How Did Dinosaurs Go Extinct?
66 million years ago, the reign of the dinosaurs ended suddenly. Here's what happened.
The Asteroid Impact
The Chicxulub Impactor
A 10-12 kilometer asteroid struck the Yucatan Peninsula (modern Mexico):
- Impact energy: 100 trillion tons of TNT
- Crater: 180 km wide, 20 km deep
- Tsunamis: Hundreds of meters high
- Debris ejected into space, rained back as fire
The Aftermath
- Global wildfires
- Earthquakes and tsunamis
- Intense heat pulse
- Impact winter: Dust and soot blocked sunlight
- Temperatures dropped drastically
- Photosynthesis collapsed
- Food chains broke
- Acid rain
- Ocean acidification
- ~75% of species went extinct
Why Did Dinosaurs Die But Others Survive?
- Small animals (less food needed)
- Burrowers (protected from heat)
- Fresh water creatures (buffered from acid rain)
- Birds (small, versatile dinosaurs)
- Early mammals
- Large animals (huge food requirements)
- Animals dependent on photosynthesis-based food chains
- Marine reptiles
The Deccan Traps
Massive volcanic eruptions in India (Deccan Traps) were already stressing ecosystems. Some scientists argue this made the extinction worse — or was the primary cause.
Most evidence points to the asteroid as the primary trigger.
The Legacy
The extinction cleared ecological niches. Mammals, previously small and marginal, radiated into every available role — eventually producing us.
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