Photo: KungFuStu

A single change in a pigment gene is responsible for white tigers’ famous snowy coats, LiveScience reports. Zookeepers have inbred captive white tigers for decades in order to preserve their unique coat, but until now scientists did not know the genetic basis of the felines’ striking white fur.

The researchers mapped 16 related tiger genomes, which included animals with both white and orange fur. They found that one gene, called SLC45A2, turned up in a slightly altered version in the white tigers. It acts to inhibit yellow and red coloring but doesn’t impact black. That same gene change also affects some fish, chickens, horses and even European humans. The mutation itself does not appear to be detrimental to the animals’ health, the BBC reports.

A number of the white tigers found in zoos have health issues, such as eyesight problems and some deformities.

However, Luo and colleagues say these deficiencies are a consequence of inbreeding by humans and that the white coats are in no way indicative of a more general weakness in the Bengal variant.

Though white tigers populate zoos around the world and are often one of their most crowd-pleasing attractions, the animals are rarer than those displays let on. In fact, researchers think white tigers are now extinct in the wild. LiveScience elaborates: 

Records of white tigers in India date back to the 1500s, Luo and colleagues say. They appear able to survive in the wild, as their primary prey, such as deer, are probably colorblind. The animals were widely hunted, and the last known free-ranging white tiger was shot in 1958. Habitat destruction probably contributed to the cats’ decline.

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The Fight to Save the Tiger 
Tiger Tracks 

A Scottish wildcat. Photo: Peter Trimming

Scottish wildcats, the U.K.’s only remaining species of wild feline, look a little bit like adorable grey tabbies, slightly on the large size, with a bushy striped tail. But the species lived in Scotland long before any domestic relatives—or humans—arrived. Nicknamed “the tiger of the highlands,” the felines were rumored for years to be man-killers. The Scottish Wildcats Association makes clear that these fierce felines are no cuddly kittens:

Although classically portrayed as a ferocious and terrifying beast to be feared and hated, wildcats simply enjoy their personal space, daily schedule and peace. A wildcat will only attack something it’s hunting, or something that it feel is hunting it. When threatened their classic strategy is to turn on an aggressor hissing, growling and spitting furiously; just like a domestic cat their hackles raise and the back arches but rather than turn side on to try and look big, they mock charge like a big cat; stamping forwards at you hissing and spitting. The idea is to give you just enough doubt to give them an opportunity to escape. If given no other choice and in fear of its life, perhaps cornered or defending kittens, the cat will attack with all its fury.

Yet only about 100 of the wildcats remain, and researchers point to the common house cat as the main culprit behind the species’ demise, the BBC reports. Wildcats and house cats, it turns out, are interbreeding, and scientists project the species could be obliterated by house cat genes within two years.   

Paul O’Donoghue, a researcher calling for the species’ conservation, compared the 63,000 domestic cat genes to those of the wildcats. He combed through 140 years worth of wildcat specimens kept in London and Edinburgh museums in order to find pristine genetic samples, then compared those two standards to samples attained from wildcats in the wild.

O’Donoghue concluded that extinction due to hybridization is almost guaranteed, perhaps within two years, for the wildcat unless conservationists undertake drastic action. For him, that means trapping the wildcats that still maintain pure genes, breeding them, and perhaps even placing them in the care of volunteers—so long, of course, as there are no frisky house cats about.

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Dawww. Photo: aaronz

Yellowstone National Park is a vast expanse of largely-untouched natural beauty, a tract of the west home to bears and wolves and geysers and mountains. But where humankind’s direct influence is deliberately kept to a minimum, that strategy of do-no-harm doesn’t always seem to work. For the past few decades, lake trout have been taking over the rivers and lakes in Yellowstone, pushing out the local Yellowstone Cutthroat trout. The Greater Yellowstone Coalition:

Yellowstone Lake and its tributaries once supported an estimated 3.5 million Yellowstone cutthroat trout. Since the illegal introduction of lake trout in the 1980s, the cutthroat population in Yellowstone Lake has plummeted. Catch rates for Yellowstone cutthroats have significantly dropped as more and more lake trout are caught every year. The precipitous drop in cutthroat numbers is a result of lake trout predating on cutthroat trout.

