Evolution Flashcards
What is evolution?
The scientific idea that all species on earth today have adapted over millions of years.
What are the differences between different members of the same species called?
Variations
What are variations?
The differences between different members of the same species
What do variations mean in terms of evolution?
Creatures with more helpful adaptations for their environments are more likely to survive and pass on their genes.
The ancestors of giraffes had shorter necks but today they have longer necks. Why?
The giraffes with shorter necks wouldn’t be able to reach many of the leaves on the trees and would die because there wasn’t enough food. However giraffes with longer necks would be able to reach the food and would be able to pass on their longer necked genes.
What happens if a species environment changes rapidly?
The species may become extinct.
What is peer review?
When scientists review each others work before it gets published in a scientific journal
Why was Darwin’s theory only gradually accepted?
There was not much evidence at the time/not many fossils
Went against the Christian belief that God created the world
What are 3 types of evidence for Darwin’s theory?
Fossils/early tools
Genes/DNA
Animals of the same species share similar characteristics
Define extinction
When all individuals of a species have died
How do we know that dinosaurs existed?
Fossils
What are the 3 theories for the extinction of the dinosaurs?
The super volcano
The asteroid
Climate change
Describe the asteroid theory
A 6 mile wide asteroid landed in the gulf of Mexico making dust rise into the air so it blocked the sunlight. This meant the plants died and then the plant eating dinosaurs died and the entire species became extinct.
Describe the super volcano theory.
In India several super volcanoes erupted over a span of 10,000 years and the ash rose and blocked out the sun so plants couldn’t grow and herbivore dinosaurs died then the entire food chain collapsed.
Describe the climate change theory
Some major event meant that the Earth’s temperature rapidly changed and the dinosaurs couldn’t adapt quickly enough to survive.
