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Hire Dr. Felix Z.

United Kingdom

USD 90 /hr

Senior Research Consultant | R-Statistical Modelling & Evidence Synthesis | UK & German & EU Remote Support

Profile Summary

I am a PhD scientist with over 20 years of international experience in complex biological research and high-level data validation. I specialize in building reproducible analytical pipelines in R to transform complex datasets into clear, evidence-based narratives for strategic decision-making. With a record of over 100 expert peer reviews for global scientific journals, I provide a rigorous level of quality assurance for technical reports, grant applications, and regulatory submissions. I am located in the Liverpool region, UK. As a German citizen and native speaker, I offer the added advantage of being fully available for remote work within the EU, facilitating seamless cross-border collaboration. Core Expertise: • Statistical Validation: Expert in ensuring the rigor of complex biological and environmental datasets, utilizing GLMM, GAMM, survival analysis, longitudinal analysis, and meta-analysis. • Scientific Writing: Translating high-level research into actionable narratives for non-specialist stakeholders and decision-makers. • Methodological Design: Building robust frameworks for experiments, research integrity, and impact assessments. • EU-UK Scientific Liaison: Facilitating communication and research integrity across German and British scientific environments to streamline international projects. • Advanced R Analysis & Visualization: Building reproducible analytical pipelines to transform complex data into clear, strategic insights.

Subject Matter Expertise

• ☆ Biostatistics
• ☆ Statistics
• ☆ Meta-Analysis
• ☆ Nonlinear Regression
• ☆ Study Design
• ☆ Technical & Scientific Writing
• ☆ Manuscript & Journal Article Writing
• ☆ Experimental Protocols
• ☆ Science Communication
• ☆ Scientific Proofreading & Editing

Services

• Writing
• Research
• Consulting
• Data & AI

Writing Technical Writing, General Proofreading & Editing, Translation

Research Meta-Research, Scientific and Technical Research, Systematic Literature Review

Consulting Scientific and Technical Consulting

Data & AI Statistical Analysis, Data Visualization, Data Mining, Data Cleaning, Data Processing, Data Insights

Work Experience

Visiting Lecturer

Liverpool John Moores University

2023 - Present

Postdoctoral Researcher

University of New South Wales

2018 - December 2019

MONASH UNIVERSITY

- May 2018

Postdoc

Monash University

October 2015 - 2018

Postdoctoral fellow

George Washington University

2014 - 2015

Uppsala University

- 2013

Affiliated

Station d'Ecologie Experimentale du CNRS à Moulis

2008 - 2010

Education

University of Tasmania

- 2001

Ludwig-Maximilians-Universitat Munich

- 2000

Certifications

• Certification details not provided.

Publications

JOURNAL ARTICLE

Felix Zajitschek, Susanne R. K. Zajitschek, Ana C. O. Vasconcelos, Russell Bonduriansky (2023). Dietary restriction fails to extend life in stressful environments . Functional Ecology.

Krish Sanghvi, Felix Zajitschek, Maider Iglesias-Carrasco, Megan L. Head (2021). Sex- and trait-specific silver-spoon effects of developmental environments, on ageing . Evolutionary Ecology.

Susanne RK Zajitschek, Felix Zajitschek, Russell Bonduriansky, Robert C Brooks, Will Cornwell, Daniel S Falster, Malgorzata Lagisz, Jeremy Mason, Alistair M Senior, Daniel WA Noble, et al.(2020). Sexual dimorphism in trait variability and its eco-evolutionary and statistical implications . eLife. 9. {eLife} Sciences Publications, Ltd

Felix Zajitschek, Susanne Zajitschek, Russell Bonduriansky (2020). Senescence in wild insects: Key questions and challenges . Functional Ecology.

Susanne Zajitschek, Felix Zajitschek, Sarah Josway, Reem Al Shabeeb, Halli Weiner, Mollie K. Manier (2019). Costs and benefits of giant sperm and sperm storage organs in Drosophila melanogaster . Journal of Evolutionary Biology.

