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Giant prehistoric turtle from Colombia chomped everything in sight–including crocodiles!

John Barrat — Thu, 17 May 2012 17:39:39 +0000

Picture a turtle the size of a Smart car, with a shell large enough to double as a kiddie pool. Paleontologists from North Carolina State University, the Smithsonian Tropical Research Institute and the Florida Museum of Natural History have just described such a specimen from the fossilized remains of this 60-million-year-old South American giant that lived in what is now Colombia.

Image right: Artist’s conception of Carbonemys eating a small crocodylomorph (Artwork by Liz Bradford)

The turtle in question is Carbonemys cofrinii, which means “coal turtle,” and is part of a group of side-necked turtles known as pelomedusoides. The fossil was named Carbonemys because it was discovered in 2005 in a coal mine that was part of northern Colombia’s Cerrejon formation. The specimen’s skull measures 24 centimeters, roughly the size of a regulation NFL football. The shell which was recovered nearby – and is believed to belong to the same species – measures 172 centimeters, or about 5 feet 7 inches, long. That’s the same height as Edwin Cadena, the NC State doctoral student who discovered the fossil.

Cadena; Dan Ksepka, N.C. State paleontologist and research associate at the North Carolina Museum of Natural Sciences; paleontologist Carlos Jaramillo of the Smithsonian Tropical Research Institute in Panama, and paleontologist Jonathan Bloch of the Florida Museum of Natural History are co-authors of the scientific description of the turtle which appears in the Journal of Systematic Paleontology.

Image left: Edwin Cadena, the scientist who discovered the fossil of Carbonemys, poses next to its reconstructed fossil shell. (Photo courtesy Dan Ksepka, NC State University)

“We had recovered smaller turtle specimens from the site. But after spending about four days working on uncovering the shell, I realized that this particular turtle was the biggest anyone had found in this area for this time period – and it gave us the first evidence of giantism in freshwater turtles,” Cadena says.

Smaller relatives of Carbonemys existed alongside dinosaurs. But the giant version appeared five million years after the dinosaurs vanished, during a period when giant varieties of many different reptiles – including Titanoboa cerrejonensis, the largest snake ever discovered – lived in this part of South America. Researchers believe that a combination of changes in the ecosystem, including fewer predators, a larger habitat area, plentiful food supply and climate changes, worked together to allow these giant species to survive. Carbonemys’ habitat would have resembled a much warmer modern-day Orinoco or Amazon River delta.

In addition to the turtle’s huge size, the fossil also shows that this particular turtle had massive, powerful jaws that would have enabled the omnivore to eat anything nearby – from mollusks to smaller turtles or even crocodiles.

Thus far, only one specimen of this size has been recovered. Palentologist Ksepka believes that this is because a turtle of this size would need a large territory in order to obtain enough food to survive. “It’s like having one big snapping turtle living in the middle of a lake,” he says. “That turtle survives because it has eaten all of the major competitors for resources. We found many bite-marked shells at this site that show crocodilians preyed on side-necked turtles. None would have bothered an adult Carbonemys, though – in fact smaller crocs would have been easy prey for this behemoth.”–Source: NC State University

Heliconius butterfly genome explains wing pattern diversity

John Barrat — Thu, 17 May 2012 01:25:58 +0000

Pooling funds and putting their heads together, more than 70 scientists from 9 institutions including the Smithsonian Tropical Research Institute, sequenced the entire genome of the butterfly genus Heliconius, a brightly colored favorite of collectors and scientists since the Victorian era. Their results are published in the prestigious journal, Nature.

Image right: Based on the new sequence, scientists found that different species copy each other’s wing patterns by exchanging genes, a process thought to be very rare, especially in animals. (Photo by Mathieu Joron)

The genome of the Postman butterfly, Panama’s Heliconius melpomene, helps scientists understand how the stunning diversity of wing color patterns in tropical butterflies evolved. Heliconius species are highly distasteful. Their vivid wing patterns warn predators not to eat them. How have different butterfly species evolved similar wing patterns?

