View Images Sperm whales (tail flukes pictured) must contend with getting too much sun, as they can spend hours at the ocean's surface. 
 
 Photograph by Stephen Frink, Getty Images 
 
 It's a good idea to apply sunscreen before heading to the beach if you don't want to burn and blister. But for marine animals like whales, that's not an option. 
 
 Species like sperm whales can spend up to six hours at the ocean's surface in between dives, baking in the sunlight. So how do they protect themselves from a serious case of sunburn? 
 
 It turns out that their bodies have similar defense mechanisms against the sun's ultraviolet (UV) radiation as people, according to a new study published August 30 in the journal Scientific Reports. 
 
 Researchers took more than a hundred skin biopsies from blue, fin, and sperm whales in the Gulf of California (map) from 2007 to 2009. They used crossbows loaded with modified arrowheads to retrieve plugs of skin from the marine mammals. 
 
 They found that blue whales—which have the lightest skin color of the three species—tanned during their summer sojourns before migrating back to their northern feeding grounds. 
 
 Sperm whales didn't tan. Instead, the whales, which can receive an "overdose" of UV radiation during their hours at the ocean's surface, have proteins that protect their cells from UV damage, said study co-author Mark Birch-Machin, a professor of molecular dermatology at Newcastle University in the United Kingdom. 
 
 This process is similar to how human bodies produce antioxidants in response to free radicals, molecules that can cause a lot of genetic and cellular damage. 
 
 And fin whales escaped sun damage thanks to their high levels of melanin—a skin pigment also shown to protect humans from UV radiation. 
 
 Uncharted Territory 
 
 Studying how whales react to UV-radiation damage has never been done before, making the new paper very useful, said Marie-Francoise Van Bressem, a veterinarian specializing in skin diseases in whales, dolphins, and porpoises at the Peruvian Centre for Cetacean Research in Lima. 
 
 Now that the ozone layer that shields Earth from UV radiation is diminishing, "it's important to know what the consequences are for whales and dolphins, especially for vulnerable or endangered species," added Van Bressem, who was not involved in the study. 
 
 Instances of skin disease among whales, dolphins, and porpoises—collectively known as cetaceans—are on the rise, she said. And although it's difficult to tell what causes many of these skin conditions, UV damage is one cause. 
 
 Even though whales have built-in defenses to UV radiation, high exposure can still be harmful. 
 
 "At what point does that [skin lesion] develop into skin cancer?" asked Birch-Machin. No one knows, he said. 
 
 But it's important to figure out, he said, since the skin damage researchers are already seeing could serve as an early warning sign of a serious disease like cancer. (Learn about cancers in beluga whales.) 
 
 Mirrors 
 
 Birch-Machin and colleagues studied the DNA contained in the whales' mitochondria—a cellular organ responsible for powering the cell—in order to assess damage caused by UV radiation. 
 
 "Mitochondrial DNA damage is directly linked to UV exposure, which is why UV ages us," said Birch-Machin. 
 
 "Because the mitochondria are the battery packs of the cell, basically, our batteries run down." 
 
 The research team found that older whales, and whales with less melanin content in their skin—like blue whales—had the greatest level of damage in their mitochondrial DNA (mtDNA). Fin whales, which had the greatest amount of melanin, had the least amount of mtDNA damage. 
 
 Looking at the genetic consequences—or mtDNA damage—of UV radiation has also never been looked at in whales before, Birch-Machin said. And it turns out that this aspect of whale aging mirrors human aging. (Related: "Do Whales Have Culture? Humpbacks Pass on Behavior.") 
 
 Early Warning Signs? 
 
 Birch-Machin would like to figure out whether the skin blistering seen on these whales would develop into skin cancer. 
 
 He and his colleagues would also be interested in looking at other hairless marine mammals, such as walruses, to see if they have similar issues with UV-radiation exposure. 
 
 Although Birch-Machin does a lot of work on UV damage in human skin, he's excited about the prospect of delving further into other species. 
 
 "Whales will reflect the UV dose that the ocean receives," he said. As "floating dosimeters," they are a signal for the health of the ocean. 

 Image caption A blue whale’s head and tail fluke tend to be uniformly grey but their dorsal skin is usually mottled and can be quite pale. 
 
 The way that whales react to sunlight can shed new light on the human ageing process, say researchers. 
 
 Some species react by getting darker with UV exposure in the same way as humans get a tan. 
 
 Others though, protect from themselves from sun burn by turning genes on and off. 
 
 The work, which is published in the journal Scientific Reports, could lead to new anti-ageing treatments in humans. 
 
