Meet the Clydesdale. The Clydesdale breed once almost faced extinction. Even though there is little practical use for heavy horses today because their muscle power has been replaced by machinery, breeders and enthusiasts have ensured that the breed is increasing, rather diminishing in numbers.
1 Over the three decades, the twin birth rate rose by 76 percent, from 18.9 to 33.2 per 1,000 births (or from 1.9 percent to 3.3 percent of all births) (Figure 1). 2  Increases in the twin birth rate averaged more than 2 percent a year from 1980 through 2004 (peaking at more than 4 percent from 1995 to 1998).
Twin moms each give birth to second set of twins. Twin sisters Kelli Wall, left, and Kerri Bunker are shown in this undated photo provided by Kerri Bunker. SALT LAKE CITY â Identical twin sisters from Utah each recently gave birth to identical twins â again. Kerri Bunker and Kelli Wall delivered twins within weeks of each other at a hospital in Orem, south of Salt Lake City. Years ago, they gave birth to their first sets of twins, now 4- and 5-year-olds, at the same hospital a few months apart. Bunkerâs newest twins arrived Feb. 13. Wallâs youngest twins were born about three weeks earlier.