Imagine living in the sea where it is permanently dark, cold, and food is hard to find. For many animals at depth, it may be weeks to months between meals. If you find something to eat, you have to hang on to it. This is why so many deep-sea fishes have lots of big teeth. This dragonfish, spotted off the coast of Australia, even has teeth on its tongue. They would be terrifying animals ... if they weren’t the size of a banana. (Photo by Julian Finn/Museum Victoria)

In this photo taken Thursday January 17, 2013, sled dogs Poncho, left, and his blind brother Gonzo are hooked up for a run at the Muddy Paw Sled Dog Kennel, in Jefferson, N.H. Poncho has taken to helping his blind brother on regular runs. (Photo by Jim Cole/AP Photo)

The People of Mah Meri tribe at home at Pulau Carey village on December 03, 2016 in Selangor, Malaysia. The Mah Meri people are one 18 tribes of Orang Asal (indigenous people) living in west Malaysia. The Mah Meri are know for thei wood carvings and also for the richness of their songs and dances. (Photo by Yuli Seperi/Sijori Images/Barcroft India)

In this April 4, 2017 photo, Zoologist Martha Llanes caresses baby chimpanzee Anuma II, left, while Ada hangs on to her leg, at Llanes' apartment in Havana, Cuba. She has forgiven them every transgression. It's hard to stay angry at a baby chimpanzee when it clambers up your leg and into your arms and plants a kiss on your cheek in a plea for forgiveness. (Photo by Ramon Espinosa/AP Photo)

Hindu devotees, their bodies pierced with lemon and paladai, or bowl with a spout mainly used to feed milk to infants, wait to participate in a procession to mark Shivratri, or the night of Shiva, in Chennai, India, Wednesday, February 18, 2015. Such processions are held as an offering and show of devotion by devotees on the day dedicated to the worship of Lord Shiva, the Hindu god of destruction. (Photo by Arun Sankar K./AP Photo)

In this September 30, 2017 photo, people perform “transvestite target practice” to protest the killings of transvestite prostitutes during the annual LGBQT march in Asuncion, Paraguay. Advocacy groups fear the stigma and attacks against the LGBQT community could get worse now that the country's education minister has banned classes about sexual diversity in schools and even volunteered to help burn all books related to the subject. (Photo by Jorge Saenz/AP Photo)

In this February 1, 2017 photo, Anjali Lama, a transgender model from Nepal, looks at her mobile phone backstage during Lakme Fashion week in Mumbai, India. Growing up as the fifth son in a poor farming family in rural Nepal the dream to be a fashion model came late in life.(Photo by Rafiq Maqbool/AP Photo)

A crocodile at a zoo in the southern Taiwan city of Kaohsiung holds the forearm of a zoo veterinarian in its teeth, April 2007. Surgeons in Taiwan have reattached a vet's arm, after it was bitten off by a crocodile as he tried to give it an anaesthetic injection. His attacker is one of a pair of Nile crocodiles kept at Shoushan zoo. Nile crocodiles are known to be man-eaters, but are also listed as an endangered species. (Photo by Frank Lin/Reuters)