english: But even though we know that these differences occur, 66 percent of the brain research that begins in animals is done in either male animals or animals in whom the sex is not identified.
non_english: Međutim, iako znamo da se ove razlike javljaju, 66 posto istraživanja mozga koja započinju na životinjama sprovodi se ili na mužjacima ili na životinjama čiji pol nije ustanovljen.