New species of dinosaur, a cousin of Velociraptor, probably glided on four “wings” and hunted early birds

Field Museum

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The new microraptor dinosaur Jian changmaensis (left) attacks the early bird Gansus yumenensis (right) in what is now the Changma Basin of northwestern China approximately 120 million years ago. Credits: illustration by Lewis LaRosa, colorized by Jão Canola.

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Credit: Credits: illustration by Lewis LaRosa, colorized by Jão Canola.

A fossil bed in northwestern China is littered with the remains of hundreds of prehistoric birds—including some whose broken bones were crushed into pellets, similar to those coughed up by modern owls. For years, scientists guessed that a larger predatory animal must have hunted these ancient birds, but they never found direct fossil evidence of this predator. But in a new paper published in the Annals of Carnegie Museum, researchers announced the discovery of a new species of dinosaur from this fossil bed—a cousin of Velociraptor with long feathers on its front and back limbs. Based on the dinosaur’s distinctive arm and shoulder bones, scientists hypothesize that this animal is the missing predator.

“Scientists have found these weird, broken-up clusters of bird bones at this site, and we didn’t know what made them. This new microraptor dinosaur, Jian changmaensis, is our best guess,” says Jingmai O’Connor, the associate curator of fossil reptiles at the Field Museum in Chicago and senior author of the paper describing the new species. “It’s the only dinosaur found at this site that wasn’t a bird, it was a carnivore, and it was much bigger than everything else that we’ve found there.”

Modern birds are the only group of dinosaurs that survived the after-effects of a meteorite hitting the Earth 66 million years ago. But birds and their fellow dinosaurs lived together for tens of millions of years in the Jurassic and Cretaceous periods. One group of dinosaurs, the dromaeosaurs, were close cousins of the bird-dinosaurs. Dromaeosaurs, like birds, were covered in feathers and tended to be relatively small and speedy. The Velociraptors made famous in Jurassic Park are probably the most famous dromaeosaurs (but they would have been smaller and more feathery than they're depicted in the movies).

The new species, Jian changmaensis, belongs to a clade within the dromaeosaur family called microraptors. Microraptors tended to be small; the most well-known species is about the size of a crow. “Jian is one of the biggest microraptor specimens that has ever been found,” says O’Connor. “The piece of its upper arm bone that we have is about 4 inches long, so the entire dinosaur probably had something like a four-foot wingspan, around the size of a barn owl.”

And while scientists only have Jian’s arm, they suspect that Jian, like its fellow microraptors, had long feathers on both its arms and its legs, giving it the appearance of having four “wings” that it used to glide. “Jian and the other microraptors probably weren’t capable of true, powered flight, but they could probably glide like a flying squirrel,” says O’Connor.

The new dinosaur’s name, Jian changmaensis, is a reference to its bird-like appearance and its place of origin. Jian is a winged creature in Chinese mythology, and the fossil was found in the Changma Basin in China’s Gansu province.

“Jian changmaensis reveals that non-avian dinosaurs lived in what is now the Changma Basin, an area famous for its fossil birds,” says Matt Lamanna, corresponding author of the study and  Carnegie Museum of Natural History’s Mary R. Dawson Curator of Vertebrate Paleontology and senior dinosaur researcher. “Our team has recovered more than a hundred bird fossils at Changma, but only this single non-avian dinosaur specimen. Jian provides critical new insight into the biological history of the Changma region and the ecological context of the ancestors of today’s birds.”

“You cannot understand life on the planet today without looking at its origins,” says O’Connor. “Birds are arguably the most successful group of land-dwelling vertebrate animals on Earth today. Learning about early birds and their close non-bird dinosaur relatives gives us a better understanding of what made the group of birds that survived so special.”

This study was contributed to by Ling-Qi Zhou (Gansu Geological Museum), Matthew Lamanna (Carnegie Museum of Natural History), Ashley Poust (University of Nebraska State Museum and University of California Museum of Paleontology), Da-Qing Li (Gansu Agricultural University), Hai-Lu You (Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences), and Jingmai O’Connor (Field Museum).

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Figure 2 from Zhou et al paper, showing the arm bones of the new dinosaur Jian.

Credit

Zhou et al

Journal

Annals of Carnegie Museum

Article Title

FIRST NON-AVIAN THEROPOD (DROMAEOSAURIDAE, MICRORAPTORINAE) FROM THE BIRD-BEARING LOWER CRETACEOUS XIAGOU FORMATION OF THE CHANGMA BASIN, GANSU PROVINCE, NORTHWESTERN CHINA

Article Publication Date

4-Jun-2026

DENTAL FOSSILS NOT DENTAL FLOSS

Dinosaur dental fossils reveal bird-like parental care bonds

Tooth patterns reveal complex nurturing behavior, study says

Ohio State University

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COLUMBUS, Ohio – Baby dinosaurs were likely fed more nutritious food than their adult counterparts, a finding that could offer insights into their social evolution, suggests a new study. 

