On The Origin of Smooching, Mausoleum Madness, Chubby Cheetahs
October 7, 2026
AI Summary
5 min read“The only non-human animal we have seen using tongue is the bonobo,” says Riley Black, paleontologist and author of the forthcoming Tyrant Lizard Queen. This detail, from a study that won the 2026 Ig Nobel Prize in Biomechanics, anchors an episode of The Weirdest Thing I Learned This Week that traces three strange threads: the evolutionary origin of kissing, the architectural history of mausoleums, and a fossil cat that turns out not to be the cheetah everyone thought it was. Each story is about a tidy narrative that falls apart under closer scrutiny, and each leaves behind a more interesting, less certain truth.
Why Do We Kiss? A Definitional Problem
The kissing segment begins with a puzzle: we don’t know why humans kiss, when it started, or even what counts as a kiss. Mesopotamian texts show romantic kissing existed 4,500 years ago, but by then it was already established. A 2015 survey of anthropological records found that while 90% of cultures have parent-child kisses, fewer than half have romantic lip-to-lip kissing. Some cultures nibble eyebrows instead. The problem, the hosts explain, is that researchers have never agreed on a definition.
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What you'll learn
- 1 On The Origin of Smooching, Mausoleum Madness, Chubby Cheetahs
- 2 (02:03) **Welcome & Guest Introductions** - Rachel welcomes Amanda Reed (returning guest) and Riley Black (promoting new book *Tyrant Lizard Queen*)
- 3 (04:40) **Teasers: Mausoleums, Cheetahs, and Kissing** - Each host previews their weird fact
- 4 (06:04) **2026 Ig Nobel Awards Speed Run** - Rachel runs through the year's winners before diving into the kissing prize
- 5 (19:48) **The Kissing Study: Defining the Undefinable** - Rachel presents the 2026 Ig Nobel in Biomechanics: devising a more precise definition of kissing
- 6 (21:34) **Ancient Kissing History** - What we know about kissing through human history
- 7 (25:09) **The Phylogenetics of Smooching** - How researchers traced kissing through primate evolution
+ Full timestamped outline available in the app
Guests on this episode
Show Notes
Amanda Reed and Riley Black join the show to discuss the fat American cheetah, weird mausoleum culture, and where the heck kissing came from.
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