Why were all animals bigger before?
Roughly 300 million years ago, giant insects scuttled around and fluttered over the planet, with dragonflies bearing wingspans comparable to hawks at two-and-a-half feet. Back then, oxygen made up 35 percent of the air, compared to the 21 percent we breathe now.If the atmosphere in the past held …
The Short Answer
Roughly 300 million years ago, giant insects scuttled around and fluttered over the planet, with dragonflies bearing wingspans comparable to hawks at two-and-a-half feet. Back then, oxygen made up 35 percent of the air, compared to the 21 percent we breathe now.If the atmosphere in the past held more oxygen, tracheae could be narrower and still deliver enough oxygen for a much larger insect.
Analysis
Key Concepts: Oxygen, percent, roughly
This explanation focuses on oxygen, percent, roughly and spans 62 words across 2 sentences. The depth is typical for Animals questions (category average: 68 words), striking a balance between accessibility and completeness.
What This Answer Covers
This is a focused, single-point answer that gets directly to the core of the question without detours.
How This Compares in Animals
Ranked #241 of 500 Animals questions by answer depth (top 49%). 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 all animals bigger before?
Roughly 300 million years ago, giant insects scuttled around and fluttered over the planet, with dragonflies bearing wingspans comparable to hawks at two-and-a-half feet. Back then, oxygen made up 35 percent of the air, compared to the 21 percent we…
How detailed is this explanation compared to similar Animals questions?
This is an above-average answer at 62 words, ranked #241 of 500 Animals questions by depth. The key concepts covered are oxygen, percent, roughly.
What approach does this answer take to explain all animals bigger before?
The explanation uses direct explanation across 62 words. It is categorized under Animals and addresses the question through 1 analytical lens.