On Citations and Scientific Research in Ecology

Begin with a few common assumptions in science.
(1) Higher citation rates define more valuable science
(2) Recent references are more valuable than older references
(3) Retracted scientific research is rapidly recognized and dropped from discussion
(4) The vast majority of scientific research reported in papers is read by other scientists.
(5) Results cited in scientific papers are cited correctly in subsequent references.

The number of publications in ecological science is growing rapidly world-wide, and a corollary of this must be that the total number of citations is growing even more rapidly (e.g. Westgate et al. 2020). It is well recognized that citations are unevenly spread among published papers, and reports that nearly 50% of published papers never receive any citations at all are commonly cited. I have not been able to validate this for papers in the ecological sciences. The more important question is whether the most highly cited papers are the most significant for progress in ecological understanding. If this is the case, you can simply ignore the vast majority of the published literature and save reading time. But this seems unlikely to be correct for ecological science.

The issue of scientific importance is a time bomb partly because ‘importance’ may be redefined over time as sciences mature, and this redefinition may occur in years or tens of years. A classic example is the citation history of Charles Elton’s (1958) book on invasions (Richardson and Pyšek 2008). Published in 1958, this book had almost no citations until the 1990s. Citations have become more and more important in the ranking of individual scholars as well as university departments during the last 20 years (Keville et al. 2017). This has occurred despite continuous warnings that citations are not valid for comparing individuals of different age or departments in different academic fields (Patience et al. 2017). If you publish in Covid-19 research this year, you are likely to get more citations than the person working in earthworm taxonomy.

Most published papers confirm the general belief that citing the most recent papers is more successful than citing older papers. If this belief could be tested, it would simplify education of graduate students and facilitate teaching. But the simple fact is that in ecology often (but not always) older papers have better perspectives than more recent papers or indicate paths of research that have failed to lead to ecological wisdom. 

Newspapers revel in stories of retracted research, if only to show that scientists are human. Of some interest are studies that show that research which is retracted continues to be cited. Hagberg (2020) cites a case in which a paper was retracted but continued to be cited as much after retraction as before. Fortunately, retracted research is rare in the ecological sciences but not absent, but the various conflicting ways in which scientific journals deal with papers with fraudulent results discovered after they are published leave much to be desired. 

A final comment on references is a warning to anyone reading the discussion or conclusions of a paper. Smith and Cumberledge (2020) have reported a random sample of references in a variety of scientific papers indicated a 25% error rate in ‘quotation’ errors. Quotation errors are distinct from ‘citation errors’ which are minor mistakes in the year of publication, page numbers or names in citations given in papers. Quotation errors are examples of “original paper authors say XX, citing paper says YY, a contradiction to what was originally reported. They used 250 citations from the 5 most highly cited scientific publications of today to determine how many papers contained ‘quotation errors’ and found a 25% error rate. About 33% of these errors could be called ‘Unsubstantiated’ and about 50% of the remaining quotation errors were ‘Impossible to substantiate” category. Their study reinforced early work by Todd et al. (2007) and pointed out to readers a weakness in the current use of references in scientific writing that is often missed by reviewers.

On a more positive note, on how to increase your citation rate, Murphy et al. (2019) surveyed the titles of 3562 papers and their subsequent citation rate from four ecology and entomology journals. They found that papers that did not include the Latin name of species in the title of the paper were cited 47% more often than papers with Latin names in the title. The number of words in the title of the paper had almost no effect on citation rates. They were unable to determine whether the injection of humor in the title of the paper had any effect on citation rates because too few papers attempted humor in the title.   

Elton, C.S. (1958) ‘The Ecology of Invasions by Animals and Plants.’ (Methuen: London.) ISBN: 978-3-030-34721-5

Hagberg, J.M. (2020). The unfortunately long life of some retracted biomedical research publications. Journal of Applied Physiology 128, 1381-1391. doi: 10.1152/japplphysiol.00003.2020.

Keville, M.P., Nelson, C.R., and Hauer, F.R. (2017). Academic productivity in the field of ecology. Ecosphere 8, e01620. doi: 10.1002/ecs2.1620.

Murphy, S.M., Vidal, M.C., Hallagan, C.J., Broder, E.D., and Barnes, E.E. (2019). Does this title bug (Hemiptera) you? How to write a title that increases your citations. Ecological Entomology 44, 593-600. doi: 10.1111/een.12740.

Patience, G.S., Patience, C.A., Blais, B., and Bertrand, F. (2017). Citation analysis of scientific categories. Heliyon 3, e00300. doi: https://doi.org/10.1016/j.heliyon.2017.e00300.

Richardson, D.M. and Pyšek, P. (2008). Fifty years of invasion ecology – the legacy of Charles Elton. Diversity and Distributions 14, 161-168. doi: 10.1111/j.1472-4642.2007.00464.x.

Smith, N. and Cumberledge, A. (2020). Quotation errors in general science journals. Proceedings of the Royal Society. A, 476, 20200538. doi: 10.1098/rspa.2020.0538.

Todd, P.A., Yeo, D.C.J., Li, D., and Ladle, R.J. (2007). Citing practices in ecology: can we believe our own words? Oikos 116, 1599-1601. doi: 10.1111/j.2007.0030-1299.15992.x

Westgate, M.J., Barton, P.S., Lindenmayer, D.B., and Andrew., N.R. (2020). Quantifying shifts in topic popularity over 44 years of Austral Ecology. Austral Ecology 45, 663-671. doi: 10.1111/aec.12938.