Researchers pinpoint when the Vikings came to Canada. It was exactly 1,000 years ago.
So they were following the KLF.
In the year of our Lord Nine Ninety-Two, the Justified Ancients of Mu Mu set sail in their long boats on a voyage to rediscover the lost continent. After many months on perilous, stormy seas, their search was fruitless. Just when all seemed lost, they discovered AMERICA! The music you are about to experience is the celebration of the one thousandth anniversary of their founding of this great nation
This means that within a social group where knowledge is shared or individuals are specialists at certain tasks, brains may adapt to become more efficient, such as decreasing in size.
Yabbut this would mean that hunter-gatherers, should have larger brains. Some of those people still exist, and there are skeletons from recent hunter-gatherers who have disappeared.
How about they were starting to exceed the limits of the pelvic girdle, so infants with larger skulls tended to lead to more infant-mother mortality, so the trend towards a smaller brain/skull gained traction?
I read that itās not the pelvic girdle, the problem is that larger brains are huge energy sinks, and only in the last few hundred years have we gotten to a point where a mother could reliably* find the calories needed to support their larger brain and their childsā .
Sure, that is indeed two different things. But I still think itās a difference that doesnāt matter, because differing brain sizes has nothing to do with differing levels of intelligence.
new scientific studies across several animal species, including humans, are challenging the notion that brain size alone is a measure of intelligence. Rather, scientists now argue, it is a brainās underlying organization and molecular activity at its synapses (the communication junctions between neurons through which nerve impulses pass) that dictate intelligence.
(An old article, I know, but nothing more recent that I can find contradicts it.)
Work with corvids has shown that the structure of the brain can be way more important than size-they have shown much more ability than brain:body size ratios would say they should have.
ā In healthy volunteers, total brain volume weakly correlates with intelligence, with a correlation value between 0.3 and 0.4 out of a possible 1.0. In other words, brain size accounts for between 9 and 16 percent of the overall variability in general intelligence .
Itās complex. And if weāre including different species that have different kinds of brains, more so. And if we look at sex - women have brains that are 2.5% of their mass - men 2/%. Which says nothing about structure and complexity.
But among human populations and at the population level scale - I do think thereās an overall difference.
Okay, but just what is that difference? And why and/or how does it matter?
What about say, the population of basketball players? Surely they have larger brains than normal. But maybe theyāre smaller in proportion to their body sizes? If either is true, well, why should we care? Surely thereās nothing in all of that that we can use to say that basketball players are generally more or less intelligent than other people.
I suppose it would be something to study, if one took seriously the notion that brain size correlates in any at all significant way with intelligence. But it clearly doesnāt, and if we are getting less intelligent as a people (whatever THAT means, given how notoriously difficult it is to say what intelligence even is, let alone what this or that measure of it really measures), there are certainly many environmental factors that stand out as more likely suspects.
