Global Drosophila

melanogaster Research: a

bibliometric analysis Michán, L; Castañeda-Sortibrán,

A; Rodríguez-Arnaiz, R; Ayala,

FJ Drosophila Information Service, Vol. 93

(2010), 232-243.

Complementary material1

http://www.ou.edu/journals/dis/DIS93/Michan%20232.pdf

Abstract

• We investigate the scientific productivity of Drosophila-related research among

researchers, countries, institutions, journals, and subject areas, by a bibliometric

analysis of Drosophila research from 1900 to 2008. We have searched the Science

Citation Index (SCI) documents with the word Drosophila in the title. 48,981

documents were obtained from SCI 76.9% of the documents are research papers,

mostly (95.2%) written in English, and (55.8%) produced in the United States. The

study includes 4,600 institutions and 45,415 author names. Most prolific are 34

authors, who account for 9% of the articles published, with more than 100 research

papers produced by each author. We also provide a list of the 50 most cited articles.

We considered 1,648 journals; 60 of them (3.6%) published 66% of the articles.

Genetics is the main journal most used for Drosophila research publications (9.9%).

Genetics and heredity as well as biochemistry, molecular biology, and cell biology are

the dominant research subjects. We compare research in Drosophila with 10 other

organisms, frequently used as biological models: Escherichia, Saccharomyces,

Arabidopsis, Zea, Neurospora, Dictyostelium, Chlamydomonas, Caenorhabditis,

Schizosaccharomyces, and Danio. Escherichia coli is the most extensively used

model organism for genetics research since 1950, with 94,873 documents. We

analyzed 36,486 documents in detail with respect to their contents, using the indexing

keywords listed in the medical subject headings (MeSH) thesaurus.

2

Materials and methods

• Our search covered papers published during 1900-2008. The search was performed using the

Science Citation Index (SCI) and the PubMed database. SCI was started by the Institute for

Scientific Information (ISI) in 1963. It is now owned by Thomson Reuters and is available online

through the Web of Science database. PubMed Central, which started in 2000, includes articles

and peer-reviewed manuscripts dating back to mid the 1800s or early 1900s for some journals.

These databases include many journals; provide a citation index; and the results of the queries

are comparative concerning mainstream papers in scientific research. PubMed has detailed

document identification by the keywords listed in the medical subject headings (MeSH) thesaurus.

We accessed the Science Citation Index until 2008, in order to find out where research in

Drosophila has been done. We accessed data on documents with the word Drosophila in the title

of the paper, because we were interested only in documents with their main interest in Drosophila.

All records were retrieved for each database and were systematized in a database; then the data

sets were validated and normalized, and a quantitative analysis for each category was done:

document, author, affiliation institution, country, journal, subject area (from Science Citation Index)

and MeSH headings and subheadings (from PubMed). The 50 and the 10 most cited papers from

Science Citation Index were identified. Journals were processed by subject (sensu SCI), Impact

Factors were obtained from Journal Citation Report 2008 and core journals were identified with

Bradford`s method (Bradford, 1948). The same method was used for each of ten additional

biological models: Escherichia, Saccharomyces, Arabidopsis, Zea, Neurospora, Dictyostelium,

Chlamydomonas, Caenorhabditis, Schizosaccharomyces, and Danio. All the information was

organized with scientific, historical, and sociological points of view.

3

Results

• Papers. The total number of publications with Drosophila in the title

was 48,981 in the Science Citation Index and 36,486 in PubMed

(Figure 1). The first paper registered was published in 1905 by F.W.

Carpenter . Document type and language according to the Science

Citation Index are shown in Figures 2 and 3. The temporal trends of

publication in Drosophila, as well as in ten other biological models

are shown in Figures 4 and 5. There are 139 different subject

categories in the SCI, the 16 most frequent, each with more than 1%

of the total are shown in Figure 6. The temporal trends for the nine

most frequent subjects are shown in Figures 7 and 8. Information

about documents extracted from PubMed is in Figures 9 and 10.

