Active learning ideas
This topic explores the fossil record, the primary evidence for the evolution of life on Earth. Students investigate the specific conditions required for fossilisation, such as rapid burial and the presence of hard parts. They focus on the morphology and evolutionary trends of key British fossil groups, including trilobites, ammonites, and graptolites, and learn why these are excellent 'zone fossils' for correlating rock layers across different regions.
Activity 01
Set up stations with different fossil groups (Brachiopods, Corals, Echinoids). Students use checklists to identify key features (e.g., symmetry, growth lines) and sketch them, then use a key to determine the fossil's likely lifestyle, sessile, planktonic, or nektonic.
What conditions are necessary for fossilisation?
Activity 02
Pairs are given 'borehole' logs from different parts of the UK containing various fossils. They must use 'zone fossils' to match up the layers and determine which rocks are the same age, even if the rock types are different.
How are zone fossils used to correlate rock layers?
Activity 03
Students read a brief account of Mary Anning's discoveries in Lyme Regis and the challenges she faced as a woman in 19th-century science. They discuss in pairs how her work changed our understanding of 'deep time' and share their thoughts with the class.
What evolutionary trends are visible in trilobites?
A few notes on teaching this unit
Watch Out for These Misconceptions
Fossils are actual bones or shells.
Most fossils are 'petrified', meaning the original organic material has been replaced by minerals like silica or calcite. Hands-on comparison of a modern shell and a fossilised one (noting the weight difference) helps students understand the process of permineralisation.
Evolution is a straight line of 'improvement'.
Evolution is a branching process of adaptation to changing environments. Examining trilobite diversity over time helps students see that many successful groups eventually go extinct when their environment changes too rapidly.
Methods used in this brief
Principles of Stratigraphy and Geological Time
Pupils will apply the principles of superposition, cross-cutting relationships, and unconformities to determine relative geological ages. They will also learn about absolute dating methods.
8 methodologies
Mass Extinctions and Climate Change in the Geological Past
Pupils will investigate the causes and evidence of major mass extinction events, such as the K-Pg boundary. They will also explore how geological evidence records past climate changes.
8 methodologies