Amazing ammonite animatronics!

by Gavin Cox

Ammonites are extinct marine cephalopods, relatives of modern nautiloids, squid, and octopi. Researchers from the Department of Geology and Geophysics, University of Utah, USA, have recently gained greater insights into how they got around ‘long ago’.

Figure 1. (Left) Lower Jurassic ammonite Pleuroceras solare from Germany, showing serpenticone whorls (Credit: Wikimedia/ Llez (H. Zell)).
Figure 2. (Right) Asteroceras obtusum, Ammonite from the Early Jurassic depicted alive (Credit: Wikimedia/ Nobu Tamura).

You are probably familiar with fossil ammonites, classically found along the Jurassic Coast of England. Their lovely spiral whorls look a bit like coiled snakes (figure 1); and there are other types with different shapes. In life, they would have been similar to the modern nautilus and its cousin the ‘paper nautilus’ (see Amazing Argonauts). They had tentacles protruding from the shell’s opening, along with their head, mouthparts, eyes, and syphon (figure 2), with which the animal propelled itself backwards, using jet-like pulses of water.

But how well did they swim, when they look so ungainly?

Now, thanks to a lot of clever 3D model printing and animatronic wizardry—more technically ‘biomimetic’ (mimicking biology) robotics—scientists have likely figured out how these mysterious creatures got around in the oceans of a by-gone era. In secular thinking this was the so-called Jurassic era (201–145 million years ago), which in biblical terms is part of the ‘pre-Flood era’. Releasing their robot creations into a swimming pool and a flow-tank, they carefully monitored and filmed them.1 The researchers published their findings in Scientific Reports outlining their methods and results which are thought to mimic the movements in water of these fascinating extinct creatures.2

Ingenious engineering

Various hollow models of ammonites were created using a process called 3D printing, which casts a resin shape via a specialized 3D printer machine from computer instructions. The advantages of such construction methods are many, but primarily, such devices can construct accurate and highly complex shapes easily, using very cheap materials (plastic). The ammonite models were made to vary according to the possibilities inherent in the shell morphology, and seen within the fossil record. Three major forms were identified: (a) serpenticone (tight whorls, narrow shell), (b) oxycone (thick whorls, narrow, streamlined shell), (c) sphaerocone (few thick whorls and wide, nearly spherical shell); a fourth variable (d) termed ‘morphospace center’ equates to the overall centers of buoyancy and mass (of the average ammonite) (figure 3). These four points (shown as end members and central point on a triangular diagram) could be varied to any degree, to see which forms had the best hydrodynamic performance (measuring drag, wake dynamics,3 and turbulence). Interestingly, it was found that no particular shape had any more advantages on balance than other variations—they all appeared to be (from an engineering perspective) shapes well designed to float, or swim, while staying vertically oriented in water.

David J. Peterman & Kathleen A. RitterbushBiomimetic-ammonites
Figure 3. Biomimetic ammonites with propulsion and sensor apparatus, showing three fundamental forms: (a) Serpenticone, (b) oxycone, (c) sphaerocone, and (d) morphospace center.

The various shaped shells were packed with clever battery-powered robotics, mimicking the jets that modern nautiloids produce. Infrared sensors were also placed inside the models to check orientation, acceleration, coasting efficiency, jetting dynamics, hydrodynamic stability, maneuverability, and moment of inertia.4 Each model was carefully calibrated, so that no one shape had any competitive advantages in terms of thrust. The final biomimetic robot with all its parts was water-tight and neutrally buoyant, meaning it neither sank, nor floated, but could easily maneuver, like the real thing.3

The results of the investigation were plotted5 and mathematically modelled, demonstrating a trade-off between hydrodynamic stability and yaw maneuverability (rotation around the vertical axis) (figure 4). The researchers recognized this meant there were advantages for different environments. This in their words means there is: “no single optimum conch [shell] morphology” and “… there is no morphology that is universally adapted to being the “best” swimmer.”2

David J. Peterman & Kathleen A. Ritterbushammonite-shapes_a-d
Figure 4. Graphs of velocities plotted for all four ammonite shapes a-d.

Earlier research done on another variety of straight shelled (orthocone) cephalopod, demonstrated that, surprisingly, they would have lived in the vertical orientation (heads pointing downwards), not horizontal, as previously thought.6

Design paradigm

Throughout the report the researchers constantly use design language to describe their research, for instance:

“Biomimetic cephalopod robot design …”

“We designed 3D-printed, biomimetic robots …”

“This system was optimized by iteratively designing models …”

“These robots were engineered …”

Such language implies clever forethought, planning, organizing, and implementing of plans by intelligent agents (human scientists), in order to manufacture complex systems. None of this happened by chance, or random processes over indeterminate periods of time. Every step was managed and monitored to achieve desired outcomes—the very essence of good, operational science. Indeed, as we often point out about operational/experimental science (as distinct from historical science), the team’s work was repeatable, observable, and measurable—all done in the here-and-now.

