Dinosaur brains from baby to adult

New research by a University of Bristol palaeontology post-graduate student has revealed fresh insights into how the braincase of the dinosaur Psittacosaurus developed and how this tells us about its posture.

Psittacosaurus was a very common dinosaur in the Early Cretaceous period — 125 million years ago — that lived in eastern Asia, especially north-east China.

Hundreds of samples have been collected which show it was a beaked plant-eater, an early representative of the Ceratopsia, which had later relatives with great neck frills and face horns, such as Triceratops.

The babies hatched out as tiny, hamster-sized beasts and grew to two metres long as adults.

As they grew, the brain changed in shape, from being crammed into the back of the head, behind the huge eyes in the hatchling, to being longer, and extending under the skull roof in the adults.

The braincase also shows evidence for a change in posture as the animals grew. There is good evidence from the relative lengths of the arms and legs, that baby Psittacosaurus scurried about on all fours, but by the age of two or three, they switched to a bipedal posture, standing up on their elongate hind legs and using their arms to grab plant food.

Claire Bullar from the University of Bristol’s School of Earth Sciences led the new research which has been published this week in PeerJ.

She said: “I was excited to see that the orientation of the semi-circular canals changes to show this posture switch.

“The semi-circular canals are the structures inside our ears that help us keep balance, and the so-called horizontal semi-circular canal should be just that — horizontal — when the animal is standing in its normal posture.

“This is just what we see, with the head of Psittacosaurus pointing down and forwards when it was a baby — just right for moving on all-fours. Then, in the teen or adult, we see the head points exactly forwards, and not downwards, just right for a biped.”

Co-supervisor Dr Qi Zhao from the Institute of Vertebrate Palaeontology and Palaeoanthropology (IVPP) in Beijing, where the specimens are housed, added: “It’s great to see our idea of posture shift confirmed, and in such a clear-cut way, from the orientation of the horizontal ear canal.

“It’s also amazing to see the results of high-quality CT scanning in Beijing and the technical work by Claire to get the best 3D models from these scan data.”

Professor Michael Ryan of Carleton University, Ottawa, Canada, another collaborator, said: “This posture shift during growth from quadruped to biped is unusual for dinosaurs, or indeed any animal. Among dinosaurs, it’s more usual to go the other way, to start out as a bipedal baby, and then go down on all fours as you get really huge.

“Of course, adult Psittacosaurus were not so huge, and the shift maybe reflects different modes of life: the babies were small and vulnerable and so probably hid in the undergrowth, whereas bipedalism allowed the adults to run faster and escape their predators.”

Professor Michael Benton, also from the University of Bristol’s School of Earth Sciences and another collaborator, added: “This is a great example of classic, thorough anatomical work, but also an excellent example of international collaboration.

“The Bristol Palaeobiology Research Group has a long-standing collaboration with IVPP, and this enables the mix of excellent specimens and excellent research.

“Who would have imagined we could reconstruct posture of dinosaurs from baby to adult, and with multiple lines of evidence to confirm we got it right.”


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Extinct Caribbean bird yields DNA after 2,500 years in watery grave

Scientists have recovered the first genetic data from an extinct bird in the Caribbean, thanks to the remarkably preserved bones of a Creighton’s caracara from a flooded sinkhole on Great Abaco Island.

Studies of ancient DNA from tropical birds have faced two formidable obstacles. Organic material quickly degrades when exposed to heat, light and oxygen. And birds’ lightweight, hollow bones break easily, accelerating the decay of the DNA within.

But the dark, oxygen-free depths of a 100-foot blue hole known as Sawmill Sink provided ideal preservation conditions for the bones of Caracara creightoni, a species of large carrion-eating falcon that disappeared soon after humans arrived in the Bahamas about 1,000 years ago.

Florida Museum of Natural History postdoctoral researcher Jessica Oswald extracted and sequenced genetic material from a 2,500-year-old C. creightoni femur from the blue hole. Because ancient DNA is often fragmented or missing, Oswald had modest expectations for what she would find — maybe one or two genes. But instead, the bone yielded 98.7% of the bird’s mitochondrial genome, the set of DNA that most living things inherit only from their mothers.

“I was super excited. I would have been happy to get that amount of coverage from a fresh specimen,” said Oswald, lead author of a study describing the work and also a postdoctoral researcher at the University of Nevada, Reno. “Getting DNA from an extinct bird in the tropics is significant because it hasn’t been successful in many cases or even tried.”

The mitochondrial genome showed that C. creightoni is closely related to the two remaining caracara species alive today: the crested caracara, Caracara cheriway, and the southern caracara, Caracara plancus. The three species last shared a common ancestor between 1.2 and 0.4 million years ago.

