Ready-to-3D-print files are in STL format, the most common 3D printing file format. Download the model, if necessary rescale it to fit your 3D printer (e.g. using Netfabb Basic), and then print it at home, at your local library or at a 3D hub.
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Cane toad (Rhinella marina). Skeleton and contrast agent filled lymph sac. Model is scaled 140% (18 MB)
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Tiger salamander (Ambystoma tigrinum) skull. Model is scaled 500% (36 MB)
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Reeve's muntjac (Muntiacus reevesi) skull. Model is scaled 95% (82 MB)
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Puff adder (Bitis arietans) head. Model is scaled 200% (14 MB)
"You can't even begin to understand  biology, you can't understand life, unless you understand
 what it's all there  for, how it arose - and that means evolution" - Richard Dawkins