- Adolfo Lutz Beitraege zur Kenntniss der brasilianischen Tabaniden. Rev. Soc. Sci. São Paulo 1: 19-32, published
- Raphaël Blanchard Les moustiques. Histoire naturelle et médicale Paris, F.R. de Rudeval, published.
- Adalbert Seitz , Gross-Schmetterlinge der Erde commenced. This vast work on Lepidoptera was published in German, English and French. It contained colour plates of all important species.
- William Lundbeck Diptera Danica. Genera and species of flies Hitherto found in Denmark commenced.
- Herbert Druce On Neotropical Lycaenidae, with Descriptions of New Species. Proceedings of the Zoological Society of London.
- Henry Christopher McCook Nature's Craftsmen: Popular Studies of Ants and Other Insects.
- Lajos Abafi Magyarország lepkéi (butterflies of Hungary)1907
- Edmund Reitter Fauna Germanica - Die Käfer des Deutschen Reichescommenced. This five volume masterwork remains in use today, almost 100 years from its inception.
- George Henry Verrall Stratiomyidae and succeeding families of the Diptera Brachycera of Great Britain- British flies published.
- Carlos Chagas observed the peculiar infestation of rural houses in Brazil with Triatoma, a "kissing" bug, later demonstrating that it was the vector of Trypanosoma cruzi, and he was able to prove experimentally that it could be transmitted to marmoset monkeys that were bitten by the infected bug. His description of the new disease was to become a classic in medicine and brought him domestic and international distinction.
- Charles Nicolle reasoned that it was most likely lice that were the vector for epidemic typhus.He tested his theory by infecting a chimpanzee with typhus, retrieving the lice from it, and placing it on a healthy chimpanzee. Within 10 days the second chimpanzee had typhus as well.
Antonio Berlese Volume I of Gli insetti loro organizzazione, sviluppo, abitudini e rapporti con l’uomo (Volume 2 1925).
- Friedrich Georg Hendel Die Arten der Platystominen. Abh. Zool.-Bot. Ges. Wien 8 (1): 1-409, 4 pls. published
- Filippo Silvestri Contribuzione alla conoscenza dei Termitidi e Termitofili dell'Africa occidentale. Bollettino del Laboratorio di Zoologia General e Agraria, Portici.
- Nathan Banks A Treatise on the Acarina, Or Mites the first comprehensive English handbook on mites.
- Günther Enderlein Über die phyletisch älteren Stratiomyiidensubfamilien (Xylophaginae, Chiromyzinae, Solvinae, Beridinae und Coenomyiinae). Mitt. Zool. Mus. Berl. 10: 150-214 published.
- Camillo Acqua Il bombice del Gelso:Nello stato normale e patologico nella tecnica dell'allevamento e della riproduzione. (Industria della preparazione del seme Bachi)-Enc. tela. Casa Ed. di Giuseppe Cesari,published. This was an important contribution to the literature on sericulture.
- Vladimir Nabokov begins organizing the butterfly collection of the Museum of Comparative Zoology at Harvard University.
- Ruggero Verity commenced Farfalle,in English Butterflies, of Italia (five volumes, 1940-1953).
- René Jeannel Faune cavernicole de la France, in English The Fauna of the Caves of France, published.
- André Badonnel Faune de France. Psocoptères. Paris. Paul Lechevalier 1943.
- Bernard Kettlewell begins research into the influence of industrial melanism on natural selection in moths.
- Willi Hennig publishes Grundzüge einer Theorie der phylogenetischen Systematikin Berlin. This was followed by
Kritische Bemerkungen zum phylogenetischen System der Insektenin 1953 and Phylogenetic Systematics in 1966. In these works Hennig founded cladistics.
- World programme for malaria eradication begins. Finally abandoned 1969.
- Roy Albert Crowson's The natural classification of the families of Coleoptera is published. This is a classic monograph.
- Clodoveo Carrión Mora died in Ecuador. Mora was a leading figure entomology of 20th century entomology in South America.
- Czesław Bieżanko publishes Álbum iconográfico dos Lepidópteros coletados por Biezanko. Papilionidae.
- Marta Grandi Ephemeroidea. Fauna d'Italia
- Genetic code is cracked. DNA was discovered by Friedrich Miescher in 1868, recognized as the bearer of genetic information in 1943 and revealed as a double helix by Rosalind Franklin in 1952. This leads to radical revision of the higher taxonomy of the Insecta.
- Morris Rockstein’s edited series—3 vols.—The Physiology of Insecta
- Takashi Shirozu Butterflies of Japan Illustrated in Colour published in Tokyo by Hokuryu-kan.
- First international Red Lists of endangered species were published.
- Murray S. Blum Fundamentals of Insect Physiology. New York: Wiley, 1985.
- Gerald A. Kerkut and L. I. Gilbert Comprehensive Insect Physiology, Biochemistry & Pharmacology.
- Naumann, I. D., P. B. Carne, J. F. Lawrence, E. S. Nielsen, J. P. Spradberry, R. W. Taylor, M. J. Whitten and M. J. Littlejohn, eds. The Insects of Australia: A Textbook for Students and Research Workers. Volume I and II. Second Edition. Carlton, Victoria, Melbourne University Press.
- Edward Grumbine, Ghost Bears: Exploring the Biodiversity Crisis reflects growing concerns. Insects are major indicators
of environmental destruction and impending mass extinction.
- Hoy, M. Insect molecular genetics. An introduction to principles and applications.
- Vladimir Nikolayevich Beklemiwev Методология систематики (Methodology of systematics).KMK Scientific Press Ltd.
- Loïc Matile Diptères d'Europe Occidentale Tomes 1 and 2 Atlas d'Entomologie.Editions N. Boubée.Paris.
- Gilbert, L.I. (ed.). 2004. Comprehensive molecular insect science, 7 vols. Elsevier Pergamon, published in St. Louis
- A paper in Science found that Culex pipiens mosquitoes existed in two populations in Europe, one which bites birds and one which bites humans. In North America 40% of Culex pipiens were found to be hybrids of the two types which bite both birds and humans, providing a vector for West Nile virus. This is thought to provide an explanation of why the West Nile disease has spread more quickly in North America than Europe.