Google Doodle today paid tribute to Sudan, the last surviving male northern white rhinoceros.

The Doodle was meant to celebrate the anniversary of the day in 2009 when Sudan and three other northern white rhinos arrived at their new home at the Ol Pejeta Conservancy in Kenya. 

A year later, he was taken to Dvůr Králové Zoo in Czechoslovakia (now the Czeck Republic), the only zoo in the world where northern white rhinos have successfully given birth. There, Sudan fathered three calves and became the grandfather of one.

The four were transferred back to the Ol Pejeta Conservancy in 2009 after the northern white rhino was declared extinct in the wild. Conservationists had hoped that being in their natural Kenyan habitat would encourage breeding among the rhinos, but those efforts were unsuccessful.

Sudan spent the final years of his life with his daughter Najin and granddaughter Fatu before being euthanized in 2018 at the age of 45.

Despite Sudan’s death, scientists are hoping to harness vitro fertilization techniques to save the subspecies. But for now, Najin and Fatu are the world’s final two northern white rhinoceros.