Based on the new sequence, scientists found that different species copy each other’s wing patterns by exchanging genes, a process thought to be very rare, especially in animals. Although many different species interbreed in the wild, their hybrid offspring often cannot reproduce successfully. But sometimes hybrids gain useful genes that help them adapt to changing conditions. Heliconius hybrids gain wing patterns that help them survive.

Kanchon Dasmahapatra, the a lead author of the study and a former Smithsonian fellow who worked with Jim Mallet at University College London notes: “What we discovered is that one butterfly species can gain its protective colour pattern genes ready-made from a different species by hybridizing with it–a much faster process than having to evolve one’s colour patterns from scratch.”

Some of the other genes in the sequence also surprised researchers. These butterflies, typically regarded as primarily visual insects, apparently have a rich array of genes for smelling and sensing chemicals in their environment, raising new questions about the links between perception and the origins of new species. Indeed, analysis carried out at the University of California by co-author Adriana Briscoe showed that butterflies have an even greater array of genes involved in chemical communication than moths, which depend on chemical signals for finding mates and host plants.

The study heralds a new era in genome biology and an important step in the Smithsonian’s goal to understand and sustain a biodiverse planet. Low-cost genetic sequencing opens doors to small research groups and individuals to sequence entire genomes, a technique formerly accessible only to labs with major government funding.

“Assembling a genome from scratch is still hard work: think Humpy-Dumpty,” said Owen McMillan, geneticist and Academic Dean at the Smithsonian Tropical Research Institute, “but it is getting easy, inexpensive, and is transforming how we do science. At the core, having a reference genome opens up new research possibilities and reveals previously unimagined connections.

3D imaging adds remarkable new understanding of North America’s mysterious Clovis people

John Barrat — Thu, 10 May 2012 13:53:57 +0000

New high-tech 3D computer analysis of 50 spear points made more than 10,000 years ago by North America’s mysterious Clovis people has revealed the stone points display an astounding symmetry despite having been found in caches as far apart as Maryland, Arizona and Colorado. The only explanation for such symmetry across these vast distances, explains Smithsonian anthropologist Dennis Stanford, is that the method of creating the points was handed down from person to person.

“We were shocked. Basically what we are looking at is a technology that was learned from one person to another, from father to son or from uncle to nephew,” explains Stanford, co-author of a recent paper on the discovery in the Journal of Archaeological Science.

Image right: Clovis stone points from the Drake Cache of Colorado. Click to enlarge. (Photo by Chip Clark, Smithsonian)

The researchers believe encounters between Clovis knappers, or stone point makers, from different groups at stone quarry sites or in settlements certainly “facilitated the sharing of technological information by allowing knappers to observe tools and techniques used by other artisans,” explains co-author Sabrina Sholts of the Human Evolution Research Center at the University of California in Berkeley. “The tools selected by the knappers, as well as how they were handled and applied, certainly were part of the Clovis technology,” that was shared between families and tribes.

This video was created by Sabrina Sholts of the Human Evolution Research Center at the University of California in Berkeley using 3D digital scans of a Clovis stone projectile point from the collections of the Department of Anthropology, National Museum of Natural History, Smithsonian Institution.

In fact, the researchers say, through a strong communication network Clovis spear point technology spread across North America in as little as 200 years. Radiocarbon dating of the stone points backs this theory. Many Clovis points “have been recovered from kill sites, in association with the remains of animals such as mammoths and bison,” Sholts says. This “suggests that they were effective for hunting large prey.”

The scientists used high-tech 3D scanning to create detailed images of the Clovis points from the collection of the Smithsonian’s National Museum of Natural History. The researchers focused particularly on the contours of the scars on the front and back of each bi-face spear point where individual stone flakes were carefully and systematically removed centuries ago by striking with an implement made of antler, bone, ivory or even perhaps hardwood. Each 3D scan records millions of minute measurements, revealing “subtle differences in the various steps of reduction [flaking off tiny pieces of stone] and nuances that you can’t see with your eyes,” Stanford explains.

