Determinants of individual growth

Transcription

1 Determinants of individual growth 2 populations with different body size = an environmental effect 2 pop. in the same environment 1 pop. in 2 environments Sorci, Clobert, Bélichon (1996) Journal of Animal Ecology 65:

2 Determinants of individual growth Density dependence (competition) Experimental density manipulation Density Competition Growth Yearling body size Massot, Clobert, Pilorge, Lecomte, Barbault (1992) Ecology 73: y. old female body size

3 Determinants of individual growth Female growth > Male growth Yearly variation High family resemblances in the first month of growth (genetic, prenatal or postnatal determinants) Prenatal stress Prenatal temperature Postnatal humidity Postnatal food Juvenile growth Juvenile growth Juvenile growth Juvenile growth Le Galliard, Massot, et al. (2006) Journal of Evolutionary Biology 19: Lorenzon, Clobert et al. (2001) Evolution 55:

4 Determinants of individual growth Litter sex ratio may influence fitness due to hormonal interaction between foetuses Male biased litters Growth of juvenile females Body size of females at maturity Uller, Massot, et al. (2004) Evolution 58:

5 Determinants of individual growth characteristics at birth Clobert, Oppliger, Sorci, Ernande, Swallow, Garland (2000) Functional Ecology 14:

6 Determinants of individual growth Compensatory processes (negative feedbacks) Growth Body size Fecundity Growth Trade-off Upper limit to body size Competition Growth Growth

7 Ontogeny and age structure Size distribution influenced by age distribution and population sex ratio Fitze, Le Galliard (2005) Ecology Letters 11: Pilorge, Castanet (1981) Acta Oecologica - Oecologia Generalis 2:3-16

8 Maternal age effect Maternal age effect dependent on sex, habitat and maternal body size! Meylan,Clobert, Montes, Haussy, Cubo, Massot (en préparation)

9 Size-dependent mortality Juvenile survival rate Juvenile body size Mugabo, Marquis, Le Galliard (en preparation)

10 Size-dependent dispersal Size-dependent dispersal with mother-offspring competition Cote, Clobert, Fitze (2007) PNAS 104: Cote, Clobert(2007) Ecology Letters 10:

11 Size-dependent dispersal Higher growth rate in juveniles colonizing empty patches Le Galliard, Ferrière, et al. (2005) Journal of Animal Ecology 74:

12 Interaction with other species Competition with a frog Growth Overlap in prey size with a common frog Pilorge (1982) Amphibia-Reptilia 3:27-31

13 Interaction with other species Ectoparasites on the mother => Maternal effect on growth of offspring females Sorci, Clobert (1995) Journal of Evolutionary Biology 8:

14 Interaction with abiotic factors Humidity Activity Growth Body size Lorenzon, Clobert, Oppliger, John-Alder (1999) Oecologia 118:

15 Effects of Body size in the Common lizard

16 Effects on intraspecific relationships Allometry of individual performances A classical fitness advantage in reptiles Body size Litter size Stronger relationship in older females Meylan,Clobert, Montes, Haussy, Cubo, Massot (en préparation) Eizaguirre, Laloi et al. (2007) Proceeding of the Royal Society B 274: Massot, Clobert, Pilorge, Lecomte, Barbault (1992) Ecology 73: Pilorge (1987) Herpetologica 43: Pilorge, Xavier, Barbault (1983) Holarctic Ecology 6:

17 Effects on intraspecific relationships Allometry of individual performances Another classical fitness advantage in reptiles Body size Age at maturity Massot (unpublished data)

18 Effects on intraspecific relationships Allometry of individual performances Reproductive system 2-5 fathers within litters in approximately 50% of females Reproductive failures more frequent in the longest monoandrous females Eizaguirre, Laloi et al. (2007) Proceeding of the Royal Society B 274:

19 Effects on intraspecific relationships Allometry of individual performances but relationship sensitive to juvenile sex, maternal feeding and year Sorci, Clobert (1997) Evolutionary Ecology 11: Meylan, Clobert (2004) Physiological and Biochemical Zoology 77:

20 Effects on intraspecific relationships Allometry of individual performances Body size Endurance Survival But mainly in small individuals Positive relationship between juvenile size and endurance Le Galliard, Ferrière (2008) Evolutionary Ecology Research 10: Le Galliard, Clobert et al. (2004) Nature 432: Mugabo, Marquis, Le Galliard (en preparation)

