B5.2.2 - Evidence For Evolution Flashcards
How are fossils formed?
When animal or plant remains are preserved in rocks
Where in the rock is the most recent fossil most likely to be located?
At the top
What is a fossil record?
The sequence in which the fossil layers from to show how they have changed over time
Describe in detail how fossils are formed.
Animal / plant dies.
Flesh rots away, skeleton gets buried under sand and clay
Over millions of years the skeleton becomes mineralised and trapped inside rock
The fossil emerges when rocks shift due to erosion
How would you investigate which species the modern day species evolved from?
Bone structure
Anatomy
What species did the horse evolve from?
Eohippus
How has the eohippus evolved and adapted into the horse?
Eohippus had multi toed hooves which helped it trek in the rainforest while horses have singled toed hooves for grassland
How might fossils be destroyed?
Soft-bodied organisms decompose before fossilising
Volcanic eruptions can destroy fossils
How did the Atlantic tomcod evolve?
It became resistant to PCBs, an industrial waste toxic to most animals
