Tag Archives: lizard

New Jurassic Lizard Species Exhibits Features of Both Snakes and Geckos

Posted on by
Reply

Breugnathair elgolensis – This species, part of the Hook-tooth group, thrived in the central Jurassic period around 167 million years ago, displaying a unique blend of anatomical features not usually observed in its raw group. Its head-to-body proportions, along with dental and jaw characteristics, reveal serpent-like traits, with the original extermination group linked to Jeccos.

Reconstruction of the life of Breugnathair elgolensis. Image credit: Brennan Stokkermans/National Museums Scotland.

Breugnathair elgolensis is recognized as one of the earliest relatively complete fossil lizards yet discovered.

These ancient reptiles possessed serpent-like jaws and curved teeth reminiscent of modern pythons, all while exhibiting short bodies akin to well-formed lizards.

With a length of approximately 41 cm (16 inches) from head to tail, it ranks among the largest lizards in its ecosystem and may have preyed on smaller lizards, juvenile dinosaurs, early mammals, and various vertebrates.

Dr. Roger Benson, a curator in the Department of Paleontology at the American Museum of Natural History, remarked:

“Breugnathair elgolensis features snake-like traits in its teeth and jaw, yet in many aspects, it appears surprisingly primitive.”

“This suggests that the evolutionary predecessors of snakes might have been vastly different than we anticipated. Alternatively, it may indicate that predatory behaviors similar to those of snakes developed independently in archaic, extinct groups.”

Paleontologists place Breugnathair elgolensis within a new family of reptiles (encompassing lizards and snakes) named Parviraptoridae, a group that may hold significant implications for snake origins.

“Previous studies had identified bones with snake-like teeth found alongside those exhibiting gecko-like traits,” they noted.

“However, their striking differences led some researchers to believe they belonged to two distinct species.”

“Our research on Breugnathair elgolensis challenges these earlier conclusions, demonstrating that both snake-like and gecko-like characteristics can coexist within a single species.”

The fossil remains of Breugnathair elgolensis were unearthed in 2016 by Stig Walsh of Scotland’s National Museum on the Isle of Skye.

“The Jurassic fossil sediments on the Isle of Skye are vital for understanding the early evolution of numerous living groups, including lizards, which started to diversify during this period.”

“I initially described Parviraptorids around three decades ago based on much more fragmented specimens, making this feel like discovering the top of a jigsaw puzzle years after being stumped by the original picture with a handful of pieces.”

“The array of primitive and advanced features indicated in this new specimen reinforces the notion that evolutionary pathways can be unpredictable.”

A paper discussing the discoveries related to Breugnathair elgolensis was published today in the journal Nature.

____

RBJ Benson et al. Mosaic anatomy in early fossil reptiles. Nature Published online on October 1, 2025. doi:10.1038/s41586-025-09566-y

Source: www.sci.news

The Enigmatic Lizard: Surviving the Chicxulub Asteroid Impact

Posted on by
Reply

Yellow spotted tropical night lizard (Lepidophyma flavimaculatum)

Dante Fenolio/Science Photo Library

A unique and elusive group of lizards remains today, recognized as the only terrestrial vertebrates to withstand the catastrophic Chicxulub asteroid impact, which likely resulted in the extinction of non-avian dinosaurs.

The Xantusiid Night lizard is known as an ancient lineage, surviving for tens of millions of years. However, Chase Brownstein from Yale University and his team proposed that this lineage might have originated earlier than previously estimated.

The end of the Cretaceous period was marked by a colossal asteroid strike near the Yucatán Peninsula in Mexico, creating craters wider than 150 kilometers and leading to the extinction of most animal and plant species globally.

Today, the night lizard—despite its name, not actually nocturnal—continues to inhabit Cuba, Central America, and the southwest region of the United States.

Brownstein and his researchers utilized previously published DNA sequencing data from Xantusiids to construct evolutionary trees for these groups. They integrated findings from skeletal anatomy of current species and fossil records, allowing them to estimate the lineage’s age and the quantity of offspring produced by the ancestral night lizard.

The team identified a shared ancestor that lived deep within the Cretaceous period, dating back over 93 million years, likely producing only one or two clutches of offspring.

