In response to my cattle v. people post earlier today, Tom Swetnam asked if I had data for sheep:
@jfleck I have been looking for a graph like that! Do you have sheep numbers? Multiple times cows in early decades, I think.
— Tom Swetnam (@Tom_Swetnam) January 10, 2016
USDA’s data only go back to 1920, but it is as Tom suspected:
If you add in horses and burros, and take it as the sum of all livestock vs humans, I think it may be only last few years that humans have gained the numerical advantage!