Only Heritable Traits Drive Evolution
- For evolution to occur, traits must be heritable, passed from parents to offspring through DNA.
- Traits that are acquired during an organism’s lifetime, such as muscle growth or injuries, are not inherited and do not contribute to evolution.
A spider that loses a leg does not pass this trait to its offspring because the injury does not affect its reproductive cells.
Exam technique- Don't confuse heritable traits with acquired traits.
- Heritable traits are encoded in DNA and passed to offspring, while acquired traits, like muscle growth from exercise, are not.
Genes, Not Experience, Determine Traits
Heritability
Heritability refers to the ability of a trait to be passed from parents to offspring through genetic information.
- Heritability refers to a trait's ability to be passed to offspring via genetic material.
- Traits are encoded by genes, which are segments of DNA that determine characteristics.
- Offspring inherit a combination of alleles, forming their genetic blueprint.


