@redbaybound @jolly1766 @jimhubbell6177 @RadioFreeTom There is no study supporting that at the population level, across a wide variety of conditions.
There may be one for a particular setting. I don't know where you are getting it so I can't comment.
@红海湾地区@jolly1766@jimhubbell6177@RadioFreeTom没有研究支持在人口水平上，在各种条件下的这一点。
对于特定设置，可能有一个。我不知道你从哪里得到的，所以我不能发表评论。