Early Birds Sported 4 Wings

Early Birds Sported 4 Wings - More than 100 million years ago, birds living in what is now China sported wings on their legs, a new study of fossils suggests.

Researchers found evidence of large leg feathers in 11 bird specimens from China's Shandong Tianyu Museum of Nature. The feathers suggest that early birds had four wings, which may have played a role in the evolution of flight, scientists report in a study published today (March 14) in the journal Science.

Chinese fossils reveal that ancient birds had feathers on their legs.

Most scientists believe that birds evolved from other feathered dinosaurs; this belief is supported by discoveries of fossils of feathery birdlike creatures. In 2000, scientists discovered a nonavian dinosaur with feathers on its arms and legs, called Microraptor, which could probably fly. In addition, specimens of Archaeopteryx, a transitional fossil between modern birds and feathered dinosaurs, show faint featherlike structures on their legs, but the signs are poorly preserved.

Now, leg feathers have been spotted in the 11 museum fossils that had been collected from the Lower Cretaceous Jehol formation in Liaoning, China, from a period about 150 million to 100 million years ago. The feathers are stiff and stick straight out from the birds' legs, and have a large enough surface area to be aerodynamic, the researchers say.

The fossils belong to at least four different groups, including the genera Sapeornis, Yanornis and Confuciusornis, as well as the Enantiornithes group. The findings suggest that leg feathers weren't just an evolutionary rarity.

The researchers also analyzed feathers of other birds and nonbird dinosaurs. Feathers covering the entire leg and feet first developed in dinosaurs, continued in early birds and later disappeared, the results imply. Birds gradually lost feathers on their feet and then their legs, and today, modern birds have wings on their arms only.

Whether these early birds used their leg feathers to fly, and how they may have done so, is up for debate. According to the study researchers, the flat surface formed by the stiff perpendicular feathers could have provided lift and maneuverability.

"These new fossils ?ll in many gaps in our view of the early evolution of birds," animal flight expert David Alexander of the University of Kansas, Lawrence, who was not involved in the study, told Science magazine. Alexander agrees that the feathers probably had some aerodynamic function, "although whether as stabilizers, steering vanes, or full-blown wings remains to be seen."

Other scientists aren't convinced. Paleontologist Kevin Padian of the University of California, Berkeley, told Science magazine that the authors don't provide evidence that the feathers contributed to any sort of flight. In fact, the feathers would create drag that would hinder flight, Padian said. The birds may have used their plumes for courtship instead, another scientist suggested.

More studies are needed to nail down the feathers' function. Examining more fossils from the thousands in the museum collection will help, the study's authors say. ( LiveScience.com )

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Bat-Eating Spiders Are Everywhere

Bat-Eating Spiders Are Everywhere, Study Finds - There's only one place in the world to escape bat-catching spiders: Antarctica. These arachnids ensnare and pounce on bats everywhere else in the world, researchers say.

Bats rank among the most successful groups of mammals, with the more than 1,200 species of bats comprising about one-fifth of all mammal species. Other than owls, hawks and snakes, bats have few natural enemies.

Still, invertebrates — creatures without backbones — have been known to dine on bats. For instance, giant centipedes in a cave in Venezuela were seen killing and eating bats, and the arachnids known as whip spiders were spotted feeding on dead bats in caves of the Caribbean. Cockroaches have been observed feeding on bat pups that have fallen to the floor of caves.

Spider-eat-bat world

Bat-eating spiders are common and apparently creep around every continent, except Antarctica, devouring various bat species. Here, a dead bat (Rhinolophus cornutus orii) caught in the web of a femaleNephila pilipes on Amami-O

A small bat (superfamily Rhinolophoidea) entangled in the web of aNephila pilipes spider at the top of the Cockatoo Hill near Cape Tribulation, Queensland, Australia. The spider pressed its mouth against the dead, wrapped bat, indicat

Accidental deaths of bats in spiderwebs were known as well, but were thought to happen very rarely. Still, spiders are known to occasionally dine on a variety of vertebrates — creatures with backbones. For instance, fishing spiders capture and devour fish and frogs; some species of wolf spiders, huntsman spiders, tarantulas and related spiders have been seen killing and eating frogs and lizards; and tarantulas and comb-footed spiders have apparently fed on snakes and mice. There are also numerous reports of spiders killing other flying vertebrates, snagging birds with large orb webs.

