Chapter 54.3, Problem 1R

Summary Introduction

To review:

With reference to Figure 1, whether the changes in life expectancy for humans over the past 175 years suggest an environmental or a genetic cause. Based on its results whether the large differences in human lifespan for Japan versus Anglo (Figure 2) are the result of genetic or environmental factors.

Given:

The life expectancy of females, since 1840 is represented in Figure 1. The bold line depicts the linear trend in the life expectancy and the dashed line depicts the extrapolated trend (assuming that the trend would continue in the future).

Figure 1

The life expectancy of both males and females is compared at the time of birth in the year 2016 in Figure 2. Equal male and female life expectancy is represented by solid line and the population size of a country is indicated by the size of the bubble.

Figure 2

Introduction:

Life expectancy or longevity for human life depends on both genetic and environmental factors. Human life history trait is much complex and varies among different populations, families, and individuals. Most of the traits associated with life expectancy depend on genetic factors and few depend on environmental factors.