Scarlet Shiner Brain Abstract

I've made some serious headway boiling down Enrique's thesis for a journal article in the 'zine NeuroReport. Below is the current version of the Abstract, at 300 words. I think that's a decent length for this journal, but in truth I still have to read the author's instructions which I just printed. The title will be something close to, "Sexual Dimorphism In A Teleost Fish's Central Nervous System: Are Dominant Males Smarter?", with authors Stallsmith, Sosa, Eguchi, Suessman.

ABSTRACT
The teleost fish, Lythrurus fasciolaris (scarlet shiner), is known to be both a seasonal breeder and sexually dimorphic. Wild scarlet shiners were collected at intervals throughout the breeding season. Morphological and molecular changes that may underlie sexual dimorphism were examined in three key regions of the brain: the cerebellum, optic tectum and the telencephalon. Allometric analysis of whole brain mass relative to body mass showed that males were significantly more variable (R2 = 0.29) during the breeding season than females (R2 = 0.84). Males were also found to have larger average volumes than females in all three brain regions relative to total brain mass (p<0.01). The quantity and location of NMDA receptors in relation to sex and reproductive status was examined. Four groups were examined: dominant males, non-dominant males, reproductive females and non-reproductive females. At the beginning of the breeding season, dominant male shiners have at least a 3.5-fold higher expression of NMDARs than non-dominant males in all three brain regions (p<0.01). Non-reproductive females had 4-fold higher NMDAR in the cerebellum then reproductive females. At the peak of the breeding season, the telencephalon region of non-reproductive female fish exhibits 3.5-fold higher expression of NMDAR than non-dominant males. Dominant males and reproductive females both exhibit about a 2-fold higher expression than non-dominant males. In the cerebellum, both female groups exhibited a 2-2.5-fold higher expression level of NMDAR than either male group. In the optic tectum, the non-reproductive females showed the highest difference with nearly a 25-fold higher concentration of NMDAR than non-dominant males. Reproductive females exhibited a 10-fold higher level and dominant males an 8-fold higher level. This study suggests that NMDARs undergo both temporal and sex-specific regulation. These findings show quantifiable morphological and molecular changes in sexually dimorphic teleost fish that may correlate to changes in breeding and dominance requirements, with implications for all vertebrates.