At least six species of caracara once cleaned carcasses and picked off small prey in the Caribbean. But the retreat of glaciers 15,000 years ago and the resulting rise in sea levels triggered extinctions of many birds, said David Steadman, Florida Museum curator of ornithology.

C. creightoni managed to survive the sweeping climatic changes, but the arrival of people on the islands ultimately heralded the species’ demise, as the tortoises, crocodiles, iguanas and rodents that the caracara depended on for food swiftly disappeared.

“This species would still be flying around if it weren’t for humans,” Steadman said. “We’re using ancient DNA to study what should be modern biodiversity.”

Today, the islands host only a fraction of the wildlife that once flourished in the scrubland, forests and water. But blue holes like Sawmill Sink can offer a portal into the past. Researchers have collected more than 10,000 fossils from the sinkhole, representing nearly 100 species, including crocodiles, tortoises, iguanas, snakes, bats and more than 60 species of birds.

Sawmill Sink’s rich store of fossils was discovered by cave diver Brian Kakuk in 2005 in his quest for horizontal passages in the limestone. The hole was not a popular diving spot: Thirty feet below the surface lay a 20-foot-thick layer of saturated hydrogen sulfide, an opaque mass that not only smells of rotten egg, but also reacts with the freshwater above it to form sulfuric acid, which causes severe chemical burns.

After multiple attempts, Kakuk, outfitted with a rebreather system and extra skin protection, punched through the hydrogen sulfide. His lamp lit up dozens of skulls and bones on the blue hole’s floor.

Soon after, Kakuk and fellow cave diver Nancy Albury began an organized diving program in Sawmill Sink.

“This was found by someone who recognized what it was and never moved anything until it was all done right,” Steadman said.

Though the hydrogen sulfide layer presented a foul problem for divers, it provided excellent insulation for the fossils below, blocking UV light and oxygen from reaching the lower layer of water. Among the crocodile skulls and tortoise shells were the C. creightoni bones, including an intact skull.

“For birds, having an entire head of an extinct species from a fossil site is pretty mind-blowing,” Oswald said. “Because all the material from the blue hole is beautifully preserved, we thought at least some DNA would probably be there.”

Since 2017, Oswald has been revitalizing the museum’s ancient DNA laboratory, testing methods and developing best practices for extracting and analyzing DNA from fossils and objects that are hundreds to millions of years old.

Ancient DNA is a challenging medium because it’s in the process of degradation. Sometimes only a minute quantity of an animal’s original DNA — or no DNA at all — remains after bacteria, fungi, light, oxygen, heat and other environmental factors have broken down an organism.

“With ancient DNA, you take what you can get and see what works,” Oswald said. “Every bone has been subjected to slightly different conditions, even relative to other ones from the same site.”

To maximize her chance of salvaging genetic material, Oswald cleans a bone, freezes it with liquid nitrogen and then pulverizes it into powder with a rubber mallet.

“It’s pretty fun,” she said.

While previous studies required large amounts of bone, Oswald’s caracara work showed ancient DNA could be successfully recovered at a smaller scale.

“This puts an exclamation point on what’s possible with ancient DNA,” said Robert Guralnick, Florida Museum curator of bioinformatics. “We have new techniques for looking at the context of evolution and extinction. Beyond the caracara, it’s cool that we have an ancient DNA lab that’s going to deliver ways to look at questions not only from the paleontological perspective, but also at the beginnings of a human-dominated planet.”

Steadman, who has spent decades researching modern and extinct biodiversity in the Caribbean, said some questions can only be answered with ancient DNA.

“By understanding species that weren’t able to withstand human presence, it helps us better appreciate what we have left — and not just appreciate it, but understand that when these species evolved, there were a lot more things running and flying around than we have today.”

Other co-authors are Julia Allen of the University of Nevada, Reno; Kelsey Witt of the University of California, Merced; Ryan Folk of the Florida Museum and Nancy Albury of the National Museum of the Bahamas.


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Researchers discover oldest fossil forest in Asia

The Devonian period, which was 419 million to 359 million years ago, is best known for Tiktaalik, the lobe-finned fish that is often portrayed pulling itself onto land. However, the “age of the fishes,” as the period is called, also saw evolutionary progress in plants. Researchers reporting August 8 in the journal Current Biology describe the largest example of a Devonian forest, made up of 250,000 square meters of fossilized lycopsid trees, which was recently discovered near Xinhang in China’s Anhui province. The fossil forest, which is larger than Grand Central Station, is the earliest example of a forest in Asia.

