Tag Archives: Lineage

New Research Uncovers Nanotyrannus as a Unique Dinosaur Lineage

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Paleontologists investigated a remarkably preserved and nearly mature Tyrannosaurus rex skeleton found in the Hell Creek Formation of Montana. Their findings suggest that this specimen exhibits traits similar to the holotype of Nanotyrannus and confirm that this lineage is distinct from tyrannosaurus.

A pack of Nanotyrannus daringly attacks a young tyrannosaurus rex. Image credit: Anthony Hutchings.

“This fossil turns decades of research on its head,” stated Dr. Lindsay Zanno, a researcher at North Carolina State University and the North Carolina Museum of Natural Sciences.

The researchers utilized tree ring data, spinal fixation, and developmental anatomy to show that the new specimen reached physical maturity at around 20 years.

Skeletal characteristics like larger forelimbs, more teeth, fewer caudal vertebrae, and distinctive skull neural patterns are established early in development and are biologically incompatible with tyrannosaurus rex.

“For Nanotyrannus to develop into a tyrannosaurus rex would contradict everything we know about vertebrate growth. That’s not just unlikely; it’s impossible,” remarked Dr. James Napoli, a researcher at Stony Brook University.

For years, paleontologists have incorrectly modeled tyrannosaurus growth and behavior using Nanotyrannus fossils.

This new evidence indicates that those studies were based on two entirely different species, suggesting that multiple tyrannosaurus species coexisted in the same ecosystem during the last million years before the asteroid impact.

As part of their study, Dr. Zanno and Dr. Napoli analyzed over 200 Tyrannosaurus fossils.

They found one skeleton, previously thought to represent a juvenile tyrannosaurus rex, that differed from the documented species Nanotyrannus lansensis, which is part of the renowned dueling dinosaur fossil.

The authors concluded that this specimen is a new species of Nanotyrannus, named Nanotyrannus letaeus.

The confirmation of Nanotyrannus implies that predator diversity during the final million years of the Cretaceous was far greater than previously understood, indicating that other small dinosaur species may also have been misidentified.

“This discovery provides a more complex and competitive view of the last days of the dinosaurs,” Dr. Zanno mentioned.

“With its massive physique, powerful bite, and stereoscopic vision, tyrannosaurus rex was indeed a fierce predator, but it did not dominate its environment without competition.”

“Darting together were Nanotyrannus — a slimmer, faster, more agile hunter.”

These findings were published in today’s edition of Nature.

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LE Zanno and JG Napoli. Nanotyrannus and tyrannosaurus coexisted at the end of the Cretaceous period. Nature published online October 30, 2025. doi: 10.1038/s41586-025-09801-6

Source: www.sci.news

Tiny Fossils Uncover New Lineage of New Zealand Songbirds

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Paleontologists have unearthed a 2.9-centimeter fossil foot bone believed to belong to a bowerbird at the Miocene site of St Bassans in Aotearoa, New Zealand.

Recreating the life of the St. Bassin’s bowerbird (Aeviperditus gracilis). Image credit: Sasha Votyakova / Te Papa / CC BY 4.0.

The newly identified species existed in New Zealand during the Miocene epoch, approximately 19 to 14 million years ago, well away from its close relatives in Australia and New Guinea.

“This finding offers significant and unique insight into the biological history of Aotearoa’s avian life,” stated Dr. Nick Lawrence, director of the Otago Institute of Paleogenetics.

“For many around the globe, bowerbirds gained fame from Sir David Attenborough’s documentaries featuring their intricate courtship rituals. Males construct arched structures called bowers, adorned with colorful items such as sticks and occasionally fruit, leaves, or even plastic, to attract a mate.”

Known as Aeviperditus gracilis or St. Bassin’s bowerbird, this new bird species was considerably smaller than its modern counterparts.

“It weighs only 33g, much lighter than both existing and extinct bowerbird species, which typically range from 96 to 265g,” Dr. Lawrence explained.

