On geological timescales, human civilization is an event, not an epoch
Humans are now living in a new geological epoch of our own making: the Anthropocene. Or so we’re told. Whereas some epochs in Earth history stretch more than 40 million years, this new chapter started maybe 400 years ago, when carbon dioxide dipped by a few parts per million in the atmosphere. Or perhaps, as a panel of scientists votedearlier this year, the epoch started as recently as 75 years ago, when atomic weapons began to dust the planet with an evanescence of strange radioisotopes.
The CEO of children’s educational magazine Highlightsreleased a very pointed statement on our country’s current humanitarian crisis of an immigration policy on Wednesday. In the statement, titled ‘Highlights Stands Up for Immigrant Children,‘ Kent Johnson opened his public statement by reminding everyone that the mission statement for a company that services children and their education has a duty to try and help those children “become their best selves.”
When the Denisovan genome was sequenced soon after, in 2012, it revealed similar instances of interbreeding. We now know that small populations from all three Homo lineages mixed and mingled at various times. The result is that our DNA today is speckled with contributions from ancient hominin groups who lived alongside us, but did not survive to the present day. Genes from Denisovans and Neanderthals are not present in everyone’s DNA — for example, some Africans have neither, while Europeans have just Neanderthal genes. But, these genetic echoes are loud enough to stand out clearly to scientists.