New River Dolphin Species Discovered

First such discovery since World War I

The new Araguaian river dolphin bears close relation to the Amazon river dolphin, pictured above. (Kevin Schafer/Getty Images)

Researchers working in Brazil have discovered a new species of river dolphin in the Araguaia river basin, according to the journal PLOS ONE.

Why does this matter? Because last time scientists identified a new species of river dolphin, World War I raged and American women still couldn't vote.

Only five known species of river dolphins exist in the world, and they represent some of the world's rarest creatures. Scientists estimate that about 1,000 of the Araguaia dolphins live in the river basin, making them critically endangered.

According to the study, the Araguaia dolphins diverged from the more well-known Amazon river dolphin more than two million years ago, when researchers believe the Araguaia-Tocantins basin separated from the Amazon basin.

The scientists designate the new dolphins as having "high taxonomic distinctness and conservation value" but having "little protection." For starters, the species' low population affords little genetic diversity to combat disease and other environmental risks.

But humans also harm the creatures, with agricultural activities and hydroelectric dams damaging their already-limited environment. Plus, the Araguaian dolphins enjoy fish and often rob the nets of fishermen, who respond by shooting them.

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