After graduating with top marks from Collège Saint Marc, I enrolled in the Faculty of Agriculture at the University of Alexandria, envisioning a future as an agronomist managing a family farm. It was there, during my first two years, that I was introduced to the vast diversity of microbial, plant, and animal life and, most importantly, to the remarkable power of selection in shaping the incredible variation we see under domestication.

When I joined the Department of Genetics in my third year, I was captivated by the realization that so much biological diversity could arise from combinations of just four letters—A, T, C, and G, the four nucleotide bases of DNA. The elegant mathematical equations of quantitative and population genetics offered a robust and predictable framework for understanding how simple genotypes could give rise to complex phenotypes, and how these processes shape genetic variation across time and space.

My graduation in 2002 coincided with the inauguration of the new Bibliotheca Alexandrina. After participating in a competition held there, I was selected to represent Egyptian youth at the 2nd Earth Summit in Johannesburg, South Africa. This experience was pivotal for me. Genetic equations, I realized, are not only key to understanding the past and the origins of agricultural varieties but also essential for predicting the future and conserving our rapidly depleting biodiversity. How can we protect species from extinction if we do not first understand how they come into being?

Upon returning from the conference, I decided to pursue an academic career in population genetics. As the top graduate of my class, I was offered an assistant teacher position in the Department of Genetics at the University of Alexandria. I approached my professors about conducting an M.Sc. thesis in population genetics, specifically requesting to work on a marine organism. My mentor, Ahmed ElMetainy, suggested I focus on Drosophila instead. I ultimately completed my thesis under the supervision of his wife, Amira Abou-Youssef, on the population genetics of Drosophila in the oases of Egypt’s Western Desert. I am deeply grateful to both of them for introducing me to the Drosophila model—a model I have continued to work with for over 20 years.

In 1956–1957, Theodosius Dobzhansky spent six months in Egypt, collecting Drosophila across the country and studying chromosomal inversion polymorphisms in various populations. He was accompanied by a group of young Egyptian geneticists from the University of Alexandria, who would later establish the Department of Genetics there in the early 1960s. Most of these geneticists had completed their PhDs on Drosophila at the University of Edinburgh, UK, and were thus well-versed in Drosophila quantitative and population genetics.

For nearly 15 years, they conducted extensive research on Egypt’s Drosophila fauna, primarily around Alexandria. One of their major findings was the gradual replacement of Drosophila melanogaster by D. simulans in agricultural fields. Many of their studies focused on the interactions between these two species, particularly in relation to diet and temperature. Among the most prominent scholars in this group was Abdel-Aziz Tantawy, who corresponded with Sewall Wright. Tantawy conducted some of the first comparative studies of Afrotropical populations of both species against temperate populations.

Work on Drosophila population genetics in Egypt continued into the 1970s, focusing on allozyme variation, and in the 1980s, on the spread of P-elements. However, by the 1990s, Drosophila studies had nearly disappeared, replaced by molecular genetics and its biotechnological applications, which were deemed more relevant to addressing the country’s needs.

I was therefore fortunate that my professors agreed to revive research on Egyptian Drosophila in the early 2000s. Near Alexandria, I discovered the introduction of two Afrotropical drosophilids in Egypt: Zaprionus indianus (a notorious fig pest) and Z. tuberculatus. These two invasive species are now replacing both D. melanogaster and D. simulans. At the time, only a French laboratory in Gif-sur-Yvette was studying flies of the genus Zaprionus. Thanks to a bursary from the French Embassy, I completed a one-month training in this lab.

Research on the two invasive Zaprionus species has continued in Egypt under the leadership of Amira Abou-Youssef. Since 2019, I have renewed collaborations with Egyptian researchers to better understand the genomic basis of these tropical species’ adaptation to Egypt’s arid environment and their potential impact on fruit production.

After World War II, Teissier became the first president of the newly established CNRS. At Gif-sur-Yvette, he launched biometrical studies of geographical populations of Drosophila melanogaster, as well as some of the earliest behavioral experiments on sexual selection in the species. However, it was under the leadership of his student and successor, Charles Bocquet, that research on the Afrotropical drosophilid fauna truly took off. This effort was primarily driven by Léonidas Tsacas and his students, Daniel Lachaise and Françoise Lemeunier, who were later joined by Jean R. David, a professor of Drosophila ecophysiology at the University of Lyon.

It was through the work of these researchers that the Afrotropical origin of Drosophila melanogaster was demonstrated, primarily due to the discovery in the 1970s of several closely related species endemic to this region. This finding filled a critical gap in the evolutionary history of the most genetically studied organism.

Under the leadership of Jean David in the 1980s, the laboratory focused its efforts on the species of the melanogaster subgroup, establishing this clade as a primary model in evolutionary genetics and speciation. The lab diversified its approaches, expanding from cytological and biochemical genetics to include behavior and ecology. After Jean David’s retirement, the laboratory became a hub for molecular population genetics and broadened its research to include organisms beyond Drosophila. Yet, the spirit of conducting evolutionary studies within an integrative framework—combining genetics, behavior, and ecology—endures, as reflected in the laboratory’s current name.

Jean David is undoubtedly the most influential figure in my scientific career. I joined his laboratory in 2004 and later as a PhD student (2005–2007). My doctoral research focused on the systematics and ecological genetics of the genus Zaprionus, a subject he was deeply invested in, particularly through collaborations with Brazilian colleagues. I continued to collaborate with Jean during my postdoctoral years and had the privilege of participating in multiple field collection trips across Africa with him. I learned as much from him in the field as I did in the laboratory. He was 87 years old during our last mission on the island of Ngazidja (Grande Comore).

Today, the laboratory continues to explore various aspects of Drosophila evolutionary genetics, including comparative genomics, evolutionary developmental biology (evo-devo), and behavioral ecology.