Felix Zajitschek, Tim Connallon(2018). Antagonistic pleiotropy in species with separate sexes, and the maintenance of genetic variation in life‐history traits and fitness . Evolution. 72. (6). p. 1306--1316. Wiley

(2018). Evolution under dietary restriction decouples survival from fecundity in Drosophila melanogaster females . Journals of Gerontology: Biological Sciences.

Felix Zajitschek, Susanne Zajitschek, Mollie Manier(2017). Correction to ‘High-protein paternal diet confers an advantage to sons in sperm competition’ . Biology Letters. 13. (7). p. 20170297. The Royal Society

Susanne Zajitschek, James E. Herbert-Read, Nasir M. Abbasi, Felix Zajitschek, Simone Immler(2017). Paternal personality and social status influence offspring activity in zebrafish . BMC Evolutionary Biology. 17. (1). BioMed Central

F. Zajitschek, T. Connallon(2017). Partitioning of resources: the evolutionary genetics of sexual conflict over resource acquisition and allocation . Journal of Evolutionary Biology. 30. (4). p. 826--838. Wiley

Partitioning of resources: the evolutionary genetics of sexual conflict over resource allocation @article{010522fe3be348fdbcc79283bb2fdccc, title = "Partitioning of resources: the evolutionary genetics of sexual conflict over resource allocation", abstract = "Fitness depends on both the resources that individuals acquire and the allocation of those resources to traits that influence survival and reproduction. Optimal resource allocation differs between females and males as a consequence of their fundamentally different reproductive strategies. However,because most traits have a common genetic basis between the sexes, conflicting selection between the sexes over resource allocation can constrain the evolution of optimal allocation within each sex, and generate trade-offs for fitness between them (i.e. “sexual antagonism” or “intralocus sexual conflict”).The theory of resource acquisition and allocation provides an influential framework for linking genetic variation in acquisition and allocation to empirical evidence of trade-offs between distinct life history traits. However, these models have not considered the emergence of trade-offs within the context of sexual dimorphism, where they are expected to be particularly common. Here, we extend acquisition-allocation theory and develop a quantitative genetic framework for predicting genetically based trade-offs between life-history traits within sexes and between female and male fitness. Our models demonstrate that empirically measurable evidence of sexually antagonistic fitness variation should depend upon three interacting factors that may vary between populations: (1) the genetic variances and between-sex covariances for resource acquisition and allocation traits, (2) condition dependent expression of resource allocation traits, and (3) sex differences in selection on the allocation of resource to different fitness components.", author = "Felix Zajitschek and Tim Connallon", year = "2017", month = "4", doi = "10.1111/jeb.13051", language = "English", volume = "30", pages = "826--838", journal = "Journal of Evolutionary Biology", issn = "1010-061X", publisher = "Wiley-Blackwell", number = "4", } . Journal of Evolutionary Biology.

Felix Zajitschek, Susanne Zajitschek, Mollie Manier(2017). High-protein paternal diet confers an advantage to sons in sperm competition . Biology Letters. 13. (2). p. 20160914. The Royal Society

Felix Zajitschek, Susanne Zajitschek, Mollie Manier(2017). High-protein paternal diet confers an advantage to sons in sperm competition . Biology Letters. 13. (2). Royal Society, The

(2016). Evolution under dietary restriction increases male reproductive performance without survival cost. Proceedings of the Royal Society London B.

Felix Zajitschek, Susanne R. K. Zajitschek, Cindy Canton, Grigorios Georgolopoulos, Urban Friberg, Alexei A. Maklakov(2016). Evolution under dietary restriction increases male reproductive performance without survival cost . Proceedings of the Royal Society B: Biological Sciences. 283. (1825). p. 20152726. The Royal Society