“Its leg bones closely resemble those of Avenue Bower builders, including the brightly colored Flame Bowerbird and Satin Bowerbird.”

“If this bird is indeed a relative of bowerbirds, it could represent an entirely new lineage of songbirds for Aotearoa,” suggested Dr. Elizabeth Steele, a researcher at the University of Cambridge.

“This is particularly crucial given our limited understanding of the region’s ancient songbird fossil record.”

“St Bathan’s Bowerbird signifies the latest lineage of songbirds with a long evolutionary history in Aotearoa, with the earliest representatives of groups like the Uia, Koukako, Tieke, Piopio, and Mohua found here.”

“All these species likely evolved rapidly and dispersed from Australia to New Zealand.”

“Like many of St. Bathans’ unique species, this bird has no surviving descendants in Aotearoa.”

“The bowerbird seems to have been particularly vulnerable to the cooling temperatures preceding the Ice Age and the resulting shifts in forest composition and distribution, contributing to its extinction,” Dr. Lawrence noted.

An article detailing the discovery of Aeviperditus gracilis was published on October 7, 2025, in Historical Biology, International Journal of Paleontology.

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Elizabeth M. Steele et al. Possible early Miocene bowerbirds of New Zealand. Historical Biology, published online October 7, 2025. doi: 10.1080/08912963.2025.2568099

Source: www.sci.news

Scientists release updated primate evolutionary lineage

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Primates, consisting of apes, monkeys, tarsiers, and lemurs, are among the most charismatic and well-studied animals on Earth.

Phylogeny of 455 primates synthesized using Chrono-STA. The roots of the phylogeny were discovered 71.3 million years ago. The crown of Strepsirrhini is 57 million years old, and the crown of Haplorrhini is 68.5 million years old. The crown of the eyelid is 42.2 million years old. Image credit: Craig others., doi: 10.3389/fbinf.2024.1495417.

Primate mammals consist of 172 species of Old World apes and monkeys (Cataluni), 146 species of New World monkeys (Platyria), and 144 species of lemurs, lorises, and galagos (Strepsilini).

Primates exhibit some of the most remarkable behaviors observed in nature. Chimpanzees use specially chosen sticks to “fish” for termites inside hollow logs, while orangutans use leaves as gloves to handle the prickly durian fruit.

Although they are some of the most intensely studied species on Earth, there is no comprehensive molecular phylogenetic hypothesis about the evolutionary history of primates that summarizes the patterns and timing of relationships among all primates. plug.

Such phylogenetic trees use molecular sequence data to tell us both when each species or group of species first appeared and which other groups on the tree are their closest relatives. Masu.

The largest timed molecular phylogenetic tree, called the “Time Tree,” includes just over 200 primate species to date, but the largest synthetic time tree, based on more than 4,000 published studies, , containing only twice that number, and about one-fifth of the primates remaining. The tree of life is unresolved.

“The value of a timed evolutionary tree that includes all species of a particular lineage cannot be underestimated,” said lead author Dr. Jack Craig and colleagues at Temple University.

“These trees are inherently fascinating because they capture the evolutionary history that has given us our current biodiversity, but they also form an essential foundation for many types of future research. I will.”

“For example, taxonomic and systematic efforts to catalog species rely on them to identify new lineages.”

“The study of the rate of evolution and its possible correlations, such as climate and geological changes, is fundamentally tied to its underlying phylogeny.”

“Disciplines such as biogeography, phylogeography, and historical ecology, which use time trees to investigate spatial and ecological patterns, would not be possible without phylogeny.”

“And as we watch global biodiversity being lost in ongoing extinction events, phylogenetics can help identify conservation priorities and help save species. It is an essential tool in assessing the impact of our efforts.”

In the new study, the authors were able to construct a time tree of 455 primates, incorporating all species for which molecular data are available.
This phylogenetic tree is the most complete description of the evolutionary relationships among primates to date.

