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E x = Expectation of further life:

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E x = Expectation of further life:

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  1. Life tables Age-specific probability statistics Force of mortality qx Survivorship lxly / lx = probability of living from age x to age yFecundity mxRealized fecundity at age x = lxmx Net reproductive rate R0= lxmxGeneration time T= xlxmx Reproductive value vx =  (lt / lx ) mt Ex = Expectation of further life:

  2. Estimated Maximal Instantaneous Rates of Increase (rmax, per capita per day) and Mean Generation Times ( in days) for a Variety of Organisms ___________________________________________________________________ Taxon Species rmax Generation Time (T) ----------------------------------------------------------------------------------------------------- Bacterium Escherichia coli ca. 60.0 0.014 Protozoa Paramecium aurelia 1.24 0.33–0.50 Protozoa Paramecium caudatum 0.94 0.10–0.50 Insect Tribolium confusum 0.120 ca. 80 Insect Calandra oryzae 0.110(.08–.11) 58 Insect Rhizopertha dominica 0.085(.07–.10) ca. 100 Insect Ptinus tectus 0.057 102 Insect Gibbum psylloides 0.034 129 Insect Trigonogenius globulosus 0.032 119 Insect Stethomezium squamosum 0.025 147 Insect Mezium affine 0.022 183 Insect Ptinus fur 0.014 179 Insect Eurostus hilleri 0.010 110 Insect Ptinus sexpunctatus 0.006 215 Insect Niptus hololeucus 0.006 154 Mammal Rattus norwegicus 0.015 150 Mammal Microtus aggrestis 0.013 171 Mammal Canis domesticus 0.009 ca. 1000 Insect Magicicada septendecim 0.001 6050 Mammal Homo sapiens 0.0003 ca. 7000 __________________________________________________________________ _

  3. Inverse relationship between rmax and generation time, T

  4. J - shaped exponential population growth http://www.zo.utexas.edu/courses/THOC/exponential.growth.html

  5. Instantaneous rate of change of N at time tis total births (bN) minus total deaths (dN)dN/dt = bN – dN = (b – d )N = rNNt = N0 ert (integrated version of dN/dt = rN)log Nt = log N0 + log ert = log N0 + rtlog R0 = log 1 + rt (make t = T)r = log l or l = er (l is the finite rate of increase)

  6. Demographic and Environmental Stochasticityrandom walks, especially important in small populationsEvolution of Reproductive TacticsSemelparous versus Interoparous Big Bang versus Repeated Reproduction Reproductive Effort (parental investment) Age of First Reproduction, alpha, a Age of Last Reproduction, omega, v

  7. Mola mola (“Ocean Sunfish”) 200 million eggs! Poppy (Papaver rhoeas) produces only 4 seeds when stressed, but as many as 330,000 under ideal conditions

  8. Indeterminant Layers

  9. Reproductive Effort How much should an organism invest in any given act of reproduction? R. A. Fisher (1930) anticipated this question long ago:‘It would be instructive to know not only by what physiological mechanism a just apportionment is made between the nutriment devoted to the gonads and that devoted to the rest of the parental organism, but also what circumstances in the life history and environment would render profitable the diversion of a greater or lesser share of available resources towards reproduction.’ [Italics added for emphasis.] Ronald A. Fisher

  10. Asplanchna (Rotifer)

  11. Trade-offs between present progeny and expectation of future offspring

  12. Iteroparous organism

  13. Semelparous organism

  14. Patterns in Avian Clutch SizesAltrical versus Precocial

  15. Patterns in Avian Clutch SizesAltrical versus PrecocialNidicolous vs. NidifugousDeterminant vs. Indeterminant Layers N = 5290 Species

  16. Patterns in Avian Clutch SizesOpen Ground Nesters Open Bush Nesters Open Tree Nesters Hole Nesters MALE (From: Martin and Ghalambor 1999)

  17. Patterns in Avian Clutch SizesClassic Experiment: Flickers usually lay 7-8 eggs, but in an egg removal experiment, a female laid 61 eggs in 63 days

  18. Great Tit Parus major David Lack

  19. Parus major

  20. European Starling, Sturnus vulgaris

  21. Chimney Swift, Apus apus

  22. Seabirds (Ashmole) Boobies,Gannets, Gulls, Petrels, Skuas, Terns, Albatrosses Delayed sexual maturity, Small clutch size, Parental care

  23. Albatross Egg Addition Experiment An extra chick added to each of 18 nests a few days after hatching. These nests with two chicks were compared to 18 other natural “control” nests with only one chick. Three months later, only 5 of the 36 experimental chicks survived from the nests with 2 chicks, whereas 12 of the 18 chicks from single chick nests were still alive. Parents could not find food enough to feed two chicks and most starved to death. Diomedea immutabilis

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