 Ichthyosaurs
Close to the end of the first day of our field-trip, Friday the 28th of February 2003, we are not very satisfied with the results oft the day. On the way back along the cliff Dr. Jens Lehmann suddenly makes a discovery cheering up the whole group: The dark Whitby Mudstone yields a 2cm broad and approximately 4cm long "bar". The finder only discovered it because of the brown colour in contrast to the dark-grey to black plant fossils occuring in these beds.  A hit on the soft claystone, still covering the specimen at that time, exposes the nature of the fossil: The tip of a ichthyosaur snout is laying in the rock just in fromt of us - back to day light after 160 million years. The exquisite preservation of the teeth of an apparently juvenile specimen are tiny and not recognisable for the members of the excursion company before sticking their nose in the mud to see any details.
 The fast rising tide sets a limited time frame to the work of the team. Making every effort the complete block presumably containing remains of the skull has been dug out under dry conditions. However, we assumed that there are more bones preserved than the skull dug out already. The neighbouring rock has to be investigated on the next day because of the rising water level. Saturday, 29th of February: The high tide of the previous night did a good job. A number of lose boulders have been removed by the power of the sea and turned the whole picture of the whole locality, making it very difficult to recognise the spot of the day before. Looking for the right spot preparator Martin Krogmann suddenly discovers the bones of a further ichthyosaur in the rock. This specimen is very well preserved as well. It is a single and isolated, but huge vertebrae of an animal surely several meters in length that is sticking in the Whitby Mudstone.
 We decided to make a small excavation, to reveal the vertebrae and to systematically chisel a rectangle around the valuable find. This large-format method was worth it very much, the slab split just a few millimeters below the base of the vertebrae and traces already its shape.Shortly after this the excavation site of the day before is discovered again, only 5m away from the vertebrae finding! The very paper-thin mud coverage on the rocks behind the rock with the skull remains of the first day has been washed off by the high tide, revealing already further bones in cross section. "With the feet deep in the mud, but with the head in the sky" the excavation is getting through the next round. It is foreshadowing that it will become a fantastic specimen.
 Very slow, millimeter after millimeter, we chisels into the tough dark claystone. Even the very strong hits by a 2.5kg sledge hammer have been buffered too strongly to break into large rock slabs. The only method is chiseling ridges on a large-format into the rock. The aim is to work on predetermined breaking points to wedge off the slabs. After five hours of work the excavation team is completely exhausted, but all of the bone bearing rock fragments have been recovered.
 The slabs are marked by a permanent felt tip pen accurately not to encounter problems to stick together the pieces of the rock puzzle later in the laboratory. Particularly fragile parts of the slabs are fixed by super glue right in the field. Masking tape is used to protect the edges of the broken slabs especially those that reveal already bone fragments in cross section. The way back onto the top of the cliff that is more than 100m high is breath taking and only possible with the joint power of all participants.
The staff of the Geosciences Collection to remain at the helm to carry a particularly heavy "whopper", a slab with bone remains by themselves to the van.
 
What are ichthyosaurs?
Ichthyosaurs were the largest of all inhabitants of the Liassic sea. The longest known specimens that have been found are more than 10m in length, isolated bones indicate that ichthyosaur giants existed with a body length of up to 20m. Like whales ichthyosaurs originate from land-living animals, perfectly adapted to live in the sea by their streamline shape. Contrary to the ancestors of whales ichthyosaurs did not evolve from mammals, that are of minor importance during the Mesozoic, but originated from terrestrial reptiles. The propulsion in the sea water mainly was realised by lateral movements of the caudal fin that shows bones only in their basal part. The dorsal fin helped the animal to stear, the front and hind limbs have been modified to fin-like paddles. The skull was been prolonged like in recent dolphins, with big eyes as clarified by their bony eye ring that has been preserved as fossils. The construction of the skeleton can be seen in a figure that has been drawn by the Geosciences Collection for a specimen of an ichthyosaur housed by the Hanse Wissenschaftskolleg in Delmenhorst.
The stomach content of the ichthyosaurs is rarely preserved, but if present can tell us something about the diet ichthyosaurs ate with their up to 200 pointed, cone-shaped teeth. Their meal consisted of squids (mainly belemnites) and fishes. Ichthyosaurs were too perfectly adapted to life in the sea to get their young on the continent. Actually, there are fossils telling us about their habit to give birth to their young in the sea.
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