Fossil evidence of Londons past environments This set

Fossil evidence of London’s past environments • This set of slides introduces some of the different types fossils that have been found in rocks and deposits in the London area. • From the fossils, we can learn more about what the past environment was like and what types of plants and animals were present at different times in the past.

What are fossils? • Fossils are the remains of organisms preserved in rocks or superficial deposits (sediments overlying bedrock) • Fossils can be the whole organism (or part of it), but over time the substance of the organism is changed. Soft tissues rarely survive, whereas hard parts (such as shells, bones, and teeth) are more often preserved. • Fossils can also be the impressions or traces of an organism that lived in the past (e. g. burrows, trails, or footprints) • Scientists who study fossils are ‘palaeontologists’

Fossils in the chalk under and around London • • Chalk is mostly made up of microscopic shells of marine phytoplankton (a type of floating algae called coccolithophores that are abundant in the world’s oceans today) but larger marine organisms are also fossilized in the chalk. You can learn more about chalk fossils here: http: //www. discoveringfossils. co. uk/chalk_formation_fossils. htm Fossil sea urchin (many types still exist today) http: //en. wikipedia. org/wiki/Chalk_Group#m ediaviewer/File: Fossil_Echinoid_Echinocorys. jpg (Dlloyd) A living sea urchin http: //en. wikipedia. org/wiki/Sea_urc hin#mediaviewer/File: Riccio_Melone _a_Capo_Caccia_adventurediving. it. j pg (Marco Busdraghi)

Ammonite fossils have been found in the chalk • Ammonites are an extinct marine animal. • The photo on the left is of a fossil from a Jurassic aged rock in Dorset (but other types of ammonite fossils have been found in chalk). • The image on the right is an artist’s reconstruction of what it may have looked like when alive. http: //commons. wikimedia. org/wiki/File: Ammoni te_Asteroceras. jpg? uselang=en-gb (Dlloyd) http: //en. wikipedia. org/wiki/Ammonite#mediaviewer/File: As teroceras_BW. jpg (Nobu Tamura)

Fossils in the London Clay under and around London • Clay is made up of microscopic plate-like particles that result from the weathering and erosion of rock and are transported by rivers and then deposited in near shore areas of calm water. • Remains of organisms get compacted and preserved in this clay-rich mud. Fossil starfish The shark teeth are from London Clay. The shells are from a much younger deposit called Red Crag found above the London Clay in parts of Suffolk and Essex. http: //en. wikipedia. org/wiki/London_Clay#mediaviewer/File: Ophiura. Wether http: //commons. wikimedia. org/wiki/File: Fossil_finds_at_Walton_on_the _Naze_-_geograph. org. uk_-_1428396. jpg? uselang=en-gb (Derek Voller) elli-Natural. History. Museum-August 23 -08. jpg Captmondo)

Fossils in the London Clay under and around London • The London Clay also contains fossils of plants (such as mangrove trees) that washed into the sea. • From these we know that along the coasts nearby there were lush, tropical forests, similar to those found in Indonesia today. • A famous area for London Clay fossils is the Isle of Sheppey to the east of London. • You can learn more about London Clay fossils (and view more images) here: http: //www. discoveringfossils. co. uk/isle_of_sheppey_fossils. htm

Ice Age fossils in and around London • Over time, ice sheets built up in the Antarctic and Arctic regions, and sea level dropped - the area of London became land. • Many Ice Age fossils have been found in and around London within the deposits of ancient streams.

Ice Age fossils in and around London • There were some brief, warm phases during the Ice Age (interglacials) when the climate in the London area was warmer than today. • During building work in Trafalgar Square, lion and hippopotamus bones were found in silty deposits from an ancient channel of the River Thames which once flowed through the square. • The animals lived about 125, 000 years ago. An image of what Trafalgar Square may have looked like can be seen here. Visit Natural History Museum website http: //www. nhm. ac. uk/aboutus/news/2005/dec/news_7350. html • And here: http: //www. nhm. ac. uk/natureplus/blogs/whatsnew/2014/07/10/londons-wild-times-past-and-present

Ice Age fossils in and around London • There are fossils of animals in the London area that lived during colder phases of the Ice Age (glacials) when the climate was much colder than today. • Examples include mammoths and woolly rhinos (both are now extinct) http: //en. wikipedia. org/wiki/Quaternary_extinction_event#mediaviewer/File: Ice_ag e_fauna_of_northern_Spain_-_Mauricio_Ant%C 3%B 3 n. jpg (Mauricio Anton)