Right: Images of 3D models and overlaid front and back flake scar contours from projectile points from the Colby Cache, Wyoming (left), Drake Cache, Colorado (center left), and two modern replicas (center right and right). The Colby and Drake points have markedly different bases, but this difference is much less prominent in the flake scar contours. For the two modern replicas, their flake scar contours are generally more uneven, and also display larger differences between the overlaid contours.

“One nice thing about the study is its relative objectivity,” Sholts points out. With the 3D imaging, “it is really very automated. What we are doing is essentially data analysis, capturing the contours and curvature of the surface of each biface in a standard way. The results were surprising to me.”

This 3D study has laid to rest the theory that Clovis technology spread region by region from knappers who copied lost or discarded stone points they had found, Stanford says. In fact, the paper reveals, part of the research included projectile points made by an expert modern-day knapper who closely studied and copied Clovis points in the Smithsonian collection. Computer analysis revealed these modern creations do not share the same symmetry as do the authentic Clovis points—further proof that the real Clovis points were a learned technology.

“We are now working on a new study with Clovis points from California that we are putting into that same computer matrix,” Stanford says.–John Barrat

Article link: “Flake scar patterns of Clovis points analyzed with a new digital morphometrics approach: evidence for direct transmission of technological knowledge across early North America,” authored by Sabrina Sholts, Dennis Stanford, Louise Flores and Sebastian Wärmländer, will appear in a forthcoming issue of the Journal of Archaeological Science.

One supernova type, two different sources

John Barrat — Mon, 07 May 2012 18:31:42 +0000

The exploding stars known as Type Ia supernovae serve an important role in measuring the universe, and were used to discover the existence of dark energy. They’re bright enough to see across large distances, and similar enough to act as a “standard candle” – an object of known luminosity. The 2011 Nobel Prize in Physics was awarded for the discovery of the accelerating universe using Type Ia supernovae. However, an embarrassing fact is that astronomers still don’t know what star systems make Type Ia supernovae.

Two very different models explain the possible origin of Type Ia supernovae, and different studies support each model. New evidence shows that both models are correct – some of these supernovae are created one way and some the other.

Image above: The Tycho supernova remnant is the result of a Type Ia supernova explosion. The explosion was observed by Danish astronomer Tycho Brahe in 1572. More than 400 years later, the ejecta from that explosion has expanded to fill a bubble 55 light-years across. In this image, low-energy X-rays (red) show expanding debris from the supernova explosion and high energy X-rays (blue) show the blast wave – a shell of extremely energetic electrons. (Credit: X-ray: NASA/CXC/Rutgers/K.Eriksen et al.; Optical: DSS)

“Previous studies have produced conflicting results. The conflict disappears if both types of explosion are happening,” explained Smithsonian astronomer and Clay Fellow Ryan Foley (Harvard-Smithsonian Center for Astrophysics).

Type Ia supernovae are known to originate from white dwarfs – the dense cores of dead stars. White dwarfs are also called degenerate stars because they’re supported by quantum degeneracy pressure.

In the single-degenerate model for a supernova, a white dwarf gathers material from a companion star until it reaches a tipping point where a runaway nuclear reaction begins and the star explodes. In the double-degenerate model, two white dwarfs merge and explode. Single-degenerate systems should have gas from the companion star around the supernova, while the double-degenerate systems will lack that gas.

“Just like mineral water can be with or without gas, so can supernovae,” said Robert Kirshner, Clowes Professor of Astronomy at Harvard University and a co-author on the study.

Foley and his colleagues studied 23 Type Ia supernovae to look for signatures of gas around the supernovae, which should be present only in single-degenerate systems. They found that the more powerful explosions tended to come from “gassy” systems, or systems with outflows of gas. However, only a fraction of supernovae show evidence for outflows. The remainder seem to come from double-degenerate systems.

“There are definitely two kinds of environments – with and without outflows of gas. Both are found around Type Ia supernovae,” Foley said.