Recent studies of a web-building spider species (Argiope savignyi) and a tarantula species (Poecilotheria rufilata) both killing small bats led researchers to suggest that bat captures and kills due to spiders might be more frequent than previously thought. So they analyzed 100 years' worth of scientific reports, interviews of bat and spider researchers and the staff of bat hospitals, and scans of image and video sites. The search revealed 52 cases of bat-catching spiders worldwide. 

Giant webs

Approximately 90 percent of known bat-catching spiders live in the warmer areas of the globe, in the third of the Earth surrounding the equator. About 40 percent live in the neotropics — the whole of South America, and the tropical regions of North America — while nearly a third live in Asia and more than a sixth live in Australia and Papua New Guinea.

Eighty-eight percent of the reported cases of bat catches were due to web-building spiders, with giant tropical orb-weaving spiders with a leg-span of 4 to 6 inches (10 to 15 centimeters) seen catching bats in huge, strong orb-webs up to 5 feet (1.5 meters) wide.

In instances seen in Costa Rica and Panama, the spiders had built their webs near buildings inhabited by bat colonies. Bat-catching via spiderwebs was also witnessed particularly often in the parks and forests of the greater Hong Kong area. Future research may investigate whether the huge webs that sometimes block the entrances of tropical bat caves in east and southeast Asia and the neotropics may occasionally snag any members of the giant swarms of bats that emerge from the caves at night. 

The other 12 percent of cases of spider kills of bats were from spiders that hunt without webs. For instance, tarantulas were seen eating small bats in tropical rainforests in Peru and eastern Ecuador and on the forest floor in northeastern Brazil. A reddish parachute tarantula (Poecilotheria rufilata) was also seen predating on a small bat in Kerala, India, while a huntsman spider (Heteropoda venatoria) was observed capturing and killing a small bat in a shed near Kolkata, India. An attempt by a large fishing spider (Dolomedes triton) to kill a bat pup was also witnessed below a bridge in Indiana.

The victims

Most bat prey of spiders are small or juvenile insect-eating bats, and usually are among the most common bat species of their areas. Bats entangled in webs were usually 4 to 9.5 inches (10 to 24 cm) in wingspan, including some of the smallest species of bats in the world, and they sometimes died of exhaustion, starvation, dehydration or overheating — but there were many cases where spiders were seen actively attacking, killing and eating these victims.

Bats are likely capable of detecting spiderwebs via echolocation, their biological sonar. Even if bats do collide with spiderwebs, only the strongest traps are likely capable of withstanding the energy of such an impact without breaking. As such, bat captures are likely rare.

Still, as scarce as spider captures of bats likely are, they would prove well worth the effort. The catch of a 2-gram bat by the giant orb-weaving spider Nephila pilipes, a common killer of bats, would be a bonanza about 10 times the mass of the average daily catch of insect prey, researchers noted. ( LiveScience.com  )

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Parrots Can Reason Like 3-Year-Old Kids

Parrots Can Reason Like 3-Year-Old Kids - Parrots can draw conclusions about where to find a food reward not only from clues as to its location, but also from the absence of clues — an ability previously only seen in humans and other apes.

In a new study, researchers tested African Grey parrots on their reasoning abilities by shaking empty boxes and boxes filled with food so that the parrots could hear the snacks rattling around. To pick the box that would win them a treat, the parrots had to figure out that the sound indicated food and that a lack of sound from one box probably meant food in the other. It's a challenge that even human children can't reason through until about age 3.

African Grey Parrots show reasoning abilities similar to 3 year-old kids.

Experimenter Judith Schmidt works with an African Grey parrot.

"It suggests that Grey parrots have some understanding of causality and that they can use this to reason about the world," study scientist Christian Schloegl, a researcher at the University of Vienna, told LiveScience.

Reasoning parrots

African Grey parrots are known to be clever, as are many other birds. In earlier studies with Grey parrots, researchers have shown them two opaque boxes, one full of food and one empty. When the parrots are shown that one box has no food in it, they almost always pick the second box in search of a treat. 

This could be because the parrots infer that if one box is empty, the other is likely full, Schloegl said. But researchers couldn't rule out that they were simply avoiding the empty box for some unknown reason.

To find out, Schloegl, along with fellow University of Vienna researcher Judith Schmidt and colleagues, set up a more challenging task. In their new study, six African Grey parrots were presented with two opaque boxes, one containing walnuts and one empty. Instead of showing the parrots the empty box, however, the researchers shook the boxes so the parrots could hear the walnuts inside.