But more than just affecting cutthroat trout, the invasion of the lake trout is being felt throughout the ecosystem. According to new research lead by Yale’s Arthur Middleton, the replacement of cutthroat trout with lake trout is leaving Yellowstone’s local population of grizzly bears without enough fish to eat. Middleton and colleagues:

Historically, Yellowstone Lake harboured an abundant population of cutthroat trout, but lake trout prey heavily on cutthroat trout and have driven a decline of more than 90 per cent in their numbers. Although cutthroat trout migrate up shallow tributary streams to spawn, and are exploited by many terrestrial predators, lake trout spawn on the lake bottom and are inaccessible to those predators.

Without fish, the grizzlies need something, and in their place the bears have turned to eating baby elk.

In the late 1980s, grizzly and black bears killed an estimated 12 per cent of the elk calves in northern Yellowstone annually. By the mid-2000s, bears were estimated to kill 41 per cent of calves.

The researchers say that by turning to elk calves in place of the now-gone trout, the elk population growth rate has shrunk by 2 to as much as 11 percent. The research reminds that the food web is in fact a web, and that the illegal introduction of a few trout can mean a whole lot of dead elk.

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Photo: Beverly & Pack

Bottlenose dolphins working for the U.S. Navy discovered a rare 19th century torpedo off the coast of Coronado, Calif., while searching for underwater mines and other objects that evade technological detection. The brass torpedo is 11 feet long and weighs 132 pounds, and it could range 400 yards when launched. Called a Howell torpedo, the old military relic was a marvel in its day, the Los Angeles Times reports, and will likely find a home in a military museum.

While not as well known as the Gatling gun and the Sherman tank, the Howell torpedo was hailed as a breakthrough when the U.S. was in heavy competition for dominance on the high seas. It was the first torpedo that could truly follow a track without leaving a wake and then smash a target, according to Navy officials.

Only 50 were made between 1870 and 1889 by a Rhode Island company before a rival copied and surpassed the Howell’s capability.

Until recently only one Howell torpedo was known to exist, on display at the Naval Undersea Museum in Keyport, Wash. Now a second has been discovered, not far from the Hotel del Coronado.

The dolphins that uncovered the long-lost treasure use a biosonar system more sophisticated than any modern technology can provide. When dolphins find an object of interest, they resurface and tap the front of their handlers’ boat with their snouts. Last month, a dolphin named Ten indicated something was submerged in the area where the torpedo was later discovered, though at the time its human handlers dismissed the signal since they didn’t expect to find any objects there. Last week, another dolphin named Spetz alerted its handlers to the same spot, and this time the humans paid attention.

Navy divers and then explosive-ordnance technicians examined the object, which was in two pieces, and determined that the years had rendered it inert. On one piece was the stamp “USN No. 24.”

The torpedo pieces were lifted to the surface and taken to a Navy base for cleaning and to await shipment to the Naval History and Heritage Command, located at the Washington Navy Yard.

According the the LA Times, the divers had to consult both Google and military experts to reveal the identity of the ancient torpedo.

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Image: USFWS

For every endangered animal, there are probably at least two plans to save it. Many of these plans involve raising public awareness, conserving habitat, removing invasive species or breeding new members in captivity. But for the marbled murrelet, the plan is a little different: making their predators vomit.

Basically, scientists are going to paint the odorless, tasteless chemical called carbachol onto the eggs of the marbeled murrelet. This way, when an egg-eating Steller’s jay comes along and tries to chow down on the endangered birds’ vulnerable eggs, the jay will puke immediately. This sudden, extreme response is perfect for teaching jays to avoid murrelet eggs, researcher Keith Benson told Live Science: ”All of a sudden, their wings will droop, and they throw up. That’s exactly what you want — a rapid response — so within five minutes, they barf up whatever they ate.”

This sort of conditioning of the jays is called conditioned taste aversion (CTA). The Fish and Wildlife Service explains that”[j]ays that ingest carbacholtreated eggs are expected to associate the unpleasant experience with murrelet eggs such that they modify their behavior and avoid ingesting actual murrelet eggsthey encounter in the future.”

This is actually part of a two-pronged strategy to keep the Steller’s jay from taking over murrelet territory. The second prong involves keeping humans from feeding the jays. It turns out that there are more jays near campgrounds—full of tasty trash—than there are anywhere else in their range.

