A dog known as “Menswear Dog”, a 5-year-old Shiba Inu, poses for photos during the 24th Annual Tompkins Square Halloween Dog Parade in New York October 25, 2014. Hundreds of dog owners dress their dogs and compete for fun and prizes during the parade. (Photo by Carlo Allegri/Reuters)

A bulldog dressed as Marilyn Monroe poses for a photograph during the annual Tompkins Square Halloween Dog Parade in the Manhattan borough of New York City, October 24, 2015. (Photo by Stephanie Keith/Reuters)

David Nicholson, 21, surfs as "The Mask" during the ZJ Boarding House Haunted Heats Halloween Surf Contest in Santa Monica, California, United States, October 31, 2015. (Photo by Lucy Nicholson/Reuters)

In this composite image (L-R top row) Dok Haze, Douglas Child as Camp Dracula, Mongolian Laughing Boy, Tony Walls, Asia Sawika as Anastasia, (L-R bottom row) zombie bass guitar player Ozzy Jackson, sword swallower Hannibal Hellmurto, pickled person, Zoe Olivia Ellis and The Sinister Sisters, Steph Bates (L) and Steph Randall (R) pose for a photograph prior to a rehearsal of the Circus of Horrors' latest show The Night of the Zombie at the Wookey Hole Caves Theatre near Wells on October 23, 2014 in Somerset, England. (Photo by Matt Cardy/Getty Images)

David Nickerson, 24, rides a wave dressed as Mrs Doubtfire during the 7th annual ZJ Boarding House Haunted Heats Halloween surf contest. (Photo by Lucy Nicholson/Reuters)

A dog dressed in a costume takes part in the Pet's Halloween Day parade at Abtao Park in San Isidro, Lima, October 31, 2016. (Photo by Guadalupe Pardo/Reuters)

In a north London hospital, scientists are growing noses, ears and blood vessels in the laboratory in a bold attempt to make body parts using stem cells. It is among several labs around the world, including in the U.S., that are working on the futuristic idea of growing custom-made organs in the lab. (Photo by Matt Dunham/AP Photo)