Extinction and Speciation Flashcards
What is extinction?
When an organism can’t evolve quickly enough
Why do species become extinct?
- New diseases kill them
- New predator kills them
- Environment changes too quickly
- Catastrophic event happens that kills them
- They can’t compete with another species for food
What is speciation?
Development of a new species
What is a species?
A group of similar organisms that can reproduce to give fertile offspring
When does speciation occur ?
When populations of the same species become so different that they can no longer breed together to produce fertile offspring
What leads speciation?
Isolation and Natural selection
What is isolation?
Populations of species are separated this can happen due to a physical barrier so e.g. floods and earthquakes , also then conditions on either side of the barrier will be slightly different e.g. different climates
What is natural selection?
When organisms become more better adapted to their environment have a better chance of survival and so are more likely to breed successfully so the alleles are passed on to the next generation
