Fossil for Sale

A missing link in the evolution of the front claw of living scorpions and horseshoe crabs was identified with the discovery of a 390 million-year-old fossil by researchers at Yale and the University of Bonn, Germany.

The specimen, named Schinderhannes bartelsi, was found fossilized in slate from a quarry near Bundenbach in Germany, a site that yields spectacularly durable pyrite-preserved fossils — findings collectively known as the Hunsrück Slate. The Hunsrück Slate has previously produced some of the most valuable clues to understanding the evolution of arthropods – including early shrimp-like forms, a scorpion and sea spiders as well as the ancient arthropods trilobites.

The fossil’s head section has large bulbous eyes, a circular mouth opening and a pair of segmented, opposable appendages with spines projecting inward along their length. The trunk section is made up of 12 segments, each with small appendages, and a long tail spine. Between the head and trunk, there is a pair of large triangular wing-like limbs — that likely propelled the creature like a swimming penguin, according to Briggs. Unlike its ancestors from the Cambrian period, which reached three feet in length, Schinderhannes is only about 4 inches long.

This finding caps almost 20 years of study by Briggs on the Hunsrück Slate. “Sadly, the quarry from which this fabulous material comes has closed for economic reasons, so the only additional specimens that are going to appear now are items that are already in collectors’ hands and that may not have been fully prepared or realized for what they are,” said Briggs.

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The location of the finds is unexpected, because today the birds are only known from the Americas. In the latest edition of Science magazine, Dr Gerald Mayr claims the fossils show many striking resemblances to modern hummingbird groups.

“Fossils of primitive hummingbirds have been found in the Old World before, but it was a great surprise to find a bird that looked so similar to the modern hummingbirds of the Old World,” Dr Mayr, of the Senkenberg Natural History Museum in Frankfurt, told BBC News Online.

More than 30 million years ago in Europe, a hummingbird-like creature hovered over flowering plants, feeding on their nectar. The scientists who discovered the bird named it Eurotrochilius inexpectatus, which roughly translates to “unexpected European hummingbird.”

The surprise is that the fossils, shown here, are the first modern hummingbird-type fossils known from outside the Americas and are millions of years older than those in the New World. The Old World birds were about an inch and a half from head to tail, with beaks and wings ideal for feeding while hovering.

About Hummingbird

Hummingbirds are birds in the family Trochilidae, and are native to the Americas. They are among the smallest of birds, and include the smallest extant bird species, the Bee Hummingbirds.

They can hover in mid-air by rapidly flapping their wings 12-90 times per second (depending on the species). They can also fly backwards, and are the only group of birds able to do so.

Their English name derives from the characteristic hum made by their rapid wing beats. They can fly at speeds exceeding 15 m/s (54 km/h, 34 mi/h).

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Wikipedia

The fossil of a tropical Asian freshwater turtle, found in the Canadian Arctic. The turtle has been named auroral. The discovery, detailed today in the journal Geology, suggests animals migrated from Asia to North America not around Alaska, as once thought, but directly across a freshwater sea floating atop the warm, salty Arctic Ocean. It also provides additional evidence that a rapid influx of carbon dioxide some 90 million years ago was the likely cause of a super-greenhouse effect that created extraordinary heat in the polar region.

The discovery of the Asian freshwater tropical turtle fossil in the Canadian Arctic raised the question of how exactly it wound up there. After all, a saltwater ocean separates Asia from North America. The scientists who made the discovery said the fossil dates to about 90 million years ago, a time when massive volcanic eruptions appear to have triggered a bout of super greenhouse warming.

The rapid warming, the scientists suspect, allowed meltwater to pour off the continents into the Arctic Ocean. Because fresh water is less dense than salt water, it may have rested on top of the marine water, creating a freshwater pathway for the turtle’s migration.

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The 47.5 million-year-old fossils, discovered in Pakistan in 2000 and 2004 and studied at the University of Michigan, are described in a paper published Feb. 4 in the online journal PLoS.

U-M paleontologist Philip Gingerich, who led the team that made the discoveries, was at first perplexed by the assortment of adult female and fetal bones found together. “When I first saw the small teeth in the field, I thought we were dealing with a small adult whale, but then we continued to expose the specimen and found ribs that seemed too large to go with those teeth,” he said. “By the end of the day, I realized we had found a female whale with a fetus.”

The 8.5-foot-long male specimen, collected four years later from the same fossil beds, shares characteristic anatomical features with the female of the species, but its virtually complete skeleton is 12 percent larger overall, and its canine teeth or fangs 20 percent larger. Such size discrepancies are not uncommon among whales and their kin; in some species the females are larger, while in others the males are slightly to considerably bigger. The size difference of male and female Maiacetus is only moderate, hinting that the males didn’t control territories or command harems of females.

The whales’ big teeth, well-suited for catching and eating fish, suggest the animals made their livings in the sea, probably coming onto land only to rest, mate and give birth, said Gingerich, who is the Ermine Cowles Case Collegiate Professor of Paleontology and director of the U-M Museum of Paleontology. Like other primitive archaeocetes, Maiacetus had four legs modified for foot-powered swimming, and although these whales could support their weight on their flipper-like limbs, they probably couldn’t travel far on land.

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Sophisticated computer scans of fossils have helped solve a mystery over the nature of a giant, ancient raptor known as the Haast’s eagle which became extinct about 500 years ago, researchers said Friday.

The researchers say they have determined that the eagle – which lived in the mountains of New Zealand and weighed about 40 pounds (18 kilograms) – was a predator and not a mere scavenger as many thought.

Much larger than modern eagles, Haast’s eagle would have swooped to prey on flightless birds – and possibly even the rare unlucky human.

Using computed axial tomography, or CAT, the researchers scanned several skulls, a pelvis and a beak in an effort to reconstruct the size of the bird’s brain, eyes, ears and spinal cord.

They compared their data on the Haast’s eagle to characteristics of modern predator birds and scavenger birds to determine that the bird was a fearsome predator that ate the flightless moa birds and even humans.

Scientists believe the Haast’s eagle became extinct about 500 years ago, most likely due to habitat destruction and the extinction of its prey species at the hands of early Polynesian settlers. Before the humans colonized New Zealand about 750 years ago, the largest inhabitants were birds like the Haast’s eagle and the moa.

Scofield said the findings are similar to what he found in Maori folk tales. “The science supports Maori mythology of the legendary pouakai or hokioi, a huge bird that could swoop down on people in the mountains and was capable of killing a small child,” he said.

New Zealand paleontologist Trevor Worthy said the study did a good job of proving the eagle was a killer.

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