiapoa cacti thrive in the Atacama desert of northern Chile, the driest nonpolar desert on Earth. Most copiapoa cacti are 5 to 6 inches in diameter and covered with spines. Every morning, as fog sweeps in from the sea, water condenses on the spines and skin of these plants. The spines have a series of tiny grooves that broaden at the base, enabling the cactus to channel moisture into itself. Scientists are looking at the possible use of this design for dew-collecting in areas with water shortages.

As scientists study cacti, they look for ways to use their hot and dry climate adaptations to solve some of the problems agriculture faces with extreme heat. Biomimicry is a process in which we study the plants and animals God created and use what we learn to improve our lives. Proverbs 6:6 says, “Go to the ant, thou sluggard; consider her ways, and be wise.” The principle is clear. We can learn by studying the design God built into all living things, including the design of cacti.

— John N. Clayton © 2024
Reference: National Geographic November 2024, pages 88-99.