What’s Brown And Red and Looks Like A Penguin?

Did you know that penguins didn’t always boast tuxedo-like black-and-white markings, according to a new study. The discovery of the first ancient penguin fossil with evidence of feathers reveals the aquatic birds were not black and white but were once reddish-brown and gray.

The 36 million-year-old fossil represents one of the largest ancient penguins ever found. The bird would have been 5 feet (1.5 meters) tall, and probably weighed twice as much as modern Emperor penguins, which average about 66 pounds (30 kilograms). Its long, grooved beak suggests that, like modern penguins, it hunted by diving for fish. Imprints of feathers in the rock around the bones could help researchers understand how modern penguin feathers evolved, said Julia Clarke, a paleontologist at The University of Texas at Austin and a co-author of the paper.

The fossil, a new species named Inkayacu paracasensis (or “Water King”), was discovered in the Reserva Nacional de Paracas, a desert preserve on the coast of Peru. Researchers in the field noticed evidence of scaly skin on the fossil foot, prompting suspicion that more evidence of soft tissue might have been preserved. When Clarke examined the specimen in the lab, those suspicions proved true.

“I turned over a flake of rock right near one of the wing elements, and right there was our first evidence of feathering,” she told LiveScience. To find out what color those feathers might have been, the researchers examined the shape of the penguin’s melanosomes. These tiny structures resembling pockets contain pigment cells that help give bird feathers their color. The analysis showed that the ancient feathers were likely reddish-brown and gray.

“The plumage of these animals was in a very different palette of what we see in living penguins today,” Clarke said. While comparing the ancient penguin’s melanosomes to modern birds, the researchers noticed another oddity: Modern penguin melanosomes are different from those of other modern birds. They’re broader and clustered in patterns not seen in other species.

Stranger still, the ancient penguin’s melanosomes didn’t match modern penguins’ and instead looked like the melanosomes of other modern birds. The feathers themselves were shaped and stacked like those of modern penguins, suggesting that the ancient penguin had already evolved to swim. The broad melanosomes, however, must have evolved later, perhaps as a way to make feathers more resistant to the wear and tear of swimming underwater, the researchers wrote in the Sept. 20 online edition of the journal Science. Black-and-white coloring would have evolved later, as camouflage from predators like seals that weren’t yet around when the newly discovered penguin species roamed the seas.

“It’s a quite interesting find, because not only the feather preservation, but also because they found a nearly complete skeleton,” said Gerald Mayr, a paleornithologist at the Senckenberg Museum of National History in Germany, who was not involved in the study. However, Mayr said, the theory that physical forces acted on penguin feathers to change the evolution of melanosomes is contradicted by the fact that half of modern penguin feathers are white and contain no melanosomes, despite being subject to the same hydrodynamic forces as melanosome-rich black feathers.

“The main question certainly is, if not due to hydrodynamic forces, why do penguins have such strange melanosomes?” Mayr said. The new fossil is the first chance researchers have had to ask such questions about how penguin feathers evolved to ‘fly’ not in the air, but underwater, Clarke said. “It’s a pretty major transition to go from aerial flight to aquatic flight, to flying in a medium that’s around 800 times denser than air,” Clarke said, adding: “I think there will be more to the story of this penguin’s feathering.”

