181,307 research outputs found
From Rusty Genetics to Octopussy’s Garden
Alaimo critiques the “rusty” understanding of genetics, gender, and sex in Middlesex, advocating instead for queer ecological futurism
CELSS science needs
Questions and areas of study that need to be persued in order to develope a Controlled Ecological Life Support System are posed. Research topics needing attention are grouped under various leadings: ecology, genetics, plant pathology, cybernetics, chemistry, computer science, fluid dynamics, optics, and solid-state physics
Reverse Genetics in Ecological Research
By precisely manipulating the expression of individual genetic elements thought to be important for ecological performance, reverse genetics has the potential to revolutionize plant ecology. However, untested concerns about possible side-effects of the transformation technique, caused by Agrobacterium infection and tissue culture, on plant performance have stymied research by requiring onerous sample sizes. We compare 5 independently transformed Nicotiana attenuata lines harboring empty vector control (EVC) T-DNA lacking silencing information with isogenic wild types (WT), and measured a battery of ecologically relevant traits, known to be important in plant-herbivore interactions: phytohormones, secondary metabolites, growth and fitness parameters under stringent competitive conditions, and transcriptional regulation with microarrays. As a positive control, we included a line silenced in trypsin proteinase inhibitor gene (TPI) expression, a potent anti-herbivore defense known to exact fitness costs in its expression, in the analysis. The experiment was conducted twice, with 10 and 20 biological replicates per genotype. For all parameters, we detected no difference between any EVC and WT lines, but could readily detect a fitness benefit of silencing TPI production. A statistical power analyses revealed that the minimum sample sizes required for detecting significant fitness differences between EVC and WT was 2–3 orders of magnitude larger than the 10 replicates required to detect a fitness effect of TPI silencing. We conclude that possible side-effects of transformation are far too low to obfuscate the study of ecologically relevant phenotypes
Life history and ecological genetics of the colonial ascidian Botryllus schlosseri
The colonial ascidian Botryllus schlosseri is a cosmopolitan, marine filter feeder, introduced as a laboratory research
organism in the 1950s. Currently, it is widely used in many laboratories to investigate a variety of biological questions.
Recently, it has become a species of concern, as it is an invasive species in many coastal environments. Here, we review
studies on the geographical distribution of the species, sexual and asexual reproduction in the field, tolerance to
temperature, salinity and anthropogenic activity, polychromatism, enzymatic polymorphism, and the genetic basis of
pigmentation. Studying the relationship between genetic polymorphism and the adaptation of B. schlosseri to
environmental stress is a challenge of future research and will improve our understanding of its evolutionary success
and invasive potential
Technologically modified genes in natural populations
Current theories of evolutionary and ecological genetics cannot be used for general statements on risk assessment
of gene technology. In a simplifying model, the genes which are transferred from artificial populations are treated
like mutations in the natural populations. It is shown how fast such mutants can become fixed depending on the
transfer rate, the population size and the selection coefficient. However, our incomplete knowledge about living
systems still does not allow reliable risk assessments because of our incomplete understanding of the underlying
principles
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