Lycopsids found in the Xinhang forest resembled palm trees, with branchless trunks and leafy crowns, and grew in a coastal environment prone to flooding. These lycopsid trees were normally less than 3.2 meters tall, but the tallest was estimated at 7.7 meters, taller than the average giraffe. Giant lycopsids would later define the Carboniferous period, which followed the Devonian, and become much of the coal that is mined today. The Xinhang forest depicts the early root systems that made their height possible. Two other Devonian fossil forests have been found: one in the United States, and one in Norway.

“The large density as well as the small size of the trees could make Xinhang forest very similar to a sugarcane field, although the plants in Xinhang forest are distributed in patches,” says Deming Wang, a professor in the School of Earth and Space Sciences at Peking University, co-first author on the paper along with Min Qin of Linyi University. “It might also be that the Xinhang lycopsid forest was much like the mangroves along the coast, since they occur in a similar environment and play comparable ecologic roles.”

The fossilized trees are visible in the walls of the Jianchuan and Yongchuan clay quarries, below and above a four-meter thick sandstone bed. Some fossils included pinecone-like structures with megaspores, and the diameters of fossilized trunks were used to estimate the trees’ heights. The authors remarked that it was difficult to mark and count all the trees without missing anything.

“Jianchuan quarry has been mined for several years and there were always some excavators working at the section. The excavations in quarries benefit our finding and research. When the excavators stop or left, we come close to the highwalls and look for exposed erect lycopsid trunks,” says Wang, who, with Qin, found the first collection of fossil trunks in the mine in 2016. “The continuous finding of new in-situ tree fossils is fantastic. As an old saying goes: the best one is always the next one.”

This work was supported by The National Natural Science Foundation of China.


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NZ big bird a whopping ‘squawkzilla’

Australasian palaeontologists have discovered the world’s largest parrot, standing up to 1m tall with a massive beak able to crack most food sources.

The new bird has been named Heracles inexpectatus to reflect its Herculean myth-like size and strength — and the unexpected nature of the discovery.

“New Zealand is well known for its giant birds,” says Flinders University Associate Professor Trevor Worthy. “Not only moa dominated avifaunas, but giant geese and adzebills shared the forest floor, while a giant eagle ruled the skies.

“But until now, no-one has ever found an extinct giant parrot — anywhere.”

The NZ fossil is approximately the size of the giant ‘dodo’ pigeon of the Mascarenes and twice the size of the critically endangered flightless New Zealand kakapo, previously the largest known parrot.

Like the kakapo, it was a member of an ancient New Zealand group of parrots that appear to be more primitive than parrots that thrive today on Australia and other continents.

Experts from Flinders University, UNSW Sydney and Canterbury Museum in New Zealand estimate Heracles to be 1 m tall, weighing about 7 kg.

The new parrot was found in fossils up to 19 million years old from near St Bathans in Central Otago, New Zealand, in an area well known for a rich assemblage of fossil birds from the Miocene period.

“We have been excavating these fossil deposits for 20 years, and each year reveals new birds and other animals,” says Associate Professor Worthy, from the Flinders University Palaeontology Lab.

“While Heracles is one of the most spectacular birds we have found, no doubt there are many more unexpected species yet to be discovered in this most interesting deposit.”

“Heracles, as the largest parrot ever, no doubt with a massive parrot beak that could crack wide open anything it fancied, may well have dined on more than conventional parrot foods, perhaps even other parrots,” says Professor Mike Archer, from the UNSW Sydney Palaeontology, Geobiology and Earth Archives (PANGEA) Research Centre.

“Its rarity in the deposit is something we might expect if it was feeding higher up in the food chain,” he says, adding parrots “in general are very resourceful birds in terms of culinary interests.”

“New Zealand keas, for example, have even developed a taste for sheep since these were introduced by European settlers in 1773.”

Birds have repeatedly evolved giant species on islands. As well as the dodo, there has been another giant pigeon found on Fiji, a giant stork on Flores, giant ducks in Hawaii, giant megapodes in New Caledonia and Fiji, giant owls and other raptors in the Caribbean.

Heracles lived in a diverse subtropical forest where many species of laurels and palms grew with podocarp trees.

“Undoubtedly, these provided a rich harvest of fruit important in the diet of Heracles and the parrots and pigeons it lived with. But on the forest floor Heracles competed with adzebills and the forerunners of moa,” says Professor Suzanne Hand, also from UNSW Sydney.

