Group membership is of elementary importance to our wellbeing and because humans are very sensitive to signals of exclusion, a silence is generally taken as a sign of rejection.
Because boys generally have more acute vision, learn best through touch, and are physically more active, they need to be given "hands-on" lessons where they are allowed to walk around.
They argue that information about cultures during the empiricist era typically came from anthropologists who brought with them a prepackaged set of conscious and unconscious biases.
Museums that house Renaissance oil paintings typically store them in environments that are carefully kept within narrow margins of temperature and humidity to inhibit any deterioration.
They generally tend to share very similar tastes in music and clothes, they spend their money in having a good time, and save for holidays or longer-term plans when necessary.
Support for this idea came from the observation that long-lasting climax communities usually have more complex food webs and more species diversity than pioneer communities.
Lengthy periods of economic stagnation or decline have almost always left society more mean-spirited and less inclusive, and have usually stopped or reversed the advance of rights and freedoms.