Origins Of Life On Earth and evolution Flashcards
What can we learn from fossils?
How much and how little organisms have changed since life developed on earth.
When do scientists think life on earth began?
Between 3 billion and 4.5 billion years ago
How can fossils be found?
When an animal or plant did not decay after it died
Who was Lamarck and what was his theory?
He was a French biologist who had a theory that every type of animal evolved from primitive worms he thought that the change from worms to other organisms was caused by the inheritance of acquired characteristics.
Why was Lamarck’s theory not accepted?
There was no evidence and people didn’t like the idea of being descended from worms people could quite clearly see that characteristics acquired were not passed on to there children.
What was Charles Darwin’s theory?
It was that all living organisms have evolved from a simpler life forms this evolution has come about by process of natural selection.
What is the evidence for evolution?
Fossil records shows us how species have evolved over millions of years and how different species are related to each other.
What is natural selection?
Survival of the fittest
What is mutation?
When new forms of genes result from changes in existing genes their tiny changes in long strands of DNA.
What is extinction?
The permanent loss of all members of the species from the face of the earth.
How does climate change affect extinction?
Organisms which do well in the heat of tropical climate won’t survive in icy landscapes, many of them therefore become extinct through lack of food or being too cold to breed.
How does climate change affect natural selection?
New spaces which cope well in cold climates evolve and by thrive natural selection.
How can organisms cause extinction?
If I knew predator turns up in an area it can wipe out unsuspecting prey animals very quickly.
New diseases caused by microorganisms can drive a species to the point of extinction.
Also one species can drive to another to extinction through a successful competition.
