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Global temperature anomolies averaged over 2006 through 2010 (credit: NASA/Goddard Space Flight Center Scientific Visualization Studio, Data provided by Robert B. Schmunk (NASA/GSFC GISS))

The year 2010 may have had a La Niña and little solar activity—two factors that help to cool the planet—but it was record breaker for heat, tying 2005 as the hottest year on record. Record-setting or near-record-setting years are now common; after 2010 and 2005 comes 2009, virtually tied with 1998, 2002, 2003, 2006 and 2007.

To help visualize the heat, NASA recently released the movie above showing global temperature anomalies (the difference in temperature compared with the average for 1951 to 1980) from 1880 through 2010, thus driving home a single point: our planet is getting warmer.

CRF-overproducing mice at (A) four months old, when they were injected with astressin-B for five days, (B) three days after the injections, and (C) four weeks after the injections. (credit: UCLA/VA)

Before I go any further, I have to warn any balding individuals reading this hoping for a solution to their hair loss problems that I’m going to talk about a study in mice. Nothing—yet—has been tested in humans, so don’t get too excited.

Our story starts with a group of scientists studying chronic stress and its effects on gastrointestinal tract function in mice (their report appears in PLoS ONE). They were using mice genetically engineered to produce large amounts of the stress hormone corticotrophin-releasing factor, CRF, injecting them with a peptide, astressin-B, that blocks CRF, and then seeing what effect there was on the gastrointestinal tract. A single injection had no effect, so they repeated the injections over five days. At the end of their experiment, they did some measurements on the mice’s colons and put them back in their cages.

The CRF-overproducing mice don’t look like any old mice, though. A side effect of having all that extra stress hormone is that they develop allopecia and lose the hair on their backs as they age. So the scientists studying chronic stress with these mice weren’t expecting to find furry mice three months after their gastrointestinal study. In fact, they couldn’t tell the CRF-overproducing mice apart from normal mice. “When we analyzed the identification number of the mice that had grown hair we found that, indeed, the astressin-B peptide was responsible for the remarkable hair growth in the bald mice,” said study co-author Million Mulugeta of UCLA.

Repeated experiments confirmed this accidental finding; daily injections of astressin-B over five days prompted hair re-growth that lasted about four months, quite a long time for a creature that lives only two years. And the researchers also found that they could prevent hair loss in CRF-overproducing mice if they were treated with astressin-B while they were still young.

It’s a long way from a miracle cure for human balding, but this research “could open new venues to treat hair loss in humans,” Mulugeta said. When spray-on hair is an option, certainly there’s room for improvement.

Van Gogh's View of Arles with Irises (1888) (via wikimedia commons)

One of the features of Vincent Van Gogh‘s art that set him apart was his use of bright colors, made possible by the invention of industrial pigments such as chrome yellow. But in the century since, many of these colors, including the bright yellows of his famous sunflowers, have faded, turning brown after exposure to sunlight.

A group of chemists set out to discover what was happening with the paints, with the hope that they might one day be able to reverse the process; their study appears in Analytical Chemistry. They started by artificially aging paint samples taken from historic paint tubes by exposing them to light from a UV lamp for 500 hours. One sample, from a tube that had belonged to Flemish painter Fauvist Rikk Wouters, quickly turned brown. X-ray analysis revealed that the oxidation state of the chromium atoms had changed from Cr(VI) to Cr(III), a more stable form of the atom and one that appears green instead of yellow.

The chemists then applied their X-ray analysis to two Van Gogh paintings, View of Arles with Irises and Bank of the Seine, that reside at the Van Gogh Museum in Amsterdam. That analysis revealed that the change in oxidation state tended to occur when the chromium was mixed with compounds containing barium sulfate. Barium sulfate was a major component in lithopone, a white pigment commonly used during Van Gogh’s time, although there is no record of him using that pigment. The chemists speculate that Van Gogh mixed lithopone into his yellow paint, possibly as an extender to get more use out of it. He may have stretched his paint, but it appears he also lessened how long it would shine so brightly.

George Pollard Jr. was not a very lucky sea captain. In 1819, he became captain of the whaling ship Essex, out of Nantucket, Massachusetts, and headed for the Pacific Ocean. Just four days out, though, a storm struck and damaged the ship. Still, Pollard pressed on, rounding Cape Horn in January 1820 and then sailing north. Worse luck struck in November, when the ship was rammed twice by a large sperm whale. The Essex sank, and the crew piled into the small whaleboats with as much supplies as they could carry. It wasn’t enough, however—many men died and some had to resort to cannibalism to survive. The first mate wrote an account of the ordeal, and it inspired Herman Melville to write Moby Dick about Captain Ahab and his quest for the white whale.

When Pollard returned to Nantucket, he was given command of another whaling ship, the Two Brothers. And his back luck held. On the night of February 11, 1823, the ship struck a shallow reef off French Frigate Shoals, about 600 miles northwest of Hawaii. The crew members fared better that time, at least, and were rescued the next day by another Nantucket whaling ship. But Pollard’s career as a whaling captain was over. He made one trip on a merchant vessel and then spent the rest of his life as a night watchman, safe on dry ground in Nantucket.