Evolution under dietary restriction increases male reproductive performance without survival cost @article{81e744d4f7b24845aaa4f30eae88b27d, title = "Evolution under dietary restriction increases male reproductive performance without survival cost", abstract = "Dietary restriction (DR), a reduction in nutrient intake without malnutrition, is the most reproducible way to extend lifespan in a wide range of organisms across the tree of life, yet the evolutionary underpinnings of the DR effect on lifespan are still widely debated. The leading theory suggests that this effect is adaptive and results from reallocation of resources from reproduction to somatic maintenance, in order to survive periods of famine in nature. However, such response would cease to be adaptive when DR is chronic and animals are selected to allocate more resources to reproduction. Nevertheless, chronic DR can also increase the strength of selection resulting in the evolution of more robust genotypes. We evolved Drosophila melanogaster fruit flies on ‘DR’, ‘standard’ and ‘high’ adult diets in replicate populations with overlapping generations. After approximately 25 generations of experimental evolution, male ‘DR’ flies had higher fitness than males from ‘standard’ and ‘high’ populations. Strikingly, this increase in reproductive success did not come at a cost to survival. Our results suggest that sustained DR selects for more robust male genotypes that are overall better in converting resources into energy, which they allocate mostly to reproduction.", keywords = "adaptation, dietary stress, Drosophila melanogaster, nutrition", author = "Felix Zajitschek and Zajitschek, {Susanne R K} and Cindy Canton and Grigorios Georgolopoulos and Urban Friberg and Maklakov, {Alexei A}", year = "2016", month = "2", day = "24", doi = "10.1098/rspb.2015.2726", language = "English", volume = "283", pages = "1--6", journal = "Proceedings of the Royal Society B: Biological Sciences", issn = "0962-8452", publisher = "The Royal Society Publishing", number = "1825", } . Proceedings of the Royal Society B: Biological Sciences.

Zajitschek, Felix, Jin, Tuo, Colchero, Fernando, Maklakov, Alexei A.(2014). Aging Differently: Diet- and Sex-Dependent Late-Life Mortality Patterns in Drosophila melanogaster . Journals of Gerontology Series a-Biological Sciences and Medical Sciences. 69. (6). p. 666-674.

Zajitschek, Susanne, Hotzy, Cosima, Zajitschek, Felix, Immler, Simone(2014). Short-term variation in sperm competition causes sperm-mediated epigenetic effects on early offspring performance in the zebrafish . Proceedings of the Royal Society B-Biological Sciences. 281. (1785).

Hwei-yen Chen, Felix Zajitschek, Alexei A Maklakov(2013). Why ageing stops . Biology Letters. 9. (5). p. 1 -- 4. Royal Society, The

Felix Zajitschek, Susanne RK Zajitschek, Urban Friberg, Alexei A Maklakov(2013). Interactive effects of sex, social environment, dietary restriction, and methionine on survival and reproduction in fruit flies . Journal of the American Aging Association. 35. (4). p. 1193 -- 1204. Springer-Verlag London Ltd.

Chen, Hwei-yen, Zajitschek, Felix, Maklakov, Alexei A.(2013). Why ageing stops: heterogeneity explains late-life mortality deceleration in nematodes . Biology Letters. 9. (5).

Zajitschek, F., Lailvaux, S. P., Dessmann, J., Brooks, R.(2012). Diet, sex, and death in field crickets . Ecology and Evolution. 2. p. 1627-1636.

Felix Zajitschek, Simon P Lailvaux, Josephine Dessmann, Rob Brooks(2012). Diet, sex, and death in field crickets . Ecology and Evolution. 2. (7). p. 1627 -- 1636. Wiley-Blackwell

Zajitschek, F., Zajitschek, S. R. K., Friberg, U., Maklakov, Alexei A.(2012). Interactive effects of sex, social environment, dietary restriction and methionine on survival and reproduction in fruit flies. Age.

Archer, C. R., Zajitschek, F., Sakaluk, S. K., Royle, N. J., Hunt, J.(2012). Sexual selection affects the evolution of lifespan and ageing in the decorated cricket Gryllodes sigillatus . Evolution. 66. p. 3088-3100.