“The St Bathans fauna provides the only insight into the terrestrial birds and other animals that lived in New Zealand since dinosaurs roamed the land more than 66 million years ago,” says Paul Scofield, Senior Curator at Canterbury Museum, Christchurch.

Canterbury Museum research curator Vanesa De Pietri says the fossil deposit reveals a highly diverse fauna typical of subtropical climates with crocodilians, turtles, many bats and other mammals, and over 40 bird species.

“This was a very different place with a fauna very unlike that which survived into recent times,” she says.

This research was funded by the Australian Research Council and supported by the Marsden Fund Council from Government funding, managed by Royal Society Te Ap?rangi.


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New species of dinosaur discovered after lying misidentified in fossil vaults for 30 years

A PhD student of the University of the Witwatersrand, South Africa, has discovered a new dinosaur species in the University’s vaults, after it has been laying misidentified in a collection for 30 years.

The team of scientists, led by PhD Student Kimberley Chapelle, recognised that the dinosaur was not only a new species of sauropodomorph, but an entirely new genus. The specimen has now been named Ngwevu intloko which means “grey skull” in the Xhosa language, chosen to honour South Africa’s heritage. She was joined in the research by her PhD supervisors: Prof Jonah Choiniere (Wits), Dr Jennifer Botha (National Museum Bloemfontein), and Professor Paul Barrett (Natural History Museum, London). Together, Kimberley and these world-leading researchers have been improving knowledge of South African palaeontology for the last six years. The dinosaur has been described in the academic journal, PeerJ.

Professor Paul Barrett, Chapelle’s PhS supervisor and researcher at the Natural History Museum in the UK explains, “This is a new dinosaur that has been hiding in plain sight.” “The specimen has been in the collections in Johannesburg for about 30 years, and lots of other scientists have already looked at it. But they all thought that it was simply an odd example of Massospondylus.”

Massospondylus was one of the first dinosaurs to reign at the start of the Jurassic period. Regularly found throughout southern Africa, these animals belonged to a group called the sauropodomorphs and eventually gave rise to the sauropods, a group containing the Natural History Museum’s iconic dinosaur cast Dippy. Researchers are now starting to look closer at many of the supposed Massospondylus specimens, believing there to be much more variation than first thought.

Kimberley Chapelle explains why the team were able to confirm that this specimen was a new species, “In order to be certain that a fossil belongs to a new species, it is crucial to rule out the possibility that it is a younger or older version of an already existing species. This is a difficult task to accomplish with fossils because it is rare to have a complete age series of fossils from a single species. Luckily, the most common South African dinosaur Massospondylus has specimens ranging from embryo to adult. Based on this, we were able to rule out age as a possible explanation for the differences we observed in the specimen now named Ngwevu intloko.”

The new dinosaur has been described from a single fairly complete specimen with a remarkably well-preserved skull. The new dinosaur was bipedal with a fairly chunky body, a long slender neck and a small, boxy head. It would have measured three metres from the tip of its snout to the end of its tail and was likely an omnivore, feeding on both plants and small animals.

The findings will help scientists better understand the transition between the Triassic and Jurassic period, around 200 million years ago. Known as a time of mass extinction it now seems that more complex ecosystems were flourishing in the earliest Jurassic than previously thought.

“This new species is interesting,” says Prof Barrett, “because we thought previously that there was really only one type of sauropodomorph living in South Africa at this time. We now know there were actually six or seven of these dinosaurs in this area, as well as variety of other dinosaurs from less common groups. It means that their ecology was much more complex than we used to think. Some of these other sauropodomorphs were like Massospondylus, but a few were close to the origins of true sauropods, if not true sauropods themselves.”

This work shows the value of revisiting specimens in museum collections, as many news species are probably sitting unnoticed in cabinets around the world.


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A voracious Cambrian predator, Cambroraster, is a new species from the Burgess Shale

Palaeontologists at the Royal Ontario Museum and University of Toronto have uncovered fossils of a large new predatory species in half-a-billion-year-old rocks from Kootenay National Park in the Canadian Rockies. This new species has rake-like claws and a pineapple-slice-shaped mouth at the front of an enormous head, and it sheds light on the diversity of the earliest relatives of insects, crabs, spiders, and their kin. The findings were announced July 31, 2019, in a study published in Proceedings of the Royal Society B.

Reaching up to a foot in length, the new species, named Cambroraster falcatus, comes from the famous 506-million-year-old Burgess Shale. “Its size would have been even more impressive at the time it was alive, as most animals living during the Cambrian Period were smaller than your little finger,” said Joe Moysiuk, a graduate student based at the Royal Ontario Museum who led the study as part of his PhD research in Ecology & Evolutionary Biology at the University of Toronto. Cambrorasterwas a distant cousin of the iconic Anomalocaris, the top predator living in the seas at that time, but it seems to have been feeding in a radically different way,” continued Moysiuk.

