Trade-offs between reproductive and somatic (storage) investments in animals: a comparative test of the Van Noordwijk and De Jong model

Authors
Citation
Ds. Glazier, Trade-offs between reproductive and somatic (storage) investments in animals: a comparative test of the Van Noordwijk and De Jong model, EVOL ECOL, 13(6), 1999, pp. 539-555
Citations number
149
Language
INGLESE
art.tipo
Review
Categorie Soggetti
Environment/Ecology
Journal title
EVOLUTIONARY ECOLOGY
ISSN journal
0269-7653 → ACNP
Volume
13
Issue
6
Year of publication
1999
Pages
539 - 555
Database
ISI
SICI code
0269-7653(1999)13:6<539:TBRAS(>2.0.ZU;2-Y
Abstract
Classical life-history theory predicts 'trade-offs' between reproductive an d somatic investments. However, empirical studies have shown that intraspec ific phenotypic correlations between these two resource investments are oft en positive or nonsignificant, rather than negative as predicted. The model of Van Noordwijk and De Jong (1986) was proposed to explain these unexpect ed results. According to their model, positive correlations between reprodu ctive and somatic investments will result if individual variation in resour ce acquisition exceeds that of resource allocation, whereas negative correl ations will result if individual variation in resource allocation exceeds t hat of resource acquisition. To test this model, I used body storage/condit ion as an index of somatic investment because it is usually strongly relate d to level of resource acquisition. I predicted that laboratory studies sho uld more often show negative correlations between reproductive and somatic investments than field studies, because individual variation in resource ac quisition is expected to be lower in controlled laboratory environments tha n in variable natural environments. A literature review revealed that corre lations between somatic (storage) investment and reproductive investment (e stimated as clutch/litter mass, number of offspring per clutch/litter, or n umber of clutches/litters) among conspecific breeding female animals are mo re often positive (15 species) or nonsignificant (17 species) than negative (6 species). Moreover, as expected, five of six negative correlations were observed in laboratory studies, whereas 13 of 15 positive correlations wer e observed in field studies. It is concluded that future empirical and theo retical work on life histories should consider individual variation in both resource acquisition and allocation and the interaction between the two.