Université de Fribourg

Distinct genomic signals of lifespan and life history evolution in response to postponed reproduction and larval diet in Drosophila

Hoedjes, Katja M. ; van den Heuvel, Joost ; Kapun, Martin ; Keller, Laurent ; Flatt, Thomas ; Zwaan, Bas J.

In: Evolution Letters, 2019, p. -

Reproduction and diet are two major factors controlling the physiology of aging and life history, but how they interact to affect the evolution of longevity is unknown. Moreover, although studies of large‐effect mutants suggest an important role of nutrient sensing pathways in regulating aging, the genetic basis of evolutionary changes in lifespan remains poorly understood. To address these...

Université de Fribourg

A clinal polymorphism in the insulin signaling transcription factor foxo contributes to life-history adaptation in Drosophila*

Durmaz, Esra ; Rajpurohit, Subhash ; Betancourt, Nicolas ; Fabian, Daniel K. ; Kapun, Martin ; Schmidt, Paul ; Flatt, Thomas

In: Evolution, 2019, vol. 73, no. 9, p. 1774–1792

A fundamental aim of adaptation genomics is to identify polymorphisms that underpin variation in fitness traits. In Drosophila melanogaster, latitudinal life‐history clines exist on multiple continents and make an excellent system for dissecting the genetics of adaptation. We have previously identified numerous clinal single‐nucleotide polymorphism in insulin/insulin‐like growth factor...

Université de Fribourg

The genomic and physiological basis of life history variation in a butterfly metapopulation

Klepsatel, Peter ; Flatt, Thomas

In: Molecular Ecology, 2011, vol. 20, no. 9, p. 1795-1798

Unravelling the mechanisms underlying variation in life history traits is of fundamental importance for our understanding of adaptation by natural selection. While progress has been made in mapping fitness-related phenotypes to genotypes, mainly in a handful of model organisms, functional genomic studies of life history adaptations are still in their infancy. In particular, despite a few...

Université de Fribourg

A role for genetic accommodation in evolution?

Braendle, Christian ; Flatt, Thomas

In: BioEssays, 2006, no. 28, p. 868-873

Whether evolutionary change can occur by genetic assimilation, or more generally by genetic accommodation, remains controversial. Here we examine some of the experimental evidence for both phenomena. Several experiments in Drosophila suggest that assimilation is possible, and a new paper1 shows that a color polyphenism in the tobacco hornworm, Manduca sexta, can evolve by genetic ...

Université de Fribourg

Juvenile and Steroid Hormones in Drosophila melanogaster Longevity

Flatt, Thomas ; Tu, Meng-Ping ; Tatar, Marc

In: The Handbook of the Biology of Aging, 2006, p. 415-448

This chapter reviews hormonal effects on aging in Drosophila melanogaster. The insect juvenile hormone (JH) is a sesquiterpenoid compound produced by the corpora allata (CA), a pair of endocrine glands with nervous connections to the brain. In pre- adult development and metamorphosis, JH functions as a "status quo" hormone, allowing continued growth after ecdysteroid-induced molting....

Université de Fribourg

Evolution in group-structured populations can resolve the tragedy of the commons

Killingback, Timothy ; Bieri, Jonas ; Flatt, Thomas

In: Proceeding of the Royal Society, 2006, no. 273, p. 1477–1481

Public goods are the key features of all human societies and are also important in many animal societies. Collaborative hunting and collective defence are but two examples of public goods that have played a crucial role in the development of human societies and still play an important role in many animal societies. Public goods allow societies composed largely of cooperators to outperform...

Université de Fribourg

Comparing thyroid and insect hormone signaling

Flatt, Thomas ; Moroz, Leonid L. ; Tatar, Marc ; Heyland, Andreas

In: Integrative and Comparative Biology, 2006, vol. 46, no. 6, p. 777-794

Transitions between different states of development, physiology, and life history are typically mediated by hormones. In insects, metamorphosis and reproductive maturation are regulated by an interaction between the sesquiterpenoid juvenile hormone (JH) and the steroid 20-hydroxy-ecdysone (20E). In vertebrates and some marine invertebrates, the lipophilic thyroid hormones (THs) affect...

Université de Fribourg

Hormonal pleiotropy and the juvenile hormone regulation of Drosophila development and life history

Flatt, Thomas ; Tu, Meng-Ping ; Tatar, Marc

In: BioEssays, 2005, vol. 27, no. 10, p. 999-1010

Understandinghowtraits are integrated at the organismal level remains a fundamental problem at the interface of developmental and evolutionary biology. Hormones, regulatory signaling molecules that coordinate multiple developmental and physiological processes, are major determinants underlying phenotypic integration. The probably best example for this is the lipid-like juvenile hormone (JH)...

Université de Fribourg

The evolutionary genetics of canalization

Flatt, Thomas

In: The Quarterly Review of Biology, 2005, vol. 80, no. 3, p. 287-316

Evolutionary genetics has recently made enormous progress in understanding how genetic variation maps into phenotypic variation. However, why some traits are phenotypically invariant despite apparent genetic and environmental changes has remained a major puzzle. In the 1940s, Conrad Hal Waddington coined the concept and term “canalization” to describe the robustness of phenotypes to...

Université de Fribourg

The interplay between immunity and aging in Drosophila

Garschall, Kathrin ; Flatt, Thomas

In: F1000Research, 2018, vol. 7, p. 160

Here, we provide a brief review of the mechanistic connections between immunity and aging—a fundamental biological relationship that remains poorly understood—by considering two intertwined questions: how does aging affect immunity, and how does immunity affect aging? On the one hand, aging contributes to the deterioration of immune function and predisposes the organism to infections...