As long as dinosaurs have been known, there has been speculation about their appearance. Fossil feathers can preserve the morphology of color-imparting melanosomes, which allows color patterns in feathered dinosaurs to be reconstructed. Here, we map feather color patterns in a Late Jurassic basal paravian theropod dinosaur. Quantitative comparisons with melanosome shape and density in extant feathers indicate that the body was gray and dark and the face had rufous speckles. The crown was rufous, and the long limb feathers were white with distal black spangles. The evolution of melanin-based within-feather pigmentation patterns may coincide with that of elongate pennaceous feathers in the common ancestor of Maniraptora, before active powered flight. Feathers may thus have played a role in sexual selection or other communication.

image source 1
sciencemag.org

Australian scientists have confirmed the oldest penis-like structure in an ancient fish specimen.

The discovery of the 400 million-year-old reproductive organ is one of the earliest examples of internal fertilisation in vertebrate animals.

And understanding the anatomy of these ancient fish could reveal further details in the evolution of vertebrates- including humans.

The research is published in today’s advanced online ahead of print edition of _Nature_.

Earlier this year the team, led by Australian palaeontologist Dr John Long, predicted some ancient fish from the Devonian era, had an attachment to their pelvic bone, which were used by males to fertilise females.

Long, of Museum Victoria, says “when we announced we’d found some structures in the pelvic fin that suggested copulation, we hadn’t found the business end of how they were doing it.”

Now the team have identified a long clasper, made entirely of bone, on another fish specimen.

Long says claspers were used by the ancient fish, an extinct class of armoured fish called placoderms, to grip inside the female while they were mating.

“It’s a pretty big find because placaderms were the dominant fish for 70 million years, but we knew nothing about their reproduction,” says Long.

Similar to sharks

He says their work earlier this year suggests the reproductive structure in the dominant group of placoderms, called arthrodires, was similar to present day sharks.

“Now we’ve actually found it, a specimen with an undoubted clasper with a knobbly end.”

Study author and palaeontologist Dr Kate Trinajstic, of Curtin University in Perth, says the clasper was discovered in a fish specimen uncovered in the Gogo region of Western Australia in 2001.

She says the team originally discounted the bone as the reproductive organ because they thought it was part of the pelvic gurdle.

On closer inspection, Trinajstic says they realised it was a sexual organ.

“We were surprised because it’s so big,” she says. “We were expecting something smaller.”

Trinajstic says the clasper, which was attached to the pelvic organ would have been erectile.

“It penetrates the female, and acts like a funnel, allowing the transfer of sperm.”

She says the ancient fish had quite advanced reproductive systems considering sharks today have a similar system.

Trinajstic says the discovery of the clasper now allows scientists to identify the sex of other specimens of ancient fish.

“That sounds like a basic thing, but we haven’t been able to do that before.”
au.news.yahoo.com

Uncovered: 350-year-old picture of dodo before it was extinct

A previously undiscovered 17th century picture of a dodo, drawn before the bird became extinct, is to be sold at auction by Christie’s.

The drawing, which dates from the late 1600s, offers a rare insight into the appearance of the flightless bird that was the first recorded casualty of human interference in the habitat of other creatures.

Dodos were the main predators on Mauritius until settlers introduced bigger animals to Indian Ocean island, including pigs. Many were shipped to Europe as curiosities or had their nesting areas destroyed and the species was extinct by 1700.

The inscription above the bird, ‘Dronte’, was the Dutch 17th-century name for the dodo

The 350-year-old drawing, described by Christie’s as “vibrant”, is one of a small number of images of the unfortunate bird whose demise was largely unnoticed until a dodo featured in Lewis Carroll’s popular 1865 book Alice’s Adventures in Wonderland.

Painted by an unknown artist of the 17th century Dutch school in about 1650, the unframed 10×8 inch picture is expected to fetch up to £6,000 when it is sold by Christie’s in London on July 9.

The auction house believes it differs from existing images, many of which were drawn from a small number of dodos that were put on display in Europe, some of which were later stuffed.

Little is known about the origin of the picture, which has never before been published.

The inscription above the bird, ‘Dronte’, was the Dutch 17th-century name for the dodo, although at this period it was also used in a number of other languages including French, German and Italian.

Julian Hume, a dodo expert and a palaeontologist at the Natural History Museum, said the image was “very interesting but rather odd”.

“The lack of tail is anatomically correct – the ostrich-like plumes normally depicted are exaggerations – but this may be a fault by the artist,” he said. “The angle of the dodo is also novel, showing a 3D pose rather than the usual side view.”

He added that it was likely to have been copied from earlier drawings. “The image is somewhat based on Roelandt Savery’s 1626 image of the dodo standing by a rock. We know so little about the number of transported live dodo specimens, and coupled with repeated plagiarism of images, factual determination is almost impossible to obtain.”

Another dodo expert, Anthony Cheke, said: “There is always a lot of interest in artefacts like these because the dodo is such a curiosity. This is certainly an unusual image although the drawing is, frankly, not very good even by contemporary standards.”

telegraph.co.uk