Over the time of the study, and especially in the past 10 years, there's been a very severe and deepening drought in the Southwestern U.S., and it turns out that the colonies that conserve water, that stay in when it's really hot outside, and thus sacrifice getting as much food as possible, are the ones more likely to have offspring colonies.
これまでの研究の中で 特にこの10年間は 南西部アメリカでは 厳しい干ばつに襲われていますが 水を節約するために 猛暑の日は 巣の中に留まり 最大限の収穫を犠牲にするコロニーが より’多くの子孫を残す事が解りました それまで 154番のコロニーは