A diver examines an anchor from the Two Brothers (credit: NOAA)

The Two Brothers remained hidden on the bottom of the sea until 2008 when marine scientists went on an expedition to the Northwestern Hawaiian Islands to study the marine life there. This area is part of the Papahānaumokuākea Marine National Monument, 140,000 square miles of protected ocean and one of the world’s largest protected areas.

Divers on the expedition first spotted a large anchor, the first clue that there might be some bigger find on the seafloor. Then they found other items, such as cast-iron pots, called trypots, of the type used to melt whale blubber, indicating that it wasn’t just any old wreck; marine archaeologists concluded that they had found a whaling ship.

Expeditions in 2009 and 2010 turned up items such as ceramics and glass that helped the scientists date the wreck, and first-hand accounts from sailors who had been on the Two Brothers approximately matched the location of the find. Now the scientists are ready to publicly conclude that the wreck was Captain Pollard’s ill-fated ship.

This is the first wrecked Nantucket whaling ship to ever be found, which is rather amazing considering how many hundreds of those ships were in existence during Nantucket’s whaling heyday in the 1700s and early 1800s, and how many must have sunk; whaling was never a safe occupation. “Shipwreck sites like this are important in helping tell the stories of the early days of sailing, including whaling and maritime activities both in the Pacific and around the world,” said Papahānaumokuākea Marine National Monument maritime archaeologist Kelly Gleason, who led the expedition.

Animal sex can get pretty weird. And we’re not comfortable with some of its variants. I’m sure I’m on someone’s watch list after researching this post; while searching for juicy examples, I kept coming across sites barred by the Smithsonian’s internet filter—such as the Wikipedia entry on “sexual cannibalism.” But scientists find it fascinating. A National Zoo great cats curator recently told my colleague Megan Gambino: “I think animal mating, while it’s very funny, is just a really interesting topic to talk about and one that people often shy away from because, oh, it’s taboo. But it’s pretty vital. It’s the very crux of existence.”

And so, in honor of today, here’s my top ten list of the worst—and weirdest—love stories from the world of biology:

10. Giant pandas: They are solitary creatures, and female pandas ovulate for only two or three days a year, so hooking up might be a bit of a problem in the wild. Even in captivity, panda mating isn’t always successful, leading zoo keepers to try everything from behavioral training to panda porn. The National Zoo’s current couple, Tian Tian and Mei Xiang, were unsuccessful in their mating attempts yet again this year; zoo curators then artificially inseminated Mei Xiang—which is how we got Tai Shan in 2005.

A female praying mantis will sometimes bite the head off her mate (image courtesy of flickr user paparutzi)

9. Pseudobiceros hancockanus: These orange-and-purple marine flatworms are hermaphroditic, meaning they can act as either a female or a male. How do they sort it out? Through penis fencing (see here for video). They battle each other with their penises and the winner pierces the other to deliver its sperm. The loser has to spend a lot of its energy and resources caring for the developing eggs.

8. Short-beaked echidnas: These spiky Tasmanian animals hibernate in winter, but that doesn’t deter some males from sex. They’ll happily mate with hibernating females; sometimes the females wake up, only to go back into hibernation, while others just sleep right through it. Scientists think that by re-entering hibernation, which would delay the development of a fetus, the female gets a chance to mate with a better quality male and abandon her first pregnancy.

7. Porcupines: The weird thing about porcupine sex has nothing to do with the quills. Male North American porcupines that want to mate with a female will first perform an elaborate dance, and then if she’s receptive, the female will let him douse her with urine. Ew!

6. Muscovy ducks: Males have a ballistic, corkscrew-shaped penis that they can use to force themselves onto unwilling females. Females, though, can fight back, at least against unwanted pregnancy, by refusing to relax her corkscrew-shaped genital tract. As a result, although a third of matings are forced, only three percent of offspring are born from those matings.

5. Redback spiders: When mating, the male redback spider performs a somersault that places his abdomen right above the female’s mouth, thus setting himself up to be eaten when copulation is done. It’s a noble sacrifice in the name of his genes—cannibalized males copulate longer and fertilize more eggs than males that survive mating, and females are more likely to reject other males after they’ve eaten their first mate.

4. Praying mantises: Like the redback spider, the female praying mantis often eats her mate. But she doesn’t always wait until they’re finished to start her meal. Sometimes the female will bite off the male’s head while they are copulating.

3. Bean weevils: The male bean weevil’s penis is covered with long, sharp spikes that can inflict serious scarring on a female. To make matters worse (for the female, that is), the longer the spines, the more successful the male is at depositing his sperm and fathering her young.

2. Banana slugs: Like the marine flatworms, banana slugs are hermaphrodites. When they copulate, each slug inserts its penis into the other. When they’re done, though, one slug may chew the penis off the other, and sometimes you end up with two penis-less slugs. Scientists call it apophallation.

1. Harpactea sadistica: This spider from Israel performs something called “traumatic insemination,” which is also characteristic of several insect species. The male injects sperm into the female by piercing her abdomen with his penis. This can leave an open wound prone to infection. Bedbugs, which also practice this method of copulation, at least provide the female with a spermalege that helps to repair the damage.