From National Geographic（国家地理杂志）:
"Once some groups of modern humans began their migration out of Africa some 60,000 years ago, they kept going until they had spread to all corners of Earth. How far and fast they went depended on climate, the pressures of population, and the invention of boats and other technologies. Less tangible qualities also sped their footsteps: imagination, adaptability, and an innate curiosity about what lay over the next hill."
出处：https://education.nationalgeographic.org/resource/global-human-journey/
今早看到这张特殊的地图，和（链接）文中遗传学家对“现代”人类喜欢冒险基因变异的说法，觉得很有趣。说不定你和我都是属于这20%有"DRD4-7R"冒险基因的人（或他们的家人），所以我们会像蒲公英的绒球一样，飘到了离第一故乡这么远的地方哈。
