How to Build a Tiny Moss Leaf
The Creator’s handiwork
shines through the details
From One Cell to a Perfect Leaf
Evolution’s Coordination Problem
by Ronald D. Fritz, PhD
In one of the most detailed and technically sophisticated studies of plant development in recent years, Wenye Lin and colleagues combined live imaging, genetics, pharmacology, and computer modeling to meticulously track the development of moss phyllids (leaf-like organs) from a single initial cell in the model moss Physcomitrium patens. In this study, they followed the process from a single initial cell all the way to a mature, flat leaf-like structure.
Morphogenesis of moss leaf-like organs through variations in deeply shared developmental principles.1 (Lin, W., et al., Science Advances, April 15, 2026). Wenye Lin and ten other scientists demonstrate how moss phyllids (“leaf-like organs”) develop from a single initial cell into flat, functional structures through highly coordinated cellular rules, mechanical forces, and auxin signaling — mechanisms deeply shared with flowering plants.
What makes this study stand out is the remarkable level of detail: the team developed a novel time-lapse live imaging protocol — a significant technical achievement — to track hundreds of individual cells in real time. They mapped precise division patterns, measured growth rates, tested the role of auxin with drugs, and built computer models that successfully reproduced the natural flattening process.
In doing so, they uncovered a highly integrated developmental system with numerous interdependent parts that must all work together precisely to produce a flat, functional “leaf.”
For instance:
- Starting cell division: The process begins with one “tip” (apical) cell. This cell divides in very specific directions and patterns to produce a consistent number of daughter cells. These divisions are not random — they follow a precise recipe encoded in the DNA, along with mechanical feedback from neighboring cells.
- Top-and-bottom polarity: While this is occurring, the developing organ must establish clear “top” (upper) and “bottom” (lower) sides. This polarity is essential so the phyllid grows flat instead of curling or forming a tube — without it, proper photosynthesis would be impossible.
- Base-focused growth: This polarity enables controlled growth that is directed mainly from the base upward, allowing the leaf-like organ to expand evenly to the correct size and shape — equally crucial for photosynthesis.
- Auxin signaling: Running throughout the entire process, the plant hormone auxin acts as the master traffic controller. It is produced at the growing tip and flows steadily downward, creating a concentration gradient (strongest at the tip, weaker at the base). This chemical map informs when cells are to divide, when they are to stretch, and in which direction — all at precisely the right times and locations.
- Cell wall mechanics: Meanwhile, sophisticated built-in mechanical feedback between neighboring cells ensures the flexible cell walls stretch in the right directions while resisting others, preventing buckling or curling during the rapid growth.
- Precise termination: The developmental program also precisely regulates when cell division and expansion stop so the phyllid reaches the perfect final size without overshooting or undershooting.
- Multi-scale integration: And all these processes must coordinate perfectly from a single cell → groups of cells → whole tissues → the complete flat organ. It resembles a symphony orchestra where every musician and every section must play its part flawlessly, at exactly the right moment — which it does.
The researchers used live imaging to track cell division and growth in thousands of cells overall, with individual time-lapse videos following dozens to nearly 1,000 cells at a time. The results were strikingly consistent: tight patterns with very little variation in cell numbers, sizes, and shapes, even though growth is rapid and occurs in a naturally “noisy” cellular environment.
Think about what that means. Beginning with a single cell, the developing phyllid establishes where the future top and bottom of the leaf will be. The developmental program specifies where cells divide, when they stop dividing, how much each cell expands, how neighboring cells mechanically support one another, and how all of these activities remain synchronized across hundreds of cells. If any one of these systems drifts too far from the others, the flat photosynthetic organ never forms.
Remarkably, flattening succeeds with near-100% reliability starting from a single cell. To achieve this, the paper shows that auxin must be precisely distributed — the right amounts, in the right places, at the right times. Even modest experimental disruptions to the auxin gradient cause substantial defects, such as up to 50% fewer cell divisions in key directions, a shortened growth zone, and narrower, misshapen phyllids.
