If the defendant shall answer claiming any estate, interest in, or encumbrance upon the lands, he must, in his answer, specify and set forth the title, claim, interest, or encumbrance so claimed and, if not claimed in or upon the whole of such lands, he must specify and describe with sufficient certainty the part in, or upon which, the same is claimed and the manner in which, and the sources through which, such title, claim, interest, or encumbrance is claimed to be derived and created.
Ala. Code § 6-6-542 (1975)