These are among the most mysterious questions in prehistory, and have long been studied using traditional archaeology: bones, artefacts and so on.
In recent years, however, the field has been revolutionised by genetic data. DNA from living people and preserved remains has both enhanced and transformed our understanding of the continents’ First Peoples (those who were on the continent before Europeans arrived) and how they got there.
Jennifer Raff is a genetic anthropologist at the University of Kansas who has been involved in many studies of ancient American DNA, so she is an ideal guide to the subject. Her book Origin bills itself as “a genetic history of the Americas”, and it largely delivers on that promise. The final third of the book, in particular, draws on genetic and archaeological evidence to tell the story as we see it now.
This section is a model of clear and nuanced explanation: Raff highlights the uncertainties and caveats, but doesn’t allow them to overwhelm the story.
Any dog owner knows how hard it is to leave their pup for an extended period of time.
We wonder: Do they miss us when we’re gone? Do they know how long we’ve been gone for? Or even worse, do they think we’ve abandoned them?
The way humans are excitedly greeted by their dogs upon return — and the way many whine when we leave — suggests they recognize our absence, and mourn it. However, it’s hard to know what is really going on in a dog’s brain — perhaps they just miss the food we give them? — partly because we can’t really communicate with them.
It’s something that many of us reckon with: the sense that we’re not quite as sharp as we once were.
I recently turned 42. Having lost my grandfather to Alzheimer’s, and with my mom suffering from a similar neurodegenerative disease, I’m very aware of what pathologies might lurk beneath my cranium.
In the absence of a cure for Alzheimer’s and other forms of dementia, the most important interventions for upholding brain function are preventive — those that help maintain our most marvelous, mysterious organ.
Based on the science, I take fish oil and broil salmon. I exercise. I try to challenge my cortex to the unfamiliar. As I wrote my recent book, A History of the Human Brain, which recounts the evolutionary tale of how our brain got here, I began to realize that so many of the same influences that shaped our brain evolution in the first place reflect the very measures we use to preserve our cognitive function today.
Dog owners might not be too impressed when they’re able to point out a fallen piece of chicken or a thrown stick to their pooch, but dogs’ ability to follow that seemingly simple gesture places them in rare air in the animal kingdom.
Some research suggests that even chimpanzees, our closest evolutionary relatives, don’t understand pointing as well as dogs.
For decades, researchers have debated whether dogs obtain their ability to understand pointing by spending time with humans and learning it or if our furry companions are born with a capacity to comprehend this deceptively complex feat of communication.