The Catholic Church bases her teaching upon one source: The word of God. This divine revelation is transmitted in two ways: through Scripture and apostolic tradition. Many assume that only the writings of the apostles are the word of God. However, their oral transmission of the faith is also considered the word of God (1 Thess. 2:13). Few Protestant groups today accept the validity, let alone the authority, of tradition. In fact, many believe that Scripture is the only definitive source of divine truth.
The controversy surrounding evolution touches on our most central beliefs about ourselves and the world. Evolutionary theories have been used to answer questions about the origins of the universe, life, and man. These may be referred to as cosmological evolution, biological evolution, and human evolution. One’s opinion concerning one of these areas does not dictate what one believes concerning others.
~ Pope John XXII, in his Bull "Quorumdam exigit" (1317); urging a group of separatist friars who engaged in extreme asceticism to follow the Faith (e.g., Romans 13:1-2) and obey their leaders (from the article "Spirituals")