Inconsistent evolutionary thinking

However, when it comes to the extinct organisms the scientists were trying to copy (whose complexity is far greater by multiple orders of magnitude), an entirely different world-view of ‘methodological naturalism’ (no design) comes into play. This was seen with the scientists’ own descriptions of the ammonites’ origins and complex biology, and in reports of their study. A few of many examples are:

“The fossil record documents how life evolved …”

“… animals that were key components of marine ecosystems for hundreds of millions of years.”2

“[ammonite] properties make them excellent tools to study evolutionary biomechanics …”7

“… evolutionary processes that have shaped them.”7

“Evolution dealt them a very unique mode of locomotion …”7

“Throughout their evolution [ammonites] endlessly experiment[ed] with variations on the shape of their coiled shells …”7

The inconsistency of such thinking should be glaringly obvious. Evolution is not observed to happen today, neither can blind, random processes produce anything. The latter examples therefore amount to faith statements, rather than scientific conclusions. The robotic systems, though ingenious and complex, are really a pale shadow compared to the masterful designs observed in the original ammonites. The researchers could only mimic a tiny fraction of the ammonites’ swimming abilities. When it comes to all the other abilities of these extinct creatures—i.e., to metabolize their food, sense their environments, grow, heal, or reproduce themselves—the scientists would be left scratching their heads. Furthermore, even ammonite internal organs have been discovered, demonstrating their complexity.

Natural selection is also invoked within the research:

“… these animals have evolved solutions to the challenges imposed by environmental crises and day-to-day natural selection …”

“… we remain uncertain whether the locomotion potentials of disparate conch morphologies were ever first-order controls on ecology, or an unavoidable target of natural selection.”2

“Natural selection is a dynamic process, changing through time and involving numerous functional tradeoffs and other constraints …”7

In this research and modelling, the selection was done intelligently, not left to chance—it was not natural selection! These scientists should realize that natural selection can only play the hand it is dealt—it cannot add new information specifying for complexity that doesn’t already exist. However, natural selection, post-Fall, almost certainly did produce much variation within the cephalopod created kind which includes ammonites, as per the creation account (Genesis 1:20–23).

In which case, the amazing variety within the ammonite kind can be explained in terms of natural selection working on the existing genetic potential already pre-programmed. The minor variations in whorl shape, and shell designs seen within the fossil record8 all suit their particular environments. God is a God of variety and loves diversity within His creation.


Ammonites were buried along with many other marine and all land creatures not on board the Ark during Noah’s Flood, nearly 4,500 years ago. Ammonites were specially created by God on day five of creation week along with all the other swimming (and flying) creatures to fill His newly created world, declared “very good” one day later (Genesis 1:31). Ammonites were well suited to their environments, and, after the Fall, could adapt to new environmental pressures, according to their existing genetic programming.

The ability of ammonites to swim, as studied by the scientists in this latest research, demonstrates their optimal design at the hand of the Creator. Properly considered, the clever biomimetic robot creations of the scientists provide no encouragement to believers in evolution. These ingenious hydrodynamic experiments actually demonstrate the genius of the Creator’s original biological designs. Nevertheless, we also observe the blatant inconsistency of describing human-made systems as ‘designed’, but biological systems (vastly more complex) as ‘evolved’.

These clever scientists need to humbly recognize the greater designs of the Designer and give Him the praise due His name.

Published: 8 December 2022

References and notes 

  1. For interested readers, a 14-second youtube video, published by the researchers, shows a robotic ammonite swimming: Science X, Robotic ammonites recreate ancient animals’ movements, youtu.be/ZAYCGALNw64, 5 Jul 2022. Return to text.
  2. Peterman, D.J. & Ritterbush, K.A., Resurrecting extinct cephalopods with biomimetic robots to explore hydrodynamic stability, maneuverability, and physical constraints on life habits, Scientific Reports 12:11287, 2022 | doi.org/10.1038/s41598-022-13006-6. Return to text.
  3. The wake is the turbulence that forms around and behind a body moving through water (or air). Return to text.
  4. A quantity that determines the torque needed for a desired angular acceleration about a rotational axis, or turning force, measured in kilogram metre squared (kg·m2), or pound-foot-second squared (lbf·ft·s2). Return to text.
  5. The ammonite shapes (a-d) were plotted for their 3D positioning, velocities, yaw, and angular velocity. Return to text.
  6. University of Utah, 3D printed replicas reveal swimming capabilities of ancient cephalopods, phys.org/news/2021-07-3d-replicas-reveal-capabilities-ancient.html, 16 Jul 2021. Return to text.
  7. Gabrielsen, P., Robotic ammonites recreate ancient animals’ movements, phys.org/news/2022-07-robotic-ammonites-recreate-ancient-animals.html, 5 Jul 2022. Return to text.
  8. Ammonite shell external decoration includes: ribs, keels, spines, nodes, tubercles, as well as aperture variations, including: varices, constrictions, lappets, and rostra. All of these additional modifications would have hydrodynamic considerations not yet modelled by the researchers. Return to text.

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