Evolution Flashcards
What is Darwin’s theory of evolution?
Natural selection
What does natural selection state?
All species of living things have evolved from simple life forms that first developed more than 3 billion years ago
Darwin’s theory was only gradually accepted because… 3
It challenged the idea that God made all animals and plants that live on Earth, there was insufficient evidence at the time the theory was published to convince many scientists, the mechanism of inheritance and variation was not known until 50 years after the theory was published
What were other theories, like Lamarck’s, mainly based on?
The idea that changes occur in an organism during its lifetime can be inherited
What do we now know about the type of inheritance that Lamarck thought of?
In the vast majority of cases that type of inheritance can’t occur
How do we classify organisms?
By studying the similarities and differences between organisms
Which 3 groups do living things get classified into?
Animals, plants, microorganisms
What 2 things does classifying organisms allow us to do?
Suggest relationships between organisms, help us understand evolutionary and ecological relationships
How does evolution occur?
Via natural selection
What’s the first stage of natural selection?
Individual organisms within a particular species may show a wide range of variation because of differences in their genes
What’s the second stage of natural selection?
Individuals with characteristics most suited to the environment are most likely to survive and breed successfully
What’s the third stage of natural selection?
The genes that have enabled these individuals to survive are then passed on to the next generation
Where new forms of a gene result from mutation, there may be relatively…
Rapid change in a species if the environment changes
