This study identifies the developmental processes contributing to variation in green-fleshed kiwifruit (Actinidia deliciosa (A. Chev.) C.F. Liang et A.R. Ferguson var. deliciosa) fruit dry matter content (DM) and fresh weight (FW) by comparing genotypes with either high or low final DM. Results are compared with the model for fruit development, the tomato (Solanum lycopersicum L.). Differences in final composition were attributable to a higher rate of starch accumulation from 70 days after anthesis in high DM genotypes, with no other consistent differences in accumulation of soluble sugars or organic acids. High DM genotypes had 70% higher starch content and differed from low DM genotypes in the allocation of carbon between storage and other components. DM was negatively correlated with final fruit FW only in high DM genotypes, whereas starch was a constant proportion of dry weight (DW), suggesting a dilution effect rather than an interaction between fruit size and carbohydrate metabolism. Compared with tomato, the organic acids, particularly quinic acid, contributed more to estimated osmotic pressure during growth in FW than the soluble sugars, regardless of final composition or size. Seed mass per unit FW was highest in high DM genotypes, suggesting a previously unrecognised role for kiwifruit seeds in accumulation of carbohydrate by the pericarp. Anatomical comparisons also identified a role for differences in the packing of the two principal cell types, with an increased frequency of the larger cell type correlated with reduced DM. These genotypes demonstrate that kiwifruit differs from tomato in the role of starch as the principal stored carbohydrate, the reduced importance of dilution by growth in FW and the more minor role of the sugars compared with the organic acids during fruit development.

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Milk composition and the rates of milk consumption by pouch young were examined in free-living allied rock-wallabies, Petrogale assimilis. Milk solids concentrations were approximately 16% (w/w) at 70 days post-partum and increased to about 22% by 170 days when young first left the pouch. By permanent pouch emergence (about 200 days), concentrations had declined and stabilised at about 19%. Milk carbohydrate peaked at 12% (w/v) at 150 days; lipid concentrations averaged 8% (w/w) at 200 days. The subsequent decline in carbohydrates was the main cause of the fall in milk solids. Protein concentrations increased gradually from about 3% (w/v) at 70 days to plateau at 5.5% at about 200 days. Milk consumption rates were measured from 72 to 159 days post-partum with Na-22 turnover. Milk consumption, about 3 mL day(-1) initially, increased to an average of about 15 mL day(-1) by 150 days. The mass gained by a pouch young between 72 and 159 days for each millilitre of milk consumed was not correlated with lactational stage and averaged 0.21 +/- 0.014 (s.e.)g mL(-1).

A biometric analysis of 26 variables measured on 32 adult dugong skulls (16 males, 16 females) describes the nature of the sexual dimorphism present. Further sources of variation include the expected size variation and the continuance of attenuated allometric growth patterns into adulthood.

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