A Journey to the Mesozoic at the Senckenberg Nature Museum, Frankfurt

The Senckenberg Nature Museum Frankfurt ranks among the most important European natural science museums. With its rare and spectacular exhibits, it conveys the current diversity of life as well as the evolution of organisms and thus our earth’s transformation over millions of years. Since the dinosaurs lived more than 66 million years ago, all that remains of them today are fossils. Over millions of years, mineral deposits turned their bones into stone. Fossilized dinosaur bones are not common, and complete skeletons are found very rarely.

Dr. Johann Christian Senckenberg was a physician from Frankfurt. In 1763, he donated his fortune for the construction of a citizens’ hospital that allowed even the poor access to medical care. In his honor, the museum and the Senckenberg Gesellschaft für Naturforschung bear his name.

The Nature Museum in Frankfurt is owned and managed by the Senckenberg Gesellschaft für Naturforschung, which also displays nature’s treasures in two additional museums. But there is much more: it is one of the most important geological and biological research institutions, with worldwide research projects.

Dinosaurs are terrestrial reptiles and populated the earth during the Mesozoic era, approximately 252 - 66 million years ago. But not all of the prehistoric giants occurred at the same time. The Mesozoic is subdivided into three periods, during which different species lived and became extinct: The Triassic (252 - 201 million years ago), the Jurassic (201 - 145 million years ago) and the Cretaceous (145 to 66 million years ago). Besides the terrestrial dinosaurs, pterosaurs and marine reptiles also occurred during the Mesozoic.

While dinosaurs populated the mainland, pterosaurs such as Quetzalcoatlus northropi ruled the airspace. These flying reptiles lived during the late Cretaceous, about 70 million years ago. With a wingspan of approximately 11 meters, Quetzalcoatlus probably glided low over the ocean to hunt fish.

While during the Mesozoic dinosaurs populated the mainland and pterosaurs the air, life under water was ruled by the marine reptiles. Like all reptiles, they also breathed through lungs and had to occasionally come to the surface to breath. In the ocean, there is a higher probability of fossil formation than on land. The dead animals are more quickly covered with sand or mud, and with a lack of oxygen at the ocean floor, even parts of the skin could become fossilized.

This 182-million-year-old ichthyosaur shows an excellent state of preservation. Due to the lack of oxygen and currents at the ocean bottom, the skeleton did not fall apart and we can even recognize the shape of the body: a so-called skin shadow reveals the petrified skin.

The marine reptiles of the Mesozoic constitute the descendants of various reptiles that formerly dwelt on land. Changes in their body shape from generation to generation eventually allowed them to assume an entirely aquatic lifestyle in the ocean. Relatives of these marine reptiles survive until today. For example, the skulls of the mosasaurs are very similar to those of the modern-day monitors.

This mosasaur, Tylosaurus proriger, lived about 85 million years ago during the late Cretaceous. With its large, pointy teeth it ate ammonites and fishes. Mosasaurs could reach a length of up to 10 meters and moved in a snakelike fashion through the water.

Scientists postulate that today’s living birds are the direct descendants of small, two-legged and carnivorous dinosaurs. This means that, strictly speaking, not all dinosaurs became extinct 66 million years ago but survived in the form of today’s avifauna. Thus, we can regard birds as feathered dinosaurs, and it is safe to assume that all of us have actually seen a real, living dinosaur at one time or another.

With a height of 2.75 meters and a weight of up to 150 kilograms, the African Ostrich (Struthio camelus) is the largest living bird and therefore also the largest living dinosaur. The flightless bird is able to run at speeds of up to 70 km/h.