Mexico's first cubs born from an artificially inseminated Mexican gray wolf were revealed to the world on Wednesday.

Two cubs were born May 26 to a wolf named Ezita at the Chapuletpec Zoo in Mexico City, zoo officials told the BBC. Ezita was chosen for artificial insemination because she is 11 years old and had a hard time conceiving naturally. The father wolf, named Perkins, came from the Endangered Wolf Center in Eureka, Missouri.

Their births come as Mexican and U.S. officials work to increase the species' population. Hunting, poisoning and trapping nearly wiped out their numbers four decades ago.

Chapuletpec Zoo Director Juan Antonio Rivera said the births mark "the first litter of an endangered species obtained in our country by artificial insemination," the Associated Press reported.

U.S. wildlife officials captured the last five known Mexican gray wolves in the late '70s. They were bred in captivity and released back into the wild in southwestern U.S. in 1998. Mexico began introducing them into the wild in 2011, according to the BBC.

By January of this year, a survey from the U.S. Fish and Wildlife Service located 83 wild Mexican gray wolves in Arizona and New Mexico, the BBC reported. Officials saw more good news in July when the first known litter of cubs was born to wolves released in Mexico.  

But the Mexican gray wolf remains an endangered species in both the U.S. and Mexico.