Big flowering trees in dinosaur age North America


This video from the USA says about itself:

27 July 2018

In this episode of the Rocks of Utah I join paleontologist David Wilcots on a trip to the late Cretaceous Mesa Verde Group in search of dinosaurs!

The Rocks of Utah is a YouTube series that explores the unique geology of Utah, and hosted by Benjamin Burger, a geology professor at Utah State University Uintah Basin Campus in Vernal, Utah.

From Adelphi University in the USA:

Fossil evidence of large flowering trees in N. America 15 millions years earlier

September 26, 2018

A newly discovered fossil suggests that large, flowering trees grew in North America by the Turonian age, showing that these large trees were part of the forest canopies there nearly 15 million years earlier than previously thought. Researchers from Adelphi University and the Burpee Museum of Natural History found the fossil in the Mancos Shale Formation in Utah, in ancient delta deposits formed during a poorly understood interval in the North American fossil record.

“These discoveries add much more detail to our picture of the landscape during the Turonian period than we had previously”, says Michael D’Emic, assistant professor of biology at Adelphi, who organized the study. “Since Darwin, the evolution of flowering plants has been a topic of debate for paleontologists because of their cryptic fossil record. Our paper shows that even today it is possible for a single fossil specimen to change a lot about what we know about the early evolution of the group.

“Understanding the past is the key to managing the future”, D’Emic added. “Learning how environments evolved and changed in the past teaches us how to better prepare for future environmental change.”

Aside from the large petrified log, the team reports fossilized foliage from ferns, conifers and angiosperms, which confirm that there was forest or woodland vegetation 90 million years ago in the area, covering a large delta extending into the sea. The team also reports the first turtle and crocodile remains from this geologic layer, as well as part of the pelvis of a duck-billed dinosaur; previously, the only known vertebrate remains found were shark teeth, two short dinosaur trackways, and a fragmentary pterosaur.

“Until now most of what we knew about plants from the Ferron Sandstone came from fossil pollen and spores”, says Nathan Jud, co-author and assistant professor of biology at William Jewell College. “The discovery of fossil wood and leaves allows us to develop a more complete picture of the flora.”

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Madagascar’s extinct elephant birds, biggest birds ever


This April 2018 video says about itself:

Elephant Birds || These Giants Roamed In Madagascar Until Just A Few Centuries Ago

Elephant birds were large to enormous flightless birds that once lived on the island of Madagascar.

They became extinct, by the 17th or 18th century if not earlier, for reasons that are unclear, although human activity is the suspected cause.

From the Zoological Society of London:

World’s largest ever bird has been named: Vorombe titan

Madagascar’s giant elephant birds receive ‘bone-afide’ rethink

September 26, 2018

After decades of conflicting evidence and numerous publications, scientists at international conservation charity ZSL’s (Zoological Society of London) Institute of Zoology, have finally put the ‘world’s largest bird’ debate to rest. Published today (26 September 2018) in Royal Society Open Science — Vorombe titan (meaning ‘big bird’ in Malagasy and Greek), has taken the title reaching weights of up to 800 kg and three metres tall, with the research also discovering unexpected diversity in these Madagascan creatures.

Until now, it was previously suggested that up to 15 different species of elephant birds had been identified under two genera, however research by ZSL scientists boasts new rigorous and quantitative evidence — that shows, in fact, this is not the case. Armed with a tape measure and a pair of callipers, Dr Hansford analysed hundreds of elephant bird bones from museums across the globe to uncover the world’s largest bird, while also revealing their taxonomy is in fact spread across three genera and at least four distinct species; thus, constituting the first taxonomic reassessment of the family in over 80 years.

Elephant birds (belonging to the family Aepyornithidae) are an extinct group of colossal flightless birds that roamed Madagascar during the Late Quaternary, with two genera (Aepyornis and Mullerornis) previously recognised by scientists. The first species to be described, Aepyornis maximus, has often been considered to be the world’s largest bird. In 1894, British scientist C.W. Andrews described an even larger species, Aepyornis titan, this has usually been dismissed as an unusually large specimen of A. maximus. However, ZSL’s research reveals Andrew’s ‘titan’ bird was indeed a distinct species. The shape and size of its bones are so different from all other elephant birds that it has now been given the new genus name Vorombe by ZSL.

Lead Author at ZSL’s Institute of Zoology, Dr James Hansford said: “Elephant birds were the biggest of Madagascar’s megafauna and arguably one of the most important in the island’s evolutionary history — even more so than lemurs. This is because large-bodied animals have an enormous impact on the wider ecosystem they live in via controlling vegetation through eating plants, spreading biomass and dispersing seeds through defecation. Madagascar is still suffering the effects of the extinction of these birds today.”

