Short answers, pulled from the story.
Australian farmers extended the legal definition of lamb to include animals up to 13 months old. This change allowed producers to label sheep without permanent incisor teeth in wear as lamb rather than hogget.
Mutton refers to older sheep with more than two permanent incisors in wear. These distinctions rely on dental development rather than just calendar time.
Mongolia leads global per capita consumption at 45.1 kilograms annually according to OECD data from 2015. Greece tops European Union nations with 12.3 kilograms per person each year.
In South Asia, the word mutton often means goat meat instead of sheep meat. The Oxford English Dictionary notes this usage dates back centuries and over a third of the global goat population is slaughtered annually under this name.
The International Agency for Research on Cancer links unprocessed red meat to colorectal cancer risks. Studies associate higher consumption with increased cardiovascular disease and type 2 diabetes probabilities.