United States Marine Corps Staff Sgt. Jason Itro yells at recruit Nancy Carbins January 15, 2003 after she grabbed another recruit in the pool in an attempt to stay afloat during swim training at the Combat Pool on Parris Island, SC. Under the watchful eyes of swim instructors, recruits are required to swim in full gear and learn limited strokes and breathing to stay afloat. Carbins broke a major rule by grabbing another recruit and submerging them both. (Photo by Stephen Morton/Getty Images)

The Census of Marine Life was a global network of researchers in more than 80 nations engaged in a 10-year scientific initiative to assess and explain the diversity, distribution, and abundance of life in the oceans. The world's first comprehensive Census of Marine Life — past, present, and future — was released in 2010 in London.

First graders attend a festive ceremony to mark the start of another school year in Slaviansk, September 1, 2014. September 1 marks the start of a new academic year for students in Ukraine. (Photo by Gleb Garanich/Reuters)

Model Juliana Paesthe (C) of Viradouro samba school participates in the annual carnival parade in Rio de Janeiro's Sambadrome, February 15, 2015. (Photo by Ricardo Moraes/Reuters)

Homeless man Alonzo Harrison, 47, takes a nap on a bench at Pershing Square decorated with Christmas lights in the background on Monday, December 4, 2017, in Los Angeles. A homeless crisis of unprecedented proportions is rocking the West Coast, and its victims are being left behind by the very things that mark the region's success: soaring housing costs, rock-bottom vacancy rates and a roaring economy that waits for no one. (Photo by Jae C. Hong/AP Photo)

Let the fun begin. Revellers carry their belongings as they arrive at Worthy Farm in Somerset for the Glastonbury Festival, Britain, June 22, 2016. Around 180,000 are expected to attend. (Photo by Ben Birchall/PA Wire)