“This effort proves that while the evolutionary history of even some of the most charismatic species on Earth is incompletely understood, we have the tools to fill many of the knowledge gaps. “We did so,” the researchers said.

“We believe our research protocol will be an accessible and ultimately extremely valuable tool in the effort to understand evolution.”

“We have found that complete time trees are a fundamental resource in many fields and can often be constructed from existing data.”

“Furthermore, such a complete time tree allows us to test hypotheses that would otherwise not be possible.”

“For example, our study shows that the number of species in different primate clades is better explained by unique rates of speciation, with some primate lineages generating new species much faster than others. Or whether the best explanation is simply time: all lineages produce new species at about the same rate, and older lineages produce more species over time.''

“What we discovered is that the major groups of primates actually all share relatively similar speciation rates, and therefore their age is a better predictor of species richness. That's what it means.

“This analysis becomes very problematic when a time tree is missing many species or dates, so it serves as a perfect example of the usefulness of large, complete time trees.”

of the team result appear in the diary Frontiers of bioinformatics.

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Jack M. Craig others. 2024. Completed primate molecular time tree. Frontiers of bioinformatics 4;doi: 10.3389/fbinf.2024.1495417

Source: www.sci.news

New study reveals that one human lineage experienced an increase in brain size

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A recent study conducted by researchers at the University of Reading and the University of Durham has revealed that the increase in relative brain size, known as encephalization, during the seven million years of human evolution was a result of incremental changes within individual species.

Modern humans, Neanderthals, and other recent relatives on the human family tree evolved large brains much more rapidly than earlier species. Image credit: SINC / Jose Antonio Peñas.

“One of the most striking evolutionary changes in human evolution, closely linked to the unique cognitive and behavioral characteristics of humans, is the increase in brain size,” explained lead author Thomas Puschel and his colleagues.

“The question of encephalization in human evolution has been a topic of debate, with various studies comparing the brain capacities of different hominin species and exploring adaptive mechanisms that might have influenced differences in brain size among hominins. Our research proposes

“Some argue for a gradual growth pattern over time, while others suggest a pattern of rapid increases followed by periods of stagnation.”

“Certain studies support a combination of both models, while others claim that they are indistinguishable.”

In their recent study, the authors compiled the largest dataset of ancient human fossils spanning seven million years and utilized advanced computational and statistical methods to identify gaps in the fossil record.

These innovative approaches have provided the most comprehensive understanding to date of the evolution of brain size over time.

“This study has completely altered our perception of how the human brain evolved,” noted study co-author Professor Chris Venditti.

“Previously, it was believed that brain size varied significantly between species, like upgrading to newer computer models.”

“However, our study reveals a pattern of steady, incremental ‘software updates’ occurring within each species over millions of years.”

This study challenges the traditional notion that certain species, such as Neanderthals, remained unchanged and were unable to adapt, suggesting instead that the increase in brain size was a gradual and continuous driving force in evolution. It underscores the significance of changes.

“Major evolutionary shifts do not always require dramatic events,” Pushel stated.

“They can result from making small incremental improvements over time, akin to the learning and adaptation processes observed today.”

The researchers also identified a notable pattern: larger-bodied species tend to have larger brains, but the variation observed within individual species does not consistently correlate with body size.

Hence, the evolution of brain size over long evolutionary timescales spanning millions of years has been influenced by factors distinct from those observed within individual species, underscoring the complexities of evolutionary pressures on brain size. It’s remarkable.

“The reasons behind the evolution of large brains in humans are a key aspect of human evolution,” added study co-author Dr. Joanna Baker.

“Through analyzing the brain and body sizes of various species over millions of years, we have demonstrated that the characteristic large brains of humans primarily emerged through gradual changes within individual species. This became evident.”of study On November 26, 2024, Proceedings of the National Academy of Sciences.

