Fall of the Roman Empire, polygenic score edition
We have a new study out: Piffer, D., Dutton, E., & Kirkegaard, E. O. W. (2023). Intelligence Trends in Ancient Rome: The Rise and Fall of Roman Polygenic Scores. OpenPsych,…
A plethora of evidence for genetic influence of American race-ethnic gaps in intelligence
Back in 2021, Russell Warne wrote a nice summary article about race differences in intelligence: Warne, R. T. (2021). Between-group mean differences in intelligence in the United States are> 0%…
From riches to rags to riches
One of the interesting lines of evidence about the importance of human capital in wealth disparities comes from examples of how groups can recover from setbacks. There's several examples to…
Cannabis probably causes schizophrenia
A lot of countries are currently pondering whether they should legalize or decriminalize the sale of cannabis for recreational use. Cannabis is generally considered a fairly safe drug, at least,…
Can we pick the best sperm?
A lot of people are interested in embryo selection. Why? When people reproduce through IVF, they will generate more than one viable embryo. Which one to choose? The general approach…
Heritability, race, and police bias: Kareem Carr’s blunder
This was given to me as an example, so let's cover it even though it's two years old. Archived. So let's try his idea out. Here's what I did (R…
Book review: A Short History of Humanity: A New History of Old Europe by Johannes Krause
I read this book the other day and it's worth reviewing in some detail. Krause, J., & Trappe, T. (2022). A short history of humanity: A new history of old…
New paper: On group differences in the heritability of intelligence: A reply to Giangrande and Turkheimer (2022)
So it was finally published, our reply to our frenemies Eric Turkheimer and his student Evan J. Giangrande. For good measure, it's these two guys: The saga begins in 2020:…
High heritability does mean that social interventions likely won’t work well
The scientific literature is full of claims like this one (Paige Harden 2021): This hereditarian pessimism about the possibility of social change, however, is based on a fundamental misunderstanding of…
A theory of Ashkenazi genius: intelligence and mental illness
I want to put together a theory to explain a putative phenomenon: Ashkenazi Jews have more geniuses relative to non-Jewish Europeans (gentiles) than one would expect based on their average…