World’s Oldest Penguin

The Penguin Post has learned that the skull of a 65-million-year-old penguin which spent the last decade wrapped in of all places a newspaper in a Christchurch, New Zealand garage could unlock the secrets of the bird’s evolution. Canterbury Museum scientists are analyzing the new fossil of Waimanu manneringi, named after the Christchurch amateur fossil hunter who was the first to find bones from the world’s oldest penguin. Al Mannering, who first found fossils of the bird at the Waipara River in 1997, made the new find in 2003 but did not realize its significance until preparing it late last year. ”I wrapped it in newspaper and left it in my garage for 10 years, then last year I thought, ‘I’d better have a go at that’. ”Once I realized what it was, I emailed [the museum] straight away.” Canterbury Museum senior curator Paul Scofield said the fossil, from the Paleocene era, was in ”exceptional” condition. ”On a worldwide basis, it would be as good as fossils of this age get.” Scofield said the penguin skull was one of the most important parts of the body for paleontologists, providing valuable hints about the bird’s history and its connection to other penguins. Museum scientists would compare the skull with those of thousands of other penguins to develop a ”family tree” and determine how the bird related to both modern penguins and the dinosaurs. The researchers would also do a CT scan of the skull at Christchurch Hospital, allowing them to reconstruct its brain and outline its abilities and lifestyle. ”As birds become specialists in flight or diving, it changes the way their brain works: now we can start to make guesses at how these animals actually lived,” Scofield said. The museum would work with American scientists from the University of Texas who had found similar fossils in South America, which had recently separated from New Zealand at the age the fossils dated back to. ”It’s a really sexy field in paleontology, because penguins were one of the earliest bird groups to evolve.” Scofield said the Paleocene era was ”absolutely crucial” to scientific understanding of modern birds and mammals, due to dramatic change which occurred during the period. ”As soon as we became free of dinosaurs, evolution went crazy,” he said.

Amateur fossil hunter Al Mannering, who discovered the skull of the world’s oldest penguin, left, which is shown compared with a modern penguin.

Jumbo Penguin Found

The Penguin Post has learned that New Zealand was once home to the tallest penguin species ever known — a lanky, plump bird that stood as high as 4.2 feet (1.3 meters). The penguin, dubbed Kairuku grebneffi, lived about 27 million years ago in a penguin paradise. More of New Zealand was underwater at the time, with only today’s mountaintops emerging from the sea. That made for excellent coastal nesting for a number of penguin species. The new fossil specimens were found beginning in the 1970s, and researchers have continued to turn up bones from the animals as recently as two months ago, said study researcher and North Carolina State University paleontologist Daniel Ksepka. The find expands the known diversity of ancient New Zealand penguins, Ksepka told LiveScience. “In the past we would have thought there were one or two species living in the area,” he said. “Now we know there were five.” Ksepka and his colleagues described Kairuku grebneffi and a second species, Kairuku waitaki, today (Feb. 27) in the Journal of Vertebrate Paleontology. K. grebneffi had unusually long flippers and a slim build, though its legs and feet were as short and stumpy as those of penguins today. Today, penguins tend to cluster in species-specific habitats, with little overlap. Humboldt penguins dominate coastal Peru, for example, while Magellanic penguins are the main species found in Argentina. But researchers are finding that a variety of species lived side-by-side in ancient New Zealand. Ksepka and his colleagues are using these ancient penguins to study everything from brain evolution to how the animals regulate their temperatures in frigid waters. “Penguins are so interesting,” Ksepka said. “They’re so different than other birds that there’s a lot we can do in the fossil record to try to understand how they became what they are.”

Why Penguin Wear Tuxedos

Those tuxedo-wearing birds that inhabit Earth’s coldest continent may have evolved a means of retaining heat when they were still living in warm climates, scientists now suggest. A key adaptation that helped modern penguins to invade the cold waters of Antarctica within the last 16 million years is the so-called humeral arterial plexus, a network of blood vessels that limits heat loss through the wings. The plexus routes blood coming into the body from the wings past the blood traveling from the body to the wings. As such, the cooler blood from the wings, which get cold in the water, is heated up by warmer blood from the body, thus conserving heat. To find out more about how this anatomical structure evolved, scientists investigated seven live penguin species and 19 fossil ones. In live specimens, they found the plexus leaves behind grooves in the upper arm bone called the humerus. As such, they could see when this structure began appearing in extinct penguin species from the fossil record.  Those tuxedo-wearing birds that inhabit Earth’s coldest continent may have evolved a means of retaining heat when they were still living in warm climates, scientists now suggest. A key adaptation that helped modern penguins to invade the cold waters of Antarctica within the last 16 million years is the so-called humeral arterial plexus, a network of blood vessels that limits heat loss through the wings. The plexus routes blood coming into the body from the wings past the blood traveling from the body to the wings. As such, the cooler blood from the wings, which get cold in the water, is heated up by warmer blood from the body, thus conserving heat.

