B1.8 Evolution Flashcards
Explain ‘creationism’
All life created by God
Species created in same form as they are now
Species do not change through time
What is Lamark’s theory?
Species could evolve
Change happened during a lifetime
Acquired changes passed on to offspring
What is Darwin’s theory?
Adaptions are to help organisms survive in their surroundings
Had evolved from single species
Variation in population
Individuals best-suited are more likely to survive and pass on their features
Evolution through natural selection
What were the difficulties with Darwin’s theory?
Challenged belief that God created all life on Earth
Scientists said there was not enough evidence
No way to explain how variety and evolution happened
What is natural selection?
The process by which evolution takes place.
Explain natural selection
The organisms best suited to survive in their habitat are more likely to survive and reproduce (and pass on genes) Those who are best adapted will increase the frequency of genes for that characteristic.
What are the stages of natural selection/evolution?
Mutation Variation Advantage/Adaptation Survival Reproduction Inheritance
What is an example of where a mutation was important when the environment changed?
MYXOMATOSIS (in rabbits)
>Killed most of the rabbits in the UK
>The survivors had a mutated gene
>The survived and bred
What is a recent example of natural selection?
Peppered Moths
>Industrial revolution led to airborne pollution that settled on the trees
>Lighter moths stood out and were reduced by predators
>More dark moths survived
>As pollution levels became better the lighter moths increased again
What is classification?
Organisation of living things according to their similarities.
Why is it hard to find early evolutionary evidence?
The fossil record is incomplete.
Early life forms were soft bodied - little or no fossil evidence.
Fossilization needs certain conditions. some of the fossils have been broken down by geological activities.
