The Population Ecology of Technology: An Empirical Study of US Biotechnology Patents from 1976 to 2003

Abstract

A detailed understanding of technological change as an evolutionary process is currently not well understood. To increase our understanding, we build upon theory from organizational ecology to develop a model of endogenous technological growth and determine to what extent the pattern of technological growth can be attributed to the structural or systemic characteristics of the technology itself. Through an empirical investigation of patent data in the biotechnology industry from 1976 to 2003, we find that a technology's internal (i.e., density and diversity) ecological characteristics have a positive effect on its growth rate. The niche's external characteristics of crowding and status have a negative effect on its growth rate. Hence, applying theory from organizational ecology increases our understanding of technological change as an evolutionary process. We discuss the implications of our findings for the study of technological growth and evolution, and suggest avenues for further research.

Fig 1. Example: calculation of total, local, and global crowding.

Total crowding calculates the overlap in citations (of antecedent inventions) between our focal and all technological components. Local crowding calculates the overlap in citations between our focal and biotechnological (local) components only. Global crowding calculates the overlap in citations between our focal and all non-biotechnology (global) components.

Fig 2. Yearly entry rate of biotechnology patents.

The yearly entry rate of biotechnology patents shows a steady increase until 1998, after which we can witness a decline in the number of patents. This seems to indicate that biotechnology has entered into a different stage of technological development, in accordance with the S-shaped growth path commonly reported in technological development.

Fig 3. Locally weighted regression (lowess) of relative entry per niche.

While a clear decrease in the ‘average’ relative entry of patents in component niches cannot be observed in this figure, a decreasing growth rate in the relative entry rates (or leveling-off) can clearly be established, again in accordance with the S-shaped growth path of technological development.

Fig 4. Yearly entry in clustered component niches.

As we can learn from Table 3, the major components are in groups 1 to 3, which display a common pattern. Groups 1 to 3 all peak between 1998 and 2000, and the main different between these groups of components is what occurs after this peak. The growth of the components in group 1 declines, whereas the growth of components in groups 2 and 3 first declines but then picks up again. Groups 4 to 6 show a rather erratic entry rate. The reason for the difference in growth patterns of individual components is that they are located differently along the technological lifecycle. Some are in the beginning of their development while others seem to be more fully developed.