Why do languages gain and lose sounds?

I attended a fascinating talk recently by Professor Andrew Wedel, who has discovered how to predict whether a language will gain or lose sounds.

Misunderstandings and borrowings

The history of language contact is the history of thinking that what other people said was the answer to the question that you asked.

"Thus were immortalised in generations of atlases such geographical oddities as Just A Mountain, I Don't Know, What? and, of course, Your Finger You Fool." ― Terry Pratchett, The Light Fantastic

Here are a few borrowed words showing that whoever appropriated it didn't really understand the language they got it from...

Which languages share sounds with English?

More accurately entitled, A typology of consonantal segment inventories of the world's most spoken languages, and also Welsh.

Intonation

What is intonation?

Intonation is the change in pitch which occurs over the course of a phrase. It is generally used to signify information about the utterance, like:

• whether it's a question or a statement
• which parts are new information and which are already known to both parties
• the attitude of the speaker towards the information

For example, you can use intonation (in combination with main stress, in English) to change...
"I never said she stole MY money" vs "I never said SHE stole my money"

Spelling reform: some unanswered questions

There are various arguments for and against spelling reform. But if we all agreed it was necessary, what are the problems we would face in finding a new standard?

The International Phonetic Alphabet

In order to write sensibly about phonemes and allophones, we need a phonetic writing system - one where each symbol stands for a single sound, and each sound has its own symbol. Most commonly used is the International Phonetic Alphabet (though frequently with some personalisation).