Two benefits that female mammals provide their young by them is building a bond between mother and offspring and providing antibodies.

Your statement highlights two crucial benefits that female mammals provide to their young: the establishment of a mother-offspring bond and the provision of antibodies through nursing.

1. Building a Bond: The bond between mother and offspring is essential for the emotional and social development of the young. This bond fosters attachment, which is vital for the survival of the offspring, as it encourages the mother to protect and care for her young. The nurturing behavior exhibited by the mother helps in forming profound emotional ties that can influence future social relationships.

2. Providing Antibodies: Nursing provides young mammals with colostrum, which is the first milk produced after birth. Colostrum is rich in immunoglobulins, specifically IgA, which protects the young by providing passive immunity. This is particularly important as newborns have immature immune systems, and the antibodies from the mother help to safeguard them against infections and diseases during the early stages of life.

Overall, these benefits not only contribute to the immediate wellbeing of the young but also play significant roles in their long-term health and social development.