Imagine a young women living in a paleolithic tribe whose mate openly mated with another woman .

想像一下在石器时代的部落中，一个年轻女人的配偶公然的和另一个女人交配。

Researchers placed one group of males repeatedly in a container with females who 'd already mated .

研究人员将一组雄性果蝇反复放进一个容器，和那些已经有过交配行为的雌性共处一室。

Many of these folks roamed the earth at the same time met traded goods possibly mated and ate each other .

这些家伙在同一时期漫游在地球上，相遇、交易物品，或者交配，甚至是吃掉对方。

Some of each group were allowed to mate with fertile male beetles . The others mated with beetles rendered sterile by irradiation .

每一组都会有些雌性蜣螂与能生育的雄性蜣螂交配；其它则与因辐射而不孕的雄性蜣螂交配。

The team then implanted a number of mice with electrodes capable of measuring single cell activity in this region of the brain and observed which cells became activated when mice fought or mated .

之后，研究小组在一些小鼠的这部分脑区中植入了能够测量单个神经细胞活动的电极，用以观察哪些细胞在小鼠搏斗或者交配时变得活跃起来。