4

Figure 1

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PubMed

y= 1,704e0,070x

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y = 4,072e0,065x

Figure 2

77%15%3%

3% 1% 1% 0%

Document type

Article Meeting Abstract Review

Note Proceedings Paper Letter

Editorial Material

Figure 3

English95.15%

Russsian2.29%

Japanese1.35%

French0.89% German

0.32%

Language

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Zea (7636)

Neurospora (6640)

Dictyostelium (6191)

Chlamydomonas (5646)

Schizosaccharomyces (3183)

Danio (973)

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Escherichia (94873)

Drosophila (48989)

Saccharomyces (27549)

Arabidopsis (18094)

Caenorhabditis (5353)

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Figure 6

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12581258 1231 1200 782 706

10907

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2519 2482 2365 23401811

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(2)(1)

(20)

(3)

(15)

(18)

(6)

(3)(2)

Figure 7

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Genetics & Heredity

Biochemistry & Molecular Biology

Cell Biology

Developmental Biology

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• Researchers. We found 45,415 author names. The 34

most prolific, each with more than 100 published articles

and jointly accounting for 9% of all the papers, are

shown in Table 1. There were 119 affiliation countries, 32

(2.6%) of which include each more than 100 papers, and

jointly accounting for 97% of all papers. The 10 countries

with most publications are shown in Figure 11. The

United States was the country most represented. There

were 4,600 different institutions, such as universities,

departments, and corporations. The 18 most highly

represented are shown in Figure 12. Table 2 lists the 50

papers with the highest citation impact.

12

13

Researcher Documents

(48,981)

Rubin, GM 220 (5)

David, JR 203

Dobzhansky, T 185

Perrimon, N 184

Hall, JC 170

Mukai, T 164

Zhimulev, IF 160

Jan, YN 155

Gehring, WJ 149 (2)

Jackle, H 148

Ayala, FJ 143 (1)

Hoffman, AA 139 (1)

Jan, LY 131

Bownes, M 126

Parsons, PA 126

Partridge, L 126

Ashburner, M 123 (2)

Green, MM 122

Belyaeva, ES 122

Glover, DM 119

Levine, M 115 (1)

Mahowald, AP 115

King, RC 111

Singh, BN 111

, SCR 110

Wurgler, FE 110

Korochkin, LI 109

Hartl, DL 109

Georgiev, PG 106

Kaufman, TC 103

Wu, CF 103 (1)

Rosbash, M 101

Ehrman, L 101

Mackay, TFC 101

Table 1. The 34 most prolific researchers in Drosophila, each with 100 or more papers, as

retrieved from the Web of Science. Numbers in parentheses are documents shown in Table 2.

Figure 8

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Evolutionary Biology

Ecology

Zoology

Toxicology

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Figure 9

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Dro

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Dro

sophila

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Mutatio

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ts31837

18425

14984

96148548

79316838

5319 50494184 3517 3381 3358 3309

10201

26262654268727782832

Figure10

0%

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70%

Gen

etics

Metab

olism

Ph

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log

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bry

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& d

evelo

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23265

13586

11655

46854177

37123414 3246 2931 2859 2574 2361

1524 1408

6843

11631201

Figure 11

55.8%

7.4%

7.2%

6.4%

6.2%

4.0%4.0%

3.5%2.9% 2.7%

USA France

England Japan

Germany Canada

Spain Switzerland

USSR Australia

Figure 18

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Aca S

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, Fran

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Institution

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19

Adams et al. (2000). The genome sequence of Drosophila melanogaster. Science, 287(5460):2185–2195. 2,751

Rubin, G. M. and Spradling, A. C. (1982). Genetic-transformation of Drosophila with transposable element vectors. Science, 218(4570):348–353. 2,184

Tautz, D. and Pfeifle, C. (1989). A non-radioactive in situ hybridization method for the localization of specific RNAs in Drosophila embryos reveals translational control of the segmentation gene hunchback. Chromosoma, 98(2):81–85. 2,126

Lewis, E. B. (1978). Gene complex controlling segmentation in Drosophila. Nature, 276(5688):565–570. 1,906

Medzhitov et al. (1997). A human homologue of the Drosophila toll protein signals activation of adaptive immunity. Nature, 388(6640):394–397. 1,752

Nüsslein-Volhard, C. and Wieschaus, E. (1980). Mutations affecting segment number and polarity in Drosophila. Nature, 287(5785):795–801. 1,727

