A closer look at the fertility behavior of the poor is important because of the extensive literature on the "replacement effect" of high infant mortality.
By 2007, the rate had dropped to 11.2 per 100, 000 people and suicide was the 11th leading cause of death in the United States, accounting for 34, 598 deaths.
But compared with that group, the risk of dying from all causes was twice as great among the sun avoiders and 40% higher in those with moderate sun exposure.
Scientists are beginning to understand the genetic basis of tardigrades death-defying superpowers. And what they re learning may have profound implications for human health.