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Swamp thing
‘ Ideal conditions ’ reveal London ’ s cannon
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skeletal elements and an outline of its soft-tissue body . Because shark skeletons are made of cartilage , they do not fossilize well , typically leaving archaeologists only teeth and few skeletal fragments . But evidence suggests the fossils , from Nuevo León in Mexico , ended up in swampy conditions that would have allowed for an oxygen-deficient zone , resulting in the preservation of the soft skeletons .
A fossil of the ancient shark
Ptychodus , with almost all skeletal elements
PHOTO : DR JÜRGEN KRIWET
Swamp thing
The mysterious life an of an ancient shark is being revealed thanks to an unusually complete shark fossil . The find indicates where the genus , known as Ptychodus , sat on the shark evolutionary tree , and other previously unknown traits of the enigmatic group of sharks , according to a study published in April . The sharks were notable for their large , rounded rows of teeth , most likely used to crush shelled animals .
The fossil shows almost all the shark ’ s
‘ Ideal conditions ’ reveal London ’ s cannon
A bronze cannon from one of England ’ s most important protected shipwrecks - the 17th century warship , The London , has been revealed on the seabed in the Thames Estuary . The discovery was made by one of Historic England ’ s licensed divers after
The cannon ’ s cascabel on The London Wreck , June 2024
48 being hidden in thick clay and silt for nearly 360 years .
Steve Ellis , Licensee for the London wreck , who has been diving at the site for 14 years , believes very rare ‘ ideal ’ underwater conditions came together to reveal the
PHOTOS : HISTORIC ENGLAND exceptionally well-preserved cannon . The cannon is now being included in Historic England ’ s forensic marking programme , using the latest underwater protective marking technology to deter thieves .
It is believed to be a Commonwealth medium-sized 8 ’ x6 ” Demi-cannon , cast by George Browne 1656 -1657 . At the time of its sinking , the London was one of only four English naval ships to have a full complement of 76 bronze cannons . Each gun carriage would have been unique , because the London ’ s guns originated from different countries and different periods in naval history .
Licensed divers play a vital role in monitoring the condition and recording artefacts of England ’ s most historic and archaeologically significant Protected Wreck Sites . Historic England grants the licences on behalf of the Secretary of State for Culture , Media and Sport .