KENYA -- The world's last male northern white rhino, Sudan, has died after "age-related complications."
Researchers in Kenya said the 45-year-old rhino was euthanized on Monday after he was no longer able to stand.
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The rhino had been part of an ambitious effort to save the subspecies from extinction with the help of the two surviving females.
Sven has also told you about the threat to black rhinos. Jeff Muntefering of the Minnesota Zoo says a severe drought, along with poaching, is contributing to the loss of those rhinos in Namibia.
To see that story, click here.