This finding has important implications for measurements of dark energy and the expanding universe. If two different mechanisms are at work in Type Ia supernovae, then the two types must be considered separately when calculating cosmic distances and expansion rates.

“It’s like measuring the universe with a mix of yardsticks and meter sticks – you’ll get about the same answer, but not quite. To get an accurate answer, you need to separate the yardsticks from the meter sticks,” Foley explained.

This study raises an interesting question – if two different mechanisms create Type Ia supernovae, why are they homogeneous enough to serve as standard candles?

“How can supernovae coming from different systems look so similar? I don’t have the answer for that,” said Foley.

The paper describing this research will appear in the Astrophysical Journal and is available online.

Heavyweight trees are forest champs at sequestering carbon

John Barrat — Thu, 03 May 2012 16:36:41 +0000

Big trees three or more feet in diameter accounted for nearly half the biomass measured at a Yosemite National Park site, yet represented only one percent of the trees growing there.

This means just a few towering white fir, sugar pine and incense cedars per acre at the Yosemite site are disproportionately responsible for photosynthesis, converting carbon dioxide into plant tissue and sequestering that carbon in the forest, sometimes for centuries, according to James Lutz, a University of Washington research scientist in environmental and forest sciences. Lutz is lead author of a paper on the largest quantitative study yet of the importance of big trees in temperate forests being published online May 2 on PLoS ONE. The research was funded by the Smithsonian Center for Tropical Forest Science.

Image right: A handful of large-diameter trees per acre, such as these incense cedars, together with remains of big trees like the three-foot-wide white fir snag and downed debris account for half the forest biomass at a Yosemite National park study site. (Image by James Lutz)

“In a forest comprised of younger trees that are generally the same age, if you lose one percent of the trees, you lose one percent of the biomass,” he says. “In a forest with large trees like the one we studied, if you lose one percent of the trees, you could lose half the biomass.”

In 2009, scientists including Lutz reported that the density of large-diameter trees declined nearly 25 percent between the 1930s and 1990s in Yosemite National Park, even though the area was never logged. Scientists have found notable numbers of large trees dying in similar areas across the West.

The new 63-acre study site is one of the largest, fully-mapped plots in the world and the largest old-growth plot in North America. The tally of what’s there, including the counting and tagging of 34,500 live trees, was done by citizen scientists. The site is part of the network of the Smithsonian Center for Tropical Forest Science, a global network of 42 tropical and temperate forest plots including the one in Yosemite.

Image left: Washington State University’s Mark Swanson pulls a tape tight around a 4-foot-wide sugar pine, one of the 34,500 live trees counted and tagged for long-term study in a Yosemite National Park study plot. (Washington State University)

One implication of the research is that land managers may want to pay more attention to existing big trees, the co-authors said. In some younger forests that lack big trees, citizens and land managers might want to consider fostering the growth of a few big-trunked trees, Lutz added.–Source: University of Washington.

Scientists catch black hole in a feeding frenzy

John Barrat — Wed, 02 May 2012 18:44:18 +0000

When it comes to scary things in the universe, it’s hard to get much scarier than supermassive black holes. These gigantic, invisible menaces lurk in the centers of galaxies, hungrily vacuuming up everything within reach – or so we think. But the truth is more benign. Supermassive black holes snack infrequently, making the recent discovery of a black hole in the act of feeding all the more exciting to astronomers.

“Black holes, like sharks, suffer from a popular misconception that they are perpetual killing machines,” said Ryan Chornock of the Harvard-Smithsonian Center for Astrophysics. “Actually, they’re quiet for most of their lives. Occasionally a star wanders too close, and that’s when a feeding frenzy begins.”