The name Cambroraster refers to the remarkable claws of this animal, which bear a parallel series of outgrowths, looking like forward-directed rakes. “We think Cambroraster may have used these claws to sift through sediment, trapping buried prey in the net-like array of hooked spines,” added Jean-Bernard Caron, Moysiuk’s supervisor and the Richard M. Ivey Curator of Invertebrate Palaeontology at the Royal Ontario Museum.

With the interspace between the spines on the claws at typically less than a millimeter, this would have enabled Cambroraster to feed on very small organisms, although larger prey could also likely be captured, and ingested into the circular tooth-lined mouth. This specialized mouth apparatus is the namesake of the extinct group Radiodonta, which includes both Cambroraster and Anomalocaris. Radiodonta is considered to be one of the earliest offshoots of the arthropod lineage (today including all animals with an exoskeleton, a segmented body and jointed limbs).

The second part of the species name falcatus was given in tribute to another of Cambroraster‘s distinctive features: the large shield-like carapace covering its head, which is shaped like the Millennium Falcon spaceship from the Star Wars films. “With its broad head carapace with deep notches accommodating the upward facing eyes, Cambroraster resembles modern living bottom-dwelling animals like horseshoe crabs. This represents a remarkable case of evolutionary convergence in these radiodonts,” Moysiuk explained. Such convergence is likely reflective of a similar environment and mode of life — like modern horseshoe crabs, Cambroraster may have used its carapace to plough through sediment as it fed.

Perhaps even more astonishing is the large number of specimens recovered. “The sheer abundance of this animal is extraordinary,” added Dr. Caron, who is also an Assistant Professor in Ecology & Evolutionary Biology and Earth Sciences at the University of Toronto, and the leader of the field expeditions that unearthed the new fossils. “Over the past few summers we found hundreds of specimens, sometimes with dozens of individuals covering single rock slabs.”

Based on over a hundred exceptionally well-preserved fossils now housed at the Museum, researchers were able to reconstruct Cambroraster in unprecedented detail, revealing characteristics that had not been seen before in related species.

“The radiodont fossil record is very sparse; typically, we only find scattered bits and pieces. The large number of parts and unusually complete fossils preserved at the same place are a real coup, as they help us to better understand what these animals looked like and how they lived,” said Dr. Caron. “We are really excited about this discovery. Cambroraster clearly illustrates that predation was a big deal at that time with many kinds of surprising morphological adaptations.”

Fossils from the Cambrian period, particularly from sites like the Burgess Shale, record a dramatic “explosion” of biodiversity at this time, culminating in the evolution of most of the major groups of animals that survive today. But, the story has far more intricacy than a straight line leading from simple ancestors to the vast diversity of modern species. “Far from being primitive, radiodonts show us that at the very outset of complex ecosystems on Earth, early representatives of the arthropod lineage rapidly radiated to play a wide array of ecological roles,” remarked Moysiuk.

The fossils were found at several sites in the Marble Canyon area in Kootenay National Park, British Columbia, which have been discovered by ROM-led field teams since 2012, with some of the key specimens unearthed just last summer. These sites are about 40 kilometers away from the original Burgess Shale fossil site in Yoho National Park that was first discovered in 1909. What is also exciting for researchers is the realization that there is a large new area in northern Kootenay National Park worth scientific exploration, holding the potential for the discovery of many more new species.

The Burgess Shale fossil sites are located within Yoho and Kootenay National Parks and are managed by Parks Canada. Parks Canada is proud to work with leading scientific researchers to expand our knowledge and understanding of this key period of earth history and to share these sites with the world through award-winning guided hikes. The Burgess Shale was designated a UNESCO World Heritage Site in 1980 due to its outstanding universal value, and is now part of the larger Canadian Rocky Mountain Parks World Heritage Site.

The discovery and study of Cambroraster will be profiled in the upcoming CBC’s The Nature of Things episode “First Animals” airing October 18, 2019 at 9 p.m. and on the free CBC Gem streaming service. These and other Burgess Shale specimens will be showcased in a brand-new gallery at the Royal Ontario Museum, the Willner Madge Gallery of the Dawn of Life, expected to open in 2021. Starting this summer, select specimens of Cambroraster will be put on display in the New Research case within the current temporary Willner Madge Gallery, Dawn of Life Preview exhibition.

