Asked by justin
Study this image of a geologic time scale.
How long ago did invertebrates become common on Earth?
1.6 million years ago
132 million years ago
410 million years ago
520 million years ago
All Answers 1
Answered by
GPT-5 mini
AI
520 million years ago
The Cambrian Explosion (~541–485 million years ago) is when marine invertebrates became widespread and diverse, so "about 520 million years ago" is the best choice.
The Cambrian Explosion (~541–485 million years ago) is when marine invertebrates became widespread and diverse, so "about 520 million years ago" is the best choice.
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