Having had the opportunity to work as a teacher, helping young people to learn more about Earth sciences through their fascination with dinosaurs and other prehistoric animals, I am constantly amazed at how quickly children learn dinosaur facts and the names of other creatures from the fossil record. Children as young as three seem to have a capacity to absorb dinosaur trivia and have been known to trip me up from time to time with their questions. Yet, still I encounter some children and indeed, their parents who seem to think that all extinct ancient reptiles from the past must have been dinosaurs. This is far from the truth, the Order Dinosauria only represents a fraction of the vertebrate fossils known, and a relatively small proportion of the reptile fossils. One frequent misconception is that the Pterosaurs, otherwise known as the flying reptiles were dinosaurs, this is not the case and I do my best to explain this in the course of my teaching. My favourite Pterosaur genus is that of Rhamphorhynchus and I use illustrations and information about this particular Jurassic flying reptile to illustrate the differences between it and the Dinosauria.
My Favourite Pterosaur - Rhamphorhynchus
Fossils of Rhamphorynchus have been studied by academics for nearly two hundred years. Fossils of these late Jurassic Pterosaurs have been found in England, Germany, Spain and east Africa (Tanzania). There have also been Pterosaur teeth found in Upper Jurassic sedimentary strata in Portugal, these have been tentatively ascribed to the Rhamphorhynchus genus.
As Pterosaurs go, there are certainly far more spectacular forms than the Rhamphorhynchidae. For example, there is the enormous late Cretaceous Pteranodon (Pteranodon longiceps) from the western part of the United States. Pteranodon was one of the largest flying reptiles, with a wingspan of approximately 8 metres and an impressive head crest. Rhamphorhynchus had no head crest, and it was considerably smaller, but for me this long-tailed, flying reptile has always fascinated me and I continue to be keen to learn more about this particular part of the Pterosauria.
Rhamphorhynchus - A Description
Rhamphorhynchus was a member of the Pterosauria, not a dinosaur but a flying reptile, closely related to the dinosaurs but a distinct group. Like the Dinosauria, the Pterosauria were Archosaurs, evolving some time in the mid Triassic and surviving until the end of the Cretaceous period. Rhamphorhynchus (Rhamphorhynchus muensteri) was a Pterosaur of coastal areas and inshore environments that lived at the end of the Jurassic, although fossils ascribing to the Rhamphorhynchidae family cover a period of nearly 30 million years in the stratigraphic record. Like all flying reptiles, the wings were flaps of skin (possibly covered in tiny insulating hairs). These wings stretched from the elongated fourth finger of the hand down to the animal's ankles. Rhamphorhynchus muensteri had a wingspan of approximately 1.5 - 1.8 metres, making it about the size of the UK's largest seagull (the Great Black Headed Gull - Chroicocephalus ridibundus). This is quite appropriate as fossils of this Pterosaur are associated with sedimentary deposits such as marine clays and limestones, laid down in coastal environments such as shallow seas, estuaries and lagoons. The animal had light, hollow bones and even a fully grown adult probably weighed less than six kilogrammes. The teeth in the jaws were long, pointed and needle-like. The teeth interlocked when the jaws were closed, suggesting that this Pterosaur was a hunter of fish and squid. These slippery prey items could have been snapped up in jaws and the interlocking teeth would have held the prey securely.
Rhamphorhynchus, unlike later Pterosaurs had a long, stiff tail, at the end of which was a diamond shaped rudder. The specimens from the Solnhofen lithographic limestones, the same strata from which the famous Archaeopteryx (early bird) fossils were found; are exquisite. As well as the delicate bones, this fine grained limestone has preserved soft tissues, internal organs and even impressions of the wings. Over a hundred Rhamphorhynchus fossils have been excavated from the Solnhofen quarries (Bavaria, Germany). Such a large number of fossils has enabled scientists to examine the growth rates of this flying reptile and to learn how babies and juveniles differed from adults. The research into growth rates indicates that this type of Pterosaur grew at approximately half the rate of later Pterosaur genera.
Reasons for Rhamphorhynchus being a Favourite
When compared to the giants of the Pterosaur world, creatures such as Quetzalcoatlus, for instance, this example of a more primitive, long-tailed flying reptile would hardly rate a mention. However, it is because of the wonderfully preserved Solnhofen fossils that makes Rhamphorhynchus a favourite of mine. There are a lot of models, posters and craft kits available that choose Pteranodon or Quetzalcoatlus as their template, however, one of the very first Pterosaur models I owned came with the Aurora manufactured Jungle Swamp construction kit. This was an American inspired prehistoric animal, snap-together kit series and the Jungle Swamp, permitting young model makers to create their own prehistoric jungle scene was one of the best in the entire range. It featured two Pterosaur models, both were Rhamphorhynchidae, a rare example of these flying reptiles being represented in children's model kits. Perhaps it is because of my memories of building the Aurora Jungle Swamp kit that I have such an affection for Rhamphorhynchus.
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