In some cases, the researchers shook either both of the boxes or neither box. In others, they shook just the empty box or just the full one. They found that the parrots could correctly determine that a noisy box was a full box. Even more impressively, when presented with a box that made no sound when shaken, the birds consistently picked the other box, seemingly reasoning that it must be full.

Evolution of intelligence

The results, detailed today (Aug. 7) in the journal Proceedings of the Royal Society B, prove that parrots can make judgments based on sounds as well as sight. But the birds still might have been avoiding the silent box rather than making inferences about the other box.

To rule out that possibility, Schmidt conducted several similar experiments, varying the types of motion and combinations of shaking and sound. In the final test, she wore tiny speakers snaked through her sleeves and attached to her wrists. When she picked up the boxes to shake them, the noise didn't come from the boxes but from the speakers.

In some cases, the speaker noise matched Schmidt's actions: She'd shake the box in her right hand and the sound would come from the hidden speaker on her right wrist. In other cases, the noise played from the opposite side of the box that she was shaking.

The parrots, she found, picked the correct, food-filled box at rates greater than random chance only when the shaking and the recorded noise matched up. In other words, the birds saw the connection between the motion and the noise, and then made the logical leap to connect both, but not one or the other, with food.

"The most important point is that higher intelligence is nothing that evolved only once," Schloegl said. Instead, he said, "comparable cognitive skills evolved several times in parallel in only distantly related species such as primates and birds." ( LiveScience.com )

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Whale Songs Found in Seismic Recordings

Whale Songs Found in Seismic Recordings - A rich, but untapped trove of whale calls hides in decades of recordings collected by geologists surveying the ocean floor.

The recordings come from seismic studies that shoot powerful air guns underwater to jiggle the Earth and learn more about its makeup. Sensors listen to acoustic waves in the water before, during and after the shots, capturing the reflections from the ground. But they can also pick up songs from any passing marine life that chats on the same frequency — fin whales and blue whales, in this case.

Blue whales do a graceful turn before lunging at their prey from below, a new study finds.

Whale calls recorded during a seismic survey in the Gulf of California. Top: This spectrogram of ocean sound was recorded by a hydrophone during an air gun seismic experiment in the Gulf of California in 2002. Color indicates the loudness of 

Extracting those squeals, squeaks and moans from the recordings could greatly improve scientist's understanding of the air gun's effects on whales. The noise could potentially confuse or even harm marine life, according to researchers at the Woods Hole Oceanographic Institution (WHOI) in Woods Hole, Mass. The calls may reveal how whale behavior changes in response to the sudden, sharp bursts in many different settings.

"We're really excited about the potential for it," said Laela Sayigh, a WHOI marine biologist. "There is a treasure trove of data."

Funding needed

The goal: Create a computer algorithm to extract the whale calls from data collected during a 2002 research cruise in Mexico's Gulf of California. The Gulf is a birthing ground for blue whales, and teems with marine life. Researchers will analyze whale behavior before, during and after the air gun blasts.

The cruise included onboard observers to track the effects of airguns on marine life, so scientists could potentially link calls to individual animals by matching the calls with those observations.

"We have a huge amount of data that can say, 'Did they change their behavior? Did they stop feeding? Did they stop talking? Did they talk louder?', and that's what we want to know," said WHOI seismologist Dan Lizarralde.

For now, the project is only an idea, because Sayigh and Lizarralde have no money for the research. Woods Hole turned the researchers down for an internal grant. This month they will apply for a grant from the Navy, which uses sonar and underwater explosions during training, and funds research exploring the effects of ocean noise on marine life.

Whale calls recorded during a seismic survey in the Gulf of California. Top: This spectrogram of ocean sound was recorded by a hydrophone during an air gun seismic experiment in the Gulf of California in 2002. Color indicates the loudness of the sounds, with yellow the loudest. Dark blue represents when the air guns were not being fired. The bright yellow signals ranging from about 17 to 30 Hertz are calls from fin whales, according to WHOI researchers.

Middle: A 5-hour span from the first panel shows more detail in the sounds. The brief blank periods between are short silences between intense whale call activity.

Bottom: A 5-minute span from the second panel show the presence of at least two fin whales, one much close to the hydrophone than the other.

