How the giraffe got its neck (Introduction)

by David Turell @, Thursday, October 08, 2015, 00:05 (3116 days ago)

Tracing back, the ancestors had long necks which then elongated further by enlarging the seven neck vertebrae. All of us mammals have seven vertebrae:-http://www.livescience.com/52407-how-giraffe-got-its-neck.html?cmpid=NL_LS_weekly_2015-10-07-"The researchers focused on the third cervical vertebra of each species, and compared the modern animals' vertebrae with those of their ancestors. Giraffes, like humans, have seven cervical vertebrae, but the giraffe's vertebrae are large, measuring up to 10 inches (25.4 centimeters) long.-"After Canthumeryx, the ancestor that lived 16 million years ago, the family tree split into two branches. The researchers found that on one branch, four species had evolved shorter necks over time.-***-"A key point came about 7 million years ago, when the front side of each vertebra began getting longer, contributing to the neck lengthening in species such as Samotherium major, which is a member of the modern giraffe family.-"Then, about 1 million years ago, in another species, the back part of each vertebra lengthened, which also contributed to the modern giraffe's neck.-"In other words, the fossil trail shows that the neck "elongated disproportionally," Solounias said. "In the beginning you had an anterior [front] elongation, and then later, you had a posterior [back] elongation.'"


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