This combination of April 15, 2013 and April 2, 2014 photos show a police officer clearing Boylston Street following a bomb blast near the finish line of the 2013 Boston Marathon, and pedestrians crossing at the same corner nearly a year later in Boston. (Photo by Charles Krupa/AP Photo)

Global wildlife populations will decline by 67% by 2020 unless urgent action is taken to reduce human impact on species and ecosystems, warns the biennial Living Planet Index report from WWF (World Wide Fund for Nature) and ZSL (Zoological Society of London). From elephants to eels, here are some of the wildlife populations most affected by human activity. Here: The maned wolf is among the large mammals in the Brazilian Cerrado that are threatened by the increasing conversion of grasslands into farmland for grazing and growing crops. (Photo by Ben Cranke/Nature Picture Library/Alamy Stock Photo)

India's Central Reserve Police Force personnel take part in a rehearsal for the Republic Day parade on a cold winter morning in New Delhi January 8, 2014. (Photo by Ahmad Masood/Reuters)

Maria Menounos and Derek Hough sit courtside as the Celtics play the Lakers in Los Angeles, March 2012. (Photo by Lucy Nicholson/Reuters)

Savita, a street performer, helps her dog to balance on empty tin containers as they perform at a roadside in Ahmedabad September 7, 2014. (Photo by Amit Dave/Reuters)

Holocaust survivors are seen backstage during a beauty contest for survivors of the Nazi genocide in the northern Israeli city of Haifa, November 24, 2015. Thirteen women took part in the third annual beauty contest for Holocaust survivors in Israel on Tuesday. (Photo by Amir Cohen/Reuters)

Spectators pass through security screening ahead of the New Year's Eve celebration in Times Square in New York, on Sunday, December 31, 2017. (Photo by Peter Morgan/AP Photo)

Liusba Grajales, left, puts makeup on her daughter Ainhoa as her partner Lisset Diaz Vallejo gets ready as they prepare to get married in Santa Clara, Cuba, Friday, October 21, 2022. The couple, which has been together for seven years, is one of the first to make the decision to get legally married in Cuba following the new Family Code, which opened up everything from equal marriage to surrogate mothers. (Photo by Ismael Francisco/AP Photo)