Ocean noise and marine life

Parking hydrophones underwater to listen to whales is not new, but looking for the calls in seismic survey data is. As long as whales are calling, this precise method of monitoring them could track individuals and groups of whales through the water, showing researchers how the whales react to the blasts, Sayigh said.

Whale researchers have tracked the animals with underwater devices for decades, said Susan Parks, a bioacoustics expert at Pennsylvania State University who studies right whales with underwater recordings. "This is proven technology," she said. "I think it's an interesting idea, and it's really quite promising," she said. 

Dorian Houser, director of bioacoustical research for the National Marine Mammals Foundation, said Sayigh's and Lizarralde' project has potential. "We are really in the dark in a lot of the response of the animals to [ocean noise]," Houser told OurAmazingPlanet. "There's a big push to try and understand these exact questions: How does a whale's behavior change when they are exposed to these exact sounds, and what is the consequence?"

Sayigh thinks the project may also answer questions about the beaching of two Cuvier's beaked whales. Those whales came ashore while the 2002 research cruise that collected this data was in the Gulf, and the cruise was accused of playing a role in the deaths. "They know the exact amplitude of all their shots, and could extrapolate the likely location for the whales," Sayigh said.

If Sayigh and Lizarralde succeed in getting funding, there's a huge archive of seismic data waiting for future studies. Since 1999, all recordings from research cruises like Lizarralde's, funded by the National Science Foundation, go into an open-access archive called IRIS, the Incorporated Research Institutions for Seismology.

"We'll keep trying," Lizarralde said. "I really want to see what the behavior is associated with these air guns.

"I've convinced myself from observations that the whales are completely uninterested, that it's probably annoying but not damaging, but I'd like to know that better," he said. ( LiveScience.com )

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Extreme Earth Microbes Pave Way for Discovery of Alien Life

Extreme Earth Microbes Pave Way for Discovery of Alien Life - The region beneath Earth's surface may be crawling with diverse organisms, and now researchers reveal the lives of just one group of bizarre beasties: methane-spewing microbes that hide out in the cracks of hot undersea volcanoes.

Called high-temperature methanogens, these microbes rely on the hydrogen and carbon dioxide in their superheated deep-sea vents for growth, excreting waste products like methane.

The possibility of past or present life on other worlds such as Mars, where the rover Curiosity has just set out to investigate whether the environment was ever fit for microbes, will become clearer by figuring out the extreme limits (or minimum requirements) for some organisms on Earth.

The research submarine Alvin reaches with its mechanical arm to a high-temperature black smoker at the Endeavour Segment, Juan de Fuca Ridge, to study methanogenic microbes.

"Evidence has built over the past 20 years that there's an incredible amount of biomass in the Earth's subsurface, in the crust and marine sediments, perhaps as much as all the plants and animals on the surface," microbiologist James Holden at the University of Massachusetts said in a statement. "We're interested in the microbes in the deep rock, and the best place to study them is at hydrothermal vents at undersea volcanoes. Warm water flows bring the nutrient and energy sources they need."

One way to figure out what's hidden beneath Earth's crust in extreme environments is to figure out the energy requirements of an organism and then see if various spots meet these thresholds for life. "We're really interested in the equivalent of, 'What is the size of your paycheck and what's the cost of living?'" Holden told LiveScience. "How much energy is available for microorganisms: the paycheck. And what's the lower threshold – they need this much energy to live in this environment."

To do this, the researchers collected methanogens from hydrothermal vents and tried growing them (along with commercially bought microbes) on different levels of hydrogen. From these experiments, they found the bare minimum of hydrogen that these microbes needed to survive (they all needed about the same concentrations).

Next, Holden and colleagues sent the deep submersible vehicle Alvin to test out the findings at two spots: the Axial volcano and the Endeavor segment, both observatory sites along an undersea mountain range well off the coast of Washington state and Oregon and about 1 to 1.5 miles (1.6 to 2.4 kilometers) below the surface of the Pacific Ocean.

Alvin collected samples from the sites' black smokers, where mineral-rich, superheated water ? up to 662 degrees Fahrenheit (350 degrees Celsius) ? spews out of Earth's crust through cracks in the seafloor, and it also took samples from surrounding, lower-temperature waters.