“It’s highly probable that these ancient populations were situated close to the impact site, much like their modern counterparts,” remarks Brownstein. “It’s as though the distribution of Xantusiid lizards encircles the impact zones.”

According to fossil records, Brownstein argues that it is improbable for ancient night lizards to have simply returned to the affected areas later.

“Our reconstructions suggest that the common ancestors of living species most likely originated in North America, as the fossil evidence of Xantusiids is relatively continuous on both sides of the boundary layer,” he adds.

Numerous night lizard species inhabit rock crevices and possess a slow metabolism akin to other survivors of mass extinction, like turtles and crocodiles. “This likely enabled them to endure the aftermath of the impact,” states Brownstein.

Nathan Law from the University of Sydney expresses amazement at their survival. “These lizards resided near the asteroid’s impact site; despite the asteroid’s devastating effects within hundreds of kilometers, they managed to survive.”

Remarkably, they achieved this despite lacking many common characteristics typically associated with mass extinction survivors. “Species that endure these extinction events tend to be small, reproduce rapidly, and have extensive geographical ranges,” explains Law. “Conversely, these lizards generally have slower reproduction rates and appear to cover a minimal range.”

topic:

Source: www.newscientist.com

Debunking the Myth of the “Lizard Brain”: Neuroscience and the Truth about Mental Falsehoods

Posted on by
Reply

It’s been said that in times of intense stress or sudden anger, a primitive part of our brain takes control. This irrational aspect of ourselves doesn’t stem from our highly evolved human faculties, but rather from the remnants of our reptilian ancestors that have persisted in our brains despite the process of evolution. Some call it the “lizard brain.”

The lizard brain theory was formulated by neuroscientists in the 1960s, particularly by Paul McLean. As he studied the brains of humans and other animals to explore the origins of negative emotions, he found common behaviors between reptiles and mammals related to survival instincts like establishing routines and defending territory, as well as unique mammalian behaviors.

Through his research and advancements in neuroscience allowing for the comparison of brain structures, MacLean proposed that the human brain evolved from a reptilian brain with ancient lizard characteristics still preserved. He identified three distinct brains within the human brain, which he called the “brain trinity”: the oldest reptilian brain, the paleomammal complex or limbic system, and the new structures that emerged with higher primate evolution.

Paul MacLean's 'Trinity Brain' model now widely discredited by scientists – Photo credit: Getty

Despite the popularity of the triune brain theory, recent studies have challenged the notion of the lizard brain. Neuroanatomists have pointed out that the brain is not structured like an onion with successive layers resembling different species’ brains, as the Trinity theory suggests.

For instance, while the amygdala within the limbic system is more developed in primates than in rats, indicating a more complex evolutionary trajectory, the concept of progress in evolution suggests that older animals are more primitive and newer ones more sophisticated. Evolution is not just about adding new features while leaving the old ones unchanged.

Explore our fascinating collection of fun facts and delve into more intriguing scientific topics.

Learn more:

Source: www.sciencefocus.com

47 million years ago, the world’s largest earthworm lizard roamed Earth

Posted on by
Reply

Paleontologists have described a new genus and species of the trogonophid Amphisbaenian (worm lizard) from fossil specimens discovered in Tunisia.

rebuilding the life of Terrastiodontosaurus Marcelo Sanchesi Ready to prey on large snails of the Brimulidae family. Image credit: Jaime Chirinos.

Terrastiodontosaurus Marcelo Sanchesi They lived in what is now Africa during the Eocene epoch, about 47 million years ago.

The new species belongs to Trogonophidae, a small family of limbless carnivorous lizard-like reptiles belonging to the clade Amphisbaenia.

“Amphibians are a group of charismatic fossil squamates with bizarre morphological features and extreme anatomical variations,” said lead author Dr. Georgios Georgalis of the Institute of Animal Systemology and Evolution, Polish Academy of Sciences and his colleagues. said a colleague.

“In particular, its unique skeletal structure has fascinated and puzzled researchers since the 19th century.”

“Before the advent and widespread acceptance of phylogenetics, amphibians were considered to be the third major group of squamates, along with Serpenta and the paraphyletic 'Lacerthilla'.”

