Image: scientificamerican.com
The Story
Birds crossed the K–Pg boundary; no comparable fossil trail shows non-avian dinosaurs continuing afterward.
The strongest evidence concerns fossils near the boundary, not living descendants after it. New Mexico material once reported as hundreds of thousands of years younger became a test case for dating, reworking, and contamination; the conventional reading remains that the asteroid ended non-avian dinosaur survival, while birds crossed the catastrophe.
- Evidence standardA post-boundary fossil must be securely dated in place and shown not to have been reworked from older rocks.
- Current readingThe available mainstream account supports avian survival, not persistent non-avian populations.
- Scientific American presents the asteroid extinction as eliminating all nonbird dinosaurs while birds survived.
- The Smithsonian reports no evidence of living non-avian dinosaurs today and identifies birds as the surviving dinosaur group.
- The New Mexico survival claim faced controversy because fossils can be misdated or moved into younger strata by erosion or burrowing.
Source mix
4 of 9 institutional
- 4 Journals & institutions
- 3 News reporting
- 1 Forum, video, personal
- 1 Other / unclassified
Deeper Insight
Reworked or misdated New Mexico fossils muddy the clean ending. Extinction may have been a retreat, not a single stroke.
Dating and reworking disputes surround 30 New Mexico fossils placed roughly 500,000 years after the asteroid. The evidence is contested, but a bone near the boundary keeps one possibility alive: extinction may have been a long squeeze, not one clean stroke.
- What it could changeA confirmed post-impact dinosaur population would rewrite how scientists read the fossil record and mass extinctions.
- How it touches todayThe debate shows how one disputed bone can carry more weight than a mountain of tidy assumptions.
- Our futureWe could mistake a species' disappearance from view for its final breath, and miss the last refuge entirely.
- The originating discussion proposes that small or mid-sized non-avian dinosaurs might have survived in refuges such as Antarctica, while acknowledging that sustained modern populations are implausible.
- A Discover report describes 30 New Mexico fossils interpreted by James Fassett as evidence that dinosaurs survived the asteroid by roughly half a million years.
- A 2025 Science study revisits late-Cretaceous New Mexican dinosaur diversity and the possibility that earlier fossil sampling gave an incomplete picture of end-Cretaceous survival.
Sources · 9
- 4 Journals & institutions
- 3 News reporting
- 1 Forum, video, personal
- 1 Other / unclassified
What do these mean?
- Journals & institutions. Published in a peer-reviewed journal, or from a university, government body, court or other institution.
- News reporting. Journalism: newspapers, magazines and news sites.
- Forum, video, personal. Forums, social posts, video, blogs and personal accounts.
- Other / unclassified. A site we have not classified yet. This says nothing good or bad about it.
Featured · Primary source · science.org
Late-surviving New Mexican dinosaurs illuminate high end-Cretaceous diversity and provinciality | Science
Journal · peer-reviewed
Late-surviving New Mexican dinosaurs illuminate high end-Cretaceous diversity and provinciality | Science # Late-surviving New Mexican dinosaurs illuminate high end-Cretaceous diversity and provinciality Andrew G. Flynn https://orcid.org/0000-0002-1371-1878, Stephen L. Brusatte https://orcid.org/000
Read sourceAnalysis · reddit.com
What are your arguments that supposedly prove that certain dinosaurs were not extinct in the event "K—PG" or "meteor fall"?
Forum or personal account
I personally think it's impossible that any animal with more than 50kg has managed to survive with a sustainable population to be able to reach today's we have. Top comments: - Joke answer: Birds exist Real answer: I think there *is* a significant possibility that there were at least *some* Non-avian dinosaurs that survived the K-Pg extinction. Dinosaurs at the end of the Cretaceous were incredibl
Read sourceAnalysis · discovermagazine.com
Some Dinos May've Survived the Cataclysm | Discover Magazine
News reporting
Some Dinos May've Survived the Cataclysm | Discover Magazine # Some Dinos May've Survived the Cataclysm If mammals, birds, and lizards pulled through, why not some dinosaurs? Written by Barry E DiGregorio 2007-08-29T05:00:00 | 1 min read According to the going theory, a six-mile-wide asteroid slamme
Read source