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Explore the evolutionary theories of DEB, central metabolism, and symbiogenesis by Bas Kooijman. Understand the dynamics of internalization, reserve capacity, and the emergence of life stages. Dive deep into the interplay of energy generation, substrate allocation, and growth strategies.
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Evolution in the context of DEB theory Bas Kooijman Dept theoretical biology Vrije Universiteit Amsterdam Bas@bio.vu.nl http://www.bio.vu.nl/thb/ Wimereu, 2011/06/14
Mouse goes preying 2.1c On the island Gough, the house mouse Mus musculus preys on chicks of seabirds, Tristan albatross Diomedea dabbenena Atlantic petrel Pterodroma incerta The bird weights are 250 the mouse weight of 40 g, Mice typically weigh 15 g 99% of these bird species breed on Gough and are now threatened with extinction
Dwarfing in Platyrrhini 8.1.2 180 g Cebidae 130 g Saimiri 200-400 g Saguinus 400-535 g 480-700 g 400-450 g 780-1250 g 700-1000 g 3500 g Callitrix Callimico Cebuella Leontopithecus MYA Mico Aotus 24.8 20.2 Perelman et al 2011 Plos Genetics7, 3, e1001342 Cebus
Altricial & Precocial Finfoots 2.5.2e Heliornis fulica American finfoot Podica senegalensis, African finfoot Heliopais personata, Asian finfoot
Central Metabolism 3.8.2b source polymers monomers waste/source
Evolution of central metabolism 10.2.1 in prokaryotes (= bacteria) 3.8 Ga 2.7 Ga i = inverse ACS = acetyl-CoA Synthase pathway PP = Pentose Phosphate cycle TCA = TriCarboxylic Acid cycle RC = Respiratory Chain Gly = Glycolysis Kooijman, Hengeveld 2005
3 4 5 1 2 prokaryotes 7 plants 9 animals 6 8 Evolution of DEB systems 10.3 internalisation of maintenance as demand process variable structure composition strong homeostasis for structure increase of maintenance costs delay of use of internal substrates installation of maturation program strong homeostasis for reserve Kooijman & Troost 2007 Biol Rev, 82, 1-30 reproduction juvenile embryo + adult specialization of structure
Evolution of DEB systems 10.3a • Start: variable biomass composition, passive uptake • Strong homeostasis stoichiometric constraints • Reserves: delay of use of internalised substrates storage, weak homeostasis • Maintenance requirements: turnover (e.g. active uptake by carriers), regulation • Maintenance from reserve instead of substrate; increase reserve capacity • Control of morphology via maturation; -rule cell cycle • Diversification of assimilation (litho- photo- heterotrophy) Eukaryotisation: heterotrophic start; unique event? • Syntrophy & compartmentalisation: mitochondria, genome reorganisation • Phagocytosis, plastids (acquisition of phototrophy) • Animal trajectory: biotrophy • Reduction of number of reserves • Emergence of life stages • Further increase of maintenance costs • Further increase of reserve capacity • Socialisation • Supply demand systems • Plant trajectory: site fixation • Differentiation of root and shoot • Emergence of life stages • Increase of metabolic flexibility (draught) • Nutrient acquisition via transpiration • Symbioses with animals, fungi, bacteria • (e.g. re-mineralisation leaf litter, pollination)
Symbiogenesis 10.4g 2.7 Ga 2.1 Ga 1.27 Ga phagocytosis
Symbiogenesis 10.4p • symbioses: fundamental organisation of life based on syntrophy • ranges from weak to strong interactions; basis of biodiversity • symbiogenesis: evolution of eukaryotes (mitochondria, plastids) • DEB model is closed under symbiogenesis: • it is possible to model symbiogenesis of two initially independently • living populations that follow the DEB rules by incremental changes • of parameter values such that a single population emerges that • again follows the DEB rules • essential property for models that apply to all organisms • Kooijman, Auger, Poggiale, Kooi 2003 • Quantitative steps in symbiogenesis and the evolution of homeostasis • Biological Reviews78: 435 - 463
Symbiosis10.4m substrate product
Symbiosis10.4n substrate substrate
Steps in symbiogenesis 10.4o Internalization Free-living, clustering Free-living, homogeneous Reserves merge Structures merge
Syntrophy 9.1.2 Coupling hydrogen & methane production energy generation aspect at aerobic/anaerobic interface ethanol dihydrogen acetate bicarbonate methane dihydrogen Total: methane hydrates >300 m deep, < 8C linked with nutrient supply
Allocation to soma 10.5.2 pop growth rate, d-1 max reprod rate, #d-1 survivor function κ κ κ Frequency distribution of κ among species in the add_my_pet collection: Mean κ = 0.75, but optimum is κ = 0.5 Lika et al 2011 J. Sea Res,to appear