Palaeeudyptes, one of the "giant" penguins lived during the Oligocene, about 28 million years ago. Bones in this bird and its relatives show clear evidence of a heat-conserving structure known as a humeral arterial plexus. Credit: the Geology Museum, University of Otago, Dunedin, New Zealand.

Surprisingly, they found the plexus arose at least 49 million years ago, when the planet was going through a warm “greenhouse Earth” phase due to vast amounts of global warming gases that got pumped into the atmosphere, perhaps by volcanism. “I began this work thinking we would relate heat retention in penguins to the global cooling that took place at the Eocene-Oligocene boundary [about 34 million years ago], whereas in fact, penguins were cold-water-tolerant millions of years earlier,” researcher Daniel Thomas, a paleontologist at the University of Cape Town in South Africa, told the Penguin Post. The earliest known penguins to feature the plexus lived on the lost continent of Gondwana, on what is now Seymour Island in Antarctica. Back then, the waters there were 59 degrees Fahrenheit (15 degrees Celsius), compared with the water’s current average temperature of 34 degrees F (1 degree C). (Scientists can deduce ancient temperatures by looking at the chemistry of fossils — for instance, magnesium levels in the shells of certain organisms rise as temperatures go up.) The researchers suspect the plexus first evolved to help penguins save energy during long foraging trips in the cold water, as the structure evolved in concert with dramatic skeletal changes that promoted buoyancy and reduced drag, thus improving deep-diving and long-distance swimming. As global climate cooled, the plexus then found a new use, proving key to the penguins’ invasion of Antarctic ice sheets. “Penguins have occupied much of the Southern Hemisphere in the last 40 million years because of their tolerance for cold water,” Thomas said.

Giant Penguin Found!

The Penguin Post has learned that scientists have uncovered fossils which reveal the ancestor of the penguin to be a fearsome beast far removed from the waddling bird in dinner-suit plumage which has endeared itself to cinema audiences. The fossils, which were found in Peru, suggest a creature that was more than 5 feet tall and weighed as much as a human. The 36 million-year-old tropical bird’s intimidating appearance was topped off with powerful arms, a chunky neck and a potentially vicious foot long beak. “It’s a monster,” said Professor Julia Clarke, of North Carolina State University, who described the fossils with her team in Proceedings of the National Academy of Sciences. The discovery of the giant bird has shaken scientists’ understanding of penguin evolution. The find indicates that penguins made the journey to equatorial regions much earlier in their evolutionary history than researchers realized. And because the penguins lived during a period when the planet was experiencing a “greenhouse” climate, the pair of species that have been discovered are challenging what researchers thought they knew about how species adapt to hotter temperatures. The giant species has been named Icadyptes salasi. If it were alive today, it would tower over the largest penguins on the planet, the nearly 4 foot tall Emperors, whose epic migration across the Antarctic wilderness to bring food to their chicks was celebrated in the film March of the Penguins. “The bone preservation is extremely good,” Professor Clarke said. The detail is so clear that researchers were able to see fine patterning on the beak of the giant penguin left by a sheet of keratin, the material that makes up feathers. The team does not have any direct evidence for the new discovery’s diet, but the wings were adapted for swimming and found in sediments laid down just off shore. Its elongated beak would have been capable of snaring large fish, but its shape is unusual. “It is distinct from anything we have in living penguins,” Professor Clarke said. Attachment points for neck muscles are also large, suggesting it had a powerful neck for spearing prey. The discovery goes against the general rule that as climatic conditions get warmer, species tend to evolve into a smaller body size. The theory is that large size is useful in the cold because it reduces the ratio of surface area to volume, making it easier to conserve heat. But Icadyptes salasi was found in a region that resembled the modern-day Atacama Desert in Chile. The find contradicts the idea that penguins did not reach equatorial regions until 4 million to 8 million years ago, well after a cooling period had set in that began to swell the polar icecaps. Today, only one species, the Humboldt penguin, is found on the coast of Peru. The team is keen to point out that although these species were adapted to the tropics, it does not mean that current penguin species will be able to adapt quickly to climate change. “Current global warming is occurring on a significantly shorter time scale,” Professor Clarke said.