The Spiny-Skinned Passion of Hans Hess: A Life Unearthed
How a pharmaceutical executive revolutionized paleontology in his spare time
Introduction: The Man with Two Lives
Imagine a respected pharmaceutical executive, responsible for developing life-saving medications, who then goes home to meticulously clean 30,000 microscopic fossil fragments. This was the extraordinary dual existence of Hans Hess (1930-2017), a man whose professional life centered on modern medicine but whose heart belonged to ancient sea creatures.
Pharmaceutical Career
Earned his PhD in 1958 and worked at CIBA (later Ciba-Geigy) developing medications.
Paleontological Passion
Volunteered at the Natural History Museum of Basel and became a world authority on fossil echinoderms.
For over six decades, Hess pursued fossil echinoderms—the spiny-skinned animals including sea stars, sea urchins, and crinoids—with relentless passion. Without formal paleontological training, this self-taught researcher became one of the world's leading authorities on fossil echinoderms, producing work so exceptional that the University of Basel awarded him an honorary doctorate and scientific societies across the globe honored his contributions 1 .
"Hans had the remarkable talent, energy, and persistence to accomplish two careers" 1
What Are Echinoderms?
Before diving into Hess's contributions, it's essential to understand the fascinating creatures that captured his lifelong interest.
Echinoderms (from the Greek echinos for "spiny" and derma for "skin") represent one of the most distinctive phyla in the animal kingdom 2 . They include familiar marine animals like:
- Sea stars (starfish)
- Brittle stars
- Sea urchins and sand dollars
- Sea cucumbers
- Crinoids (sea lilies and feather stars) 5
Living echinoderm species
Extinct echinoderm species
Unique Biological Features
Pentaradial symmetry
Their bodies are typically arranged in five parts around a central axis 6
Calcareous endoskeleton
An internal skeleton composed of ossicles (small plates) made of calcium carbonate 6
Remarkable regeneration abilities
Many can regrow lost body parts 6
What makes echinoderms particularly valuable to paleontologists is their well-preserved fossil record. Their calcareous skeletons fossilize readily, providing crucial insights into ancient marine ecosystems 6 .
Hess's Paleontological Journey
Early Passion to Prolific Contributor
Hess's fascination with fossils began in childhood. As a schoolboy in Basel, Switzerland, he collected fossils with friends, publishing his first scientific paper at just 21 years old—the description of a stemless crinoid he named Paracomatula helvetica 1 .
Despite pursuing a career in pharmacology (he earned his PhD in 1958 and joined the pharmaceutical company CIBA, later Ciba-Geigy), Hess never abandoned his paleontological interests. He maintained a volunteer position at the Natural History Museum of Basel (NMB) throughout his adult life, eventually assembling one of the world's finest collections of Jurassic crinoids now housed at the museum 1 .
A Methodological Revolution
Hess's most significant contribution to paleontology may have been methodological. He recognized that traditional approaches of collecting only complete, visible specimens created a biased fossil record. While others sought perfectly preserved specimens, Hess understood that greater treasures lay hidden in seemingly unpromising sediments.
His breakthrough came when he began processing large amounts of weakly consolidated sediments to extract disarticulated echinoderm ossicles (individual skeletal elements). This technique, which he pursued for nearly 15 years, revealed an astonishing diversity of microscopic fossil elements that had been overlooked by conventional collection methods 1 .
Hess's Major Research Focus Areas
| Research Area | Significance | Key Contributions |
|---|---|---|
| Jurassic echinoderms of Switzerland | Established baseline understanding of regional echinoderm diversity | 1975 book still the standard reference for fossil collectors |
| Bajocian Hauptrogenstein Formation | Exceptionally rich crinoid beds | Sampled repeatedly over decades; material fills 125 museum drawers |
| Fossil ophiuroids (brittle stars) | Applied novel sediment processing techniques | Revealed previously unknown diversity through disarticulated remains |
| Stalked crinoids | Focus of his later years | Revised classification in Treatise on Invertebrate Paleontology |
Key Milestones in Hess's Career
1951
Published first scientific paper at age 21 describing Paracomatula helvetica
1958
Earned PhD and began pharmaceutical career at CIBA
1960s-1970s
Developed sediment processing techniques for microfossils
1975
Published seminal work on Jurassic echinoderms of Switzerland
1980s-2000s
Continued research while working full-time in pharmaceuticals
2017
Passed away, leaving a legacy of groundbreaking paleontological research
The Sieve Method: Hess's Key Experiment
Background: The Problem of Incomplete Fossils
Traditional paleontology favored collecting complete, well-preserved specimens. This approach, however, overlooked the vast majority of echinoderm remains. When echinoderms die, their skeletons—composed of numerous individual ossicles held together by soft tissue—quickly disarticulate into countless fragments 6 . Conventional collection methods missed these fragments, creating gaps in our understanding of past biodiversity.
