"Many Catholics hold what is known as 'moderate evolutionism,' that is, the theory that the human body evolved to a certain point from animals, and then God intervened directly and breathed into this living, animal body a human soul and so produced the first man and the first woman. Such a theory does not seem to be contrary to Catholic teaching, and Catholics are free to hold it."
Kenneth Baker, S.J., Fundamentals of Catholicism, 3 vols., San Francisco: Ignatius Press, 1982, II, p. 142.
"Thus, the Teaching of the Church leaves the doctrine of Evolution an
open question, as long as it confines its speculations to the development, from
other living matter already in existence, of the human body. (That souls are
immediately created by God is a view which the Catholic faith imposes on us.)
In the present state of scientific and theological opinion, this question may be
legitimately canvassed by research, and by discussion between experts on both
sides." [Encyclical of Pius XII, Humani generis, August, 1950, #36.]