Did you know that approximately 200 species go extinct every day?

On March 20th, the world’s last male northern white rhino, Sudan, was euthanized, ending his suffering as he faced a cluster of viruses at age 45.

Since Sudan’s birth in 1972, the northern white rhino population has rapidly declined, mostly due to human conflict.

This population, of about 1,000 at the time, was largely concentrated in Sudan, Congo, and the Central African Republic, all countries that were troubled with war at the time.

The Northern White Rhino

The northern white rhino is a subspecies of the southern white rhino, which has increased from a few dozens to more than 20,000 in the wild since the end of the 19th century. However, as of 2008, northern white rhinos no longer could be found in the wild.

The huge animals which weigh in between 1.7 -2.4 tons are actually grey in color as opposed to their cousins, the more common black rhinos. Their name oddly is a misinterpretation of the Dutch ‘wijde’ meaning wide. These animals have much wider mouths for feeding on grass as opposed to the narrower mouths of their darker cousins which helps them access leaves and plants. 

Northern white rhinos were often slaughtered for their meat, horns, or simply used as currency in arms trading. With Sudan’s death, the only remaining survivors are Najin, Sudan’s daughter, and Fatu, his granddaughter.

There have been multiple attempts to produce offspring using stored sperm from northern white rhinos and the two remaining females. However, neither female has been able to carry an offspring to full term.

Can Technology Help?

It is for this reason, that scientists are now looking to in-vitro fertilization to repopulate the northern white rhinos.

In-vitro fertilization is the process by which the female eggs are extracted and combined with a sperm sample within a laboratory. In the case of the northern white rhino, eggs from either Najin or Fatu would be extracted and combined with stored sperm from northern white rhinos. The embryo would then be implanted into a female southern white rhino.

However, although this method sounds simple, a generation derived from the eggs of just two females lacks genetic diversity. Genetic diversity is important because it makes a species more tolerant of environmental change. To address this issue, scientists are working to use frozen cells from Sudan to transform them into stem cells. This allows them to create more sperm and eggs and hopefully conserve the northern white rhino gene pool.

The cost of creating a small herd of northern white rhino using this approach could be US $9 million! There are some who argue that extinction is a natural process and humans aren’t necessarily responsible for the conservation of species. But in the case of the northern white rhino, extinction was a direct result of human activity.

Sources: Washington Post, NYTimes, Guardian, The Atlantic