This high pressure is needed to force blood up their long neck to their brain. To maintain the pressure, a giraffe's heart is two feet long, weighs 25 pounds and has walls three inches thick. The tallest giraffe on record lived in a London zoo and attained a height of 20 feet. Our giraffes fall into a rarer group called Masai, which have irregular blotchy patterning. In the wild, giraffes live about 26 years.
Females are able to reproduce up to age twenty.
Giraffes will breed over most of their range at any time of the year. Usually, mothers give birth to a single calf, but twins are known to occur. A newborn calf can usually stand as soon as twenty minutes after birth and will begin to nurse in about an hour. The calf will nurse for up to 13 months and may remain with the mother for another 2-3 months after weaning. Active mostly in the evening and early morning, they often rest during the heat of the day.