i. The data came from the UK Biobank, which contains genetic and medical data from half a million people.
ii. Intriguingly, this analysis suggests genetic contributions to intelligence and educational achievement are currently disfavoured by natural selection.
iii. Positive correlation means an association with successful reproduction; negative one means exactly the opposite.
iv. A study just published uses a new statistical method to examine how genetic contributions to certain human traits such as intelligence correlate With how many children a person has.