BB cream is promoted as an all-in-one facial cosmetic product to replace serum, moisturizer, primer, foundation and sunblock. It can be worn alone as a tinted moisturizer, over serum and moisturizer as a regular foundation, and under powder, depending on the desired amount of coverage. 1  1 History.  2 Formulations.
Definition. Naturalistic observation is research that involves studying the subject of interest in its own environment, as it would occur in day-to-day life. The subject of interest may be human or non-human or it can be the behavior of living things or the interactions of non-living things with their environment.
In overt observation, the observed is aware of the observer; in naturalistic observation of humans, for ethical reasons, only overt observation can be used. Ad. One drawback to naturalistic observation is that researchers cannot manipulate, control, predict, or even fully understand variables.