Paleontologists uncovered this finding by studying wear on the fossilized teeth of Maiasaura peeblesorum, a duck-billed dinosaur species that lived about 75 to 80 million years ago during the Late Cretaceous. First discovered in Montana, these large, herbivorous dinosaurs lived in herds and were thought to have been highly social creatures, especially in contrast to those that may have had different reproductive strategies. 

Extensive fossil findings of preserved Maiasaura nests have since made them a key species for understanding the reproductive behaviors and ecology of many other types of duck-billed dinosaurs. Now, closer analysis of their dental wear patterns has revealed that while juvenile Maiasaura teeth had significantly more crushing wear, adults exhibited more shearing wear, suggesting parents could have been bringing softer, higher-protein food to their children than they themselves ate. 

Today, this behavior is typical of birds whose young are confined to the nest for a time after hatching, said John Hunter, lead author of the study and an associate professor in evolution, ecology and organismal biology at The Ohio State University, meaning that these dinosaurs could have exhibited a level of parental care unusual for most species on Earth at the time.  

“The urge for a bird to feed a youngster is a very old behavior,” said Hunter. “What we’re providing is that evidence for that behavior probably goes much further than the origin of birds, perhaps to the origin of dinosaurs.”

Learning more about which social behaviors may have endured throughout evolutionary history can give scientists a better glimpse into how organisms made a living tens of millions of years ago, as well as help predict traits modern animals might pass on to their descendants. 

The study was recently published in the journal Palaeogeography, Palaeoclimatology, Palaeoecology.

Researchers specifically detail that juvenile Maiasaura likely ate more nutritious low-fiber foods like fruit while their caretakers consumed a greater proportion of tougher, nutritionally poor high-fiber plant parts. In mammals today, the same patterns of shearing wear would likely be present in grazers like horses, antelopes and cows, while low-fiber diet eaters like tapirs would have dental patterns similar to the young dinosaurs. 

In comparing the types of wear on dinosaur teeth, researchers also suggested that shifts in diet may have also performed an important role in early growth and development. In this instance, their results show that the diet of juvenile Maiasaura may have caused them to grow particularly fast in their first year.

The study also considers other interpretations of their results. Instead of consuming completely different fare, dinosaur parents could have been feeding their young partially regurgitated food, yet another behavior now common in birds. Alternatively, juveniles could also have left the nest to forage for themselves, an activity now seen in modern herbivorous lizards.  

While that solution is less likely as juveniles were helpless, and probably dependent on their parents to feed them during the first weeks after hatching, learning more about their remains can widen scientists’ perspectives of what sophisticated biological and social systems dinosaurs may have had, said Hunter. 

“The further back in time you go, the less of a fossil record you have, so paleontologists have to draw from different sources of inspiration from different parts of the living,” he said. “So even among closely related dinosaurs, there is probably still quite a bit to learn about them.”

If possible, future studies could examine other fossils of the very youngest dinosaurs for dental microwear to test other hypotheses regarding dinosaur embryos and hatchlings.

Christine Janis from the University of Bristol and the University of Brown was a co-author. This work was supported by Brown University.

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Contact: John Hunter, Hunter.360@osu.edu

Written by: Tatyana Woodall, Woodall.52@osu.edu

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Journal

Palaeogeography Palaeoclimatology Palaeoecology

DOI

10.1016/j.palaeo.2026.113707 

Method of Research

Case study

Subject of Research

Animals

Article Title

Tooth wear in juvenile and adult hadrosaurs: implications for parental care in Maiasaura☆

Article Publication Date

15-May-2026

 

Researchers show dinos hatched eggs less efficiently than modern birds

Research using dinosaur body model suggests that – unlike modern birds – bird-like dinosaurs may have used the sun’s warmth to help hatch eggs, shedding light on the evolution of avian-style incubation.

Frontiers

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Lateral view of the clutch. The eggs were molded from casting resin. 

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Credit: Chun-Yu Su.

What do we really know about how oviraptors – bird-like but flightless dinosaurs – hatched their eggs? Did they use environmental heat, like crocodiles, or body heat from an adult, like birds? In a new Frontiers in Ecology and Evolution study, researchers in Taiwan examined the brooding behavior and hatching patterns of oviraptors. They also modelled heat transfer simulations of oviraptor clutches and compared hatching efficiency to modern birds. To do so, they experimented with a life-sized oviraptor incubator and eggs.

