They found, where forests had been cleared for cattle ranching and agriculture, plant and animal life was impoverished and remaining species invariably consisted of the same subset of the original flora and fauna. (sciencedaily.com)
«We found that both positive and negative selection are more effective on the same subset of radical amino acid changes,» Wu said. (uchospitals.edu)
And since a test must be reliable from year to year, it will measure that same subset every year. (educationnext.org)