Jack Horner - How to Build a Dinosaur

The digits (fingers and/or toes)of humans are seemingly derived from those of early fish and tetrapods. Though, these creatures most likely could not walk on land, only on the ocean floor and in shallow water. Digits could, in theory, be modified during their initial growth, as evidence shows that this is what happens during evolution. Therefore, (once again theoretically,) it should be possible to modify digits of creatures, giving them the characteristics of their ancestors. In other words, reverse evolution. All of this does (mostly) make sense to me, and seems reasonably fool-proof, though it has not yet been performed.

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Jack Horner - How to Build a Dinosaur

Mice and insects are used in scientific experiments because their body systems are so similar to humans. Also, i believe another reason small animals are used for testing is because they will process anything introduced into their body much more quickly, due to faster heart rate and smaller size. Smaller sizes of chemicals would need to be used too, so money and materials can be conserved. Since DNA is so similar in every organism, and is made up of proteins, which can alter external as well as internal physical features, by modifying DNA devolution, or reverse-evolution, is theoretically possible. I believe that it is thought provoking, having DNA similar to a fly's yet being completely different in almost every other way.
Pages 140-160

Jack Horner - How to Build a Dinosaur

Similarities in the vertebrae, pelvis, hind limb, and pectoral arch show that birds may very likely have descended from dinosaurs. Many fossils have been discovered with a "wishbone" and evidence of feathers, showing a link between dinosaurs and birds (even though these dinosaurs most likely could not fly). The best example of a bird-dinosaur hybrid was found in China, incredibly preserved with it's last meal still in it's stomach, and feathers still intact!

Pages 120-140