Co-Author Professor Samuel Turvey from ZSL’s Institute of Zoology said: “Without an accurate understanding of past species diversity, we can’t properly understand evolution or ecology in unique island systems such as Madagascar or reconstruct exactly what’s been lost since human arrival on these islands. Knowing the history of biodiversity loss is essential to determine how to conserve today’s threatened species.”

Analysing this data in a novel combination of machine learning combined with Bayesian clustering, Dr Hansford applied modern techniques to solve a 150-year-old taxonomic knot, that will form the modern understanding of these enigmatic avian megafauna. The revelation that the biggest of these birds was forgotten by history is just one part of their remarkable story.

Extinct mice discovery in Australia


This 2014 video from Australia says about itself:

Describes the Desert or Spinifex Hopping Mouse [Notomys alexis], its features, habitat, nocturnal activities etc.

From the University of Queensland in Australia:

Ancient mice discovered by climate cavers

September 24, 2018

The fossils of two extinct mice species have been discovered in caves in tropical Queensland by University of Queensland scientists tracking environment changes.

Fossils of Webb’s short-tailed mouse (Leggadina webbi) were found at Mount Etna near Rockhampton, while Irvin’s short-tailed mouse (Leggadina irvini), was discovered near Chillagoe at the base of Cape York Peninsula.

Dr Jonathan Cramb from UQ’s School of Earth and Environmental Sciences said the finds show that analysing fossils found in caves could help determine how the local environment had changed over time.

“Caves are great places for the preservation of fossils, partially because they’re natural traps that animals fall into, but also because they’re roosting sites for owls and other flying predators”, he said.

“Owls are exceptionally good at catching small mammals in particular, so the cave floor beneath their roosts is littered with the bones of rodents and small marsupials.

“The accumulation of bones build up over time, providing us with a record of what species were living in the local area, which can stretch back hundreds of thousands of years.

“Many species are only found in certain habitats — for example, hopping mice (Notomys spp.) generally live in deserts, while tree mice (Pogonomys spp.) only live in rainforests — so changes in the fauna tell us about changes in the environment.”

Dr Cramb said the team, including UQ’s Dr Gilbert Price and alumnus Scott Hocknull from the Queensland Museum, was able to confirm a number of environmental changes thanks to the fossils.

Our findings show that the caves around Mount Etna had gone through a period of local extinction of rainforests, which were replaced by dry to arid habitats less than 280,000 years ago”, Dr Cramb said.

“My colleagues and I wondered if the same environmental change happened elsewhere in Queensland, which is why we were searching the caves near Chillagoe.

“Our analysis of fossils from the caves in north-east Queensland has shown that rainforest extinction was widespread.

“This research shows that, at least in these instances, rainforest extinction is correlated with a sudden shift in climate — a warning that rainforests are particularly vulnerable to climate change.”

The new species of mice were named after UQ palaeontologist Professor Gregory Webb and citizen scientist and caving guide Douglas Irvin.

World’s oldest animal discovery in Russia


This 20 September 2018 Australian National University says about itself:

Is Dickinsonia our oldest ancestor?

Scientists from ANU have discovered molecules of fat in an ancient fossil to reveal the earliest confirmed animal in the geological record that lived on Earth 558 million years ago. The strange creature called Dickinsonia, which grew up to 1.4 metres in length and was oval shaped with rib-like segments running along its body, was part of the Ediacara Biota that lived on Earth 20 million years prior to the ‘Cambrian explosion’ of modern animal life.

From Australian National University:

Fat from 558 million years ago reveals earliest known animal

September 20, 2018

Scientists from The Australian National University (ANU) and overseas have discovered molecules of fat in an ancient fossil to reveal the earliest confirmed animal in the geological record that lived on Earth 558 million years ago.

The strange creature called Dickinsonia, which grew up to 1.4 metres in length and was oval shaped with rib-like segments running along its body, was part of the Ediacara Biota that lived on Earth 20 million years prior to the ‘Cambrian explosion‘ of modern animal life.

ANU PhD scholar Ilya Bobrovskiy discovered a Dickinsonia fossil so well preserved in a remote area near the White Sea in the northwest of Russia that the tissue still contained molecules of cholesterol, a type of fat that is the hallmark of animal life.

