The Intertwined Rise of Collaboration Scale, Reference Diversity, and Breakthrough Potential in Modern Science: A 40-Year Cross-Disciplinary Study

Over the last four decades, the way knowledge is created in academia has transformed dramatically: research teams have grown larger, scholars draw from ever-wider pools of prior work, and the most influential discoveries increasingly emerge from complex collaborative efforts. Using a massive dataset of over 15 million publications spanning 1970-2010 and covering six major domains (Humanities, Social Sciences, Agricultural Sciences, Medical and Health Sciences, Engineering and Technology, and Natural Sciences), this study tracks how three core features of scientific papers - authorship team size, the breadth and variety of cited sources, and eventual citation impact - have co-evolved over time. We uncover striking differences across disciplines. In every field, papers that build on a broader and more diverse knowledge base consistently attract more citations later on, lending large-scale empirical support to theories that view scientific breakthroughs as outcomes of novel recombination across distant ideas. Bigger teams, on average, generate work with greater ultimate influence, but the gains taper off after a certain scale; very large consortia seldom produce the absolute highest-impact papers. While the Humanities and Social Sciences remain anchored in solo or small-group authorship traditions, the Natural Sciences, Medicine, and Engineering have moved decisively toward big-team mega-science. These patterns illuminate the underlying production technology of discovery, reveal discipline-specific barriers to collaboration and idea integration, and offer evidence-based guidance for research funding agencies, universities, and policymakers seeking to organize scientific work for maximum breakthrough potential.