Anyone who’s ever looked around the family dinner table at a celebration and wondered at how such a disparate group of people could be related to each other understands—whether they realize it or not—one of the primary difficulties of developing animal crossbreeding programs. No matter if it’s cows or people, individual traits such as height or personality are so varied that it can be difficult to perceive the underlying family resemblances. One way scientists overcome this challenge is by studying large sample sizes. Patterns that might not reveal themselves in a handful of instances become clearer when the lens zooms out to take in thousands of cases. Grandma’s longevity and good health are no guarantee that you won’t get hit by a bus on the way home. But thousands of data points about mortality can help scientists figure out how much of life expectancy is hereditary and how much is…
View original post 1,013 more words