Dhruva Aliman does a back somersault as he dismounts from a slackline on the beach at Santa Monica, California on October 19, 2014. Slackline is a balance sport where a line of webbing is adjusted at different levels of tension between two anchor points and participants (called slackers) perform tricks and stunts including somersaults. (Photo by Mark Ralston/AFP Photo)

A P-51 Mustang named “Charlotte's Chariot” from the Southern Heritage Air Foundation flies past a cloud of smoke and fire from a nearby battle reenactment during the Wings Over Houston Airshow in Houston, on Saturday, November 1, 2014. Battle reenactments are part of the yearly show held at Ellington Airport. (Photo by Kar Hlava/AP Photo/Bay Area Citizen)

Wedges of an orange generate enough current and electrical juice – 3.5 volts – to power an LED. The fruit’s citric acid helps electrons flow from galvanized nails to copper wire in this 14-hour exposure. This image was published in September’s Visions of Earth, a trio of photos that appear in each issue of National Geographic. (Photo by Caleb Charland/National Geographic)

This tiny hedgehog is in a prickly position as hes unable to grow spikes, leaving him needing round-the-clock care. The woodland critter was found with no spikes and has been taken in by a family hoping to nurse him back to health so he can be released into the wild. Named Mr Prickleless, the hedgehog was rescued by Dina Nixon and her daughter Jennifer, 25, after being taken into a rescue centre in December last year. It is not known what happened to his spikes, but Dina has vowed that if they ever do return he will be returned to the wild. But for now the hedgehog has taken shelter in a rabbit hutch in her garden. (Photo by Caters News Agency)

“Shortly after he arrived, Van Agtmael witnessed the aftermath of this suicide bombing at a cafe that soldiers frequented in Mosul. Nine people died and 23 were wounded”. (Photo and caption by Van Agtmael/Harrison Jacobs/Magnum Photos)

In this photograph taken on April 16, 2014, a veterinary staff member of the Sumatran Orangutan Conservation Programme center conducts medical examinations on a 14-year-old male orangutan found with air gun metal pellets embedded in his body in Sibolangit district in northern Sumatra island. (Photo by Sutanta Aditya/AFP Photo)

A woman lies injured after an incident on Westminster Bridge in London on Wednesday, March 22, 2017. A police officer has been stabbed near to the British Parliament and the alleged assailant shot by armed police. Scotland Yard report they have been called to an incident on Westminster Bridge where several people have been injured by a car. (Photo by Toby Melville/Reuters)

Five year old George holds an orange to feed the Owl butterflies at the Natural History Museum in London, Thursday, March 30, 2017. Hundreds of tropical butterflies were released to launch the Natural History Museum's Sensational Butterflies exhibition, starting for the public on March 31, 2017. (Photo by Frank Augstein/AP Photo)