‘Fossil-hunting’ often brings to mind remote locations filled with rocks, sparse vegetation and a bright, merciless sun.
But Dick Mol–an internationally renowned paleontologist–is part of a team that regularly uncovers fossils in an unusual place: the ocean.
His expeditions take place upon the North Sea, a large expanse of ocean between the East coast of the United Kingdom and the coasts of several other European countries such as the Netherlands, Belgium, and Germany up through to Norway.
“The North Sea is very rich,” wrote Dick Mol in an email. “Ever since 1874, fishermen have brought large quantities of bones and molars ashore.”
He himself has written articles about these finds, describing how the area is routinely dredged, enabling large ships passage on this navigational route. This dredging is what helps uncover fossils deposited there so many thousands of years ago. Coupled with trawling—a method of fishing that pulls weighted nets along the sea floor—these fossils are then brought to the surface.
“I learned about the Ice Age mammal remains, trawled by fishermen,” he explained, “from the curator of the Geological and Mineralogical Museum in Leiden, now the NCB Naturalis (Netherlands Center for Biodiversity). At that time, the attic of the museum was full of large bones of trawled mammoth bones, skulls and lower jaws. It was very impressive.”
“I remember,” he continued, “that in November 1992 I brought the late Dr. Andrei Sher, a renowned mammoth expert from Moscow, to the museum. When he entered the large attic, he didn’t believe what he was seeing: perhaps one of the largest collections of isolated mammoth bones in the world. This was recorded by a film crew making a documentary on mammoths in the Netherlands. Once in a while, I rewatch this brief documentary again, and it gives me very good memories of a longtime ago.”
“When he entered the large attic, he didn’t believe what he was seeing: perhaps one of the largest collections of isolated mammoth bones in the world.” — Dick Mol, describing the reaction of Dr. Andrei Sher to a collection of mammoth fossils from the North Sea at the NCB Naturalis in the Netherlands
Known to the world as Dick Mol, his name is actually Dirk Jan Mol, and he has been researching mammoths and other Pleistocene fauna for decades. One cannot study mammoths without becoming acquainted with his name and his work.
In response to what prompted his career in mammoths, he wrote, “I grew up on the border with Germany. Around the town of Winterswijk a lot of different geological sediments and fossils can be found from the Triassic, Cretaceous, Oligocene, Miocene, Pliocene and Holocene eras. In different quarries and clay-pits you could collect fossils, but none were of mammoths or remains of other Ice Age creatures.”
“I have been, since 1968, fascinated by mammoths. In the literature, you could read that these prehistoric animals stood up to 5 meters at shoulder (which was exaggerated, of course). I wanted to know more about mammoths and their ancestors. I wanted to find my own mammoths, but it seems that the mammoth has found me!”
“I wanted to find my own mammoths, but it seems that the mammoth has found me!” — Dick Mol
His enthusiasm for the topic has lead him to become a visiting scientist in 1990 and 1994 at the Mammoth Site in Hot Springs, South Dakota—part of the “Visiting Scholar” program designed by Dr. Larry Agenbroad. He has co-authored numerous papers over the years, and his books include Mammoths (published 1993) and, more recently, Mammoths and Mastodons of the Haute-Loire (published 2010), a bilingual book he co-authored with French paleontologist, Frédéric Lacombat.
Scientists and explorers from all over the world have invited him to help excavate their discoveries: some of the most notable finds include the Jarkov woolly mammoth in Russia (Mammuthus primigenius), the Nolhac steppe mammoth in France (Mammuthus trogontherii), and parts of a mastodon skeleton in Greece (Mammut borsoni), in which the longest tusks found to-date were uncovered (502 cm in length).
Queen Beatrix of the Netherlands knighted him for his work in paleontology in 2000. In addition, he is President of Mammuthus Club International and has been involved in the international conference related to mammoth research for years.
His family’s personal collection of fossils exceeds 30,000 specimens that have been used for educational purposes and scientific studies.
Today, he is a Research Associate at the following institutions:
- Natural History Museum Rotterdam, the Netherlands
- Natural History Museum, Milia, Greece
- Historical paleontological collections, Siatista, Greece
For all of his accolades and accomplishments, Dick Mol is a very accessible and kind man. One witnesses his infectious enthusiasm in these two videos about his work in the North Sea:
Trawling for Mammoths: http://www.bbc.co.uk/programmes/p01q0gfr
A Mammoth Task: http://www.bbc.co.uk/programmes/p01q29mg
“Over the years, tons and tons of bones have been trawled by fishermen in their nets,” he reiterated. “Between 1997 and 2003, we weighed the mammoth bones: 57 tons, not including 8000 mammoth molars (!) of woolly mammoths. The southern bight of the North Sea between the British Islands and the Netherlands is very rich in Pleistocene mammal remains. It is a real treasure trove.”
