Sperm in mice team up to form clusters to enter the oviduct. Scientists found that when the number of sperm is reduced or if specific proteins are missing, these clusters don't form properly, leading to mating challenges. Even though the Tex101 protein-deficient sperm have normal traits, they struggle to create clusters and pass through the junction to reach the oviduct. Interestingly, having normal sperm around doesn't help the Tex101-deficient sperm improve their chances of passage. This teamwork among sperm clusters seems crucial for male fertility, shedding light on potential reasons for male infertility observed in humans.