Going into a daze or dormancy, saving energy for metabolic processes (winter sleep of a gopher). Maintaining the constancy of the internal environment, despite fluctuations in the effects of external factors (warm-bloodedness of birds and mammals). Avoidance of unfavorable conditions, active search for other habitats (bird flights, fish migration).
Remember: The process of learning a person lasts a lifetime. The value of the same knowledge for different people may be different, it is determined by their individual characteristics and needs. Therefore, knowledge is always needed at any age and position.