The marbled murrelet is a weird little bird. It spends some of its time in the redwood forest and some of its time in the Pacific Ocean. They’re like puffins—little duck like birds with webbed feet—which makes it odd to see them in the forest. But the birds breed in the forest, which is where the jay likes to snatch their eggs. Because of this egg snatching, along with deforestation and pollution, the murrelet population is down by over 90 percent compared to it nineteenth century population. The Steller’s jay, however, is doing quite well. The Cornell Ornithology lab describes them as “bold, inquisitive, intelligent, and noisy.” Now they can add “pukey” to that list.

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Photo: AmberBrooke.

If animals were to compete in a space-based reality survival show, lizards might emerge victorious. At least, that’s the indication of a Russian experiment concluded yesterday when a space capsule containing live mice, lizards, crayfish and fish was recovered around 750 miles south of Moscow, the Associated Press reports.

The capsule spent a month traveling 375 miles above the planet’s surface. That’s higher than the International Space Station’s orbit. The Russian scientists say that this experiment represents that longest period animals have ever spent alone in space and been recovered alive. In 2007, AP writes, the last research capsule to carry live animals into space spent only 12 days in orbit.

Not all of the research subjects made it, however.

Fewer than half of the 53 mice and other rodents who blasted off on April 19 from the Baikonur Cosmodrome survived the flight, Russian news agencies reported, quoting Vladimir Sychov, deputy director of the Institute of Medical and Biological Problems and the lead researcher.

Sychov said this was to be expected and the surviving mice were sufficient to complete the study, which was designed to show the effects of weightlessness and other factors of space flight on cell structure. All 15 of the lizards survived, he said.

The ordeal is not over for the surviving mice and lizards, however. They will be flown back to Moscow, where researchers will perform laboratory tests on them to better understand the atrophying effects of space.

The AP does not mention what happened to the crayfish and fish.

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Photo: stefanpinto

In the animal kingdom, larger males—think chimpanzees, lions, bulls—often try to acquire or defend more resources, like territory, food, and females, than their weaker underlings. Researchers decided to apply the competitive animal model to human political decision making about redistribution of wealth and income to see if there was any correlation.

The Atlantic describes the study:

Researchers at Aarhus University in Denmark and UC Santa Barbara collected from several hundred men and women in Argentina, the U.S., and Denmark. They categorized the subjects by socioeconomic class, their upper-body strength, or “fighting ability” (as measured by the “circumference of the flexed bicep of the dominant arm”), and their responses to a questionnaire gauging their support for economic redistribution.

They hypothesized that men with more upper body strength would be less open to wealth distribution, following the same tendency of stronger males of many animal species. After all, upper-body strength has counted as a major component of dominance throughout human evolutionary history. When economics, strength and gender were taking into account, that hypothesis turned out to be true. Popular Science reports:

Socioeconomic status also showed a correlation with economic views. As expected, rich men were generally opposed to redistribution, and poor men generally in favor of it. Men with stronger upper bodies tended to have stronger views–rich, strong men were very much opposed to redistribution, while less strong but still rich men were less opposed. On the side of those that support redistribution, the trend was reversed: poorer but strong men were strongly in favor of redistribution, while weaker poor men were not as committed.

Political party had nothing to do with the results, the researchers found, and no correlation turned up between women’s opinion on the subjet and their physical strength and/or wealth.

The authors conclude: “Because personal upper-body strength is irrelevant to payoffs from economic policies in modern mass democracies, the continuing role of strength suggests that modern political decision making is shaped by an evolved psychology designed for small-scale groups.”

For many men, apparently, animal antics still hold strong.

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A crazy ant queen. Photo: Joe MacGown, Mississippi Entomological Museum

Since fire ants first invaded the U.S. through cargo ships docking in Mobile, Alabama, the aggressive pest has taken a firm hold in the South and Southwest. More than $5 billion is spent each year on medical treatment and fire ant control, according to Food and Drug Administration, and the ants cost an additional $750 million in agricultural damage.

Now, however, there’s a new ant on the block. The crazy ant – also an invader from South America – is displacing fire ants in the U.S. by gobbling them up. But this unprescribed cure is likely worse than the disease it’s treating. The Los Angeles Times reports:

Like fire ants, these South American invaders seem to be fond of electrical equipment. But unlike their stinging red counterparts, the tawny crazy ants create mega-colonies, sometimes in homes, and push out local populations of ants and arthropods.

