Reproductive output

Culture a range of invertebrate species from the major phyla, preferably species with short life cycles. The effects of potential endocrine disrupting chemicals on growth rate, reproductive output, viability of offspring and sex ratio, and the vulnerability of different stages of the life cycle, can then be determined. 

The sensitivity of Mouse-lemurs, as with house mice, shows that complex accessory olfactory (urinary)-related responses convincingly demonstrate the ability of a species to adjust reproductive output to social and environmental conditions. 

Oliveira, P. S. (1997). The ecological function of extrafloral nectaries herbivore deterrence by visiting ants and reproductive output in Caryocar brasiliense (Caryocaraceae). Functional Ecology 11 323-330. 

Levitan, D.R., Influence of body size and population density on fertilization success and reproductive output in a free-spawning invertebrate, Biol. Bull., 181, 261, 1991. 

Of course, the acceptable level of model complexity is closely related to the level of detail of the experimental data. Energy budget approaches are generally most informative when data on body size and reproductive output are available over time for a considerable part of the life cycle. Examples of the application of DEB theory to life cycle toxicity data for single compounds can be found in Jager et al. (2004), Alda Alvarez et al. (2005), and Pieters et al. (2006). More complicated TD approaches require other types of experimental data (e.g., at the molecular level), but should never ignore the level of resource allocation when endpoints such as growth and reproduction are concerned. 

The trophic structure of communities is related to the relative abundance of species that feed on various food items (piscivores, omnivores, detritivores, insectivores, etc.), or have various foraging methods (shredders, scrapers, etc.). These changes in species/ trophic composition may come about by direct or indirect mechanisms. The direct effects involve loss of some species due to an increase in pollution-induced mortality or reduced reproductive output. In... 

Trippel, E., O. Kjesbu and P. Solemmial. Effects of adult age and size structure on reproductive output in marine fishes. In Early Life History and Recruitment in Fish Populations, London, Chapman Hall, pp. 31-55, 1997. 

Natural selection for a particular trait incurs an initial cost to the organism in terms of fitness, or its ability to survive and reproduce. In weeds selected for herbicide resistance, this generalization holds true for biotypes possessing the maternally inherited trait of triazine resistance. This mutation has a detrimental effect on photosynthesis that results in decreased biomass production and reproductive output. However, compensatory interactions of the chloroplast and nuclear genomes may partially overcome reduced productivity. Expression of reduced productivity also appears to be regulated by environmental conditions. Whether similar trends in relative fitness will be found in weeds resistant to other herbicides remains to be examined. 

Fishes have been documented to respond with anti-predator behaviour to cues of both conspecifics as well as ecologically similar heterospecifics with which they co-occur (Chivers and Smith, 1998). The response to heterospecific alarm cues is innate in closely related species, and learned in distantly related species (Smith, 1982 Pollock et al., 2003). Prey warned by conspecific and heterospecific cues may have increased survival over prey that are not warned (Chivers et al., 2002). As well as increasing survival, heterospecific cues are also known to affect the timing of reproduction and the reproductive output of some species (Pollock et al., unpublished data). 

Krah N.M. Logan, B.A. (2010). Loss of PSBS Expression Reduces Vegetative Growth, Reproductive Output, and Light-Limited but not Light-Saturated Photosynthesis in Arabidopsis thaliana (Brassicaceae) Grown in Temperate Light Environments. American Journal of Botany, Vol.97, No.4, (April 2010), pp. 644-649. 

CAERS M, UTTiNG s D, couTTEAU p, MILLIGAN p F and soRGELOos p (2002) Impact of the snpplementation of a docosahexaenoic acid-rich emnlsion on the reproductive output of oyster broodstock, Crassostrea gigas. Marine Biology, 140,1157-1166. 

EHTESHAMI F, CHRISTIANUS A, RAMESHI H, HARMIN S A and SAAD C R (2011) The effects of dietary supplements of polyunsaturated fatty acid on pearl oyster, Pinctada margaritifera L., gonad composition and reproductive output. Aquaculture Research, 42, 613-622. 

Lamberti and co-workers [20] also investigated the chronic toxicity of imidazolium-based ILs towards D. magna. According to their results, all ILs, independent of the anion, negatively affected the reproductive output of the crustaceans, with the lowest number of neonates being produced at the higher concentrations of the IL tested. 

The xenohormesis theory assumes that longevity provides an evolutionary advantage, yet the consequences of mild stress on reproductive output, which is under strong selective constrains, remains unknown... 

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