What if a simple sea sponge could spark a debate about the origin of animal life? A recent study suggests that some of Earth’s earliest animals were sponge-like creatures due to chemical traces found in ancient rocks.¹ Researchers discovered unusual sterane molecules in marine sediments. Steranes are chemical traces that form when sterols—lipid molecules that help strengthen cell membranes—break down over time. Since modern sponges produce these sterols, scientists concluded that the molecules may record the early history of animal life. But the discovery may point to a different lesson. When we examine the biology behind these molecules, we see systems that work with strong coordination and order—features unexpected from evolved systems but often seen in engineered systems.

The study focuses on steranes preserved in sedimentary rocks. Modern demosponges (one of the most common groups of sea sponges) produce a distinctive sterol. Over time, this sterol can break down into a molecule called 26-methylstigmastane. When scientists detected this compound in supposedly ancient rocks, they suggested sponge-like animals might have lived long before most other animal groups.¹ A research release from the Massachusetts Institute of Technology described these molecules as “chemical fingerprints” that may point to early animal life.²

Chemical biomarkers can give clues about past life, but they are only chemical traces left after organisms break down, not fossils that show direct evidence of their body structure. Scientists assume that if a molecule looks like one made by modern sponges, then a similar organism must have made it long ago. This idea depends on an important assumption: only sponges can produce this compound.

However, that premise is still uncertain. Some studies suggest that other organisms may produce sterols or related compounds that leave similar traces in sediments.³ If several organisms can make similar molecules, the biomarker alone cannot prove which organism produced it.

The molecules themselves reveal another key point: sterols do not form by chance. Rather, cells build them through many chemical steps, each of which uses a special enzyme that must work in the correct order for the process to succeed. If one step fails, the whole pathway may stop. From an engineering point of view, this system works much like a production line.

Sponges also show more complexity than many people expect. Their bodies contain cells that move seawater through tiny canals, and the water enters the sponge via small pores. Inside, chambers filter tiny food particles from the water. Other cells then move nutrients through the body. This system filters food, removes waste, and keeps the sponge stable.

These traits illustrate the difference between biological flexibility and biological limits. Sponges can vary in size, shape, and growth depending on their environment. Such flexibility helps them live in many ocean settings. Yet their core systems remain the same, and fundamental processes such as sterol production and water flow stay stable.

Engineers often recognize design when many parts work together in a connected system.⁴ Living organisms show the same kind of coordination—their parts work together to perform tasks that sustain life.

The Bible reminds us that studying nature can reveal the skill behind it. “The works of the LORD are great, studied by all who have pleasure in them” (Psalm 111:2). This biomarker discovery fits this line of reasoning. Ancient molecules preserved in marine rocks show that ocean life had complex biochemical systems. Rather than explaining how these systems began, the evidence highlights the remarkable design found even in organisms that appear simple.

References

1. Shawar, L. et al. 2025. Chemical Characterization of C₃₁ Sterols from Sponges and Neoproterozoic Fossil Sterane Counterparts. Proceedings of the National Academy of Sciences. 122 (41).
2. Massachusetts Institute of Technology. MIT Study Finds Earth’s First Animals Were Likely Ancient Sea Sponges. ScienceDaily. Posted on sciencedaily.com February 27, 2026.
3. Zumberge, J. A. et al. 2018. Demosponge Steroid Biomarker 26-Methylstigmastane Provides Evidence for Neoproterozoic Animals. Nature Ecology & Evolution. 2 (11): 1709–1714. 
4. Guliuzza, R. J. 2010. Similar Features Demonstrate Common Design. Acts & Facts. 39 (11): 10–11. 

Stage image credit: Bigstock | mychadre77. Used in accordance with federal copyright (fair use doctrine) law. Usage by ICR does not imply endorsement of copyright holder.

* Dr. Corrado earned a Ph.D. in systems engineering from Colorado State University and a Th.M. from Liberty University. He is a freelance contributor to ICR’s Creation Science Update, works in the nuclear industry, and is a Captain in the U.S. Naval Reserve.