So far in this course we have dealt entirely with the evolution of characters that are controlled by simple Mendelian inheritance at a single locus. There are notes on the course website about gametic disequilibrium and how allele frequencies change at two loci simultaneously, but we didn’t discuss them. In every example we’ve considered we’ve imagined that we could understand something about evolution by examining the evolution of a single gene. That’s the domain of classical population genetics. For the next few weeks we’re going to be exploring a field that’s actually older than classical population genetics, although the approach we’ll be taking to it involves the use of population genetic machinery. If you know a little about the history of evolutionary biology, you may know that after the rediscovery of Mendel’s work in 1900 there was a heated debate between the “biometricians” (e.g., Galton and Pearson) and the “Mendelians” (e.g., de Vries, Correns, Bateson, and Morgan). Biometricians asserted that the really important variation in evolution didn’t follow Mendelian rules. Height, weight, skin color, and similar traits seemed to

Human biochemical genetics

A positive temperature coefficient is the term which has been used to indicate that an increase in solubility occurs as the temperature is raised, whereas a negative coefficient indicates a decrease in solubility with rise in temperature.

Effect of Temperature

The hypothesis that traits closely associated with fitness will generally possess lower heritabilities than traits more loosely connected with fitness is tested using 1120 narrow sense heritability estimates for wild, outbred animal populations, collected from the published record. Our results indicate that life history traits generally possess lower heritabilities than morphological traits, and that the means, medians, and cumulative frequency distributions of behavioural and physiological traits are intermediate between life history and morphological traits. These findings are consistent with popular interpretations of Fisher's (1930, 1958) Fundamental Theorem of Natural Selection, and Falconer (1960, 1981), but also indicate that high heritabilities are maintained within natural populations even for traits believed to be under strong selection. It is also found that the heritability of morphological traits is significantly lower for ectotherms than it is for endotherms which may in part be a result of the strong correlation between life history and body size for many ectotherms.

/pdf/natural-selection-and-the-heritability-of-fitness-components-4he3tb91vh.pdf

Natural selection and the heritability of fitness components

Preface. Selected Atomic Weights. Customary Metric Conversion Factors. 1. Water Quality and Aquaculture: Preliminary Considerations. 2. Ecology of Aquaculture Ponds. 3. Water Quality Requirements. 4. Water Use. 5. Liming. 6. Fertilization. 7. Aeration. 8. Water Circulation. 9. Turbidity and Appearance of Water. 10. Aquatic Weed Control. 11. Off-Flavors and Harmful Algae. 12. Pollution. 13. Chemical, Physical, and Biological Treatments. 14. Waste Management. 15. Measurement of Water Quality. 16. Sustainability and Environmental Issues. References. Index.

Pond aquaculture water quality management

The evolution of intrinsic growth rate has received less attention than other life history traits, and has been studied differently in plants, homoiotherms, and poikilotherms. The benefits of rapid growth are obvious, so the problems is to explain the costs and tradeoffs that cause organisms to grow below their physiological maximum. Four prevailing themes emerge from the literature: (1) slow growth is adaptive for dealing with nutrient stress, (2) the tradeoff between growth rate and development limits growth in species that require mature function early in life, (3) rapid growth evolves when a minimum size must be reached quickly, such as for sexual maturation or overwintering, and (4) rapid growth may evolve to compensate for slowed growth owing to environmental conditions. Evidence for each of these themes is detailed for plants, homoiotherms, and poikilotherms. In addition, empirical evidence is reviewed for costs of rapid growth, including increased fluctuating asymmetry, reduced immune capacity, and reduced ability to respond to environmental stress.

https://www.biology.ucr.edu/people/postdocs/reprints/01arendt_qrb%20.pdf

Bjarne Gjerde

Papers

Genetic improvement of farmed tilapias: the growth performance of eight strains of Oreochromis niloticus tested in different farm environments

Growth and reproduction in fish and shellfish

Feed intake, growth and feed utilization of offspring from wild and selected Atlantic salmon (Salmo salar)

Genetic origin of Norwegian farmed Atlantic salmon

Body traits in rainbow trout: II. Estimates of heritabilities and of phenotypic and genetic correlations