Major funding support for the research and field work came from the Natural Sciences and Engineering Research Council of Canada (Discovery Grant #341944), the Royal Ontario Museum, the National Geographic Society (#9475-14), the Swedish Research Council (to Michael Streng), the National Science Foundation (NSF-EAR-1554897) and Pomona College (to Robert R. Gaines). Moysiuk’s PhD research is also supported by an NSERC Canada Graduate Scholarship (CGSM).


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Paleontology: New light on cichlid evolution in Africa

Cichlids (Cichlidae) are a group of small to medium-sized fish that are ubiquitous in freshwater habitats in the tropics. They are particularly notable in exhibiting a wide range of morphological and behavioral specializations, such as various modes of parental care, including mouthbrooding. Some species (mainly members of the genus Tilapia) have achieved fame as culinary delicacies and are of considerable economic significance. Cichlids have undergone rapid diversification in Africa, which is home to at least 1100 species. This process has been especially prominent in the Great Lakes in East Africa’s Rift Valley (Lakes Tanganyika, Malawi and Victoria), where it is referred to as the East African Radiation.

“Cichlid diversification in East Africa has become a central paradigm in evolutionary biology. As a consequence, dating the onset of the process and understanding the mechanisms that drive it are issues of great interest to evolutionary biologists and paleobiologists,” says LMU paleontologist Professor Bettina Reichenbacher, who is also member of the GeoBio-Center at LMU. Fossils from the area provide the sole source of direct evidence that would allow one to determine the timing and trace the course of lineage diversification within the group. However, the search for cichlid fossils has proven to be both arduous and extremely time- consuming. Indeed, only about 20 fossil species of cichlids from Africa have yet been formally described.

In a study that appears in the online journal Scientific Reports, a team of researchers led by Bettina Reichenbacher now describes a new fossil cichlid, which the authors assign to the new genus Oreochromimos. The name derives from the fact that the specimens, which the team discovered in Central Kenya, show similarities to members of the Tribe Oreochromini (hence the element ‘mimos’, meaning ‘mimic’, in the genus name), which are widely distributed in Africa today. “Determining whether or not the fossils could be assigned to any of the extant cichlid lineages was particularly challenging,” says Stefanie Penk, first author of the study and a doctoral student in Reichenbacher’s group. The difficulties are rooted in the great diversity of the modern cichlid fauna in Africa, and the fact that even distantly related species may be morphologically very similar to each other. “The architecture of the skeleton in cichlids is pretty conservative. All of them have a similar basic form, which undergoes very little change during speciation,” Reichenbacher explains. In collaboration with Dr. Ulrich K. Schliewen, co-author of the new paper, Curator of Fishes at the Bavarian State Collection for Zoology in Munich (SNSB-ZSM) and also a member of the GeoBio-Center at LMU, the team adopted the ‘best-fit approach’ to the classification of the fossil specimens. This requires comparison of the fossil material with all the relevant modern lineages of cichlids. In light of their contemporary diversity, that might seem an impossible task. But thanks to Schliewen’s knowledge — and the range of comparative material represented in the collection under his care — the strategy succeeded.

A unique glimpse of the past

Reichenbacher and colleagues recovered the Oreochromimosmaterial from a fossil-fish Lagerstätte in Kenya’s Tugen Hills, which lie within the Eastern Branch of the East African Rift System. This site provides a unique window into the region’s past. The volcanic and sedimentary rocks deposited here date back 5-20 million years. They were overlain by younger material and subsequently uplifted to altitudes of as much as 2000 m by tectonic forces. As a result, the fossil-bearing rocks exposed in the Tugen Hills are either inaccessible to exploration or have been lost to erosion in other parts of Africa. Consequently, the strata here contain a unique assemblage of fossils. Undoubtedly the best known finds so far excavated are the 6-million-year-old remains of a hominin species, which has been named Orrorin tugenensis (orrorin means ‘original man’ in the local language). But cichlid fossils are also among the paleontological treasures preserved in these sedimentary formations — and they are at the heart of Reichenbacher’s Kenya Project, which began in 2011. The material collected so far was recovered in cooperation with Kenya’s Egerton University, and is now on loan to LMU’s Department of Earth and Environmental Sciences for further study.

The Oreochromimos specimens are about 12.5 million years old, which makes this genus the oldest known fossil representative of the Tribe Oreochromini. It therefore qualifies as the oldest fossil clade yet assigned to the Haplotilapiini, the lineage which gave rise not only to most of the species that constitute the present-day diversity of African cichlids, but also to the East African Cichlid Radiation in the Great Lakes of the Rift Valley. With their use of an innovative approach to comparative systematics, the authors of the new study have provided a basis for the taxonomic assignment of future finds of fossil cichlid material. “With the aid of this dataset, it will be possible to classify fossil cichlids much more reliably than before and thus to shed new light on their evolutionary history,” says Bettina Reichenbacher.


