Sunday 26 December 2021

AWKWARD AND AWESOME: DIMORPHODON

This remarkable fellow is Dimorphodon — a genus of medium-sized pterosaur from the Early Jurassic. He is another favourite of mine for his charming awkwardness.

You can see this fellow's interesting teeth within his big, bulky skull. Dimorphodon had two distinct types of teeth in their jaws — an oddity amongst reptiles — and also proportionally short wings for their overall size. 

Just look at him. What an amazing beast. We understand their anatomy quite well today, but can you imagine being the first to study their fossils and try to make sense of them. 

The first fossil remains now attributed to Dimorphodon were found in England by fossil collector Mary Anning, at Lyme Regis in Dorset, the United Kingdom in December 1828. While she faced many challenges in her life, she was blessed to live in one of the richest areas in Britain for finding fossils. 

She walked the beaches way back in the early 1800s of what would become the Jurassic Coast UNESCO World Heritage Site. The Jurassic Coast holds some of the most interesting fossils ever found — particularly within the strata of the Blue Lias which date back to the Hettangian-Sinemurian. It is one of the world’s most famous fossil sites. Millions come to explore the eroding coastline looking for treasures that provide delight and inspiration to young and old.

These fossil treasures provide us with tremendous insights into our world 185 million years ago when amazing animals like Dimorphodon ruled the skies. 

Mary's specimen was acquired by William Buckland and reported in a meeting of the Geological Society on 5 February 1829. Six years later, in 1835, William Clift and William John Broderip built upon the work by Buckland to publish in the Transactions of the Geological Society, describing and naming the fossil as a new species. 

As was the case with most early pterosaur finds, Buckland classified the remains in the genus Pterodactylus, coining the new species Pterodactylus macronyx. The specific name is derived from Greek makros, "large" and onyx, "claw", in reference to the large claws of the hand. The specimen, presently NHMUK PV R 1034, consisted of a partial and disarticulated skeleton on a slab — notably lacking the skull. Buckland in 1835 also assigned a piece of the jaw from the collection of Elizabeth Philpot to P. macronyx

Later, the many putative species assigned to Pterodactylus had become so anatomically diverse that they began to be broken into separate genera.

In 1858, Richard Owen reported finding two new specimens, NHMUK PV OR 41212 and NHMUK PV R 1035, again partial skeletons but this time including the skulls. Having found the skull to be very different from that of Pterodactylus, Owen assigned Pterodactylus macronyx its own genus, which he named Dimorphodon

His first report contained no description and the name remained a nomen nudum. In 1859, however, a subsequent publication by Owen provided a description. After several studies highlighting aspects of Dimorphodon's anatomy, Owen finally made NHMUK PV R 1034 the holotype in 1874  — 185 million years after cruising our skies the Dimorphodon had finally fully arrived.