Few articles in history have had the disruptive impact of the 1953 article by James Watson and Francis Crick. Nature article proposing the double helix structure of DNA¹. It is a classic of small team science; two authors who propose a paradigm-changing idea that research teams around the world will continue to develop in the years to come.

But a new analysis of authorship data captured by the Nature Index over the past decade shows that small team science is in decline. In some fields of research, especially in the biological and health sciences, where Watson and Crick had their impact, single- or double-authored articles are increasingly rare.

Across the natural sciences, the proportion of articles in the index with one or two authors decreased from 10.8% to 7.1% between 2015 and 2024. During the same period, large team science grew rapidly, with the greatest publication growth seen in articles with between 11 and 50 authors. Overall, index publications with between 3 and 50 authors increased from 88.5% to 92.2%.

Although the Nature Index tracks only a subset of high-quality journals, the findings are consistent with previous studies showing a long-term increase in team size across science (see ‘Middle Ground’). At the beginning of the last century, for example, most articles were written by one or two scientists.². Since the mid-20th century, the average size of research teams has grown steadily in most scientific disciplines.³.

According to Lingfei Wu, an information scientist at the University of Pittsburgh in Pennsylvania, who studies the effect of factors such as team size on scientific innovation, “the decline in the number of one- and two-author papers is one of the most stable patterns in science.”

Team dynamics

Among the natural sciences subjects in the Nature Index, the life sciences had the lowest proportion of articles by small teams in 2024. Publications by one and two authors fell from 6.1% to 3.8% of life sciences articles between 2015 and 2024, while articles with 3 to 50 authors increased from 93.3% to 95.3%. Chemistry had the second lowest proportion of small equipment items in 2024, at 4.7% of total chemistry items, down from 8.2% in 2015.

In the health sciences, which have been included in the Nature Index since 2022, one- and two-author articles have stagnated at a rate of 1%.

The physical sciences are the only subject whose number of small equipment items increased in absolute terms (by just over 300 in the period 2015-24). However, they still fell as a proportion of total physical science articles (14.9% to 9.6%). This could reflect a trend where small team articles are still important to the topic, but large team articles are growing at a much faster rate.

The trend in the physical sciences could reflect a broader pattern evident in the index data: Although small-team science remains productive and, in some areas, has grown slightly in absolute terms, it is being eclipsed by the rapid expansion of research conducted by larger collaborations. As a result, small teams represent a decreasing proportion of scientific output, not because they are disappearing, but because large multi-author projects are becoming increasingly common and prolific (see ‘Team size by topic’).

Global change

According to Wu, the move away from small-team science is likely due to long-term changes in the way research is organized and conducted around the world. “After World War II, in the United States and then elsewhere, centralized funding agencies were established,” he says. “Forming research teams with combined expertise is a relatively easy way to apply for financial support.”

Today, funding systems often explicitly favor larger teams, says Chaoqun Ni, a metascience researcher at the University of Wisconsin-Madison. “In the United States, grants from the National Science Foundation and the National Institutes of Health encourage multicenter interdisciplinary teams.”

European Union grants also often stipulate cross-border collaboration, says Mike Thelwall, a data science researcher at the University of Sheffield, UK.

Nearly half of the world’s Natural Index chemical research is now done in China

In the analysis of the index, the decreasing proportion of articles by one and two authors is observed in most of the leading research countries. In the United States, these articles fell from 9.8% of the national total in 2015 to 6% in 2024. Germany, the United Kingdom, and South Korea experienced similar declines, with single- and two-author articles falling from around 7% to around 4% of their research output over the same period. China’s one- and two-author articles fell from 3.5% of its total output in 2015 to 2.4% in 2024.

Japan follows a different pattern. There, the proportion of one- and two-author articles remained stable at just under 8% over the 10-year period, and articles with between 3 and 50 authors decreased slightly, from 89.1% to 88.5% of the country’s total research output.

It is difficult to extrapolate this data to draw conclusions about broader research publication trends in specific countries. However, according to Yukie Sano, an information systems researcher at the University of Tsukuba in Japan, financial pressures and cultural factors have likely slowed the shift toward larger, especially international, research teams in the country. Compared to scientists in other countries, “Japanese researchers tend to have comparatively few international collaborators,” he says.

Sano attributes this in part to the weak yen, which has made overseas travel more expensive, and funding reforms that have shifted support from stable institutional funding to competitive grants. The result is a heavier administrative burden that leaves researchers with less time to build international networks.

“As I have had to spend more time writing funding proposals, my time for research has been reduced,” says Sano, who recently missed an international conference due to his workload. “I feel isolated from other countries because of the plight of Japanese universities.”

Although similar pressures affect researchers in other countries, the confluence of cultural and financial factors could explain the relative stability of the size of scientific teams in Japan in the analysis, Sano says.

specialized science

The complexity of modern science is another key factor in the decline of small team science. Scientists increasingly rely on large, expensive shared infrastructures, such as supercomputers, which requires large collaborations, Ni says.

Diverse knowledge is also required in many research projects. “Science is becoming much more specialized, and therefore in many fields, a good paper now requires the expertise of many people,” says Ni. For example, a biomedical study might require input from laboratory scientists, physicians, data analysts, and statisticians.