Question

for a long time, people have tried to explain how life on earth has changed. two of the most famous theories came from jean - baptiste lamarck and charles darwin.

• jean - baptiste lamarcks theory (lamarckism): lamarck believed that organisms could change during their lifetimes by using or not using certain body parts. he thought that these changes, which he called acquired characteristics, could then be passed on to their offspring. his idea is often summarized as the \inheritance of acquired traits.\

• charles darwins theory (darwinism): darwins theory, on the other hand, is based on the idea of natural selection. he proposed that there is variation within any population of organisms (meaning they are not all exactly the same). some of these variations might be more helpful for survival in a particular environment. those with the helpful traits are more likely to survive, reproduce, and pass those traits on to the next generation. this is often called \survival of the fittest.\

simple questions:

1. according to lamarck, how could an organism change during its lifetime?
2. what did lamarck call the traits that an organism develops during its life?
3. according to darwin, what is naturally present in any group of living things?
4. what is the key idea behind darwins theory called?

topic 3: the giraffe example: lamarck vs. darwin
guided notes:

the long neck of the giraffe is a classic example used to explain the difference between lamarcks and darwins theories.

• lamarcks explanation (the giraffes effort):
• lamarck would have said that the original giraffes had short necks.
• these giraffes stretched their necks to reach leaves on higher branches.
• because they were constantly stretching, their necks got a little longer during their lifetime.
• this acquired trait of a longer neck was then passed down to their babies.

Explanation:

1. According to the text, Lamarck believed organisms could change during their lifetimes by using or not using certain body parts.
2. Lamarck called the traits that an organism develops during its life acquired characteristics.
3. Darwin proposed that variation is naturally present in any group of living things.
4. The key idea behind Darwin's theory is called natural - selection or "survival of the fittest".

Answer:

1. By using or not using certain body parts.
2. Acquired characteristics.
3. Variation.
4. Natural selection or "survival of the fittest".