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World’s smallest fossil monkey found in Amazon jungle

A team of Peruvian and American scientists have uncovered the 18-million-year-old remains of the smallest fossil monkey ever found.

A fossilized tooth found in Peru’s Amazon jungle has been identified as belonging to a new species of tiny monkey no heavier than a hamster.

The specimen is important because it helps bridge a 15-million-year gap in the fossil record for New World monkeys, says a team led by Duke University and the National University of Piura in Peru.

The new fossil was unearthed from an exposed river bank along the Río Alto Madre de Dios in southeastern Peru. There, researchers dug up chunks of sandstone and gravel, put them in bags, and hauled them away to be soaked in water and then strained through sieves to filter out the fossilized teeth, jaws, and bone fragments buried within.

The team searched through some 2,000 pounds of sediment containing hundreds of fossils of rodents, bats and other animals before they spotted the lone monkey tooth.

“Primate fossils are as rare as hen’s teeth,” said first author Richard Kay, a professor of evolutionary anthropology at Duke who has been doing paleontological research in South America for nearly four decades.

A single upper molar, the specimen was just “double the size of the head of a pin” and “could fall through a window screen,” Kay said.

Paleontologists can tell a lot from monkey teeth, particularly molars. Based on the tooth’s relative size and shape, the researchers think the animal likely dined on energy-rich fruits and insects, and weighed in at less than half a pound — only slightly heavier than a baseball. Some of South America’s larger monkeys, such as howlers and muriquis, can grow to 50 times that heft.

“It’s by far the smallest fossil monkey that’s ever been found worldwide,” Kay said. Only one monkey species alive today, the teacup-sized pygmy marmoset, is smaller, “but barely,” Kay said.

In a paper published online July 23 in the Journal of Human Evolution, the team dubbed the animal Parvimico materdei, or “tiny monkey from the Mother of God River.”

Now stored in the permanent collections of the Institute of Paleontology at Peru’s National University of Piura, the find is important because it’s one of the few clues scientists have from a key missing chapter in monkey evolution.

Monkeys are thought to have arrived in South America from Africa some 40 million years ago, quickly diversifying into the 150-plus New World species we know today, most of which inhabit the Amazon rainforest. Yet exactly how that process unfolded is a bit of a mystery, in large part because of a gap in the monkey fossil record between 13 and 31 million years ago with only a few fragments.

In that gap lies Parvimico. The new fossil dates back 17 to 19 million years, which puts it “smack dab in the time and place when we would have expected diversification to have occurred in the New World monkeys,” Kay said.

The team is currently on another fossil collecting expedition in the Peruvian Amazon that will wrap up in August, concentrating their efforts in remote river sites with 30-million-year-old sediments.

“If we find a primate there, that would really be pay dirt,” Kay said.

Other authors include Jean-Nöel Martinez and Luis Angel Valdivia of the National University of Piura, Lauren Gonzales of the University of South Carolina, Wout Salenbien and Paul Baker of Duke’s Nicholas School of the Environment, Siobhán Cooke of the Johns Hopkins University School of Medicine, and Catherine Rigsby of East Carolina University.

This research was supported by the National Science Foundation (EAR 1338694, DDIG 0726134) and the National Geographic Society (Young Explorers Grant 9920-16 and Waitt Grant W449-16).


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Materials provided by Duke University. Original written by Robin A. Smith. Note: Content may be edited for style and length.

Oldest completely preserved lily discovered

Botanist Dr. Clement Coiffard of the Museum für Naturkunde Berlin discovered the oldest, completely preserved lily in the research collection: Cratolirion bognerianum was found in calcareous sediments of a former freshwater lake in Crato in northeastern Brazil. With an age of about 115 million years, Cratolirion is one of the oldest known monocotyledonous plants. These include orchids, sweet grasses, lilies and lilies of the valley.

Cratolirion is extraordinarily well preserved, with all roots, the flower and even the individual cells are fossilised. With a length of almost 40 centimetres, the specimen is not only extremely huge, but also shows almost all the typical characteristics of monocotyledonous plants, including parallel-veined, narrow leaves with a leaf sheath, a fibrous root system and triple flowers.

