deletions | additions       diff --git a/Adding Traits and Yields.md b/Adding Traits and Yields.md  index 5957b6d..9a323b6 100644  --- a/Adding Traits and Yields.md  +++ b/Adding Traits and Yields.md 
...
# Adding [Adding  a [Covariate](http:www.betydb.org/covariates/new) Covariate](http:www.betydb.org/covariates/new)  Covariates are required for many of the traits. Covariates generally  indicate the environmental conditions under which a measurement was