“However, recent phylogenetic analyzes place them as a sister group to lizards in the family Caricidae, and this topology is supported by both molecular evidence and a combination of morphological and molecular evidence. The name Lacertibaenia has also been proposed for the clade Amphisbaenia + Lacertidae.

“Amphibians have a relatively rich fossil record spanning the Cenozoic era in Europe and North America, in addition to several Neogene and Quaternary occurrences from South America and some from Africa. Paleogene, Neogene, and Quaternary productions, very few Neogene productions from the Arabian Peninsula, and very few Neogene occurrences from southwest Asia. is. ”

“Trogonophidae is a fairly distinctive group of amphibians that is today distributed across northern and north-central Africa (including Socotra Island in Yemen) and the Middle East,” the researchers added.

“Currently, four extant genera are recognized. Agamodon, Diplometopon, Pachykaramasu, and the type genus, Trogonophis”

The most distinguishing feature of trogonophids is their hooked teeth, a feature found only among squamates in the otherwise Iguanian group Chronophytes. ”

“Trogonophids have other unique features among amphibians, including locomotion and burrowing patterns, shoulder girdle or hemipenes morphology, chromosomes, spinal arrangement, lack of caudal autodissection, and triangular cross-section. It also has features.

some specimens Terrastiodontosaurus Marcelo Sanchesi It was discovered in a place where fossils of Jebel Chanbi Nature Park In Tunisia.

“Jebel Chambi National Park is located in the Kasserine region of central-western Tunisia,” the paleontologists said.

“Material for this study was obtained from a fossiliferous site (Chambi locus 1) consisting of fluvial-lacustrine deposits located at the base of the Chambi continental sequence.”

“These habitats support fish, amphibians, turtles, crocodiles, squamates, birds, and mammals such as bats, primates, euphorians, hyaenodonts, hyracoids, elephant shrews, marsupials, and mammals. It produces a diverse population of aquatic and terrestrial vertebrates, including rodents and sirenians.

Terrastiodontosaurus Marcelo Sanchesi At over 90 centimeters (35 inches) long, it was the largest amphibian ever known.

“Among the extant amphibian fliers, Amphisbaena Alba is the largest species, reaching a maximum total length of 81 centimeters (32 inches) and a skull length of more than 3.1 centimeters (1.2 inches), the researchers said.

Virtually all modern amphibians are burrowing animals and rarely appear on the surface outside of underground environments.

Nevertheless, certain features Terrastiodontosaurus Marcelo Sanchesi They seem to contradict this natural history pattern and instead suggest that ancient species likely lived on the surface of the earth.

This is further supported by the extreme size. Terrastiodontosaurus Marcelo Sanchesi which makes underground habits less likely to occur.

“Terrastiodontosaurus Marcelo Sanchesi “This is a significant contribution to the fossil record of the hitherto little-known African Amphisbaenia, making it only the fifth species to be named extinct on the African continent,” the scientists concluded. .

“Furthermore, the new material from Chambi further adds to the extremely poor fossil record of the Trogonophidae.”

Regarding new species, paper this week, Zoological journal of the Linnean Society.

_____

Georgios L. Georgalis others. 2024. The world's largest earthworm lizard: a new giant trogonophid (Squamata: Amphisbaenia) with extreme dental adaptations from the Eocene of Chambi, Tunisia. Zoological journal of the Linnean Society 202 (3): zlae133;doi: 10.1093/zoolinnean/zlae133

Source: www.sci.news

Could the massive fish lizard be the largest marine reptile ever found, surpassing the megalodon in size?

Posted on by
Reply

Forget about megalodons being scary, there’s a new prehistoric creature in town with jaws that may rival Meg’s in power, making it the largest marine reptile ever identified on Earth.

The giant jawbone of this beast measures over 2 meters (6.6 feet), allowing for a bite force strong enough to crush bones. In comparison, the jawbone of a megalodon, which was about the same size, measured only 0.5 meters (1.6 feet).

Experts believe that this massive new ichthyosaur species was a staggering 25 meters (82 feet) long, similar in size to a modern blue whale. (Megalodon was about 15-20 meters, or 65 feet in length).

The fossilized remains of this creature were found on the Somerset coast.

