It doesn't have to be misspelling. More likely it's forgetting which word it's supposed to be. I've only seen the word written/used in museums, so I'm unlikely

It doesn't have to be misspelling. More likely it's forgetting which word it's supposed to be. I've only seen the word written/used in museums, so I'm unlikely to remember whether it's a mastadon, mastodon, matadon, etc.