“We show the difference in oviraptor hatching patterns was induced by the relative position of the incubating adult to the eggs,” said senior author Dr Tzu-Ruei Yang, an associate curator of vertebrate paleontology at Taiwan’s National Museum of Natural Science.

“Moreover, we obtained an estimate of the incubation efficiency of oviraptors, which is much lower than that of modern birds,” added first author Chun-Yu Su, who attended Washington High School in Taichung when the research was conducted.

Building a dinosaur

The reconstructed oviraptor Heyuannia huangi lived between 70 and 66 million years ago in what today is China. Estimated to be around 1.5 meters long and weighing around 20kg, it built semi-open nests made up of several rings of eggs.

The incubating oviraptor’s trunk was made from polystyrene foam and wood for the skeletal frame and cotton, bubble paper, and cloth for the soft tissue. Eggs were molded from casting resin. In the two clutches used in the experiments, eggs were arranged in double-rings based on real oviraptor clutches.

“Part of the difficulty lies in reconstructing oviraptor incubation realistically,” said Su. “For example, their eggs are unlike those of any living species, so we invented the resin eggs to approximate real oviraptor eggs as best as we could.”

When the team ran experiments to find out if clutch attendance of a brooding adult or different environmental circumstances may have impacted hatching patterns, they found that in colder temperatures, where a brooding adult attended the clutch, the eggs’ temperatures in the outer ring differed by up to 6°C, which could have resulted in asynchronous hatching, a pattern where eggs in the same nest hatch at different times. In warmer conditions, the difference in egg temperatures in the outer ring was just 0.6°C, suggesting that oviraptors living in warmer conditions may have exhibited a different pattern of asynchronous hatching because they could use the sun as an additional, powerful heat source.

“It’s unlikely that large dinosaurs sat atop their clutches. Supposedly they used the heat of the sun or soil to hatch their eggs, like turtles. Since oviraptor clutches are open to the air, heat from the sun likely mattered much more than heat from the soil,” Yang explained.

Better hatchers?

The team also investigated how oviraptor incubation efficiency compares to that of modern birds. Most birds use thermoregulatory contact incubation (TCI), where adults sit directly on the eggs to transfer heat. TCI requires three prerequisites – the adult bird must be in contact with every egg, be the main heat source, and maintain all eggs within a constrained temperature range – which oviraptors didn’t fulfil. For example, their egg arrangement prevented the adult from making full contact with all eggs in the clutch.

“Oviraptors may not have been able to conduct TCI as modern birds do,” said Su. Instead, these dinosaurs and the sun may have been co-incubators – a less efficient incubation behavior than that displayed by modern birds. Yet, the combination of adult incubation and an ambient heat source – perhaps a behavioral adaptation associated with the evolution from buried to semi-open nests – isn’t necessarily worse.

“Modern birds aren’t ‘better’ at hatching eggs. Instead, birds living today and oviraptors have a very different way of incubation or, more specifically, brooding,” Yang pointed out. “Nothing is better or worse. It just depends on the environment.”

The team pointed out that their findings are specific to the reconstructed nest and are limited by the fact that today’s climate does not resemble the Late Cretaceous climate, which may have impacted the results. Oviraptors also exhibited a longer incubation period than modern birds.

Yet, the study advances our understanding of oviraptor brooding strategies through innovative approaches. It represents an important bridge between physics-based simulations and paleontological interpretations, potentially enabling paleontologists to investigate topics for which approaches were limited until now.  

“It also truly is an encouragement for all students, especially in Taiwan,” concluded Yang. “There are no dinosaur fossils in Taiwan but that does not mean that we cannot do dinosaur studies.”

Lateral view of the clutch with the incubator on top

Photograph of the generalized clutch after Experiment III.

Dorsal view of the incubator.

Credit

Chun-Yu Su.

The arrangement of thermometers in the incubation experiments. Thermometers 1 (with thicker outlines) were used in Experiment II. Thermometers 2 (with lighter outlines) were the additional thermometers used in Experiment III. The schematic presents a lateral view of the clutch and the incubator.

Credit

Su et al.,2026.

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Journal

Frontiers in Ecology and Evolution

DOI

10.3389/fevo.2026.1351288 

Method of Research

Experimental study

Subject of Research

Not applicable

Article Title

Heat transfer in a realistic clutch reveals a lower efficiency in incubation of oviraptorid dinosaurs than of modern birds

Article Publication Date

17-Mar-2026

 

Tiny’ dinosaur, big impact: 90-million-year-old fossil rewrites history

New study says Alnashetri originated when the continents were still connected as the supercontinent Pangaea

University of Minnesota

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A new study of fossils from a bird-like dinosaur, called Alnashetri, provides new insight into how its lineage evolved, shrank and spread across the ancient world.

