Université de Fribourg

What is metamorphosis?

Bishop, C. D. ; Erezyilmaz, D. F. ; Flatt, Thomas ; Georgiou, C. D. ; Hadfield, M. G. ; Heyland, A. ; Hodin, J. ; Jacobs, M. W. ; Malakova, S. A. ; Pires, A. ; Reitzel, A. M. ; Santagata, S. ; Tanaka, K. ; Youson, J. H.

In: Integrative and Comparative Biology, 2006, vol. 46, no. 6, p. 655-661

Metamorphosis (Gr. meta- “change” + morphe “form”) as a biological process is generally attributed to a subset of animals: most famously insects and amphibians, but some fish and many marine invertebrates as well. We held a symposium at the 2006 Society for Integrative and Comparative Biology (SICB) annual meeting in Orlando, FL (USA) to discuss metamorphosis in a comparative context....

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

Similarities and differences in altitudinal versus latitudinal variation for morphological traits in Drosophila melanogaster

Klepsatel, Peter ; Gáliková, Martina ; Huber, Christian D. ; Flatt, Thomas

In: Evolution, 2014, vol. 68, no. 5, p. 1385–1398

Understanding how natural environments shape phenotypic variation is a major aim in evolutionary biology. Here, we have examined clinal, likely genetically based variation in morphology among 19 populations of the fruit fly (Drosophila melanogaster) from Africa and Europe, spanning a range from sea level to 3000 m altitude and including locations approximating the southern and northern range...

Université de Fribourg

Inference of chromosomal inversion dynamics from Pool-Seq data in natural and laboratory populations of Drosophila melanogaster

Kapun, Martin ; van Schalkwyk, Hester ; McAllister, Bryant ; Flatt, Thomas ; Schlötterer, Christian

In: Molecular Ecology, 2014, vol. 23, no. 7, p. 1813–1827

Sequencing of pools of individuals (Pool‐Seq) represents a reliable and cost‐effective approach for estimating genome‐wide SNP and transposable element insertion frequencies. However, Pool‐Seq does not provide direct information on haplotypes so that, for example, obtaining inversion frequencies has not been possible until now. Here, we have developed a new set of diagnostic marker...

Université de Fribourg

Variation in thermal performance and reaction norms among populations of Drosophila melanogaster

Klepsatel, Peter ; Gáliková, Martina ; De Maio, Nicola ; Huber, Christian D. ; Schlötterer, Christian ; Flatt, Thomas

In: Evolution, 2013, vol. 67, no. 12, p. 3573–3587

The major goal of evolutionary thermal biology is to understand how variation in temperature shapes phenotypic evolution. Comparing thermal reaction norms among populations from different thermal environments allows us to gain insights into the evolutionary mechanisms underlying thermal adaptation. Here, we have examined thermal adaptation in six wild populations of the fruit fly (Drosophila...

Université de Fribourg

Reproductive and post-reproductive life history of wild-caught Drosophila melanogaster under laboratory conditions

Klepsatel, P. ; Gáliková, M. ; De Maio, N. ; Ricci, S. ; Schlötterer, C. ; Flatt, Thomas

In: Journal of Evolutionary Biology, 2013, vol. 26, no. 7, p. 1508–1520

The life history of the fruit fly (Drosophila melanogaster) is well understood, but fitness components are rarely measured by following single individuals over their lifetime, thereby limiting insights into lifetime reproductive success, reproductive senescence and post‐reproductive lifespan. Moreover, most studies have examined long‐ established laboratory strains rather than freshly...