Convergent phenotypic evolution often results from similar genetic changes in independent species by a process known as parallel evolution. Sometimes, convergent evolution results from the evolution ...

Horizontal lines run left to right, parallel to the horizon, with slope 0 and equation y = k. Vertical lines run top to bottom, perpendicular to the horizon, with undefined slope and equation x = k.

Although advances have been made in reducing mortality rates and improving survival, cancer is the leading cause of death among men and women under 85 years of age in the United States 1. Most deaths ...

Two lines have equations \(y = {m_1}x + 3\) and \(y = {m_2}x - 7\). If the lines are parallel then \({m_1} = {m_2}\) and if \({m_1} = {m_2}\) then the lines are parallel. The gradient of a line which ...

If lines are perpendicular to each other then \({m_1} \times {m_2} = - 1\) conversely if \({m_1} \times {m_2} = - 1\) then the lines are perpendicular to each other.