At first glance, this seems like exactly the kind of study evolutionists should celebrate. After all, mosses are considered among the earliest land plants. If gradual evolution built increasingly sophisticated developmental systems over millions of years, then mosses should provide one of its clearest success stories.
Instead, the study reveals something quite different.
Rather than uncovering a simple developmental program that could be gradually modified over time, the researchers found an extraordinarily integrated system in which numerous processes must operate in concert from the very first cell onward. Cell division, tissue polarity, hormone signaling, mechanical feedback, growth regulation, and precise termination are all interdependent. Remove or significantly disrupt one component, and the entire developmental program begins to break down.
The obvious question therefore becomes: How could such a tightly integrated developmental program arise through numerous small, unguided mutations while remaining functional throughout every stage of its proposed evolution? The challenge is not merely producing one beneficial mutation. It is producing dozens—or perhaps hundreds—of coordinated improvements that must all work together before the developmental system functions with the extraordinary reliability observed in this study.
The Improbability of Coordinated Assembly
To appreciate the magnitude of the challenge, consider a deliberately conservative thought experiment.
Suppose each of the seven major coordinated processes described above requires only three critical coordinated events on average—a considerable understatement—and suppose a typical phyllid contains between 500 and 1,000 cells. A single phyllid would then require roughly 10,500 to 21,000 coordinated developmental events to occur successfully.
If the developmental program succeeds 95–99.9% of the time, then the allowable error rate for each critical event must be extraordinarily low.
| 95% | less than ~ 1 error in 200,000 to 400,000 events |
| 99% | less than ~ 1 error in 1-2 million events |
| 99.90% | less than ~ 1 error in 10-21 million events |
Such reliability requires far more than simply producing the correct structures. It also requires sophisticated systems for regulation, signaling, mechanical feedback, timing, and error correction operating together with extraordinary precision.
Now consider evolution’s challenge. Even if we make an extremely generous assumption that only 100 specific beneficial mutations were required to build and maintain this level of developmental precision—and that each mutation had a one-in-a-million chance of arising and becoming fixed within the population (a commonly used illustrative assumption that is likely generous to evolution)—the combined probability is still approximately 1 in 10⁶⁰⁰.
That figure is almost beyond comprehension. The observable universe contains roughly 10⁸⁰ electrons. A probability of 1 in 10⁶⁰⁰ is incomprehensibly smaller than randomly selecting one particular electron from all of them. While this calculation is intended as an illustration rather than an exact prediction, it highlights the immense challenge of assembling such a highly integrated developmental program through a long series of unguided mutations.
Could vast amounts of time overcome this difficulty? Consider an extremely generous scenario.
- Moss generation time: approximately one month.
- Population size: one billion moss plants.
- Possible evolutionary trials each year: about 12 billion.
Even under these exceptionally favorable assumptions, a probability of 1 in 10⁶⁰⁰ corresponds to an expected waiting time of roughly 10⁵⁹⁰ years—astronomically beyond the approximately 14-billion-year age assigned to the universe.
The central problem is therefore not simply one of time. It is one of coordination. Multiple interacting systems would have to arise, improve, and remain compatible throughout countless generations while continuing to produce functional organisms. The remarkable precision documented in this study appears far more consistent with an integrated design than with a long sequence of unguided, incremental changes.
Deep Similarity Challenges Deep Time
As impressive as the developmental precision is, the paper presents a second challenge.
The authors describe “deeply shared developmental principles” between mosses and flowering plants such as Arabidopsis. Growth from the base, auxin regulation, and several key developmental genes are remarkably similar despite the evolutionary claim that these groups have been separated for more than 400 million years.
