B1.8 - Evolution Flashcards
What was proposed by Darwin in his theory of evolution by natural selection?
Darwin proposed that all species have evolved from simpler life forms than first developed more than three billion years ago.
State three reasons why Darwin’s theory of evolution by natural selection was only slowly accepted.
Darwin challenged established religious beliefs about God creating all life.
There was no knowledge about how genetics worked.
Darwin could not explain why or how the individual organisms had new characteristics and how they passed these on.
What was Lamarck’s theory on how organisms evolve? Why was this wrong?
Lamarck proposed that when an organism used a feature that feature develops. This developed feature is passed onto the offspring. We know that this is not possible in most cases of inheritance.
Genetics supported Darwin’s theory instead.
How can the similarities and differences between organisms give us clues about their evolutionary links?
Organisms that have similar features are likely to be evolutionary related. (E.G - humans and monkeys)
Describe how evolution by natural selection takes place.
Organisms within a species show a genetic variation.
If an organism has an advantageous feature, it is more likely to survive and reproduce.
The genes which confer the beneficial feature are passed onto the next generation.
What can cause rapid changes in a species?
When mutations produce a new form of a gene, a species can rapidly change if the environment changes.
What is likely to happen to an individual that is poorly suited to its environment?
An individual that is poorly suited to its environment will not survive to reproduce.
Why are white peppered moths likely to be more common than black ones in country areas?
White peppered moths are likely to be more common than black ones in country areas because they are more difficult for birds to see on clean birch bark.