The research team named this new species Ichthyotitan severnensis, meaning “Giant Fish Lizard of the Severn.” These bones date back to around 202 million years ago, towards the end of the Triassic period, just before the dinosaur extinction event.

The first jawbone of this mysterious species was discovered in 2016, with this recent find confirming its existence.

Dr. Dean Lomax, a paleontologist at the University of Manchester, expressed excitement about the discovery, hoping that more complete specimens may be found in the future.

Lomax and his team compared the two jawbones and found shared unique features, indicating they were from the same geological period.

Ruby Reynolds, an 11-year-old girl, discovered a new salangular on the beach in 2020, leading to further discoveries by her and her team, including the final piece of the jawbone in 2022.

Now 15, Ruby Reynolds has contributed to naming the new species and is already a published scientist, listed as a contributor to research in the journal PLoS ONE.

Read more:

Source: www.sciencefocus.com

A newly discovered kangaroo lizard species found in India

Posted on by
Reply

A research team led by scientists from Calicut University has described a new species of agamid lizard discovered in the Indian state of Kerala.

Agastya Gama Edge, an uncollected female from the reference locality habitat of Kuramab, Idukki District, Kerala, India. Image credit: Sandeep Das.

The newly confirmed species belong to the following: Agastya Gama, a previously monotypic genus of diurnal, terrestrial, insectivorous lizards of the family Agamiidae.

This genus includes Indian Kangaroo Lizard (Agastya Gama Bed Dormitory) Originally from the Indian states of Tamil Nadu and Kerala.

“Terrestrial agamids, which inhabit the forests of southern India and Sri Lanka, are currently classified into two separate genera. Agastya Gama and Otocryptis It is based on genetic and morphological grounds,” said Calicut University researcher Sandeep Das and colleagues.

“Genus Otocryptis It originally included two species. Otocryptis Bed Dormitory From the southern Western Ghats of India, Otocryptis wigmannii It comes from the humid region of Sri Lanka. ”

“After a long gap, additional species Otocryptis nigristigma Illustrated from the dry forests of Sri Lanka. ”

“In 2018, scientists showed that the Sri Lankan kangaroo skink is paraphyletic with the Western Ghats kangaroo skink.”

“This prompted them to establish a monotypic genus.” Agastya Gama to accommodate Indians. Otocryptis Bed Dormitory however, no molecular data are available. Otocryptis nigristigma”

Agastya Gama Edge Lifetime: (A) An unrecovered adult male from Kuramab, Idukki District, Kerala, India. (B) Females not collected from the same locality. Image credit: Sandeep Das.

named Agastya Gama EdgeThe new species is a small agamid lizard with a body length of 3 to 4.3 centimeters.

“Agastya Gama Edge It is the second species of the genus Agastya Gama” said the researchers.

“On the surface, they are similar. Agastya Gama Bed Dormitory They vary in overall shape, size, and color, but can be distinguished by the combination of letters. ”

Agastya Gama Edge It is currently known only from evergreen forests in the Idukki district of Kerala, India. All records of this species are between 636 and 835 m above sea level.

“We encountered more individuals from March to May,” the scientists said.

“Disturbed habitats such as roadside vegetation and plantation areas had lower numbers compared to undisturbed vegetation types.”

“During the breeding season from March to May, males had creamy spots on their throats. Young individuals were observed in June and July.”

“Discovery of the second species Agastya Gama “The reptile diversity of the Western Ghats is increasing,” they added.

“Agastya Gama Bed Dormitory Its range is home to a variety of habitat types, including myristica wetlands, hilltop tropical evergreen forests in the south, tropical evergreen forests on the west coast, tropical semi-evergreen forests on the west coast, and secondary moist mixed deciduous forests in the south. I am. Agastya Gama Edge So far it has been recorded only from tropical semi-evergreen and evergreen forests. ”

“Our study shows that the two species are geographically separated by about 80 km in a straight line.”

discovery of Agastya Gama Edge is explained in paper It was published in the magazine vertebrate zoology.

_____

S. Das other. 2024. Discovery of a new species of kangaroo lizard (Squamatora: Agamiidae: Agastya Gama) from the southern Western Ghats of India. vertebrate zoology 74: 151-168; doi: 10.3897/vz.74.e113084

Source: www.sci.news