Diatoms Are Essential for Life on Earth

We seldom think about the importance of microscopic organisms. Diatoms are essential for life on Earth because they generate 20-30% of the oxygen we breathe. They are single-celled algae with a cell wall made of silica. In March 2022, the National Science Foundation announced the discovery of two unique diatom species in the waters around Hawaii.

Diatoms live in the oceans and waterways. You may be familiar with diatomaceous earth, which has many commercial uses, including pest control in organic gardening. It consists of the empty silica shells that diatoms leave behind. In addition to generating oxygen, diatoms are essential for life as part of the food chain in the oceans.

Like green plants, diatoms need nitrogen to grow. Marine diatoms thrive in nutrient-rich ocean areas such as the Gulf of Mexico. However, the open ocean waters around Hawaii lack significant nitrogen nutrients. Ocean waters contain dissolved nitrogen gas, but the diatoms can’t use it. These two species of diatoms solve that problem by having a symbiotic relationship with nitrogen-fixing cyanobacteria. These bacteria do not contain chlorophyll for photosynthesis, but they can extract nitrogen from ocean water and convert it to ammonia. In turn, the diatoms can use the nitrogen from the ammonia. In a symbiotic relationship, the newly discovered diatom species take the nitrogen-fixing bacteria into their shells to nurture their own personal nitrogen generators.

We have mentioned many symbiotic relationships before, but here is a microscopic one. Diatoms are essential for life because they provide much of the oxygen we breathe. This symbiotic relationship between diatoms and bacteria is another example of God’s wisdom and design for life. Everywhere we look, we see that God has designed and implemented systems that sustain life in all kinds of environments.

— John N. Clayton © 2022

Reference: National Science Foundation