During such immense spans of time, DNA mutations continually accumulate. Direct measurements have shown that spontaneous mutation rates in plants are on the order of 10⁻⁸ to 10⁻⁹ changes per DNA base per generation.² Even though purifying selection removes many harmful mutations, hundreds of millions of years still provide ample opportunity for substantial sequence divergence to accumulate in many developmental genes, along with at least some degree of functional remodeling.
Instead, the developmental toolkit has remained strikingly conserved. Both the genetic components and their coordinated functions remain far more similar than many would expect after such immense periods of supposed evolutionary separation.
From a design perspective, this is not surprising. An engineer frequently reuses successful designs because they work exceptionally well. Likewise, a Creator could employ the same elegant developmental toolkit in different created kinds without requiring common ancestry over hundreds of millions of years.
Summary
This remarkable study highlights two observations that deserve careful consideration.
First, it reveals a developmental system requiring extraordinary coordination, precision, and reliability—qualities that are difficult to explain through a long series of small, unguided evolutionary changes.
Second, it demonstrates that the core developmental machinery shared by mosses and flowering plants has remained remarkably conserved despite the vast evolutionary timescales proposed by conventional theory.
Taken together, these findings fit comfortably within a design framework while presenting significant questions for gradual Darwinian explanations.
Conclusion
Wenye Lin and colleagues have produced an outstanding piece of experimental science. Their innovative imaging techniques provide an unprecedented view of how a seemingly simple moss phyllid develops from a single cell into a precisely organized photosynthetic organ.
Far from revealing a simple system, the study uncovers an intricate developmental program involving precisely coordinated cell division, mechanical feedback, hormone signaling, growth regulation, and spatial organization operating together with remarkable reliability.
The more scientists uncover about even the simplest living organisms, the more layers of sophisticated coordination they discover. Rather than diminishing the appearance of design, studies like this continue to reveal just how much integrated information must already exist before a single flat leaf-like organ can successfully form.
The Creator’s handiwork shines through the details.
As Kepler might say, “We are thinking God’s thoughts after Him, when we uncover such elegant systems as these.”
References
- Lin, W., Collet, L., Mancini, L., Deshpande, M., Lane, B., Lapointe, B., Bagniewska-Zadworna, A., Routier-Kierzkowska, A.-L., Smith, R. S., Coudert, Y., & Kierzkowski, D. (2026). Morphogenesis of moss leaf-like organs through variations in deeply shared developmental principles. Science Advances, 12(16), Article eaee6959. https://doi.org/10.1126/sciadv.aee6959
- Ossowski, S., Schneeberger, K., Lucas-Lledó, J. I., Warthmann, N., Clark, R. M., Shaw, R. G., Weigel, D., & Lynch, M. (2010). Direct estimate of the rate of genome-wide mutation in the higher plant Arabidopsis thaliana. Science, 327(5961), 92–94. https://doi.org/10.1126/science.1180677
Ronald D. Fritz, PhD, is a retired research statistician whose career spanned 27 years. Before entering the field of statistics, he worked as an engineer and engineering manager in the defense industry. He earned his doctorate in Industrial Engineering, with a minor in Mathematical Statistics, from Clemson University, where he was honored as a Dean’s Scholar. Dr. Fritz served as a consulting statistician across a broad range of industries, culminating in a 12-year role as a global statistical resource at PepsiCo. During his time at PepsiCo, he led significant research on gluten contamination in oats and its relationship to celiac disease, publishing several articles on the subject.
In retirement, Dr. Fritz developed a deep interest in creation science, sparked by a visit to the Creation Museum in Petersburg, Kentucky. As he delved into the topic, he shared his findings with his pastor, which led to an invitation to speak at their church. This initial presentation opened the door to further speaking engagements at churches throughout the region. Dr. Fritz has been married for 35 years to his wife, Mitzie. They live in the mountain community of Bee Log, North Carolina, within sight of the church where they were married and now worship. In his free time, Dr. Fritz tends a small chestnut orchard on their property, working to revive what was once a cherished local delicacy. The couple has two adult children.