1. AP Biology Chapter 15 – Mechanisms of Evolution
15.1 Evolution is Both Factual and the Basis of Broader Theory

2. 15.1 #1 Why is evolution the unifying principle in biology?
Things change all the time
These changes drive the origin of species
These changes drive the extinction of species
These changes drive the diversity of life

3. 15.1 #2 What was the significance of Lamarck’s ideas?
His ideas led to the field of epigenetics – which is the study, in the field of genetics, of phenotypic trait variations that are caused by external or environmental factors that switch genes on and off and affect how cells read genes instead of being caused by changes in the DNA sequence

4. 15.1 #3 What was the mechanism Lamarck proposed?
is the idea that an organism can pass on characteristics that it acquired during its lifetime to its offspring (also known as heritability of acquired characteristics)

5. 15.1 #4 How does the present knowledge of molecular biology and genetics refute his mecahnism.?
Traits are passed down by genes and DNA, and changes in DNA (mutations) not by acquired characteristics

6. 15.1 #5 Summarize Darwin’s theory of evolution by natural selection
Species change over time
Divergent (different) species share a common ancestor
What produces change in species is natural selection – the differential survival and reproduction of individuals in a population based on variation in their traits

8. 15.1 #6 What was the significance of Darwin’s theory of evolution by natural selection?
It provided the first, and only explanation of the existence of adaptations in nature.
It got proven and accepted after Mendel’s statistical analysis of genetic traits.