Methodology: Step-by-Step Sediment Processing
Hess developed and refined a technique that revolutionized the study of microscopic echinoderm remains:
Field Collection
Gathering large quantities of weakly consolidated sediment from fossil-rich localities
Sediment Disaggregation
Gently breaking down sediment using water and mild chemical treatments
Sieving
Passing sediment through fine mesh sieves to separate fossil elements by size
Microscopic Analysis
Systematically examining material under magnification to identify ossicles
This process required extraordinary patience. For the Pliensbachian of Arzo site alone, Hess sorted through nearly 30,000 isolated ossicles to reconstruct 30 crinoid species, 16 of which were new to science 1 .
Results and Analysis: Hidden Diversity Revealed
Hess's sediment processing technique yielded spectacular results that transformed understanding of Jurassic marine ecosystems:
| Metric | Finding | Significance |
|---|---|---|
| Total ossicles examined | ~30,000 | Demonstrated value of high-effort methodology |
| Crinoid species reconstructed | 30 | Revealed unexpected diversity |
| New species identified | 16 | Greatly expanded known biodiversity |
| Research duration | Multiple years | Highlighted method's labor-intensive nature |
The scientific importance of this work extended far beyond adding new species to catalogs. By demonstrating that rich fossil assemblages could be recovered from seemingly barren sediments, Hess opened new avenues for investigating ancient ecosystems. His approach allowed paleontologists to study environments previously considered poor fossil sources and provided statistical data for analyzing biodiversity patterns through time 1 .
The Scientist's Toolkit: Echinoderm Research Essentials
Hess's work, and echinoderm paleontology more broadly, relies on specialized tools and materials. Here are the key components of the echinoderm researcher's toolkit:
| Tool/Technique | Primary Function | Application in Hess's Research |
|---|---|---|
| Fine sieves | Separate microscopic fossils from sediment | Critical for recovering disarticulated ossicles |
| Binocular microscope | Examine minute morphological details | Essential for identifying fragmentary specimens |
| Weak acid solutions | Dissolve carbonate matrix without damaging fossils | Process limestone sediments to release fossils |
| Illustration tools | Document delicate morphological features | Collaborated with scientific illustrator Otto Garraux |
| Comparative collections | Reference for identifying unknown specimens | Built extensive personal and museum collections |
| Sediment processing equipment | Break down consolidated materials | Enabled bulk sampling methodology |
| Scanning Electron Microscope (SEM) | High-resolution imaging of microscopic structures | Used in later career for detailed ossicle examination |
Patience and Precision
Hess's methodology required extraordinary attention to detail and persistence. Processing thousands of microscopic fragments demanded both technical skill and unwavering dedication.
Collaborative Approach
Despite working primarily as an independent researcher, Hess collaborated with illustrators, museum curators, and other scientists to ensure the accuracy and impact of his work.
Legacy and Lasting Impact
Hans Hess continued active research until his death in 2017, even announcing his leukemia diagnosis to colleagues with characteristic pragmatism and determination to complete ongoing projects 3 . His final publications continued to break new ground, exploring the origins and evolution of specialized crinoid groups.
The scientific community honored Hess's memory with a special issue of the Swiss Journal of Palaeontology, where colleagues described him as "an outstanding palaeontologist and a fine man" 4 . Perhaps most touchingly, several newly discovered fossil taxa were named in his honor, including:
Trombonicrinus hanshessi
A Devonian crinoid with an unusually coiled stem 4
Eocenocrinus hessi
An Early Eocene stalked crinoid 4
Hanshessaster
A new genus for a Western Atlantic crinoid species 4
Hansaster
A Jurassic asteroid (sea star) 4
These taxonomic tributes ensure that Hess's name will remain permanently embedded in scientific literature, much like the fossils he so cherished are embedded in stone.
The Power of Passionate Curiosity
Hans Hess's story transcends the conventional narrative of a specialist dedicating their life to a single field. Instead, he exemplifies how diverse interests can cross-pollinate to produce extraordinary outcomes. His pharmaceutical training likely contributed to the meticulous, systematic approach that made his paleontological work so impactful.
More importantly, Hess demonstrated that major scientific contributions don't always come from career academics. As a volunteer researcher who pursued paleontology for pure love of the subject, he published extensively, mentored younger scientists, and built collections that continue to support research worldwide.
His life reminds us that passion, when coupled with rigor and patience, can reveal worlds hidden in plain sight—whether in a pharmaceutical lab developing future medicines, or in ancient sediments preserving echoes of life from 170 million years ago. The microscopic crinoid ossicles that might have been overlooked as insignificant became, through Hess's vision and dedication, windows into lost marine worlds.