Lemaitre et al. (1996). The dorsoventral regulatory gene cassette spatzle/toll/cactus controls the potent antifungal response in Drosophila adults. Cell, 86(6):973–983. 1,277

Spradling, A. C. and Rubin, G. M. (1982). Transposition of cloned p elements into Drosophila germ line chromosomes. Science, 218(4570):341–347. 1,228

Robertson et al. (1988). A stable genomic source of p-element transposase in Drosophila melanogaster. Genetics, 118(3):460–470. 1,153

Hammond et al. (2000). An RNA-directed nuclease mediates post-transcriptional gene silencing in Drosophila cells. Nature, 404(6775):293–296. 1,147

Ashburner, M. and Bonner, J. J. (1979). Induction of gene activity in Drosophila by heat shock. Cell, 17(2):241–254. 1,135

McDonald, J. H. and Kreitman, M. (1991). Adaptive protein evolution at the adh locus in Drosophila. Nature, 351(6328):652–654. 1,117

Xu, T. and Rubin, G. M. (1993). Analysis of genetic mosaics in developing and adult Drosophila tissues. Development, 117(4):1223–1237. 1,091

Bateman, A. J. (1948). Intra-sexual selection in Drosophila. Heredity, 2(3):349–368. 1,079

Ephrussi, B. and Beadle, G. W. (1936). A technique of transplantation for Drosophila. American Naturalist, 70:218–225. 942

Clary, D. O. and Wolstenholme, D. R. (1985). The mitochondrial-DNA molecule of Drosophila yakuba - nucleotide-sequence, gene organization, and genetic-code. Journal of Molecular Evolution, 22(3):252–271. 930

Konopka, R. J. and Benzer, S. (1971). Clock mutants of Drosophila melanogaster. Proceedings of the of Sciences of the , 68(9):2112–2116. 902

Ayala et al. (1972). Enzyme variability in the Drosophila willistoni group. IV. Genic variation in natural populations of Drosophila willistoni. Genetics, 70(1):113–139. 900

Ellisen et al. (1991). Tan-1, the human homolog of the Drosophila notch gene, is broken by chromosomal translocations in t-lymphoblastic neoplasms. Cell, 66(4):649–660. 894

Wu, C. (1980). The 5’ ends of Drosophila heat-shock genes in chromatin are hypersensitive to DNase-i. Nature, 286(5776):854–860. 872

Rock et al. (1998). A family of human receptors structurally related to Drosophila toll. Proceedings of the of Sciences of the , 95(2):588–593. 860

Giot et al. (2003). A protein interaction map of Drosophila melanogaster. Science, 302(5651):1727–1736. 853

Cavener, D. R. (1987). Comparison of the consensus sequence flanking translational start sites in Drosophila and vertebrates. Nucleic Acids Research, 15(4):1353–1360. 845

Orr, W. C. and Sohal, R. S. (1994). Extension of life-span by overexpression of superoxide-dismutase and catalase in Drosophila melanogaster. Science, 263(5150):1128–1130. 838

Ingham, P. W. (1988). The molecular-genetics of embryonic pattern-formation in Drosophila. Nature, 335(6085):25–34. 837

Akam, M. (1987). The molecular-basis for metameric pattern in the Drosophila embryo. Development, 101(1):1–22. 834

Stjohnston, D. and Nüsslein-Volhard, C. (1992). The origin of pattern and polarity in the Drosophila embryo. Cell, 68(2):201–219. 831

Ritossa, F. (1962). New puffing pattern induced by temperature shock and dnp in Drosophila. Experientia, 18(12):571–573. 829

Pelham, H. R. B. (1982). A regulatory upstream promoter element in the Drosophila hsp 70 heat-shock gene. Cell, 30(2):517–528. 807

Hahn et al. (1996). Mutations of the human homolog of Drosophila patched in the nevoid basal cell carcinoma syndrome. Cell, 85(6):841–851. 800

Lewontin, R. C. and Hubby, J. L. (1966). A molecular approach to study of genic heterozygosity in natural populations. II. Amount of variation and degree of heterozygosity in natural populations of Drosophila pseudoobscura. Genetics, 54(2):595–609. 796

