Scientists have established that men and women think differently and reach decisions differently. They tend to have different interests and aptitudes. These distinctions go well beyond hair styles, dress, or anatomical differences--and reach the core of being, of what makes a person who he or she is.
Jesus made clear that marriage will no longer exist in heaven or the new earth.
But they which shall be accounted worthy to obtain that world, and the resurrection from the dead, neither marry, nor are given in marriage: Neither can they die any more: for they are equal unto the angels; and are the children of God, being the children of the resurrection. (Luke 20:35-36, KJV)
Accepting that sexuality will no longer exist, with its anatomical distinctions, is there any further clue in Jesus' teaching that gender differences themselves might also be erased?
The Bible seems to indicate that we will know each other in heaven, even as we are known here.
For now we see through a glass, darkly; but then face to face: now I know in part; but then shall I know even as also I am known. (1 Corinthians 13:12, KJV)
Will we know men by their short hair, women by their long hair? Will our masculine or feminine personalities be preserved? Will we still be men and women in heaven, even though we are no longer sexual beings, and will no longer be in marriage relationships?
NOTE: A related, but different, question is here.