{
"$type": "site.standard.document",
"bskyPostRef": {
"cid": "bafyreia5i3tbcp5evwq3nc6zcll2xyzowvhncowkjv6w5ad7sgyjzhvsiu",
"uri": "at://did:plc:7ltlvigjik37fxbx2bat4p22/app.bsky.feed.post/3mi3mzsvdvvv2"
},
"coverImage": {
"$type": "blob",
"ref": {
"$link": "bafkreiehegxdyqxtd7nf2nbifsjjtekvlxaiiidodiluoitt225uuzh6tu"
},
"mimeType": "image/jpeg",
"size": 87834
},
"path": "/biology/chin-evolution-body-part-function-human/",
"publishedAt": "2026-03-27T23:47:44.000Z",
"site": "https://refractor.io",
"tags": [
"Continue Reading",
"Biology",
"Science",
"Evolution",
"Human"
],
"textContent": "Male nipples. Whale pelvic bones. Vestigial hind limbs in snakes. Evolution is full of features that look purposeful. But upon closer inspection, science tells us that they are actually by-products of development and shifting gene expression. New research suggests the human chin may be one such evolutionary spandrel, a term biologists use for a trait that emerges as a consequence of other changes rather than as a direct adaptation.\n\nContinue Reading\n\n**Category:** Biology, Science\n\n**Tags:** Evolution, Human",
"title": "Chins are unique to humans and possibly an evolutionary accident"
}