Thus  far, the crazy ants are not falling for the traditional poisons used to eliminate fire ant mounds. And when local mounds are destroyed manually, they are quickly regenerated.

Though the crazy ants don’t deliver the same burning bite as fire ants, they do stubbornly make their nests in bathroom plumbing or in walls. So far, researchers haven’t documented any native animals preying on the crazy ants, so their colonies are allowed to run amok, sometimes growing 100 times the size of other species of ants living in the area.

This isn’t the first time one ant invader has been displaced by another. The Argentine ant arrived back in 1891, followed by the black ant in 1918. But the fire ant put an end to those two invasive species when it arrived a couple decades later. Now, the fire ant’s own day of invasive reckoning may have arrived, but rather than feel relieved, researches are worried. Southern ecosystems have had time to adjust to fire ants. Crazy ants—well, who knows what they’ll do?

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Picture a mountain climber, trekking up Mount Everest. Is he kind of burly? Does he have a beard? He’s probably a man—a white man. That’s about accurate: 78 percent of Americans who took part in activities outdoors last year were white. Only 37 percent of African American kids between 6 and 12 did any sort of outdoor sport, from hiking to fishing.

Expedition Denali, a group of teachers and students dedicated to promoting hiking and outdoor activities among minority groups, just ran a successful Kickstarter to fund 12 teachers and students who will become the first African American team to reach the top of Denali—North America’s highest mountain. Here is their video:

Other organizations are trying to increase the diversity of their outdoor groups as well. Outside Magazine reports on the National Outdoor Leadership School:

In 1994, the Lander, Wyoming, nonprofit devised a diversity program that has since doled out more than $1.5 million in scholarships to help get minority youth into its courses, which teach wilderness and leadership skills through extended adventure trips. “We work hard to recruit young people of color, but we still struggle,” says Aparna Rajagopal-Durbin, who manages NOLS’s diversity program. “There are many barriers, including the lack of role models.” That’s where Expedition Denali comes in, and NOLS has budgeted nearly $250,000 for the group’s efforts.

Another website, Outdoor Afro, tries to encourage minorities to get outdoors as well. The group’s founder, Rue Mapp, explains why she started Outdoor Afro in this NPR interview. Her site describes the group’s purpose this way:

Outdoor Afro is a social community that reconnects African-Americans with natural spaces and one another through recreational activities such as camping, hiking, biking, birding, fishing, gardening, skiing — and more!

Outdoor Afro disrupts the  false perception that black people do not have a relationship with nature, and works to shift the visual representation of who can connect with the outdoors.

Together, these sites and expeditions hope to communicate with communities that don’t tend to participate in hiking, climbing, fishing and biking. And while they acknowledge that 12 people reaching the top of one mountain won’t solve all the problems, it can help raise awareness of the tiny numbers of minorities who hike in the first place.

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Photo: muffet

Pregnancy tests did not always come in an easy-to-use, sterile kit that provided almost immediate results. Less than a century ago, women had to rely upon frogs instead. In 1938, Dr. Edward R. Elkan wrote in the British Medical Journal:

The discovery of what is now known as the xenopus pregnancy test is based on experiments conducted by Hogben (1930, 1931), who observed that hypophysectomy produced ovarian retrogression, and the injection of anterior pituitary extracts ovulation, in the female South African clawed toad.

The African clawed frog, as its better known today, was imported around the world for its use in pregnancy tests. Doctors would ship urine samples to frog labs, where technicians would inject female frogs with a bit of the urine into their hind leg. The animals would be placed back into their tanks, and in the morning the technicians would check for tell-tale frog eggs dotting the water. If the female frog had ovulated, that meant the woman who provided the urine was pregnant and the pregnancy hormone, human chorionic gonadotropin, had kicked off ovulation in the frog. Researchers referred to this procedure as the Hogben test.

Among the 295 tests which I have done so far and in which 2,112 frogs were used I have not seen one clear positive that did not indicate a pregnancy. There were a few negative results which when repeated after a fortnight became positive, but I do not think that these can be regarded as failures.

Frogs were actually a great improvement on the previous means of testing whether or not a woman was pregnant.   Welcome History describes:

Prior to Xenopus, female mice and rabbits had been used, but these had to be slaughtered, dissected and carefully examined for ovarian changes. Because toads were reusable and could be conveniently kept in aquaria, Xenopus made pregnancy testing practical on a larger scale than before.

