MAMMALS IN TIME
from the first synapsid to us · 320 million years on one axis
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VERTEBRATES IN TIME
when each group appeared · five hundred million years on one axis
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BASIC PHYSICS FORMULAS
fifteen formulas · every letter explained beneath it
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ANIMALS
the main branches — from comb jellies to chordates · who is actually related to whom
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VERTEBRATES
from lamprey to bird · and why "fish" and "reptiles" are not groups
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IMPERIAL UNITS
convert in your head · without a calculator
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