Night Lizards That Survived the Dinosaur-Killing Asteroid
How Modern Lizards Survived the Asteroid That Killed the Dinosaurs
When the colossal asteroid struck the Yucatán Peninsula 66 million years ago, it wiped out more than 75% of Earth’s species — including all non-avian dinosaurs. Yet, one surprising group of lizards survived: the night lizards, or family Xantusiidae.
1. What Are Night Lizards?
- Genera: Xantusia, Lepidophyma, Cricosaura
- Traits: Secretive, small-bodied, crevice-dwelling, viviparous (give live birth)
- Range: Southwestern U.S., Central America, Cuba
2. How Did They Survive?
Recent research published in Biology Letters (via Phys.org) shows that these lizards lived within 500 km of the Chicxulub crater. Their survival may be due to:
- Low metabolic rate
- Small clutch size (1–2 young)
- Microhabitats like tree bark, rocks, and caves
“Night lizards are the only terrestrial vertebrate family known to survive the K–Pg extinction so close to the impact zone.” — Chase Brownstein, Yale University
3. Modern Species and Their Habitats
| Species | Location | Status |
|---|---|---|
| Xantusia vigilis | California, Nevada | Least Concern |
| Lepidophyma sylvaticum | Tamaulipas, Mexico | Data Deficient |
| Cricosaura typica | Cuba | Rare |
4. Evolutionary Importance
This discovery overturns assumptions that only wide-ranging, high-reproducing species survived the K–Pg extinction. Night lizards show how isolation and stable niches offer resilience.
5. Where You Can See Them
Today, you can find night lizards in:
- El Cielo Biosphere Reserve (Mexico)
- Desert regions of California and Nevada
- Forest habitats in Cuba
6. Expert Quotes
"It’s almost as if their distribution sketches a circle around the crater." — Chase Brownstein
"Statistically, that shouldn’t have happened." — Nathan Lo, University of Sydney
7. Learn More
- Yale University News
- Smithsonian Magazine
- Live Science
Conclusion
The story of night lizards is not just a tale of survival—it’s a living reminder of nature’s resilience. From ancient times to modern forests, these tiny reptiles continue to teach us about evolution, adaptation, and endurance.
Filed under: Animals wildlife

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