Bernhard Bock, Phyletisches Museum Jena

Trapped in Time – Amber Discoveries

In 2021, in the dusty attic of Jena’s Phyletisches Museum, almost hidden at the back of a shelf, Bernhard Bock, collection manager at the University of Jena, found three boxes of unpolished amber. With a small group of colleagues, he sets off in search of clues. A cash receipt and typewriting on some labels provides clarity: The collection was acquired by Dr. Eduard Uhlmann, conservator, and later Director of the Phyletisches Museum until his retirement in 1954. 15 years later he bequeathed the small collection to the then custodian Dr. Dietrich von Knorre, who had stored but never had time to study it. Most likely since that time nobody had touched this box for decades. However, the origin of the amber was still a mystery.

Daniel Troeger | Phyletisches Museum Jena

What we found most exciting was the mysterious history around this amber collection and the potential of exploring undescribed species hidden in there.

Daniel Troeger | Phyletisches Museum Jena

Amber Collection, Phyletisches Museum Jena

Where to Start?

First, it was essential to further clarify the provenance of the collection. While identifying inclusions, the team got suspicious as some trapped insect did not match the information of origin on the corresponding label. It was now of highest priority to verify which piece was real amber, copal, or even artificial resin. Amber and copal differ greatly in their age, the latter one only being a maximum of 2.5 million years old, the former being as old as 300 million years! Both are tree resins that had been buried for years. Pressure and heat from sediments and other processes have hardened and polymerized the resin. Copal that stays buried and doesn’t decay for millions of years becomes amber. Finding the dividing line is not so simple, as you cannot see the age.
After simple standard testing methods – such as placing amber pieces in salt solution (will float if real), inflaming it (different colors of smoke), placing it in acetone and checking for solubility, UV lighting, etc. – did not really succeed, they decided to contact the International Amber Association in Gdansk, Poland for support, as some inclusions in pieces made the group wonder whether they were true amber or not. Through spectroscopy (FTIR, Fourier Transform Infrared Spectroscopy), they were able to ascertain which sample was copal or amber. The result showed most of the differently sized pieces were never really identified and thus mislabeled. Now there is clarity about which piece is Baltic amber and which not, but they still bear a lot of hidden secrets.

Amber inclusions | Phyletisches Museum Jena

Amber is like an eternal prison for these species.

Bernhard Bock | Phyletisches Museum Jena

Crystal Coffin

Fossils embedded in amber are called inclusions and are considered a unique natural phenomenon. Like a crystal coffin, the still liquid resin encloses living organisms, hardens, and traps them for millions of years, allowing us three-dimensional observation of their finest structures. Inclusions differ from other fossils since the animals usually get stuck in the resin while alive. This offers us a snapshot of life in motion, namely the last seconds, including their death struggle. Therefore, amber inclusions are the perfect collection objects; by themselves being caught and preserved at a certain place and a certain time.
To be able to see what’s hidden inside, Bock and his colleagues had to go through a tedious process of polishing every single piece. They first sanded the surface with progressively finer grits of sandpaper and then applied a special paste and/or activated charcoal toothpaste to the surface afterwards. In some of the pieces more than 100 fascinating inclusions came to light: Ants, beetles, bees, booklice, and many more. To isolate some rare specimen, they even cut some pieces into thinner slides.

Bernhard Bock, Phyletisches Museum Jena

There’s a lot going on in every single piece – like its own cosmos, a snapshot of times gone by.

Bernhard Bock | Phyletisches Museum Jena

Glimpse into the Past

Amber exceptionally preserves insects and microorganisms. These fossils not only provide details about an organism’s morphology, ecology, ethology, and evolutionary history, even Earth history, but are also vital to the study of climate and faunistic change that goes along with it. Some of the species buried in amber might even no longer exist today or have adapted to today’s environment. Looking back in time helps to put today’s species and their evolution into perspective.
Both the inclusions and the amber itself are of great interest for research disciplines such as zoology, botany, paleontology, and geochemistry. Amber collections are therefore a valuable part of our scientific, cultural, and global heritage.

Amber under the stereo microscope | Phyletisches Museum Jena

Amber under the Microscope

The inclusions can mostly be seen with the naked eye. But when it comes to determining species, a peek under the microscope can shed some light. Using light, stereo, and zoom microscopy as well as CT scanning technology, the team was able to discover many known species as well as two new ones. One of the finds was the best-preserved ant that has been found so far.

Revealing Ants in Amber

Images acquired with a ZEISS stereo microscope

Ant | Amber Collection Phyletisches Museum Jena
Ant | Amber Collection Phyletisches Museum Jena
Ant | Amber Collection Phyletisches Museum Jena

New Findings

Daniel Troeger was able to discover a new beetle species based on morphological characteristics visible under the microscope, and Michael Weingardt found a new booklice species that will be named after the former custodian of the Phyletic Museum von Knorre, to whom the amber collection can be traced back to.
Based on morphological characteristics, such as tiny spines, hairs, and scale patterns only visible under the microscope, the team of the Phyletisches Museum will describe further new species in the Baltic amber and copal.

Amber Worlds | Exhibition Team Phyletisches Museum Jena
Copyright: Jens Meyer | University of Jena

From left to right: PhD students Daniel Troeger and Michael Weingardt, former custodian and biologist Dr. Dietrich von Knorre and Bernhard Bock, collection manager, during the construction of the exhibition "Electrum Mundi (Amber Worlds)".

Electrum Mundi (Amber Worlds) – an Exhibition

From November 9, 2023, an exhibition called “Electrum Mundi (Amber Worlds)” in the Phyletisches Museum Jena tells the story of this fascinating amber collection and the new findings, and informs the public about the scientific significance of amber.

Find more information on the exhibition here.

Jena Phyletic Museum
Copyright: Gunnar Brehm

The façade of the Art nouveau building, itself a cultural monument, is adorned with two important terms which Haeckel coined in Jena: Ontogenie (ontogeny) and Phylogenie (phylogeny).

Phyletisches Museum Jena

Founded by Ernst Haeckel, the Phyletisches Museum Jena is a globally unique institution. It is not just a natural history museum, but a place dedicated to illustrating the development of life. Its main areas of focus are phylogeny and evolution as well as celebrating the meeting of art and nature.
The Phyletisches Museum Jena was set up using donated funds; the foundation stone was laid on Johann Wolfgang von Goethe’s birthday on August 28, 1907. On July 30, 1908, Haeckel consigned the building to the Friedrich-Schiller University on the university’s 350th anniversary.
Today the museum forms part of the university’s »Institut für Spezielle Zoologie und Evolutionsbiologie« (Institute of Systematic Zoology and Evolutionary Biology). It accommodates extensive zoological and paleontological collections comprising more than 500,000 specimens. The history of the collections dates back to the 18th century. Some of the most important specimens originate from the period when Goethe (1749–1832) curated the anatomical-zoological collections.

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