Catharine Ruth Archer, Felix Zajitschek, Scott K Sakaluk, Nick J Royle, John Hunt(2012). Sexual selection affects the evolution of lifespan and ageing in the decorated cricket Gryllodes sigillatus . Evolution. 66. (10). p. 3088 -- 3100. Wiley-Blackwell

Legrand, D., Guillaume, O., Baguette, M., Cote, J., Trochet, A., Calvez, O., Zajitschek, S., Zajitschek, F., Lecomte, J., Benard, Q., et al.(2012). The Metatron: an experimental system to study dispersal and metaecosystems for terrestrial organisms . Nature Methods. 9. p. 828-+.

Delphine Legrand, Olivier Guillaume, Michel Baguette, Julien Cote, Audrey Trochet, Olivier Calvez, Susanne RK Zajitschek, Felix Zajitschek, Jane Lecomte, Quentin Benard, et al.(2012). The Metatron: an experimental system to study dispersal and metaecosystems for terrestrial organisms . Nature Methods. 9. (8). p. 828 -- 833. Nature Publishing Group

Zajitschek, S. R. K., Zajitschek, F., Miles, D. B., Clobert, J.(2012). The effect of coloration and temperature on sprint performance in male and female wall lizards . Biological Journal of the Linnean Society. 107. p. 573-582.

Susanne RK Zajitschek, Felix Zajitschek, Donald B Miles, Jean Clobert(2012). The effect of coloration and temperature on sprint performance in male and female wall lizards . Biological Journal of the Linnean Society. 107. (3). p. 573 -- 582. Wiley-Blackwell

Zajitschek, S. R. K., Zajitschek, F., Clobert, J.(2012). The importance of habitat resistance for movement decisions in the common lizard, Lacerta vivipara . Bmc Ecology. 12.

Susanne Zajitschek, Felix Zajitschek, Jean Clobert(2012). The importance of habitat resistance for movement decisions in the common lizard, Lacerta vivipara . BMC Ecology. 12. p. 1 -- 9. Springer-Verlag London Ltd.

Lailvaux, S. P., Zajitschek, F., Dessman, J., Brooks, R.(2011). Differential aging of bite and jump performance in virgin and mated Teleogryllus commodus crickets . Evolution. 65. p. 3138-3148.

Simon P Lailvaux, Felix Zajitschek, Josephine Dessmann, Robert C Brooks(2011). Differential aging of bite and jump performance in virgin and mated Teleogryllus commodus crickets . Evolution. 65. (11). p. 3138 -- 3147. Wiley-Blackwell

Zajitschek, Felix(2010). To the core of behavioral ecology . Trends in Ecology & Evolution. 25. p. 494.

Zajitschek, Susanne R. K., Zajitschek, Felix, Brooks, Robert C.(2009). Demographic costs of inbreeding revealed by sex-specific genetic rescue effects . BMC evolutionary biology. 9. p. 289.

Susanne RK Zajitschek, Felix Zajitschek, Robert C Brooks(2009). Demographic costs of inbreeding revealed by sex-specific genetic rescue effects . BMC Evolutionary Biology. 9. (1). p. 1 -- 9. BioMed Central

Zajitschek, F., Hunt, J., Jennions, M. D., Hall, M. D., Brooks, R. C.(2009). Effects of juvenile and adult diet on ageing and reproductive effort of male and female black field crickets, Teleogryllus commodus . Functional Ecology. 23. p. 602-611.

Felix Zajitschek, John Hunt, Michael Jennions, Matthew David Hall, Rob Brooks(2009). Effects of juvenile and adult diet on ageing and reproductive effort of male and female black field crickets, Teleogryllus commodus . Functional Ecology. 23. (3). p. 602 -- 611. Wiley-Blackwell

Maklakov, A. A., Hall, M. D., Simpson, S. J., Dessmann, J., Clissold, F. J., Zajitschek, F., Lailvaux, S. P., Raubenheimer, D., Bonduriansky, R., Brooks, R. C.(2009). Sex differences in nutrient-dependent reproductive ageing . Aging Cell. 8. p. 324-30.

Zajitschek, Felix, Brassil, Chad E., Bonduriansky, Russell, Brooks, Robert C.(2009). Sex effects on life span and senescence in the wild when dates of birth and death are unknown . Ecology. 90. p. 1698-707.

