Sperm Teamwork Is Far More Common Than Scientists Realized

Key Points:

• A new study published in Nature Communications reveals that sperm cooperation, known as sperm conjugation, has evolved repeatedly over the past 500-600 million years across arthropods, including insects, spiders, crabs, and centipedes.
• Researchers mapped sperm traits onto an evolutionary tree, finding that sperm cooperation has emerged, disappeared, and reappeared multiple times, suggesting convergent evolution of this cooperative behavior in diverse groups.
• The study highlights the role of sperm-associated material (SAM), a membrane-bound substance that binds sperm together or organizes them into groups, which likely evolved initially to protect sperm and later facilitated conjugation.
• Understanding sperm cooperation challenges the traditional view of fertilization as purely competitive and may inform new approaches to human reproductive health and pest control, such as targeting the unusual sperm coatings of invasive spotted lanternflies.
• The research was conducted by biologists from Syracuse University and partner institutions, funded by the National Science Foundation and private donors.