Four red cell enzyme systems were studied in Malaysian mothers and their newborn belonging to three racial groups, the Malays, Indians and Chinese. No significant heterogeneity was observed in the distribution of phosphoglucomutase (PGM1), adenosine deaminase (ADA), 6-phosphogluconate dehydrogenase (6PGD) and acid phosphatase (AP) phenotypes between mothers and their newborn of the three groups. Pooled mother and child acid phosphatase data show a significant heterogeneity between the Malays and Chinese, and between the Malays and Indians. This is comparable to previous studies conducted. For the placental phosphoglucomutase (PGM3) system, a significant heterogeneity was observed between the Chinese and Malays only. No significant heterogeneity was detected in the distribution of PGM1, ADA and 6PGD phenotypes among Malays, Chinese and Indians.
Brain size varies greatly at all taxonomic levels. Feeding ecology, life history and sexual selection have been proposed as key components in generating contemporary diversity in brain size across vertebrates. Analyses of brain size evolution have, however, been limited to lineages where males predominantly compete for mating and females choose mates. Here, we present the first original data set of brain sizes in pipefishes and seahorses (Syngnathidae) a group in which intense female mating competition occurs in many species. After controlling for the effect of shared ancestry and overall body size, brain size was positively correlated with relative snout length. Moreover, we found that females, on average, had 4.3% heavier brains than males and that polyandrous species demonstrated more pronounced (11.7%) female-biased brain size dimorphism. Our results suggest that adaptations for feeding on mobile prey items and sexual selection in females are important factors in brain size evolution of pipefishes and seahorses. Most importantly, our study supports the idea that sexual selection plays a major role in brain size evolution, regardless of on which sex sexual selection acts stronger.