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Duck-Billed Platypus Lived Alongside Duck-Billed Dinosaurs

The Duck-Billed Platypus - One of the Oldest Type of Mammals

The Platypus is a bizarre looking Australian mammal, one of the few monotremes left in the world - a mammal that lays eggs. When this strange-looking creature, which can grow up to 50 centimetres long, was first studied by western scientists they thought the bill had been glued or sewn into place, few could believe that this animal was real and many dismissed drawings as total folly or an elaborate hoax. However, this highly specialised freshwater mammal rather than being an oddity might just have remained unchanged for 120 million years. This would make the humble Platypus one of the oldest kinds of mammal on the planet, with its origins now traced back to the middle of the Cretaceous. Animals similar to the duck-billed platypus and ancestral to the species now found in Australia may have shared their environment with dinosaurs, ironically even duck-billed dinosaurs.


A Native of Australia

A native of Australia, the Platypus uses its highly sensitive bill to find shrimps and worms underwater. When a Platypus dives it effectively becomes blind and deaf, the bill replaces these senses by detecting prey, first by touch and then by tiny sensors that can detect the faint electrical charges given off by living organisms. So effective is this device that an adult Platypus can eat up to half its own body weight in a single night. It needs to, as it requires a high calorie intake to maintain its active life style. These animals are secretive and difficult to spot in the wild, most of them hunt at dusk or in the night, so tourists trying to catch a glimpse of one of these "living fossils" would have to be very lucky indeed to spot one.

Very Similar to Reptiles

Scientists have known for some time that as a monotreme it shares a number of characteristics with reptiles. For example, the shoulder bones resemble those found in fossil Therapsid reptiles. Platypus sperm is thread-like, similar to a reptiles rather than being tadpole shaped and of course the Platypus lays eggs, just like a reptile.

However, a fossilised jaw under the study of Dr Tom Rich and his partner Professor Pat Vickers-Rich has been identified as belonging to a member of the Platypus family and as the jaw dates from 120 million years ago, this puts the little Platypus right in amongst the dinosaurs of the Cretaceous period.

Palaeontologists Dr Tom Rich from Museum Victoria and Professor Pat Vickers-Rich from Monash University have been searching the southern coastline of Victoria for the remains of early mammals for more than two decades.

Close Study of Jaw Fragments shows Platypus Ancestry

New analysis of three jaw fragments found ten years ago at Flat Rocks, near Inverloch, Victoria (Australia), has enabled the husband and wife team to positively link the fossils to the Platypus family. Using a high resolution CT scanner in Texas the scientists discovered this ancient animal (named Teinolophos) had a large internal grove or canal along its jaw to help carry nerve fibres from the bill to the brain - just like a modern Platypus. This puts this ancient mammal into the same family as the Platypus, the Ornithorhynchidae.

Dr John Long (Museum of Victoria) commenting on the results of the CT scans stated that when these tiny fossil jaws were first discovered, it was thought that they may have belonged to an ancient ancestor of the modern Platypus, a close relative but not an actual Platypus type creature. After all, the fossil jaws have teeth and the modern Platypus has none.

The recent discoveries made in the last few years have shown with the high resolution CT scanner in Texas that some of these jaws that they found, they are actually in the same family, Ornithorhynchidae, as the modern Platypus and this is absolutely outstanding as it suggests that Platypus-like animals have been living on Earth for a very long time.

Not a Bizarre Animal but a Skilled Survivor

The Platypus far from being some sort of accident of nature has proved itself to be a very capable survivor with the basic body plan remaining unchanged throughout the Age of Mammals. For a large part of the Cenozoic Australia has been cut off from other land masses and this has helped ancient animals such as the Platypus to survive to see the evolution and development of the human race. Ironically, the Platypus still can be found in Victoria, inhabiting streams just a few miles inland from where the ancient fossilised Platypus jaw bones were found.

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Article Source: Mike Walley


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