21 Effects on intraspecific relationships Maternal effects / individual performances Juvenile endurance negatively correlated with maternal body size Sorci, Swallow, Garland, Clobert (1995) Physiological Zoology 68: Le Galliard, Clobert, et al. (2004) Nature 432: Juvenile endurance not correlated with maternal body size Meylan, Clobert (2004) Physiological and Biochemical Zoology 77: Maternal influence dependent on year or/and population

22 Effects on intraspecific relationships Maternal effects / individual performances Maternal stress Only in large mother Juvenile basking Body size = conditional variable Belliure, Meylan, Clobert (2004) Journal of Experimental Zoology 301A:

23 Effects on intraspecific relationships Maternal effects / individual performances Maternal stress Only in small mother Juvenile activity Body size = conditional variable de Fraipont, Clobert, Alder (2000) Journal of Animal Ecology 69:

24 Effects on other species Body size Prey size Competition with a frog Overlap in prey size with a common frog Pilorge (1982) Amphibia-Reptilia 3:27-31 Massot, Clobert (unpublished data)

25 Climate change & Body size in the Common lizard

26 Climate warming in the study area (daily maximum temperatures) Temperature ( C) August June May April Warming in 4 of the 6 months of the activity season : August r=0.49 P= (without the heatwave 2003) June r=0.53 P= May r=0.59 P= April r=0.38 P= Significant warming only in June during the study period (other months cannot explain observed trends) Independent temperatures during the study period Chamaillé-Jammes, Massot, Aragon, Clobert (2006) Global Change Biology 12: Massot, Clobert, Ferrière (2008) Global Change Biology 14:

27 Effects of climate warming from individual to metapopulation Climate warming physiology Individual behaviour phenology Individual traits, fitness, dispersal evolution Population dynamics, composition relations between populations

28 Integrative approach Climate warming physiology Individual Laying date behaviour phenology Body size Litter size Survival Individual traits, fitness, dispersal Population evolution Dorsal morphs Dispersal relations between populations dynamics, composition

29 Integrative approach Climate warming physiology Individual behaviour phenology Body size a key parameter Individual traits, fitness, dispersal evolution Population dynamics, composition relations between populations

30 Body size Body size P<0,0001 for each study sites + 28 % in yearlings! until mid-90s Positive relationships between body size in yearlings and temperature in June / August Chamaillé-Jammes, Massot, Aragon, Clobert (2006) Global Change Biology 12:

31 Body size Climate warming still moderate = a series of good activity seasons / usual temperature variations performance T l T s T p T preferendum T stress T lethal Expectation of a decrease in body size with a stronger climate warming temperature Chamaillé-Jammes, Massot, Aragon, Clobert (2006) Global Change Biology 12:

32 Litter size Litter size in 3 sites (P<0,0001) Relationship between Litter size and Body size Litter size in 1 site (P=0,047) Climate warming still moderate = a series of good activity seasons / usual temperature variations performance T l T s T p T preferendum T stress T lethal Expectation of a decrease in litter size with a stronger climate warming (CHA?) temperature Chamaillé-Jammes, Massot, Aragon, Clobert (2006) Global Change Biology 12:

33 Cohort effects Climate conditions may have delayed life history effects (Stenseth et al Science 297: ) Performance Intergenerational effects on reproductive performances? (litter size, offspring size, survival) t t+1 t+2 année time We found effects of rainfall, but not of temperature Marquis, Massot, Le Galliard (2008) Ecology 89:

34 Cohort effects F1 Rainfall during gestation - Offspring body size + - Offspring fecundity Offspring survival (independently of offspring body size) F2 + Offspring body size (independently of fecundity) Marquis, Massot, Le Galliard (2008) Ecology 89: Complexity

35 Important messages

36 Body size is a key parameter! Body size = target variable " Effects from other individuals, other populations, others species, abiotic factors! Body size = conditional variable " Allometric relationships mediate a large number of individual and population processes! Body size = influential variable " Effects on other individuals, other populations, others species, abiotic factors! Many relationships with body size! " Ignore body size in an investigation/study/analysis is dangerous " Body size = Integrative parameter of individual quality/history and population functioning

37 Body size is a key parameter! Impacts of Climate change " Dramatic change of body size in populations " Consequence on fecundity " Delayed effects (until a grand-maternal effect on body size!) Population regulation Metapopulation persistence Colonising ability! Cascade effects Warming Body size Fecundity Dispersal Density dependence Age at maturity Sex-ratio Population Female mortality Litter size vortex Sexual harassment