Field of Science

History of Paleomammology: From ancient times to mass extinctions

Today dinosaurs are popular and almost everywhere to be found, somehow like the fantastic dragons on ancient maps, and they also get a (to) very prominent media coverage. But until Victorian time people were interested in another fossil groups - especially the paleomammals. The last century brought also important discoveries on these animals, so it's a little shame that the palaeontology of this group is often neglected in the general public.

It seems almost certain that fossil mammals were first noticed and interpreted in ancient mythology; one example of how myths incorporated fossil remains is given by the depiction on a Greek vase of Hercules fighting the monstrous Ceto. Some authors, like the American Adrienne Mayor, argue that the representation was inspired by the discovery of skulls emerging from sediments.


Giant bones were intensively collected during the medieval period in Europe, and then displayed on public places like churches (where sometimes they can still be found today) or incorporated in private collections - especially in France, Germany, Austria, Switzerland and Italy.
The unconsolidated sediments of the Ice Ages, outcropping mostly everywhere and easy to dig, often contained bones of mammoth, woolly rhinoceros and other large and extinct animals of the Pleistocene tundra.
However, the true nature of these findings remained uncertain, proposed explanations range from remains of mythical beings such as dragons, giants and unicorns, to victims of the global food of Noah, to simple inanimate forms generated spontaneously by the earth itself.

Until the 17th century the opinions if the fossils represent bones of living things differed from author to author - one reason was the surprisingly limited anatomical knowledge at these times, even considering common animals such as domestic horses and cattle.

In the 18th century scientific progress makes it obvious that the fossil bones can be compared with bones of modern animals - which raise even more questions. Many identified fossils belong to animals unknown in Europe, but if so, are they still alive, maybe on other continents or in other climatic zones?
Thomas Molyneux, an Irish priest, in 1697 assumes in his " A Discourse Concerning the Large Horns Frequently Found under Ground in Ireland...[]" that the giant antlers found in the soil of Ireland are related to the North American elk, extinct locally in Ireland due human hunting, but still alive in other parts of the world. Instead the antlers belong, as we now know, to Megaloceros, a giant, but anyway extinct deer species.


Fig.1. Depiction of Megaloceros skull, from MOLYNEUX 1695.

But at these times the complete extinction of a species - perfectly created by God- still seems unthinkable.

Only after 1768, with the discoveries of bones in America and the identification of these bones by the English naturalist Collinson as belonging to an unknown species of the order proboscidea, the possibility that the remains represent extinct animals becomes more and more convincing.
With more and more fossils, more and more evidence is available, and especially thanks to the arguments of the French naturalist Georges Cuvier (1769-1832) from 1800 onwards the extinctions of species is accepted as a scientific fact.

The French naturalist Georges-Louis Leclerc, Comte de Buffon (1707-1788) studies carefully the known living and fossil vertebrates, and based on his observations, in 1717 he publishes "Les Epoques de la Nature". In this publication he proposes to divide the age of the earth - that he assumes in astonishing 75,000 years - in seven periods, distinguished by their characteristic faunas, implying that animals unsuited to new circumstances have become extinct in large and periodic mass extinctions.

Extinctions are caused by geological and climatic changes, in Europe for example the differences in the paleontological record can be explained only by the effects of a sudden cooling event. "It's impossible", he resumes, "to transform an elephant in a reindeer."


His affirmations arouse great resistance by theologians of the University of the Sorbonne, and only his close friendship with the King protected him from retaliations. But thanks' of Buffons literary style (he can be considered the Carl Sagan of these times) his ideas spread quickly throughout the naturalists community and also the general public. His later work "Histoire Naturelle", published between 1749 until 1788 and dealing with the natural history of quadrupeds, is the most read book of his time.


References:

BENTON, M.J.; COOK, E. & HOOKER, J.J. (2005): Mesozoic and Tertiary Fossil Mammals and Birds of Great Britain. Geological Conservation Review Series 32: 215

BUFFON Conte de, G.-L.L. (1781): Epochen der Natur übersetzt aus dem Französischen. Zweiter Band.

BUFFON Conte de, G.-L.L. (1749-1788): Histoire naturelle. 36 Volumes. Imprimerie royale

MOLYNEUX, T. (1695): A Discourse Concerning the Large Horns Frequently Found under Ground in Ireland, Concluding from Them That the Great American Deer, Call'd a Moose, Was Formerly Common in That Island: With Remarks on Some Other Things Natural to That Country. Philosophical Transactions 19 :489-512

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