The hydrogen limits found in the lab held up in the field. At the Axial volcano site, where the scientists found hydrogen levels above the lab-determined threshold, they also found evidence of methanogenic microbes; at Endeavour, hydrogen levels were below the threshold, with evidence of methane-producers largely absent. However, they found heat-loving methanogens could survive by feeding on hydrogen produced by other extreme organisms living near the vent.

In addition to painting a more comprehensive picture of Earth's biodiversity today, the findings may reveal what life was like on early Earth, "where we think [life] was independent of sun and oxygen," Holden said.

His research also can be used beyond Earth, he says; the astrobiology community uses this sort of data to rule in or out the possibility of past extraterrestrial life on, say, Mars or the Jupiter moon Europa.

"How much energy is available and what's the 'cost of living' for these organisms, and could Mars have had enough energy to support this kind of life?" Holden said during a telephone interview.

The research, detailed this week in the journal Proceedings of the National Academy of Sciences, was supported by the National Science Foundation, NASA Astrobiology Institute and the National Oceanographic and Atmospheric Administration. ( LiveScience.com )

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Beetles' Sticky Feet Lay Groundwork for Undersea Robots

Beetles' Sticky Feet Lay Groundwork for Undersea Robots - Tomorrow's robots could climb up submerged walls in the manner of an underwater Spider-Man by using a gripper design found in beetles.

A number of beetle species can walk straight up smooth, dry plant leaves due to sticky adhesive-covered hair-like structures known as setae at the tips of their legs. Researchers analyzing ladybugs and a leaf beetle (Gastrophysa viridula) unexpectedly discovered that those insects also could use these setae to walk underwater.

A ladybug walks underwater up a wall. Its sticky feet have inspired an artificial version that could help underwater robots.

To better understand how, scientists let specimens walk down sticks into trays of water. The researchers saw air bubbles trapped between the beetles' setae — bubbles that helped keep the adhesive-covered setae dry and sticky.

The investigators designed an artificial material that mimicked these beetle grippers — a silicone rubber pad covered with silicone rubber bristles about one-tenth of an inch high (2.4 millimeters), with tips about one-hundredth of an inch wide (0.2 mm). They used these pads to stick a plastic toy bulldozer onto the side of a wall underwater.

Even when these artificial grippers were not covered with glue, they were sticky underwater. The air bubbles themselves acted as an adhesive through capillary action, the same phenomenon by which liquids flow up paper towels.

This research could lead to "the application of adhesive devices for robots in the future," researcher Naoe Hosoda of Japan's National Institute for Material Science told InnovationNewsDaily.

This work also might lead to environmentally friendly adhesives for underwater use, Hosoda added.

Hosoda and her colleague Stanislav Gorb detailed their findings in the journal Proceedings of the Royal Society B: Biological Sciences. ( LiveScience.com )

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Bills seek end to farm animal abuse videos

Bills seek end to farm animal abuse videos — An undercover video that showed California cows struggling to stand as they were prodded to slaughter by forklifts led to the largest meat recall in U.S. history. In Vermont, a video of veal calves skinned alive and tossed like sacks of potatoes ended with the plant's closure and criminal convictions.

Now in a pushback led by the meat and poultry industries, state legislators across the country are introducing laws making it harder for animal welfare advocates to investigate cruelty and food safety cases.

 

Associated Press/Humane Society of the United States, file - FILE - In this April 22, 2010 image from video provided by the United States Humane Society, a Hallmark Meat Packing slaughter plant worker is shown attempting to force a "downed" cow onto its feet by ramming it with the blades of a forklift in Chino, Calif. State legislators across the country are introducing laws making it harder for animal welfare advocates to investigate cruelty and food safety cases. Bills pending in California, Nebraska and Tennessee require that anyone collecting evidence of abuse turn it over to law enforcement within 24 to 48 hours - which advocates say does not allow enough time to document illegal activity under federal humane handling and food safety laws. Critics say the bills are an effort to deny consumers the ability to know how their food is produced. (AP Photo/Humane Society of the United States, file)

Some bills make it illegal to take photographs at a farming operation. Others make it a crime for someone such as an animal welfare advocate to lie on an application to get a job at a plant.

Bills pending in California, Nebraska and Tennessee require that anyone collecting evidence of abuse turn it over to law enforcement within 24 to 48 hours — which advocates say does not allow enough time to document illegal activity under federal humane handling and food safety laws.