“Between 1997 and 2003, we weighed the mammoth bones: 57 tons, not including 8000 mammoth molars (!) of woolly mammoths. The southern bight of the North Sea between the British Islands and the Netherlands is very rich in Pleistocene mammal remains. It is a real treasure trove.”–Dick Mol
“In the meantime, I have organized 43 mammoth fishing expeditions on the North Sea using big beam trawlers. Quite spectacular and always a good catch. Doing these expeditions gave us very good insight into those areas that are very productive and those areas in which Pleistocene fossils are scarce.”
Given the enormous number of fossils brought up from dredging, it doesn’t take a lot of imagination to wonder whether there might be exciting fossil discoveries just waiting to be found if one could go even deeper.
“Yes, for sure,” he agreed. “Most of the bones trawled by the fishermen have been washed out of the seabed by currents. The Eurogully area, off the coast of the province of South-Holland, was dredged from 13 to 40 meters below sea level. At approximately 23-26 meters, there is a rich layer with bones and teeth from the Late Pleistocene. Deeper, there is a layer containing an interglacial fauna (110.000-130.000 BP) including Hippopotamusses and straight-tusked elephants. This is true for the entire southern bight of the North Sea.”
Private collector with the femur of the so-called straight-tusked elephant from the North Sea,image courtesy of Hans Wildschut and Dick Mol
But the cost of such an underwater excavation might be prohibitive.
“Once, I used a diver on one of the expeditions. Visibility was very poor, and it was not successful. But some divers in the past have found some mammoth remains. Amongst others, a diver brought up a complete mammoth tusk.”
Aside from the need to desalinate fossils found in the North Sea, they are not physically treated any differently than fossils one finds on land. And despite the wealth of fossils found thus far, Dick Mol does not have any favorites.
“For me,” he wrote, “every bone, bone fragment or remnant is unique and tells us a story….”
Mammoth tibia freshly trawled from the North Sea with fish, image courtesy of Hans Wildschut and Dick Mol
Keep in mind, however, that these fragments and bones are not found together.
Paleontology is like detective work: terrestrial excavations include mapping by grid, pictures, and notes related to where each bone is found. All of these details help paleontologists better understand what species it is and what happened to that animal before and after it died.
The bones found in the North Sea are pulled up individually in a mass of fish and other debris.
Without any of the clues available to someone digging on land, this begs the question: can one determine to which species a bone belongs in isolation?
“[A]fter spending more than 40 years of my life identifying isolated skeletal elements (we have never retrieved a complete skeleton from the North Sea bed) again and again, using comparative collections, it is possible to identify the specimens as soon as they are on the deck of the vessel.”
“Sometimes,” he added, “I need to use literature, but in most cases, an experienced anatomist can do it right away.”
And what about the isolated teeth that have been found in abundance?
“[A]t least three different species of mammoths are well-documented: from the Early Pleistocene the southern mammoth, (Mammuthus meridionalis); from the Middle Pleistocene the steppe mammoth, (Mammuthus trogontherii); and from the Late Pleistocene the woolly mammoth, the icon of the Ice Age, (Mammuthus primigenius). The molars of these species are quite different and easy to tell apart from each other by an experienced specialist.”
Grooves and marks upon the bones give rise to questions about who or what caused them: humans or other Pleistocene animals? And how can one tell the difference?
“Hyena gnawing marks and other predators are well-known and, in general, easy to recognize. Of course, you need some training and experience. Sometimes, especially in large bones, one can see the deep grooves in the so-called material spongiosa caused by hyena (pre)molars. Hyena gnawing marks are very often found in the skeletal remains of woolly mammoths and woolly rhinoceroses. The ice-aged hyena was very common on the Late Pleistocene mammoth steppe environment. Cut marks caused by human activity are completely different from those of predators.”
The “quality and quantity” of the fossils in the North Sea are two things that surprise him the most.
“We have huge collections, and we are constantly learning from them.”
Private fossil collection storage, image courtesy of Hans Wildschut and Dick Mol (Dick Mol is pictured on the left)
Please click on this (or any) image to see it in more detail, image courtesy of Hans Wildschut and Dick Mol; highlighting by author
“Recently, many collectors are also focusing on small mammal remains (micro-mammals like voles and lemmings). These remains can be found on the beaches of the North Sea where Pleistocene sediments have been added to strengthen the coastline. Some collectors have hundreds and hundreds of small molars of the entire small mammal fauna. These small mammal remains provide very interesting data to complete the picture of the woolly mammoth and its Ice Age world. In other words, it gives us a window into the small animal community that coexisted with the megafauna.”