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Credit: Gabriel Díaz Yantén, Universidad Nacional de Río Negro.

MINNEAPOLIS / ST. PAUL (02/25/2026) — A team co-led by University of Minnesota Twin Cities researcher Peter Makovicky and Argentinean colleague Sebastian Apesteguía has identified a 90-million-year-old fossil that provides the “missing link” for a mysterious group of prehistoric animals. 

The study, published in the peer-review journal Nature, details the discovery of a complete skeleton of Alnashetri cerropoliciensis. Alnashetri belongs to a group of bird-like dinosaurs, known as alvarezsaurs, that are famous for their tiny teeth and stubby arms ending in a single large thumb claw. For decades, they have remained a mystery because most of the well-preserved fossils were found in Asia, while records from South America were fragmented and difficult to interpret.

In 2014, the almost complete fossil of Alnashetri was discovered in the northern part of Patagonia, Argentina, at a site that is world-renowned for its exquisite Cretaceous fossils. The species was originally named a few years prior based on fragmentary remains, but this newer, more complete specimen allowed the team to finally map the group's strange anatomy. The team spent the last decade carefully preparing and piecing together the fossils to avoid damaging the small bones.

“Going from fragmentary skeletons that are hard to interpret, to having a near complete and articulated animal is like finding a paleontological Rosetta Stone,” said Peter Makovicky, lead author on the paper and a professor in the University of Minnesota Department of Earth and Environmental Sciences. “We now have a reference point that allows us to accurately identify more scrappy finds and map out evolutionary transitions in anatomy and body size.”

The discovery of this nearly complete skeleton opens up a new understanding of how its lineage evolved, shrank and spread across the ancient world.

• Unlike its later relatives, Alnashetri had long arms and larger teeth. This proves that some alvarezsaurs evolved to be tiny long before they developed these specialized features thought to be adaptations for an "ant-eating" diet.

• Microscopic analysis of the bones confirmed the animal was indeed an adult of at least four years old. These animals are not just among the tiniest non-avian dinosaurs, but they never get any bigger—the largest species are the size of an average human, very small for dinosaurs, and Alnashetri itself weighed less than 2 lbs making it one of the smallest dinosaurs known from South America.

• By identifying previously found alvarezsaurs fossils in museum collections from North America and Europe, the team proved these animals originated much earlier than expected when the continents were still connected as the supercontinent Pangaea. Their distribution was caused by the breakup of the earth's landmasses, not unlikely treks across oceans.

The well-preserved fossil was recovered from the La Buitrera fossil area, a site that has yielded other scientifically critical animals, including primitive snakes and tiny saber-toothed mammals.

“After more than 20 years of work, the La Buitrera fossil area has given us a unique insight into small dinosaurs and other vertebrates like no other site in South America," said Apesteguía, a researcher at Universidad Maimónides in Buenos Aires, Argentina. 

Their work is far from over, as the scientists continue to discover and study fossils from the same area where they discovered Alnashetri. “We have already found the next chapter of the alvarezsaurid story there, and it is in the lab being prepared right now,” added Makovicky.

In addition to Makovicky and Apesteguía, the international team included Jonathan S. Mitchell from Coe College in Iowa; Jorge G. Meso and Ignacio Cerda from Instituto de Investigación, Universidad Nacional de Río Negro and Museo Provincial; and Federico A. Gianechini from Instituto Multidisciplinario de Investigaciones Biológicas de San Luis.

The research was supported by the National Scientific and Technical Research Council (CONICET), The Field Museum, National Geographic, University of Minnesota, United States National Science Foundation and the Fulbright U.S. Scholar program.

Read the full paper entitled, “Argentine fossil rewrites evolutionary history of a baffling dinosaur clade,” on the Nature website

Alnashetri was rapidly covered by an advancing sand dune that preserved it almost intact for 90 million years.

Credit

Peter Makovicky, University of Minnesota

University of Minnesota Professor Peter Makovicky uncovers fossil bones at the La Buitrera fossil area.

Credit

Minyoung Son, University of Minnesota

Alnashetri animation [VIDEO] |

Alnashetri belongs to a group of bird-like dinosaurs, known as alvarezsaurs, that are famous for their tiny teeth and stubby arms ending in a single large thumb claw.

Credit

Universidad Nacional de Río Negro and University of Minneso

Journal

Nature

DOI

10.1038/s41586-026-10194-3 

Article Title

Argentine fossil rewrites evolutionary history of a baffling dinosaur clade

Article Publication Date

25-Feb-2026