https://www.thegreatcoursesplus.com/language-families-of-the...
One of the topics in McWhorter's research is about how languages become streamlined when they are learned by adults as a second language. English, Mandarin, and Swahili all show evidence of this (for English, it seems related to the Vikings).
Related post:
https://www.theatlantic.com/international/archive/2016/06/co...
For people interested in human languages (or people who don't yet know they're interested in human languages), you might enjoy the courses he's done for Great Courses (paid but worth it, available on ~Amazon):
(1) The Story of Language: covers the topic of language evolution; how languages change over time, how new words are introduced, how languages mix (due to e.g. invasions), pidgins/creoles
(2) Language Families of the World: a survey of what languages currently exist, features of languages in different families
If you're interested in an entertaining overview of all of the world's languages, I can recommend the course Language Families of the World by The Great Courses - 34 byte-sized (half hour) lectures.
https://www.thegreatcourses.com/courses/language-families-of...