(1972). Cell lines derived from late embryonic stages of Drosophila melanogaster. Journal of Embryology and Experimental Morphology, 27(APR):353–&. 785

Bhanot et al. (1996). A new member of the frizzled family from Drosophila functions as a wingless receptor. Nature, 382(6588):225–230. 758

McGinnis et al. (1984). A conserved DNA-sequence in homoeotic genes of the Drosophila Antennapedia and bithorax complexes. Nature, 308(5958):428–433. 756

Halder, G., Callaerts, P., and Gehring, W. J. (1995). Induction of ectopic eyes by targeted expression of the eyeless gene in Drosophila. Science, 267(5205):1788–1792. 737

Feany, M. B. and Bender, W. W. (2000). A Drosophila model of Parkinson’s disease. Nature, 404(6776):394–398. 729

Krauss, S., Concordet, J. P., and Ingham, P. W. (1993). A functionally conserved homology of the Drosophila segment polarity gene-hh is expressed in tissues with polarizing activity in zebrafish embryos. Cell, 75(7):1431–1444. 723

Cho, K. O., Hunt, C. A., and Kennedy, M. B. (1992). The rat-brain postsynaptic density fraction contains a homolog of the Drosophila disks-large tumor suppressor protein. Neuron, 9(5):929–942. 721

Graham, A., Papalopulu, N., and Krumlauf, R. (1989). The murine and Drosophila homeobox gene complexes have common features of organization and expression. Cell, 57(3):367–378. 719

Tkachuk, D. C., Kohler, S., and Cleary, M. L. (1992). Involvement of a homolog of Drosophila-trithorax by 11q23 chromosomal translocations in acute leukemias. Cell, 71(4):691–700. 714

Poole et al. (1985). The engrailed locus of Drosophila: structural analysis of an embryonic transcript. Cell, 40(1):37–43. 705

Ohare, K. and Rubin, G. M. (1983). Structures of p-transposable elements and their sites of insertion and excision in the Drosophila melanogaster genome. Cell, 34(1):25–35. 700

Vandewetering et al. (1997). Armadillo co-activates transcription driven by the product of the Drosophila segment polarity gene dtcf. Cell, 88(6):789–799. 695

Gu et al. (1992). The t(4-11) chromosome-translocation of human acute leukemias fuses the all-1 gene, related to Drosophila-trithorax, to the af-4 gene. Cell, 71(4):701–708. 694

Tissiere, A., Mitchell, H. K., and Tracy, U. M. (1974). Protein-synthesis in salivary-glands of Drosophila melanogaster: Relation to chromosome puffs. Journal of Molecular Biology, 84(3):389–398. 671

Ingolia, T. D. and Craig, E. A. (1982). Four small Drosophila heat-shock proteins are related to each other and to mammalian alpha-crystallin. Proceedings of the of Sciences of the United States of America-Biological Sciences, 79(7):2360–2364. 651

Smith, D. E. and Fisher, P. A. (1984). Identification, developmental regulation, and response to heat-shock of 2 antigenically related forms of a major nuclear-envelope protein in Drosophila embryos: application of an improved method for affinity

purification of antibodies using polypeptides immobilized on nitrocellulose blots. Journal of Cell Biology, 99(1):20–28.

647

Elbashir et al. (2001). Functional anatomy of si RNAs for mediating efficient RNAi in Drosophila melanogaster embryo lysate. Embo Journal, 20(23):6877–6888. 641

Padgett, R. W., Stjohnston, R. D., and Gelbart, W. M. (1987). A transcript from a Drosophila pattern gene predicts a protein homologous to the transforming growth-factor-beta family. Nature, 325(6099):81–84. 639

Garcia-Bellido, A., Ripoll, P., and Morata, G. (1973). Developmental compartmentalization of wing disk of Drosophila. Nature-New Biology, 245(147):251–253. 636

Table 2. The 50 most cited papers according to Science Citation Index.

• Journals. A total of 1,648 journal names were obtained, 60 of them (3.6%)

published 66.6% of the articles about Drosophila (Table 3). Genetics has the

most publications, with 10% of the total. Cell and Nature have the highest

impact (Figure 13).

