Final answer:
The last 200 years have witnessed secular trends in human growth and development, primarily due to economic growth improving the average person's standard of living. These changes encompass increased average heights and shifts in developmental milestones, reflecting transformations in nutrition, healthcare, and living conditions.
Step-by-step explanation:
Over the past two centuries, economic growth has profoundly impacted the human condition, leading to significant secular trends in human growth and development. The concept of modern economic growth began in the 1800s and has brought about a dramatic rise in the average person's standard of living, compared to the relatively stagnant conditions experienced for centuries prior. This shift has resulted in changes in nutrition, health care access, hygiene, and living conditions, contributing to increased human growth patterns, such as taller average statures and later onset of puberty in younger generations.
Before this era, while the wealthy could enjoy certain luxuries, the vast majority of people lived at or just above subsistence levels, with little change in their standard of living. The rapid and sustained economic growth seen in the last two centuries has altered this, with improvements in the average person's standard of living, influencing the physical, intellectual, and developmental characteristics of human populations over successive generations.