[Campbell Biology P.800] What does a positive slope m > 0 in the regression line y = mx + b ... | Practice Question

What does a positive slope m > 0 in the regression line y = mx + b for hominin brain volume versus age indicate about hominin evolution, according to the provided text?

  • A: Mean brain volume decreased as hominin species evolved over time.
  • B: Mean brain volume increased as hominin species evolved over time.
  • C: Mean brain volume remained constant regardless of age.
  • D: The relationship between brain volume and age is not linear.

Explanation

According to the 'INTERPRET THE DATA' section, 'When m > 0, the line has a positive slope, meaning that the values of y become larger as values of x become larger.' In this context, y represents mean brain volume and x represents age. Therefore, a positive slope indicates that mean brain volume increased as hominin species evolved over time as age values become less negative or more positive, moving closer to the present .