"We believe that folks in the agriculture community and folks from some of the humane organizations share the same concerns about animal cruelty," said Mike Zimmerman, chief of staff for Assembly Member Jim Patterson, R-Fresno, whose bill was unveiled this week. "If there's abuse taking place, there is no sense in letting it continue so you can make a video."

Patterson's bill, sponsored by the California Cattlemen's Association, would make failing to turn over video of abuse to law enforcement within 48 hours an infraction punishable by a fine.

Critics say the bills are an effort to deny consumers the ability to know how their food is produced.

"The meat industry's mantra is always that these are isolated cases, but the purpose of these bills is to prevent any pattern of abuse from being documented," said Paul Shapiro, vice president of farm animal protection for the Humane Society of the United States, which conducted the California and Vermont investigations.

In Indiana, Arkansas and Pennsylvania it would be a crime to make videos at agricultural operations.

The goal of the proposed California law, industry representatives say, is to halt any abuses quickly and get video evidence to government regulators within two days, not to impede undercover investigations by animal welfare groups.

"The people doing this aren't cops so I wouldn't think it's their job to build a case. The goal for all of us is to reduce instances of animal abuse," said David Daley, a Cattlemen vice president and professor of agricultural science at California State University-Chico.

Formal opposition to the California bill comes from the ASPCA, the Teamsters, the HSUS and dozens of others. They say these attempts by the agriculture industry to stop investigations are a part of a nationwide agenda set by the American Legislative Exchange Council, a conservative think tank backed by business interests.

ALEC has labeled those who interfere with animal operations "terrorists," though a spokesman said he wishes now that the organization had called its legislation the "Freedom to Farm Act" rather than the "Animal and Ecological Terrorism Act."

"At the end of the day it's about personal property rights or the individual right to privacy," said spokesman Bill Meierling. "You wouldn't want me coming into your home with a hidden camera."

Animal welfare advocates say all of the focus on secrecy is energy misspent.

"I wish the cattlemen actually wanted to stop cruelty, not the documenting of cruelty," said HSUS California director Jennifer Fearing. "One could think of a thousand ways for them to actually stop cruelty rather than waiting for people to make videos and turn them over."

Animal welfare advocates say law enforcement agencies do not have the time or inclination to work complex animal abuse and food safety cases, and that federal USDA inspectors in slaughter plants have turned a blind eye to abuse.

When a USDA inspector at the Vermont plant was heard in 2009 coaching a plant worker on how to avoid being shut down, U.S. Agriculture Secretary Tom Vilsack weighed in, calling the conduct "inexcusable."

In reaction to concerns, the USDA has been working to improve enforcement of its humane handling regulations over the past two years, including establishing an ombudsman position that accepts reports of violations. Last year 24 new positions in the Food Safety Inspection Service were dedicated to humane handling, said a high-ranking food safety official not authorized to speak publicly.

That hasn't slowed investigations or the bills designed to stop them. The Arkansas bill goes further than the others and would prohibit anyone other than law enforcement from investigating animal cases.

Last year Iowa, a major egg-producing state, passed a bill making it illegal to deny being a member of an animal welfare organization on a farm job application. Utah passed one that outlaws photography.

Most of the sensational videos of abuse in recent years are shot by undercover operatives who surreptitiously apply and are hired by the meat processors for jobs within the facilities. One recorded last year by Compassion over Killing at Central Valley Meats in Hanford, Calif. showed a worker standing on a downed dairy cow's nostrils to suffocate it and others repeatedly shot in the head, prompting several fast-food hamburger to cancel contracts, at least temporarily.

Animal welfare groups say investigations take weeks because the operatives nose around only when they aren't performing the duties for which they were hired.

An HSUS investigator was in the Hallmark plant in Southern California for six weeks between October and November 2007, when the nonprofit turned over to the local district attorney evidence that included fraud in the federal school lunch program because animals too sick to walk were being slaughtered. In January 2008, HSUS released the video to force the DA to act. Two employees were convicted of cruelty charges.

Late last year, nine workers at a Wyoming pork processing facility were charged with animal cruelty after an HSUS video showed them kicking and tossing piglets and failing to euthanize a sow gravely injured by a worker while giving birth.

In 2009, HSUS spent 21 days in the Vermont slaughterhouse where male calves born to dairy cows were killed for veal.

"Believe me our investigators would like to be out of there as soon as possible. They're stoic, they're courageous, but they are not enjoying their work at all," said Mary Beth Sweetland, director of investigations for HSUS. ( Associated Press )

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