Biological evolution changes that take place in genetic and physical chracteristics of a population or group of organisms over time. Adaptive significance effectiveness of behaviour in aiding organisms to adjust to changing environmental conditions. Psychologists research how past environmental conditions favoured certain behaviour and how immediate envornment influences choices interested in ultimate causes of behaviour and proximate causes. Ultimate causes evolutionary conditions that have slowly shaped behaviour of species over generations. Proximate causes - immediate environmental events and conditions that affect behaviour. Evolutionary psychology studies ways which organism"s evolutionary history contributes to development of behavioural patternsa nd cognitive strategies related to reproduction and survivial during lifespan. Culture sum of socially transmitted knowledhe, customs, and behaviour patterns common to particular group of people. British naturalist alfred russel wallace also devised theory natural selection same time as darwin. Met captain fitz roy in 1831 unpaid naturalist companion on beagle, ten-gun brig converted to ocean research vessel that ended in 1836.