Thousands of the frogs were exported across the world from the 1930s to 1950s for use as pregnancy testers.

Immunological test kits finally replaced Xenopus in the 1960s and were rapidly taken up by private companies and feminist organisations offering diagnostic services directly to women. The first over-the-counter home test was sold in pharmacies in the early 1970s, but it resembled a small chemistry set and so was not user-friendly. It was not until 1988 that the first recognisably ‘modern’ one-step-stick hit the shelves.

But the frogs’ legacy lives on. African clawed frogs can be found living around many urban centers today, where they were likely released into the wild after hospitals no longer had use for them. Additionally, the imported frogs are common pets, and no doubt some of those pets wear out their welcome and get chucked into a local stream or pond.

In 2006, researchers realized that the frog may be carriers for the deadly amphibian chytrid fungus, which has caused the extinction and decline of around 200 amphibian species around the world. Now, research published in PLoS One shows for the first time that populations of African clawed frogs living in California carry the fungus. The frogs can carry the disease for long periods without being affected themselves, so researchers suspect that they may be the original vectors that introduced the fungus around the world—a sort of revenge for being used as egg-laying research subjects for all those years.

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Photo: dynna17

In elementary school, we learn that caterpillars turn into butterflies and moths through a process called metamorphosis. But what really goes on within the hardened chrysalis has continued to puzzle scientists. Now, computer tomography scans have allowed researchers to peep in on the caterpillar-to-butterfly action taking place inside the chrysalis, The Scientist reports.

Previously, researchers hoping to learn about metamorphosis had to dissect the chrysalis, which killed the developing insect inside. The key breakthrough about this new technique, they say, is that it allows them to study living tissue as it grows and changes.

Using series of dead individuals provides snapshots of presumably sequential development, but it can be unclear whether one insect’s third day in a chrysalis is really the same developmentally as another’s. CT scans can provide a more complete picture of how development proceeds.

In this new study, the team scanned nine painted lady chrysalises. Four of the insects died during the experiment while the other five hatched. In their results, the researchers focused on data derived from one of the insects in particular that provided the most detailed scans.

Here’s a video the researchers put together of their caterpillar’s gradual development into butterfly:

Rather than rewriting the story of butterfly development, the researchers told The Scientist, this experiment fills in missing details. For example, The Scientist describes:

The trachea did become visible surprisingly fast, within 12 hours after pupation, indicating that the structures either are more fully formed in caterpillars than previously thought or form very rapidly in pupae. While the trachea and the intestines showed up remarkably clearly, the “soft, gooey bits,” such as muscles and the central nervous system, were unfortunately invisible, Garwood said.

Lepidopterists, the scientists who study butterflies and moths, are not the only insect researchers who can benefit from CT scans. Many other arthropods—including beetles, flies, bees, wasps, ants and fleas—also go through metamorphosis.

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If you know of one of these female Mangarahara cichlids, let the London Zoological Society know. They need her help to save the species. Photo: Berlin Zoo

There are just three Mangarahara cichlids left in the world, so far as we know, and they’re all men. Two are at in the London Zoo, one is in Germany at the Berlin Zoo. The species was wiped out in the wild when the Mangarahara River in Madagascar dried up because of dams built to block the river, says the Associated Press.

The Berlin Zoo used to have a female, but she has unfortunately passed away, along with the best chance to revive the species in captivity. Now, the Zoological Society of London says in a release, they’re on a global quest to find a lady friend for their male cichlids. If you or anyone you know has one in a fish tank somewhere, they would really, really like to hear from you.

Launching the appeal, ZSL London Zoo’s Brian Zimmerman said: “The Mangarahara cichlid is shockingly and devastatingly facing extinction; its wild habitat no longer exists and as far as we can tell, only three males remain of this entire species.

“It might be too late for their wild counterparts, but if we can find a female, it’s not too late for the species. Here at ZSL London Zoo we have two healthy males, as well as the facilities and expertise to make a real difference.

If a female can’t be found, this wouldn’t be the first time we’ve had to sit idly by and watch a the last of a species wait out its final end. Just recently, Lonesome George, the last Pinta Island tortoise, passed away. And botanical gardens around the world feature the identical faces of the last E. woodii, each of them a clone of the same male plant.

