It is said that variety is the spice of life and certainly the more we look, the more evidence we find that diversity and variety is good in all sorts of ways.
Horses evolved on a very diverse diet, with a wide range of grasses, legumes, forbs and herbs available, not to mention shrubs and small trees to browse on as the need arose. Their natural diet varied from season to season and even day to day. Choice, they had aplenty! Once we came along and the grazing and hay became predominantly ryegrass and the “short” feed the processed by-products of the human food industry, it must all have seemed pretty poor by comparison. Taped off paddocks with no access to hedges and over-grazed grass is a very limited substitute for plains abundant with diverse plant forms.