Alexei A Maklakov, Matthew David Hall, Stephen J Simpson, Josephine Dessmann, Fiona Jayne Clissold, Felix Zajitschek, Simon P Lailvaux, David Raubenheimer, Russell Bonduriansky, Rob Brooks(2009). Sex differences in nutrient-dependent reproductive ageing . Aging Cell. 8. (3). p. 324 -- 330. Wiley-Blackwell

Felix Zajitschek, Chad E Brassil, Russell Bonduriansky, Robert C Brooks(2009). Sex effects on life span and senescence in the wild when dates of birth and death are unknown . Ecology. 90. (6). p. 1698 -- 1707. Ecological Society of America

Zajitschek, F., Bonduriansky, R., Zajitschek, S. R. K., Brooks, R. C.(2009). Sexual dimorphism in life history: Age, survival, and reproduction in male and female field crickets Teleogryllus commodus under seminatural conditions . American Naturalist. 173. p. 792-802.

Felix Zajitschek, Russell Bonduriansky, Susanne RK Zajitschek, Robert C Brooks(2009). Sexual dimorphism in life history: age, survival, and reproduction in male and female field crickets Teleogryllus commodus under seminatural conditions . American Naturalist. 173. (6). p. 792 -- 802. The University of Chicago Press

Maklakov, Alexei, Simpson, Stephen J., Zajitschek, Felix, Hall, Matthew D., Dessmann, Josephine, Clissold, Fiona, Raubenheimer, David, Bonduriansky, Russell, Brooks, Robert C.(2008). Sex-specific fitness effects of nutrient intake on reproduction and lifespan . Current biology. 18. p. 1062-6.

Alexei A Maklakov, Stephen J Simpson, Felix Zajitschek, Matthew David Hall, Josephine Dessmann, Fiona Jayne Clissold, David Raubenheimer, Russell Bonduriansky, Rob Brooks(2008). Sex-specific fitness effects of nutrient intake on reproduction and lifespan . Current Biology. 18. (14). p. 1062 -- 1066. Elsevier

Bonduriansky, R., Maklakov, Alexei A., Zajitschek, F., Brooks, R.(2008). Sexual selection, sexual conflict and the evolution of ageing and life span . Functional Ecology. 22. p. 443-453.

Russell Bonduriansky, A Maklakov, Felix Zajitschek, Robert C. Brooks(2008). Sexual selection, sexual conflict and the evolution of ageing and life span . Functional Ecology. 22. (3). p. 443–453. Wiley-Blackwell

Zajitschek, Felix, Hunt, John, Zajitschek, Susanne R. K., Jennions, Michael D., Brooks, Robert(2007). No intra-locus sexual conflict over reproductive fitness or ageing in field crickets . Plos One. 2. p. e155.

Felix Zajitschek, John Hunt, Susanne Zajitschek, Michael Jennions, Robert C. Brooks(2007). No intra-locus sexual conflict over reproductive fitness or ageing in field crickets . PLoS ONE. 2. (1). Public Library of Science

Hunt, John, Blows, Mark W., Zajitschek, Felix, Jennions, Michael D., Brooks, Robert(2007). Reconciling strong stabilizing selection with the maintenance of genetic variation in a natural population of black field crickets (Teleogryllus commodus) . Genetics. 177. p. 875-80.

John Hunt, Mark W Blows, Felix Zajitschek, Michael Jennions, Robert C. Brooks(2007). Reconciling strong stabilizing selection with the maintenance of genetic variation in a natural population of black field crickets (Teleogryllus commodus) . Genetics. 177. (2). p. 875–880. Genetics Society of America

PREPRINT

Dietary restriction fails to extend life in stressful environments <head> <META HTTP-EQUIV="Refresh" CONTENT="0;URL=/servlet/useragent"> </head> .

S.R.K. Zajitschek, F. Zajitschek, R. Bonduriansky, R.C. Brooks, W. Cornwell, D.S. Falster, M. Lagisz, J. Mason, A. M. Senior, D. A. W. Noble, et al. (2020). Sex and Power: sexual dimorphism in trait variability and its eco-evolutionary and statistical implications .