I didn't reach very far [in my own genealogy] but still working on it. I hope to reach back to Adam one day.
"The objective of family history work is to make the blessings of the temple available to all people, both living and dead. As we attend the temple and perform work for the dead, we accomplish a deep sense of alliance with God and a better understanding of his plan for the salvation of the human race. We learn to love our neighbors as ourselves. Truly there is no work equal to that done in the temple. "In addition to the blessings we receive from doing work for the dead, we receive personal blessings as we attend the temple."
(Howard W. Hunter, "We Have a Work to Do," Ensign, Mar. 1995, 65)
"Following His crucifixion, Jesus ministered in the spirit world, setting in motion missionary work among those who had died without hearing the gospel (See 1 Pet. 4-6; D&C 138:10-37). Baptism for these souls would logically be expected...."
"From the days of Adam to the meridian of time, temple ordinances were performed for the living only. Ordinances for the dead had to await the Atonement and postmortal ministry of the Savior (See D&C 138:18-37)."
(Russell M. Nelson, "The Spirit of Elijah," Ensign, Nov. 1994, 84-85)
"Now, brethren and sisters, I invite you to look beyond the narrow boundaries of your own wards and rise to the larger vision of this, the work of God. We have a challenge to meet, a work to do beyond the comprehension of any of us--that is, to assist our Heavenly Father to save His sons and daughters of all generations, both the living and the dead, to work for the salvation not only of those in the Church, but for those presently outside, wherever they may be. No body of people on the face of the earth has received a stronger mandate from the God of heaven than have we of this Church."
(Gordon B. Hinckley, "Rise to a Larger Vision of the Work," Ensign, May 1990, 97)