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Thomas A. Puschel others. 2024. The increase in human brain size was revealed by intraspecific encephalization. PNAS 121 (49): e2409542121;doi: 10.1073/pnas.2409542121

Source: www.sci.news

Newly Discovered Fossils Shed Light on Enigmatic Human Lineage in the Levant

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Orthographic view of the static skull, mandible, and parietal bones.Credit: Tel Aviv University

Nesher Ramla homoan ancient hominin group discovered in Israel reveals a complex admixture of Eurasian and African hominins 140,000 years ago, changing perceptions of the origins of Neanderthals.

Researchers have discovered a previously unknown archaic hominin group they named Nesha Ramla. homo” at a recently excavated site in Israel. This group, dating from about 140,000 to 120,000 years ago, is thought to be the last survivor of the Middle Pleistocene. homo. They exhibit a unique blend of Neanderthal and ancient human characteristics and technology.

Neanderthals are thought to have originated and flourished in continental Europe long before modern humans arrived. However, recent evidence suggests a genetic contribution from as yet unknown non-European populations and points to a long and dynamic history of interactions between Eurasian and African hominin populations.

Human interaction in Eurasia and Africa

Here, Israel Hershkovitz, Yossi Zeidner and colleagues present fossil, artifact, and radiometric evidence from the Levantine region of the Middle East that illustrates this complexity. According to Hershkovitz et al., the newly discovered Nesher Ramla homo They exhibit anatomical features that are older than their contemporaneous Eurasian Neanderthals and modern humans, who also lived in the Levant. This discovery indicates that this archaic lineage may represent one of the last surviving populations of the Middle Pleistocene. homo in southwest Asia, Africa, and Europe.

Archaeological context and cultural interaction

In joint research, Zaidner other. We provide archaeological context for the new fossils and report on their associated radiometric dates, artifact assemblages, and the behavioral and environmental insights they provide. Researchers found that Nesher Ramla homo Familiar with technology that was previously known only to a select few homo sapiens And Neanderthals. Taken together, these findings provide archaeological support for close cultural interactions and genetic admixture between different human lineages before 120,000 years ago. This may help explain the different expressions of teeth and skeletal features in later Levantine fossils.

“Interpretation of Nesher Ramla fossils and stone tools will have mixed reactions among paleoanthropologists. Nevertheless, the age of Nesher Ramla materials, the discordant morphological and archaeological similarities , and the site’s location at the crossroads of Africa and Eurasia make this a major discovery,” writes Marta Lahr in an accompanying Perspective.

For more information about this research, see Types of prehistoric humans previously unknown to science.

References:

“Middle Pleistocene Homo from Nesher Ramla, Israel” Israel Hershkovitz, Hilla May, Rachel Salig, Ariel Pokhodzhaev, Dominique Grimaud Hervé, Emiliano Bruner, Cinzia Fornai, Rolf Quam, Juan. Written by Luis Arzuaga, Victoria A. Crenn, and Maria Martinon Torres, José María Bermudez de Castro, Laura Martin Frances, Vivian Soulon, Lou Albesado Ball, Amelie Viale, and Tim Schuler , Giorgio Manzi, Antonio Profico, Fabio Di Vincenzo, Gerhard W. Weber, Yossi Seidner, June 25, 2021, science.
DOI: 10.1126/science.abh3169

“Behavior and culture of Homo during the Middle Pleistocene, 140,000 to 120,000 years ago, and interaction with Homo sapiens” Yossi Seidner, Laura Senty, Marion Prevost, Norbert Mercier, Christophe Farguerre, Gilles Guerin, Hélène Valadas, Mairis Richard, Asmodee Ghaly, Christophe Pécherin, Olivier Tombre, Edwidge Pons-Branch, Naomi Porat, Ruth Shahak Gross, David E. Friesem, Reuven Yeshurun, Zohar Turdjman Yaffe, Amos Frumkin, Gadi Herzlinger, Ravid Eckstein, Maayan Shemar, Oz Valoner, Rachel Salig, Hila May, Israel Hershkovitz, June 25, 2021, science.
DOI: 10.1126/science.abh3020

Source: scitechdaily.com