Shin Godzilla Forms 1 and 2

Forms 2 and 3. Form 1 is never seen in the film. It even says form 2 and form 3 in the pictures. 

Yeah those are form 2 & 3, but still interesting nonetheless!

The eyes are so big because the forms are smaller. Eyeballs don't grow, they stay the same size from birth--Hence why they look so much smaller in his final form.

^ I was skeptical, and actually had to check this one out, and depending on who you ask, there were answers that the eyes don't grow and others that had them growing until the teens and still one or two others that had the eyeball growing an additional 40%, so I don't know that I totally know the right answer here. This is surely not for all creatures, because I've seen tadpoles that are smaller or at least the same size as an adult frog's eye. I have to imagine Marty Feldman's eyes grew (look him up)!

KOLDWARKID62 - Perhaps GMAN2887 is referring to humans? If I am not mistaken (and I very well could be) human eyes remain roughly the same size from the moment of birth all the way to adulthood. If that is the case, then it would be further substantiated by the fact that the creators stated that they wanted Godzilla's eyes to be very similar to a human's. I seem to remember reading that at some point in the past. Regardless, these are only my thoughts on the topic. Nothing more. :)

KoldWarKid,
Something Real is correct. The growth of the human eyeball is minimal--roughly the same size as when we're born.
I'm not privy to animal biology, but considering Anno has said Shin Godzilla's eye was modeled after a human's it would make sense that this would be the same case.

So to answer your initial question: The correct biology books. :)

Something Real - When I looked it up, it did refer only to human eyes.

I was initially thinking animals, and I'm like "No way", but when I looked it up, the articles referenced humans (didn't know Anno was basing off human eyes), so I will defer to the majority, and stand humbly corrected. ;)

KOLDWARKID62 -  I also discovered a great deal of conflicting information when I searched! Regardless, the information concerning Marty Feldman was incredible! :)

KOLDWARKID62 - Your gracious attitude is a model by which we should all strive to conduct ourselves. :)

@Something Real - Glad you liked the Marty Feldman thing and hope it gave you a chuckle! Happy Friday, btw!

KOLDWARKID62 - The very same to you! :)

i like how they both really resembles animals like how form one looks like a frilled shark and the second one looks like a squid