 For several years now, marine biologists in Mexico have noticed an increasing number of whales in the region with blistered skin as a result of exposure to UV light. 
 
 The sunburnt DNA we find in whales is the same sunburnt DNA we find in humans and that is definitely linked to ageing Prof Mark Birch-Machin, Newcastle University 
 
 Over a three-year period researchers took skin samples from three different species of whales during their annual spring migration, when they move to the sunnier waters of the Gulf of California. 
 
 Warmer Blue 
 
 The scientists found the different species reacted differently to the increase in sunlight. 
 
 Blue whales are the biggest creatures ever to have lived on Earth, and they respond to the Sun by increasing the amount of pigment in their skin, just like humans. 
 
 "When blue whales go on their holidays to the Gulf of California they get a tan the same way we do," Prof Mark Birch-Machin from Newcastle University told BBC News. 
 
 "And that tan protects blue whales from sunburnt DNA." 
 
 Image caption The scientists used crossbows and modified arrows to take skin biopsies from blue whales in the Gulf of California 
 
 According to Prof Birch-Machin, exposure to ultra violet light can damage not just skin but can harm DNA in mitochondria, the battery packs of cells. 
 
 The ability of blue whales to tan in response to UV exposure may be connected to their historic migratory patterns as they move annually from higher to lower latitudes with a greater amount of sunlight. 
 
 Sperm whales have a different approach to the sun, says Prof Birch-Machin. They can spend up to six hours at a time on the surface of the ocean and have far greater exposure to UV light. 
 
 "They are akin to people going for the lobster approach - so changes in pigment aren't going to help them very much as the UV is overwhelming the system," he said. 
 
 Instead of changes in their pigment, the sun triggers a stress response in the genes of these whales, which is similar to our own protective mechanism against sun damage. 
 
 "We saw for the first time evidence of genotoxic pathways being activated in the cells of the whales," said researcher Amy Bowman. 
 
 "This is similar to the damage response caused by free radicals in human skin which is our protective mechanism against sun damage," she added. 
 
 Fins getting better 
 
 The third species the scientists examined were fin whales. These deeply pigmented animals were found to be more resistant to sun damage, with the lowest prevalence of sunburn lesions. 
 
 The researchers hope that by seeing both changes in pigment and changes in genes, the whales may shed some light on the ageing process in humans. 
 
 "The sunburnt DNA we find in whales is the same sunburnt DNA we find in humans and that is definitely linked to ageing," said Prof Birch-Machin. 
 
 "The study shows the interaction of systems that we can then examine further in human research, and that's got implications for anti-ageing and skin cancer approaches," he said. 
 
 And the research, he believes, will be of interest to pharmaceutical companies. 
 
 "They are always on the lookout for what they can see in non-human systems and what they can borrow from that in terms of anti-ageing and this research will certainly help in that," he said. 
 
 The scientists say that further work is required to see if the sun burn that the whales are experiencing turns into skin cancer. They also want to know if an early warning system for the animals can be developed. 
 
 Follow Matt on Twitter. 

 Whales tan too. Just like us, they do it to protect themselves from powerful ultraviolet radiation. 
 
 A study of skin samples taken from blue, fin and sperm whales in Mexico's Gulf of California found that the blue whales show the most obvious tanning effects. Samples were collected between January and June from 2007 to 2009. 
 
 Blue whales migrate annually between the Arctic and the Gulf of California. The team, led by Mark Birch-Machin of Newcastle University, UK, found that their grey skins darken with melanin as ultraviolet radiation intensifies from February to May in the Gulf. 
 
 Birch-Machin and his colleagues also found that damage to mitochondrial DNA in skin cells dropped as the whales' skin darkened, demonstrating that melanin protects them against UV-induced DNA damage, just as it does in humans. 
 
 Perma-tanned 
 
 But neither fin nor sperm whales appeared to change colour noticeably. Unlike blue whales, which migrate annually between the Arctic and Mexico, fin whales live in the Gulf of California all year round, and so are permanently exposed to high UV levels. They had the darkest skin with the highest melanin content. 
 
 Sperm whales spend long periods at the sea surface. For sun-factor protection, they rely on melanin and a substance called heat-shock protein 70, which repairs proteins damaged by UV light. "The amount of UV they're exposed to would overwhelm pigments alone," says Birch-Machin. 
 
 He says the results are the first to show from analysis of DNA and skin that animals rely on pigments too for sun protection. Karina Acevedo-Whitehouse of the Zoological Society of London, reported the first sighting of sunburnt whales three years ago . Birch-Machin says that whether sunburn leads to melanomas in whales – as has been documented in trout – is not known. 
 