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Australia’s Coorong lagoons are critically endangered, according to the new ecosystem assessment guidelines. Photo: Tom Paton

The IUCN Red List—the most comprehensive inventory of disappearing species around the world—warns that snow leopards are endangered and Mekong giant catfish are on the brink of extinction. But what about the habitats these species live in? In the journal PLoS One, an international team of 34 scientists propose that ecosystems, too, should be evaluated for red-list status.

In their paper, they write: 

The scientific challenges in building a unified risk assessment framework for ecosystems are likely greater than those faced during development of Red List criteria for species.

Many of the mechanisms and symptoms of species vulnerability are relevant to ecosystems, because species are integral parts of ecosystems. Yet ecosystems embody processes and higher-order components of biodiversity that are difficult or impossible to account for in species-by-species assessment.

Those obstacles include designing criteria both specific enough to capture the special features of any given ecosystem and general enough to apply all over the globe. To solve this problem, the team assessed 20 diverse ecosystems from around the world—seagrass meadows, coastal sandstone upland swamps, red gum forests and semi-evergreen vine thickets. Science World Report continues:

The scientists then used five criteria to determine whether these environments were critically endangered, endangered or vulnerable. These criteria included how fast the ecosystem was declining, the size of the area involved, the characteristics of the physical environment, biological processes and how they interact and how all of these factors come together.

From their initial analyses, the researchers gave each ecosystem a listing, such as “least concern,” “vulnerable” or “endangered.” Their results indicate that the Coorong lagoons in southern Australia, karst rising springs and coastal sandstone upland swamps are all critically endangered—on the verge of extinction, if business continues as usual.

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A modern day foraminiferan species. Photo: Scott Fay

Researchers have discovered a jackpot of ancient DNA buried under 5,000 meters of Atlantic water and the sea floor, ScienceNOW reports. The genetic material once belonged to single-celled sea animals that lived around 32,500 years ago. This is the first time ancient DNA has been recovered from such oceanic depths.

The researchers uncovered the samples from silt and clay deposits. They analyzed their samples for traces of DNA specific to two groups of single-celled organisms—foraminifera and radiolarians—using genetic sequences from modern, related organisms to identify the DNA they were after. Their analysis turned up 169 foraminifera and 21 radiolarian species, ScienceNOW reports, many of which are new to science.

Where there is some DNA, the researchers reason, there must be more.  If they’re correct, the deep sea could constitute a treasure trove of long-buried DNA waiting to be discovered. Such DNA, the team told ScienceNOW, expands scientists’ ability to study ancient biodiversity.

Significantly, the existence of some of these newly discovered species isn’t well documented in the fossil record. Since fossils only preserve animals with hard structures—bones, shells, exoskeletons—DNA preserved in the vast stretches of the ocean floor could provide a unique view of animals otherwise lost to the millennia.

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A female orb-weaver chowing down on a male. Photo: Kumon

The female black widow spider, as her name suggests, infamously devours her would-be suitors as they attempt to mate with her. These spiders are not the only sexual cannibals in the arthropod kingdom, either. Female praying mantises cannibalize their mates, sometimes decapitating and eating them while they are still mounted. Female orb-weaving spiders eat the smaller, more timid males and mate with the larger, more aggressive ones.

In an interesting case of role reversal, however, researchers just discovered that some male spiders also eat their mates. Micaria sociabilis, a small brown spider that lives in Europe, is more likely to eat his female mate than be eaten by her. The researchers see this phenomenon as evidence of male mate choice.

The study, which was only carried out with spiders in the lab rather than those observed in the wild, involved pairing male and female M. sociabilis of different sizes, ages and mating status to see what would happen. All of the spiders were fed ahead of time to discourage cannibalism due to hunger.

Reverse cannibalism, it turned out, depended heavily on the month in which the spiders met. Males tended to eat females most often in July. In the summer, males tended to be larger and also more cannibalistic, so the researchers speculate that male mate-eating aggression may be correlated with size. Cannibalistic males would eat their potential mates both before and after copulation.

Cannibalism occurred most frequently when large, young males from the summer batch met older females from the spring generation. So the behavior could also be based upon female age. Female body size did not turn out to be a significant factor in whether or not the female gets eaten, and neither did virginity.

Whatever the underlying reasons, in the case of M. sociabilis, males clearly call the shots on who they prefer to mate with and who will just serve as another convenient snack.

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