Image right: These images, taken with NASA’s Galaxy Evolution Explorer and the Pan-STARRS1 telescope in Hawaii, show a galaxy that brightened suddenly, caused by a flare from its nucleus. The top left image, taken in 2009, shows the galaxy before the flare, when it wasn’t visible in ultraviolet light. In the top right image, taken on June 23, 2010, the galaxy had become 350 times brighter in ultraviolet light. The bottom left image, shows the galaxy (the bright dot in the center) in 2009 before the flare’s appearance. The bottom right image, taken from June to August 2010, shows the flare from the galaxy nucleus. (Credit: NASA, S. Gezari (JHU), A. Rest (STScI), and R. Chornock (Harvard-Smithsonian CfA)

Chornock and his colleagues, led by Suvi Gezari of Johns Hopkins University, reported their discovery of a feeding supermassive black hole in the May 3 issue of the journal Nature.

If a star passes too close to a black hole, tidal forces can rip it apart.

Its constituent gases then swirl in toward the black hole. Friction heats the gases and causes them to glow. By searching for newly glowing supermassive black holes, astronomers can spot them in the midst of a feast.

The team discovered just such a glow on May 31, 2010 using the Pan-STARRS1 telescope on Mount Haleakala in Hawaii. The flare brightened to a peak on July 12th before fading away over the course of a year.

Image left: This computer-simulated image shows gas from a tidally shredded star falling into a black hole. Some of the gas also is being ejected at high speeds into space. Credit: NASA, S. Gezari (JHU), and J. Guillochon (UC Santa Cruz)

“We observed the demise of a star and its digestion by the black hole in real time,” said Harvard co-author Edo Berger.

The glow came from a previously dormant supermassive black hole at the center of a galaxy 2.7 billion light-years away. The black hole contains as much mass as 3 million suns, making it about the same size as the Milky Way’s central black hole.

Follow-up observations with the MMT Observatory in Arizona showed that the black hole was consuming large amounts of helium. Therefore, the shredded star likely was the core of a red giant star. The lack of hydrogen showed that the star lost its outer atmosphere on a previous pass by the black hole.

“This star barely survived one encounter with the black hole, only to meet its unfortunate end in round two,” said Chornock.

The discovery demonstrates the sleuthing power of the Panoramic Survey Telescope and Rapid Response System (Pan-STARRS), which was designed to locate all kinds of transient phenomena in the night sky.

Astronomers witness black hole outburst in Spiral Galaxy M83

John Barrat — Mon, 30 Apr 2012 18:04:05 +0000

An extraordinary outburst produced by a black hole in a nearby galaxy has provided direct evidence for a population of old, volatile stellar black holes. The discovery, made by astronomers using NASA’s Chandra X-ray Observatory, provides new insight into the nature of a mysterious class of black holes that can produce as much energy in X-rays as a million suns radiate at all wavelengths.

Researchers used Chandra to discover a new ultraluminous X-ray source, or ULX. These objects give off more X-rays than most binary systems, in which a companion star orbits the remains of a collapsed star. These collapsed stars form either a dense core called a neutron star or a black hole. The extra X-ray emission suggests ULXs contain black holes that might be much more massive than the ones found elsewhere in our galaxy.

Image right: On the left is an optical image of M83 from the Very Large Telescope in Chile. On the right is a composite image showing X-ray data from Chandra in pink and optical data from the Hubble Space Telescope in blue and yellow. The ULX is located near the bottom of the composite image. (Left image – Optical: ESO/VLT; Close-up – X-ray: NASA/CXC/Curtin University/R. Soria et al., Optical: NASA/STScI/Middlebury College/F. Winkler et al.)

The companion stars to ULXs, when identified, are usually young, massive stars, implying their black holes are also young. The latest research, however, provides direct evidence that ULXs can contain much older black holes and some sources may have been misidentified as young ones.

The intriguing new ULX is located in M83, a spiral galaxy about 15 million light years from Earth, discovered in 2010 with Chandra. Astronomers compared this data with Chandra images from 2000 and 2001, which showed the source had increased in X-ray brightness by at least 3,000 times and has since become the brightest X-ray source in M83.

“The flaring up of this ULX took us by surprise and was a sure sign we had discovered something new about the way black holes grow,” said Roberto Soria of Curtin University in Australia, who led the new study. The dramatic jump in X-ray brightness, according to the researchers, likely occurred because of a sudden increase in the amount of material falling into the black hole.

