In In re Baby Girl M. (1984) 37 Cal. 3d 65, the Court held that in a proceeding to terminate a natural father's parental rights, the general custody statute--including the detriment standard--applied; thus, a natural father's parental rights could not be terminated absent a finding that his custody would be detrimental to the child. There, the Supreme Court held that a natural father had been erroneously denied custody without a finding of detriment. (In re Baby Girl M., supra, 37 Cal. 3d at pp. 68-73.) It recognized that an unwed father's constitutional "'opportunity interest' " required "'commitment to and exercise of custodial responsibility' " and could be lost if he "voluntarily ignored his rights" or "failed to pursue possibilities available to him." It indicated, however, the natural father before it had maintained his opportunity interest. (Id., at pp. 73-75.)