CB4 - Natural selection and Genetic Modification Flashcards
What is evolution?
The gradual change in the characteristics of a species over time.
What were the names of all the fossils showing human evolution?
Ardi
Lucy
Homo habilis
Homo erectus
Homo sapiens
How did scientists discover human evolution?
Fossils
How did scientists discover human evolution?
Fossils
What were the changes in characteristics in the human fossils?
Facial features got smaller
Brain casing grew in size
How is human evolution seen through the tools used?
The tools got smaller and more refined.
Symbols started getting put on the tools.
How can we tell how old a fossil is?
How deep it is underground
Carbon dating
Why do scientists carbon date the rock around the tool and not the tool?
The stone or materials used to make the tool are older than the tool itself.
What is genetic variation?
Where the characteristics of individuals vary due to genetic differences and mutations or environmental change.
What is the definition of species?
A group of organisms that can reproduce with one another, producing offspring that can also reproduce.
What are the steps of natural selection?
Variation
Change in environment
Competition/ adaptation
Survival of the fittest
Inheritance
Evolution
What is the variation stage of natural selection?
Individuals look slightly different, caused by mutations.
What is the competition stage of natural selection?
Some individuals are more able to survive than others, as they are better adapted to their environment, due to variation.
What is survival of the fittest stage of natural selection?
The individuals that are more adapted survive, whereas the others die off.
What is the inheritance stage of natural selection?
The fittest individuals reproduce, and their offspring inherit the characteristics that helped their parents survive.
How does evolution occur?
When the natural selection cycle repeats.