In 2011, Soria and his colleagues used optical images from the Gemini Observatory and NASA’s Hubble Space Telescope to discover a bright blue source at the position of the X-ray source. The object had not been previously observed in a Magellan Telescope image taken in April 2009 or a Hubble image obtained in August 2009. The lack of a blue source in the earlier images indicates the black hole’s companion star is fainter, redder and has a much lower mass than most of the companions that previously have been directly linked to ULXs. The bright, blue optical emission seen in 2011 must have been caused by a dramatic accumulation of more material from the companion star.

The companion to the black hole in M83 is likely a red giant star at least 500 million years old, with a mass less than four times the sun’s.

Another ULX containing a volatile, old black hole recently was discovered in the Andromeda galaxy by Amanpreet Kaur, from Clemson University, and colleagues and published in the February 2012 issue of Astronomy and Astrophysics. Matthew Middleton and colleagues from the University of Durham reported more information in the March 2012 issue of the Monthly Notices of the Royal Astronomical Society. They used data from Chandra, XMM-Newton and HST to show the ULX is highly variable and its companion is an old, red star.

A paper describing these results will appear in the May 10th issue of The Astrophysical Journal.

NASA’s Marshall Space Flight Center in Huntsville, Ala., manages the Chandra program for NASA’s Science Mission Directorate in Washington. The Smithsonian Astrophysical Observatory controls Chandra’s science and flight operations from Cambridge, Mass.

Smithsonian astronomers and colleagues to photograph black hole at our galaxy’s heart

John Barrat — Wed, 11 Apr 2012 13:06:33 +0000

How do you see the invisible? That’s the puzzle faced by astronomers wanting to study black holes. A black hole gets its name for good reason – its strong gravity is so extreme that nothing can escape it, not even light. But with the right technology and some clever techniques, the invisible will be revealed before the decade is out.

Smithsonian astronomers have joined their colleagues from other observatories in a daring new venture: to photograph the giant black hole at the heart of our Milky Way galaxy. Their bold effort will require nothing less than an Earth-sized telescope, which has been named the Event Horizon Telescope or EHT. (The event horizon is a black hole’s boundary or outer edge – the point of no return.)

“For the first time, we intend to take a picture of a black hole, or more precisely its shadow,” says Jonathan Weintroub of the Smithsonian Astrophysical Observatory (SAO). SAO is a key part of the international collaboration working to create the EHT.

Image above: This simulation shows what the Milky Way’s central black hole may look like to the Event Horizon Telescope. Powerful gravitational forces bend light around the black hole, leaving a silhouette against a glowing background. Credit: A. Loeb & A. Broderick (CfA)

They’ve targeted the Milky Way’s central black hole because it covers the largest apparent area of the sky. Physically, it spans about 7 million miles (12 million km). That may sound large, but it’s located 26,000 light-years from Earth, or 150,000 trillion miles. It appears the size of a poppy seed in Los Angeles as seen from Boston. As a result, observers will need extremely high resolution to tease out any details.

Another challenge is that the galactic center is cloaked in gas and dust and crowded with stars. Almost no visible light from this region makes it to Earth. Radio waves can penetrate the gloom, so the Event Horizon Telescope will focus on the radio spectrum. These radio waves are naturally occurring, coming from both hot gas and free-flying electrons surrounding the black hole.

The black hole feeds on gas and dust swirling around it like water draining from a bathtub. As that material spirals inward, friction heats it and causes it to shine. The black hole is silhouetted against that glowing background.

The black hole’s gravity also bends light passing nearby – an effect known as gravitational lensing. As a result, theorists calculate that the Event Horizon Telescope will show a bright, circular outline with the black hole’s shadow at the center.

To get this iconic photo, a worldwide network of radio telescopes must link together in a technique called “interferometry.” In essence, interferometry provides the same resolution (although not the same light-gathering power) as a single telescope thousands of miles across. The Smithsonian’s Submillimeter Array, located atop Mauna Kea in Hawaii, will join this network.

