Université de Fribourg

Winter weather affects asp viper Vipera aspis population dynamics through susceptible juveniles

Altwegg, Res ; Dummermuth, Stefan ; Anholt, Bradley R. ; Flatt, Thomas

In: Oikos, 2005, vol. 110, no. 1, p. 55-66

Detailed studies on mammals and birds have shown that the effects of climate variation on population dynamics often depend on population composition, because weather affects different subsets of a population differently. It is presently unknown whether this is also true for ectothermic animals such as reptiles. Here we show such an interaction between weather and demography for an ectothermic...

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

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

Ubiquitous overexpression of the DNA repair factor dPrp19 reduces DNA damage and extends Drosophila life span

Garschall, Kathrin ; Dellago, Hanna ; Gáliková, Martina ; Schosserer, Markus ; Flatt, Thomas ; Grillari, Johannes

In: npj Aging and Mechanisms of Disease, 2017, vol. 3, no. 1, p. 5

Mechanisms that ensure and maintain the stability of genetic information are fundamentally important for organismal function and can have a large impact on disease, aging, and life span. While a multi-layered cellular apparatus exists to detect and respond to DNA damage, various insults from environmental and endogenous sources continuously affect DNA integrity. Over time this can lead to the...

Université de Fribourg

Transcriptome analysis reveals a major impact of JAK protein tyrosine kinase 2 (Tyk2) on the expression of interferon-responsive and metabolic genes

Vogl, Claus ; Flatt, Thomas ; Fuhrmann, Bernd ; Hofmann, Elisabeth ; Wallner, Barbara ; Stiefvater, Rita ; Kovarik, Pavel ; Strobl, Birgit ; Müller, Mathias

In: BMC Genomics, 2010, vol. 11, no. 199, p. 1-19

Background: Tyrosine kinase 2 (Tyk2), a central component of Janus kinase/signal transducer and activator of transcription (JAK/STAT) signaling, has major effects on innate immunity and inflammation. Mice lacking Tyk2 are resistant to endotoxin shock induced by lipopolysaccharide (LPS), and Tyk2 deficient macrophages fail to efficiently induce interferon alpha/beta after LPS treatment....

Université de Fribourg

Survival costs of reproduction in Drosophila

Flatt, Thomas

In: Experimental Gerontology, 2011, vol. 46, no. 5, p. 369–375

Université de Fribourg

Still Pondering an Age-Old Question

Flatt, Thomas ; Promislow, Daniel E. L.

In: Science, 2007, vol. 318, p. 1255-1256

A theory of trade-offs to explain why we age has spurred 50 years of interdisciplinary research in evolution and molecular genetics.

Université de Fribourg

Steroid hormone regulation of C. elegans and Drosophila aging and life history

Gáliková, Martina ; Klepsatel, Peter ; Senti, Gabriele ; Flatt, Thomas

In: Experimental Gerontology, 2011, vol. 46, no. 2, p. 141–147

In the last two decades it has become clear that hormones and gene mutations in endocrine signaling pathways can exert major effects on lifespan and related life history traits in worms, flies, mice, and other organisms. While most of this research has focused on insulin/insulin-like growth factor-1 signaling, a peptide hormone pathway, recent work has shown that also lipophilic hormones play...

Université de Fribourg

Stabilizing factors interact in promoting host–parasite coexistence

Flatt, Thomas ; Scheuring, István

In: Journal of Theoretical Biology, 2004, vol. 228(2), p. 241

Understanding the mechanisms that promote coexistence among species is a fundamental problem in evolutionary ecology. Such mechanisms include environmental noise, spatial population structure, density dependence, and genetic variation. In natural populations such factors may exert combined effects on coexistence. Thus, to disentangle the contribution of several factors to coexistence, their...