“These small mammal remains provide very interesting data to complete the picture of the woolly mammoth and its Ice Age world. In other words, it gives us a window into the small animal community that coexisted with the megafauna.”–Dick Mol
There are two questions that come to mind regarding the volume of fossils collected so far: where are these fossils stored and how long does it take to catalog and study such collections?
“It is a continuous process,” he stated, referring to the length of time needed to catalog and study the fossils.
But in terms of where they are stored, he wrote, “[t]he NCB Naturalis (Netherlands Center of Biodiversity Naturalis in Leiden) has a huge collection of fossil bones from both the North Sea, as well as from dredging operations in the floodplain of our rivers like Rhine, Meuse and IJssel. Really, a huge collection.”
“Using about 200 skeletal elements of mammoths of almost the same size, same age and same gender, we compiled a skeleton for museum display, a huge male individual. Another extensive collection is housed at the Natural History Museum in Rotterdam. Here, a huge collection of Pliocene and Pleistocene marine mammals is stored. Most of these marine mammal remains have been trawled from the seabed as well, and some of these animals coexisted together with terrestrial mammals like mammoths and other large animals. The marine mammals were living in the paleodeltas.”
Woolly mammoth skeleton at the NCB Naturalis Leiden Museum, the Netherlands, composed of individual fossils found within the North Sea, image courtesy of Hans Wildschut and Dick Mol
“And there are some private collections. Some of them are very well documented. They are like professional collections, and they are available and often used for scientific studies.”
“The co-operation between non-professional and professional paleontologists is extremely good in the Netherlands. For more than three decades, both groups have been working closely together on mammoths and mammoth fauna, scoring very interesting results like 14C, stabile isotopes, new species, etc.”
Dick Mol himself posed the final question: “What can we learn from the mammoth bones trawled from the North Sea between the British Islands and the Netherlands?”
“The rich terrestrial mammal remains trawled teach us that the North Sea between Britain and the Netherlands was once dry land,” he explained. “The British Islands were connected with the mainland of Europe during the entire Pleistocene or Ice Age (2.580.000 – 11.500 BP). That area was inhabited by different faunas.”
“In the Early Pleistocene, it was a savannah-like environment, dominated by the southern or ancestral mammoths, (Mammuthus meridionalis). In the Middle Pleistocene, it was a steppe-like environment dominated by the steppe mammoth, (Mammuthus trogontherii), and in the Late Pleistocene, it was a cold, dry and almost treeless steppe dominated by woolly mammoths, (Mammuthus primigenius).”
Woolly mammoth skeleton at the Hellevoetsluis Museum, the Netherlands, composed of individual fossils found within the North Sea, image courtesy of Hans Wildschut and Dick Mol
“At the end of the Pleistocene, this landscape disappeared, caused by dramatic change of climate. It became warmer and warmer, and ice–which blanketed the northern hemisphere–started to melt. Melted water filled up lower countries, and the vast plain became ocean. We know this area today as the ‘North Sea’, and it reached its present sea level about 8,000 years ago. The mammoth steppe disappeared and the mammoth fauna became extinct. This extinction is what we need to accept; it is not dramatic.”
“These events—of which we can learn from the North Sea fossils–show us that we are on a living planet and extinction belongs to it.”
A Mammuthus trogontherii-sized THANK YOU to Dick Mol for his generous and detailed answers to my many, many questions; for his time, his wisdom and his thoughtfulness! What a truly great honor and a great pleasure!!
Dick Mol, image courtesy of Hans Wildschut and Dick Mol
Dick Mol’s papers and research: http://hetnatuurhistorisch.academia.edu/DickMol
The Eurogeul—first report of the palaeontological, palynological and archaeological investigations of this part of the North Sea: http://www.sciencedirect.com/science/article/pii/S1040618205000649
For fascinating pictures and in-depth descriptions of mastodons and mammoths, Mammoths and Mastodons of the Haute-Loire is a great book (published 2010, in English and in French): http://www.amazon.fr/Mammouths-Mastodontes-Haute-Loire-Dick-Mol/dp/2911794974/
If you are interested in seeing more of Hans Wildschut’s exciting work, here are links provided by Dick Mol:
Trawling and fossils:
Remie Bakker and the creation of the life-sized model of the Mastodon of Auvergne: