C - Evolution Flashcards
What is evolution?
Where all life on earth began as simple organisms from which all the more complex organisms evolved
What do evolutionary relationships show us?
How things are related
What do ecological relationships show us?
How things interact with eachother
What do evolutionary trees show us?
Common ancestors and relationships, the more recent the ancestor, the more closely related the two species are.
If we see organisms in the same environment with similar characteristics, it suggests they might be in…
Competition
What is natural selection?
- Individuals show variation because of the differences in their genes
- Individuals with characteristics that make them better adapted to the environment have a better change of survival and breed more successfully
- Therefore the better characteristics are passed on in the next generation
What is a mutation?
A change in an organisms DNA
Most of the time mutations have no effect, but occasionally they can be ________ by producing a useful __________. It may give them a better chance of surviving.
Beneficial
Characteristic
Who was the inventor of natural selection?
Charles Darwin
Why was Darwins theory very controversial at the time? (3) name 2
- It went against religious beliefs - there was then not a creator (God)
- He didn’t have a good explanation why these new characteristics appeared because he didn’t know about genes or mutations
- There wasn’t enough evidence to convince many scientists, bcos not many studies had been done before
What was Lamarck’s theory of evolution?
That if the characteristic of an organism was used a lot then it would become more developed over its lifetime and pass the better characteristics onto the next generation e.g. A rabbit who used its legs to run a lot, gave its longer legs to its offspring
The only way to find out whose hypothesis is right is to….
Find evidence to support or disprove each one
Who’s theory was correct? Darwins or Lamarck?
Darwins - it now has an accepted hypothesis