• The 34 authors, each with more than 100 Drosophila research papers,

jointly produced almost 10% of all published papers and are the authors of

13 (26%) of the 50 most cited papers. 55.8% of all the papers had at least

one North American author. After the United States and France, the most

productive countries were England, Japan, and Germany. Jointly, these 5

countries account for 65% of the publications (Figure 11). The most

productive institutions are the Russian Academy of Sciences, the Centre

National de la Recherche Scientifique (CNRS in France), and Harvard

University, each with more than 1,000 publications. Harvard had 5 (10%) of

the most cited documents (Figure 12).

20

Figure 13

0%

2%

4%

6%

8%

10%

12%

Gen

etics

Dev

elop

men

t

Dev

el Bio

l

PN

AS

Japan

J Gen

etics

Natu

re

Mutatio

n R

esearch

Cell

Mol B

io C

ell

Gen

etika

J Bio

Ch

emistry

Evo

lutio

n

J Cell B

iol

Gen

etica

Em

bo

J

Do

cum

ents

4860

17651689

1039891 843 837 784 731 699 693 660 649 605

1528

(4%)

(6%)

(22%)(26%)

(2%)(2%)

(6%)

[9.380][4.416]

[6.812]

[4.002]

[9.120][4.737][5.520][5.558][31.253][3.198]*

[31.434]

[8.295][1.980]

22Table 3. Core journals (60, with 66.6% of all published papers) of Drosophila research.

Source Title Documents %

Genetics 4.860 9.92%

Development 1.765 3.60%

Developmental Biology 1.689 3.45%

PNAS 1.528 3.12%

Japanese Journal of Genetics 1.039 2.12%

Nature 891 1.82%

Mutation Research 843 1.72%

Cell 837 1.71%

Molecular Biology of The Cell 784 1.60%

Genetika 731 1.49%

Journal of Biological Chemistry 699 1.43%

Evolution 693 1.41%

Journal Cell Biology 660 1.35%

Genetica 649 1.33%

Embo Journal 605 1.24%

Chromosoma 592 1.21%

Heredity 588 1.20%

Genes & Development 585 1.19%

Mechanisms of Development 569 1.16%

Molecular and Cellular Biology 544 1.11%

Science 514 1.05%

Nucleic Acids Research 497 1.01%

Current Biology 491 1.00%

American Naturalist 463 0.95%

Genetical Research 446 0.91%

Molecular & General Genetics 442 0.90%

Experientia 436 0.89%

Journal of Neurogenetics 430 0.88%

Hereditas 390 0.80%

Journal of Insect Physiology 387 0.79%

Journal of Neuroscience 368 0.75%

Biochemical Genetics 356 0.73%

Gene 340 0.69%

Journal of Cell Science 317 0.65%

Molecular Biology And Evolution 317 0.65%

Behavior Genetics 312 0.64%

Neuron 300 0.60%

Journal of Experimental Zoology 270 0.55%

Journal of Molecular Biology 252 0.51%

Journal of Cellular Biochemistry 243 0.50%

American Zoologist 236 0.48%

FEBS Letters 234 0.48%

Biochemical And Biophysical Research Communications 233 0.48%

Journal of Heredity 214 0.44%

FASEB Journal 209 0.43%

Journal of Genetics 207 0.42%

Russian Journal of Genetics 202 0.41%

Developmental Genetics 194 0.40%

Developmental Cell 192 0.39%

European Journal of Cell Biology 192 0.39%

Journal of Molecular Evolution 192 0.39%

Canadian Journal of Genetics and Cytology 191 0.39%

Biophysical Journal 189 0.39%

Doklady Akademii Nauk SSSR 185 0.38%

Journal of Experimental Biology 184 0.38%

Journal of Neurobiology 176 0.36%

Development Genes and Evolution 167 0.34%

Insect Biochemistry and Molecular Biology 166 0.34%

Wilhelm Roux’s Archives of Developmental Biology 166 0.34%

Animal Behaviour 164 0.33%

Discussion• We have analyzed 48,981 documents in the Science Citation Index (Figure 1), mostly articles

(nearly 77%) (Figure 2), the majority written in English (95%) (Figure 3).

