“Lead pollution levels from the Middle Ages preserved in an ice core taken from the Colle Gnifetti glacier in the Swiss Alps reflect political upheaval in England. [When] a new monarch was secure, there were usually major building projects [that] produced more pollution.”
– Jason Urbanus in “History in Ice”, Archaeology, July/Aug 2020
Deep time (e.g. the time since hominids first evolved; the Anthropocene era, or the projected time until the sixth extinction) is of increasing interest to humans in many fields. Geneticists like Adam Rutherford look at the history of human DNA; archaeologists identify sites where “humans” hunted 400,000 years ago in England; stationary indigenous peoples trace their history back 5,000 to 50,000 years; and authors, restorationists, and the UN attempt to reverse the ongoing sixth extinction.
Expanding our knowledgebase and our present thinking to time scales that matter to life on earth makes it much easier to grasp the follies of the self-destructive Anthropocene era, and to see that to continue them would be fatal to more than humans. The extinctions since the 1970s—within the scale of the human lifetime—have given us more than enough warning to conclude that we must begin to change now, and to change quickly.
Has anyone in your vocational or avocational spheres been discussing deep time? If so, you, too, can help to catalyze change by joining the conversation.
Likewise, ancient ways of food production—such as sustainably-harvested Oregon lichens—may inspire you to enhance rather than destroy habitat in your garden. In addition to the “Three Sisters” (squash, beans, and corn), or to present-day “shade-grown coffee,” the early Europeans who followed the retreating glaciers created forest gardens—some of which still exist. Mesolithic people brought hazel, nettle, rowan, pear, and many other plants today considered weeds. With hunting, they created a more nourishing diet than can be obtained today; their gardened forests have lasted for millennia, as have coppicing and pollarding techniques, tree trellising, and ancient hedgerows, and post-glacier grain and legume mixes. On the cautionary side, monocultures of trees is increasing bark beetle outbreaks; the more mixed the species, the less likely the spread of disease. One way around that may be the little forest islands that have stood for 10,000 years in South America. Geographer Umberto Lombardo sees in them early forms of agriculture; archaeologists see the seasonally-flooded grasslands that stand between them as a key to understanding the islands.
The history of land modification going back ten thousand years corroborates the Ruddiman “early anthropogenic hypothesis”—the idea that agriculture was the major cause of global warming for thousands of years, until the 1950s. ArchaeoGLOBE indicates that pre-agricultural transplanting, hunting, and fire modified landscapes around the globe before 10,000 years ago. The flip side of this is that humans have had a profound impact on life on earth, sometimes enhancing biodiversity. This is a possibility that suggests we can still avert the sixth extinction.