However, it was not trivial to examine the fossilised object, as it consisted of iron oxides associated with the stone. In order to see details here, Coiffard collaborated with the HZB physicist Dr. Nikolay Kardjilov, who is an expert in 3D analysis with X-rays and neutrons. At the HZB he also built up a 3D computed x-ray tomography and refined the data analysis in such a way that hardly any disturbing artefacts arise during the investigation of large, flat objects. This made it possible to analyse the details of the inflorescence hidden in the stone. A colour coding in the CT scan makes these details visible: the main axis is marked in turquoise, the supporting leaves in dark green, the pistils in light green and the remains of the actual petals can still be seen in orange.

Many early dicotyledonous flowering plants have already been described from the same sediments of the former freshwater lake in Crato. These include water lilies, aron rods, drought-resistant magnolias and relatives of pepper and laurel. In contrast to other flowering plants of the same age from the USA, Portugal, China and Argentina, the flowering plants of the Crato-Flora are unusually diverse. This could be due to the fact that Lake Crato was in the lower latitudes, but all other fossils of early flowering plants come from the middle latitudes.

From this newly described plant Cratolirion bognerianum and the species of Crato flora mentioned above, it can be deduced that the tropical flowering plants were already very diverse. “It is probable that flowering plants originated in the tropics, but only very few fossils have been described to date,” explains Coiffard. This study thus provides new insights into the role of the tropics in the development of early flowering plants and their rise to global supremacy.


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Bird with unusually long toes found fossilized in amber

Meet the ancient bird that had toes longer than its lower legs. Researchers have discovered a bird foot from 99 million years ago preserved in amber that had a hyper-elongated third toe. The study, published in the journal Current Biology on July 11, suggests that this bird might have used its toes to hook food out of tree trucks. This is the first time such a foot structure has been observed in birds, either extinct or living.

“I was very surprised when I saw the amber,” says first author Lida Xing at China University of Geosciences (Beijing). “It shows that ancient birds were way more diverse than we thought. They had evolved many different features to adapt to their environments.”

To study the Cretaceous period fossil, Xing and his colleagues scanned the amber with micro-CT and created a 3D reconstruction of the foot. They found that the bird’s third toe, measuring 9.8 millimeters, is 41 percent longer than its second toe and 20 percent longer than its tarsometatarsus, which is a bone in the lower legs of birds. The team compared the ratios with those of 20 other extinct birds from the same era and 62 living birds. No bird has a foot that resembles this one.

The researchers named it Elektorornis chenguangi. Elektorornis means “amber bird,” and it belongs to a group of extinct birds called Enantiornithes, the most abundant type of bird known from the Mesozoic era. It is thought that Enantiornithines became extinct during the Cretaceous-Paleogene extinction event about 66 million years ago, along with dinosaurs. They have no living descendants.

Based on the fossil, the team estimates that the Elektorornis was smaller than a sparrow, and it was arboreal, meaning it spent most of its time in trees as opposed to on the ground or in water.

“Elongated toes are something you commonly see in arboreal animals because they need to be able to grip these branches and wrap their toes around them,” says co-author Jingmai O’Connor at the Chinese Academy of Sciences. “But this extreme difference in toe lengths, as far as we know, has never been seen before.”

The amber the foot was found in, measuring 3.5 centimeters long and weighing 5.5 grams, was discovered around 2014 in the Hukawng Valley of Myanmar. During the Mesozoic era, the valley was full of trees that produced resin, a gooey substance that oozes out of the tree bark. Plants and small animals, such as geckos and spiders, often get trapped in the resin and become fossilized with the amber after millions of years. Scientists have discovered many extinct animals, including the oldest known bee and a feathered dinosaur tail, in amber from this valley.

Xing obtained the amber from a local amber trader, who didn’t know what animal this weird foot belonged to.

“Some traders thought it’s a lizard foot, because lizards tend to have long toes,” Xing says. “Although I’ve never seen a bird claw that looks like this before, I know it’s a bird. Like most birds, this foot has four toes, while lizards have five.”

It remains unknown why the amber bird evolved such an unusual feature. The only known animal with disproportionally long digits is the aye-aye. The aye-aye is a lemur that uses its long middle fingers to fish larvae and insects out of tree trunks for food. Therefore, the researchers suggest Elektorornis might have used its toe for the same purpose.

“This is the best guess we have,” O’Connor says. “There is no bird with a similar morphology that could be considered a modern analog for this fossil bird. A lot of ancient birds were probably doing completely different things than living birds. This fossil exposes a different ecological niche that these early birds were experimenting as they evolved.”

Moving forward, the team hopes to extract the proteins and pigments from some feathers exposed on the surface of the amber. Xing says such data could help them better understand the bird’s adaptation to the environment, such as whether it had camouflage plumage.


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