Reserve dynamics & social interactions in feeding

1. Reserve dynamics & social interactions in feeding Bas Kooijman Dept theoretical biology Vrije Universiteit Amsterdam Bas@bio.vu.nl http://www.bio.vu.nl/thb Amsterdam 2005/08/15

2. Evolution of DEB systems

3. Reserve dynamics

4. Polymerization inhibition catabolism growth maintenance

5. V usual ontogeny E Structural homeostasis structure reserve Enzymes at interface that mobilize reserves don’t “observe” grain size or substrate conc. No dilution by growth

6. Volume-surface interactions Membrane-mediated transformation rates in isomorphs decrease with length because of transportation distance inactive enzyme active enzyme in binding phase active enzyme in production phase substrate product Cells can “know” their size from the rate at which concentrations of substrate & product change if transformation is by membrane-bound enzymes

7. Protein synthesis 7.5 scaled elongation rate RNA/dry weight, μg.μg-1 Data from Bremer & Dennis 1987 Data from Koch 1970 spec growth rate, h-1 scaled spec growth rate RNA = wRV MV + wRE ME dry weight = wdV MV + wdE ME

8. No age, but size: :These gouramis are from the same nest, they have the same age and lived in the same tankSocial interaction during feeding caused the huge size differenceAge-based models for growth are bound to fail; growth depends on food intake Trichopsis vittatus

9. Rules for feeding

10. Social interaction  Feeding determin expectation length reserve density 1 ind time time 2 ind length reserve density time time