What is linking collagen, women and Great White sharks?

Women use it to reduce wrinkles, great white shark skin is enveloped in it, and now two scientists have discovered a fish-like marine reptile that lived during the age of dinosaurs used it.

So, what is it? Collagen.

Collagen is in animal bones and connective tissue. A fibrous protein, it helps give skin its elasticity, and when it breaks down wrinkles appear.

Theagarten Lingham-Soliar of the University of KwaZulu-Natal in South Africa and Gerhard Plodowski of the Senckenberg Research Institute in Germany examined fossilized soft-tissue from a well-preserved specimen of an Ichthyosaurs species called Stenopterygius quadricissus.
They found the sea reptile propelled itself with fins reinforced by a fiberglass-like mesh.

In fiberglass, thin strands of glass are mixed with plastic to provide strength. The result is a strong material that can be molded into any shape. Fiberglass is often used in airplanes, cars, and boats.

Research revealed the Ichthyosaurs used collagen to produce the mesh that would have kept their dorsal and tail fins rigid, allowing the creatures to glide through the water like torpedoes.
"Collagen is one of the most effective materials for toughening something, so from that point of view, it's not a surprise," Lingham-Soliar said. "Where one is surprised is to find good soft tissue in an animal that is so, so very old -- 200 million years old -- and to actually find the collagen fibers in the (fin) structures. That becomes near miraculous."

The finding, to be detailed in an upcoming issue of the German science journal Naturwissenschaften, is an example of convergent evolution, in which animals not closely related develop similar characteristics.

Collagen-stiffened fins and a streamlined body shape also evolved in fast-swimming tuna, dolphins and sharks.

Ichthyosaurs first appeared about 250 million years ago, slightly earlier than dinosaurs, and disappeared just before them. They ranged in length from 2 feet to more than 40 feet, but most were around 9 feet long. At their peak during the Jurassic, they were the ocean's top predators.
Ichthyosaurs' body shape suggested it was a fast swimmer, but until now, it was not known what kept their fins rigid. Scientists suspected collagen, but the new study is the first to confirm it.