Understanding Biological Behaviour
Your behaviour isn't just random - it all starts with biology. The biological approach assumes that everything we do has a physical cause, meaning our biological structure directly influences how we behave.
Scientists use twin studies to figure out what's inherited versus what's learned. Monozygotic twins (identical) share 100% of their genes, whilst dizygotic twins (non-identical) share about 50%. When researchers compare concordance rates between these twins, they can work out how much genetics influences specific traits.
Adoption studies offer another piece of the puzzle. By comparing adopted children to both their biological and adoptive parents, researchers can separate nature from nurture influences.
Your genotype is your complete set of genes, but your phenotype (what you actually look like and how you behave) equals your genotype plus your environment. Remember that dominant genes always show up, even with just one copy, whilst recessive genes need two copies to appear.
Key Point: Charles Darwin's theory of natural selection explains how behaviours that help survival and reproduction get passed down through generations, even if some traits become maladaptive in our modern environment due to genome lag.