• Temporal scientific production in Drosophila research is fairly similar (and with similar

exponential growth in both SCI and PubMed. There is a continuous increase from 1950 to 2007,

with a decrease in 2008 (Figure 1). This decrease may only be apparent and reflect a usual

delay in the indexation process. The comparison with other biological models is interesting: Zea

and Chlamydomonas show a reasonably stable publication trend (after 1970). From

approximately 1980 on, Arabidopsis and Caenorhabditis exhibit exponential growth, while

Neurospora and Dictyostelium decrease. Escherichia is the most extensively used model

organism for genetics research; from 1950 till 2007, nearly twice as many articles are published

as for Drosophila.

• One factor contributing to the extensive research with Drosophila may have been the free flow

of materials and ideas among its researchers [79]. Morgan's style of research and leadership

was distinctively focused on an experimental, rather than a descriptive approach to science.

Between 1940 and 1970 new techniques were developed, mutants increased in number and

complexity, all fairly freely shared by a gradually increasing number of investigators.

• In the 1970s and 1980s, genetics, developmental, and molecular biology came together in a

successful combination, which brought Drosophila research to a climax. Molecular biology rose

later than the other subjects, associated mostly with the ability to manipulate DNA and RNA, so

that researchers could work with individual genes that produced phenotypic alterations. E.B.

Lewis [80] studied mutations which caused bizarre transformations of the body plan: mutations

in genes in the 'bithorax complex' led to flies with two sets of wings or legs on abdominal

segments. The strangeness of the changes produced became a clue to discover the crucial role

of master control genes that program the final body plan of the organism. 23

• Christiane Nüsslein-Volhard and Eric Wieschaus (1980) [81] began working together with Drosophila

flies in a laboratory in Heidelberg, Germany. They systematically searched for mutant genes that

affect the formation of segments in the fly embryo. They identified a series of new genes that drive the

early development of the organism, and also were able to classify the genes into functional groups.

They showed that these genes are conserved in vertebrates. It would soon become clear that close

relatives of these genes, performing similar roles, exist in many other different organisms, including

humans. Indeed, it is now thought that more than 60 percent of the genes involved in human diseases

may have counterparts in the fly.

• An important breakthrough for manipulating the genome was made in 1982 by A.C. Spradling and

G.M. Rubin [82]. They developed a method for making transgenic flies by means of transposable

element vectors. They used this method to achieve the first rescue of a mutant phenotype in an

animal by gene transfer.

• New technologies are also being brought to bear on the study of Drosophila. Since 1999, the genome

sequence of Drosophila has been available, and researchers are using functional genomics to

investigate global patterns of gene and protein expression. The genome sequences of several other

Drosophila species have now become available, which opens up new opportunities for functional

genomics studies, looking at gene and protein expression on a large scale. Such experiments can

produce huge amounts of data, difficult to interpret, organize, and store.

• As pointed out, genetics and heredity, biochemistry, molecular biology and cell biology are the leading

research subjects in SCI. Some journals in our survey are multidisciplinary, such as Nature and

Science. We have shown that there are temporal trends with respect to research subject as well as to

model organisms and prevailing methodologies: toxicology, cell biology, and descriptive

developmental research are decreasing, while evolutionary biology, biochemistry, and molecular

biology are increasing. The most frequent terms in Drosophila research have genetics, heredity, or a

molecular connotation.

• The most cited paper, providing the complete sequence of the euchromatic region of the Drosophila

genome was published in Science in 2000, with 2,751 citations at the time of our survey.24

Figure Legends

• Figure 1. Temporal trend in global Drosophila publications, 1905-2008 (from WoS

and PubMed).

• Figure 2. Document type in Drosophila research according to the Science Citation

Index.

• Figure 3. Document language in Drosophila research according to the Science

Citation Index.

• Figure 4. Temporal trend and total number of publications in Drosophila and four

other biological models.

• Figure 5. Temporal trend and total number of publications in five biological models.

• Figure 6. The 16 most frequent subjects and number of documents (% most cited

papers).

• Figure 7. Temporal trends of Drosophila research for the most frequent subject.

• Figure 8. Temporal trends of Drosophila research for four additional subjects.

• Figure 9. Most frequent MeSH headings from PubMed: number and percent of

documents.

• Figure 10. Most frequent MeSH subjects from PubMed: numbered percent of

documents.

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