“The Submillimeter Array will be a vitally important component of the Event Horizon Telescope,” Weintroub says. “Its location, collecting area and sensitivity all will contribute to the success of this effort.”

He emphasizes that the project will be a gradual process as more facilities link together. Initially, researchers will measure only the most basic information about the black hole – its size. As they gather more data, glowing “hot spots” may emerge from the black hole’s swirling accretion disk. Eventually, the full picture of the black hole’s environment will be unveiled.

The Event Horizon Telescope ultimately may link observatories in Hawaii, Arizona, California, Mexico, Chile, Europe, and Antarctica. Its best performance will come when the Atacama Large Millimeter/Submillimeter Array (ALMA), now under construction in Chile, joins the network.

“We are poised to catch a wave as ALMA comes online,” Weintroub says. “Once its capabilities are added to this project, we expect to get some amazing results. By the end of the decade, we should have the first-ever close-up photo of a black hole.”–By Christine Pulliam

5 rabbit realities

John Barrat — Fri, 06 Apr 2012 12:06:24 +0000

In celebration of the annual spring appearance of the Easter bunny on Sunday, April 8, Smithsonian Science offers these facts from Rabbits: The Animal Answer Guide, a new book by John Seidensticker, conservation scientist at the Smithsonian’s National Zoo, and Susan Lumpkin, freelance writer.

1

Rabbits are not rodents, but lagomorphs (lag-uh-mawrf), a scientific term which means “hare-shaped.” Hares and pikas also are lagomorphs.

Image: A domestic rabbit, breed: Silver Fox (Photo by Mehgan Murphy)

2

Scientists studying the bones of an extinct giant rabbit found on the Mediterranean island of Minorca estimate this prehistoric animal weighed as much as 31 pounds! The largest rabbits alive today– domestic breeds such as the Flemish giant–weigh 22 pounds at most.

Image: A reconstruction of a giant Minorcan rabbit is shown next to a modern European rabbit. (Image by Meike Köhler)

3

Thanks to human introductions the European rabbit (Oryctolagus cuniculus) is found throughout Western Europe, Australia, parts of South America, North Africa and on more than 800 islands around the world. Today in Iberia, Spain, the European rabbit’s sole home for many thousands of years, it is threatened.

Image: A European rabbit. (Image courtesy Encyclopedia of Life)

4

Archaeologists have evidence of people hunting rabbits in the south of France some 120,000 years ago. Scientists suspect even Neanderthals lived on diets made up largely of rabbits.

Painting: “Der November” by Joachim von Sandrat (1606-1688)

5

A “never fail” Kansas folk remedy for reducing fever recommends making a strong tea from the dung of the wild jackrabbit and drinking it every half-hour.

Image: Black-tailed jackrabbit (Photo by Susan E. Adams)

Howler monkey born at National Zoo

John Barrat — Thu, 05 Apr 2012 10:26:59 +0000

Spring is in full swing at the Smithsonian’s National Zoo, and the Small Mammal House—which celebrated the birth of a black howler monkey (Alouatta caraya) March 22—is no exception. Since then, keepers have been monitoring the family at a distance, allowing first-time parents Chula (mother) and Pele (father) to bond with their baby.

The pair has exhibited strong parental skills and the young primate seems bright, alert, and increases its activity and independence day by day. This is the first surviving howler monkey in the Zoo’s history of exhibiting the animal. Its sex has not yet been determined. Zoo visitors can see the howler family on exhibit in the Small Mammal House.

Their thick necks house a unique voice box, including an enlarged hyoid bone, that enables male howler monkeys to penetrate three miles of dense forest with a single rumbling growl. These booming territorial calls have earned the primates, which are native to Central and South America, the title of loudest animal in the New World (North, Central and South America). The International Union for Conservation of Nature lists the black howler monkey as least concern.

Photos by Clyde Nishimura (top) and Janice Sveda, Smithsonian’s National Zoo