 Journal reference: Nature Scientific Reports, DOI: 10.1038/srep02386 
 
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 Different whale species have different ways of protecting themselves from harmful ultraviolet rays from the sun - including tanning, a new study suggests. (John Calambokidis/Canadian Press) 
 
 Some pale whales appear to tan in order to protect themselves from sunburn, a new study says. 
 
 An international team of scientists took mitochondrial DNA samples from blue whales, fin whales and sperm whales to check for genetic damage from ultraviolet rays. 
 
 They found that higher melanin levels in the whale's skin correlated with lower levels of skin lesions and DNA damage, suggesting melanin protects the ocean mammals from sun damage. 
 
 "We found molecular evidence that blue whales increase production of melanin, so this would indicate that they tan," Karina Acevedo Whitehouse, a zoologist from the University of Queretaro in Mexico, and one of the authors of the study published Friday in the journal Scientific Reports. 
 
 "Increasing their pigmentation (tanning) appears to be the way blue whales protect themselves from UV damage." 
 
 They also found that the ability to modify skin pigment — or tan — may be linked to migration patterns. 
 
 Heavy hearts 
 
 Blue whales are believed to be the largest animal to have ever lived on Earth at up to 30 metres in length with hearts that can weigh as much as a car. They're found in every ocean in the world, spending summers in polar waters before migrating toward the Equator for winter. 
 
 The palest of the three study whales, with mottled blue-grey skin, they appear to adjust their pigment as they move from higher UV environments to lower. 
 
 In contrast, fin whales, the blue whale's darker-skinned, stay-at-home cousins, showed a reduced ability to change the level of melanin in their skin. 
 
 Rather, fins maintained higher levels of melanin and had the lowest prevalence of sunburn lesions. 
 
 Sperm whales reacted differently yet. 
 
 These ocean behemoths, with their rounded foreheads and the largest brain of any creature in the world, did not show a spike in melanin production but appeared to respond with increased production of repair genes. 
 
 The researchers believe the difference may lie in their behaviour, which sees sperm whales spend more time on the surface of the water, exposed to UV radiation. 
 
 It suggests that, like humans, they may acclimatize to UV exposure. 
 
 "Whales are the UV dosimeter or barometer of the oceans," co-author Mark Birch-Machin, a professor of molecular dermatology at Newcastle University in the United Kingdom, said in an email. 
 
 No evidence of skin cancer 
 
 Although measures have been put in place, substances released into the environment decades ago continue to deplete the ozone layer in the atmosphere, the study said. 
 
 Other ocean species have been shown to tan, it pointed out, including hammerhead sharks and some fish. 
 
 The researchers did not find evidence of skin cancer in the whale biopsies, but did find DNA damage that could potentially lead to cancer. Birch-Machin said the presence of skin cancer in whales is something he hopes to investigate in the next study. 
 
 Both scientists said environmental changes to their ocean habitat, including climate change, could compromise the whales' ability to protect themselves from UV radiation and other challenges. 
 
 The study is the first to look at the potentially distinct evolution of these whale species to combat the effects of UV radiation. 
 
 It also provides information on changing global climate conditions, information that could potentially be applied to human skin research into aging and skin cancer.
– Researchers have found an unusual way in which whales and humans are similar: we both get suntans. Blue whales, especially, tend to tan to protect themselves from the sun's UV rays, reports the Canadian Press. Essentially, they tan during their summer migrations to ward off dangerous sunburns, as a Newcastle University researcher explains to the BBC: "When blue whales go on their holidays to the Gulf of California they get a tan the same way we do. And that tan protects blue whales from sunburnt DNA." The big blues have lighter skins than the other two types studied—sperm whales and fin whales—and that makes the tanning necessary. Sperm whales, which spend up to six hours at the surface and thus take in big doses of UV rays, take a different human-like tack. Their bodies activate what amount to repair genes, explains National Geographic. "This process is similar to how human bodies produce antioxidants in response to free radicals, molecules that can cause a lot of genetic and cellular damage." The fin whales, meanwhile, have the darkest skin of the three and fared the best in terms of sun damage thanks to their naturally high levels of melanin. (The fins don't migrate, staying in the Gulf of California year-round, notes New Scientist.) Researchers say the findings might not only help them better protect whales and other marine animals from cancer, but they could shed light on skin cancer in humans and the aging process in general. (In other sea-creature news, researchers say the big dolphin die-off on the East Coast is the result of a virus.)