Around 7 million years ago, apes and humans were split off from a shared ancestor. During that time, our brains weren't much larger than an apes brain. Then about 4 millions years ago, something very interesting happened. A very small area of the human genome changed 70 times quicker than that of any other area, which resulted in drastic, significant changes in the cortex. The brain of the human tripled in size to its current weight of 1,300 grams (3 pounds). An apes brain today weighs between 300-500 grams, although their body size is very much the same of a humans.
FACT- In relation to our body size as a human, we are the biggest-brained animal. In relation to larger body animals though, sperm whales have the largest brain in the animal kingdom weighing between 15 and 20 pounds.
In conclusion, after learning of how similar an ape and humans brain are, along with their body type and features, how can someone say that we are not related in some way to the monkey/chimpanzee family?