Tall Girl

The age of the mother also has some influence on the her child's height. Studies in modern times have observed a gradual increase in height with maternal age.
The precise relationship between genetics and environment is complex and uncertain. Human height is 60%-80% heritable, according to several twin studies and has been considered polygenic since the Mendelian-biometrician debate a hundred years ago. The only gene so far attributed with normal height variation is HMGA2. This is only one of many, as each copy of the allele concerned confers an additional 0.4 cm (0.16 in) accounting for just 0.3% of population variance.
The Nilotic peoples of Sudan such as the Dinka have been described as the tallest in the world, with the males in some communities having average heights of 1.9 m (6 ft 3 in) and females at 1.8 m (5 ft 11 in). The Dinka are characterized as having long legs, narrow bodies and short trunks, an adaptation to hot weather. However, a 1995 study casts doubt on the claim of extraordinary height in Dinka, which after studying the average height of Dinka males in one location, listed the actual number as 1.76 m (5 ft 9 1⁄2 in). Males in the Dinaric Alps have an average height of 1.85 m (6 ft 1 in).