Why were there tons of super giant creatures like dinosaurs a few million years ago, but there aren’t now? Why did everything shrink in scale? Even a lot of bugs were much bigger then. Did Earth’s …
The prevailing theory is that our atmosphere had a lot more oxygen in it at the time (right now it's just over 20%). This let animals grow larger, especially with the scale of insects. Since most of them don't have a true respiratory system, they take in oxygen through their skin/exoskeletons.
The Short Answer
The prevailing theory is that our atmosphere had a lot more oxygen in it at the time (right now it's just over 20%). This let animals grow larger, especially with the scale of insects. Since most of them don't have a true respiratory system, they take in oxygen through their skin/exoskeletons. By having more O2 in the atmosphere, that made it easier to sustain larger size.
Analysis
Key Concepts: Atmosphere, oxygen, larger
This explanation focuses on atmosphere, oxygen, larger and spans 66 words across 4 sentences. The depth is typical for Animals questions (category average: 68 words), striking a balance between accessibility and completeness.
What This Answer Covers
The explanation opens with: “The prevailing theory is that our atmosphere had a lot more oxygen in it at the time (right now it's just over 20%).” It then elaboratesultimately building toward a complete picture across 4 connected points.
How This Compares in Animals
Ranked #225 of 500 Animals questions by answer depth (top 46%). This falls in the detailed tier — above average depth. The explanation goes beyond surface-level but keeps things accessible.
Frequently Asked Questions
Is there a simple explanation for why there tons of super giant creatures like dinosaurs a few million years ago, but there aren't now? why did everything shrink in scale? even a lot of bugs were much bigger then. did earth's gravity change?
The prevailing theory is that our atmosphere had a lot more oxygen in it at the time (right now it's just over 20%). This let animals grow larger, especially with the scale of insects. Since most of them don't have a true respiratory system, they…
How detailed is this explanation compared to similar Animals questions?
This is an above-average answer at 66 words, ranked #225 of 500 Animals questions by depth. The key concepts covered are atmosphere, oxygen, larger.
What approach does this answer take to explain there tons of super giant creatures like dinosaurs a few mil?
The explanation uses direct explanation across 66 words. It is categorized under Animals and addresses the question through 1 analytical lens.