[9급 지방직 영어 2013년 15번]

In other words, our behavior is neither wholly determined by our genes nor wholly free from them.

Grub's birth rekindled my interest in the nature vs. nurture debate, which was at that time producing bitter arguments in scientific circles. ( A ) Were we humans mainly the product of our genetic makeup or the product of our environment? ( B ) In recent years, these flames of controversy have died down, and it is now accepted that in all animals with reasonably complex brains, adult behavior is acquired through a mix of inherited traits and experience gained as the individual goes through life. ( C ) The more sophisticated an animal's brain, the greater the role that learning is likely to play in shaping its behavior, and the more variation we shall find between one individual and another. ( D ) And the information acquired and lessons learned during infancy and childhood, when behavior is at its most flexible, are likely to have particular significance.