diff --git a/content/daily-notes/2024-11-22.md b/content/daily-notes/2024-11-22.md
index cdd6a079..8e257228 100644
--- a/content/daily-notes/2024-11-22.md
+++ b/content/daily-notes/2024-11-22.md
@@ -9,6 +9,14 @@ This is a good bio of the man, with some funny one-liners.
 
 S3 has landed and it is pretty much the same as the last two seasons in its occasionally crude humor and fast-paced dialogue. I can't say it's the best thing in TV right now, but I keep going back for some reason.
 
+#### The Two Types of Human Laugh
+[The two types of human laugh](https://www.economist.com/science-and-technology/2024/11/20/the-two-types-of-human-laugh)
+
+> The findings, published this week in _Biology Letters_, are more than light entertainment. They could, instead, point scientists towards the evolutionary roots of laughter. After all, many mammals including dogs, squirrel monkeys, Barbary macaques and chimpanzees produce vocalisations during play that sound remarkably like laughter. One of the first things that infants do early in life is laugh. Even babies born deaf spontaneously produce laughter. Humans are not the only animals that tickle either. Macaques and chimpanzees both engage in the activity too.
+> 
+> All this suggests that laughter from tickling evolved over 10m years ago with the common ancestor that humans shared with these other primates. Dr Kamiloglu suspects that this early sort of laughter probably evolved to help primates build friendly relations, especially during play. With this in mind, she is now keen to study how infectious different sorts of laughs are. If the tickling laugh is one that truly evolved to bring primates together, it ought to be particularly infectious—but nobody has yet tested if it is.
+> 
+> As for all the other forms of laughter that only people produce, these probably evolved millions of years after tickling came along, when the human brain became complex enough to understand irony, slapstick and puns. But he who laughs last, it would seem, laughs longest.