Answer: Humans have speech while animals don't because animals were not doted with the privilege. In a religious point of view God created animals for our enjoyment, so they would prosper and be happy. However, nowadays its difficult for animals to be happy. Chapter one of the book, "Knowledge that leads to everlasting life" states: "The tender embrace of a wanted person, joyful smiles during a good meal in company of good friends... Moments like these make us happy... God's will is that you remain indefinitely joyous in optimum conditions and in a grand environment". Here what the book suggests is that God created human beings to remain in a beautiful paradise. Genesis 1: 1 states: " In the beginning God created the heavens and the Earth", Genesis 2:9 say's: "Jehovah God made made grow out of the ground every tree that was pleasing to the eye". God made conditions that were enjoyable and the addition of animals made the experience much more enjoyable.
Explanation: We humans use our throat, chest, and mouths contracting the muscles of the ribcage and the diaphragm compresses the chest cavity and forces air out to the Rokia, then the rushing air passes through the larynx where it vibrates thin stretched membranes to produce the voice. Now, animals do not have the right structure inside the brains in order for them to speak or use a complex language. Also, the anatomy shows that the way their throats, mouths and lips are made do not allow them to form the right sounds needed for speech. However, they do use a various use of sounds to communicate with other animals.
