Ecology, Evolution and Genetics. Solutions to many of the world's most pressing environmental issues require a basic understanding of nature at the organismal, population and ecosystems level.
Average. On average, women start to show around the fourth month of pregnancy, between weeks 14 and 17. By week 17 the uterus usually has expanded to just an inch and a half below the navel, making the pregnancy more obvious.
Depending on the breed of the heifer, most heifers will start to show the first signs of heat when they are between 9 and 22 months of age. 1  The rate of sexual maturity or puberty is determinate of genes and breeding.