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.
Some bull calves can show libido when they reach 6 to 8 months of age. Some won't show it until a month or so later. Most bulls should be showing libido by the time they are 12 months old. However, all this depends on the breed and each individual bull.