Lead senior researcher Associate Professor Jochen Brocks said the ‘Cambrian explosion’ was when complex animals and other macroscopic organisms — such as molluscs, worms, arthropods and sponges — began to dominate the fossil record.

“The fossil fat molecules that we’ve found prove that animals were large and abundant 558 million years ago, millions of years earlier than previously thought”, said Associate Professor Jochen Brocks from the ANU Research School of Earth Sciences.

“Scientists have been fighting for more than 75 years over what Dickinsonia and other bizarre fossils of the Edicaran Biota were: giant single-celled amoeba, lichen, failed experiments of evolution or the earliest animals on Earth. The fossil fat now confirms Dickinsonia as the oldest known animal fossil, solving a decades-old mystery that has been the Holy Grail of palaeontology.”

Mr Bobrovskiy said the team developed a new approach to study Dickinsonia fossils, which hold the key between the old world dominated by bacteria and the world of large animals that emerged 540 million years ago during the ‘Cambrian explosion‘.

“The problem that we had to overcome was finding Dickinsonia fossils that retained some organic matter”, said Mr Bobrovskiy from the ANU Research School of Earth Sciences.

“Most rocks containing these fossils such as those from the Ediacara Hills in Australia have endured a lot of heat, a lot of pressure, and then they were weathered after that — these are the rocks that palaeontologists studied for many decades, which explained why they were stuck on the question of Dickinsonia’s true identity.”

Palaeontologists normally study the structure of fossils, but Mr Bobrovskiy extracted and analysed molecules from inside the Dickinsonia fossil found in ancient rocks in Russia to make the breakthrough discovery.

“I took a helicopter to reach this very remote part of the world — home to bears and mosquitoes — where I could find Dickinsonia fossils with organic matter still intact”, Mr Bobrovskiy said.

“These fossils were located in the middle of cliffs of the White Sea that are 60 to 100 metres high. I had to hang over the edge of a cliff on ropes and dig out huge blocks of sandstone, throw them down, wash the sandstone and repeat this process until I found the fossils I was after.”

Associate Professor Brocks said being able to study molecules from these ancient organisms was a gamechanger.

“When Ilya showed me the results, I just couldn’t believe it,” he said.

“But I also immediately saw the significance.”

ANU led the research in collaboration with scientists from the Russian Academy of Science and the Max Planck Institute for Biogeochemistry and the University of Bremen in Germany.

Reptile to mammal evolution, new research


This 2017 video is about the evolution of reptiles, ancestral to mammals.

From the National Science Foundation in the USA:

What makes a mammal a mammal? Our spine, say scientists

Study of fossil bones leads to new conclusions about spine’s importance

September 20, 2018

Mammals are unique in many ways. We’re warm-blooded and agile in comparison with our reptilian relatives.

But a new study, funded by the National Science Foundation (NSF) and led by Harvard University researchers Stephanie Pierce and Katrina Jones, suggests we’re unique in one more way — the makeup of our spines. The researchers describe their finding in a paper published this week in the journal Science.

“The spine is basically like a series of beads on a string, with each bead representing a single bone — a vertebra,” said Pierce, curator of vertebrate paleontology at Harvard. “In most four-legged animals, like lizards, the vertebrae all look and function the same.

“But mammal backbones are different. The different sections or regions of the spine — like the neck, thorax and lower back — take on very different shapes. They function separately and so can adapt to different ways of life, like running, flying, digging and climbing.”

While mammal backbones are specialized, the regions that underlie them were believed to be ancient, dating back to the earliest land animals.

Mammals made the most of the existing anatomical blueprint, or so scientists believed. However, the new study is challenging this idea by looking into the fossil record.

“There are no animals alive today that record the transition from a ‘lizard-like’ ancestor to a mammal“, said Jones, lead author of the study. “To do that, we have to dive into the fossil record and look at the extinct forerunners of mammals, the non-mammalian synapsids.”

These ancient ancestors hold the key to understanding the origin of mammal-specific characteristics, including the spine.

But studying fossils isn’t easy. “Fossils are scarce and finding extinct animals with all 25-plus vertebrae in place is incredibly rare”, Jones said.

To tackle this problem, the researchers combed museum collections around the world to study the best-preserved fossils of animals that lived some 320 million years ago.

“Looking into the ancient past, an early change in mammals’ spinal columns was an important first step in their evolution”, said Dena Smith, a program director in NSF’s Division of Earth Sciences, which funded the research. “Changes in the spine over time allowed mammals to develop into the myriad species we know today.”

Pierce and Jones, along with co-author Ken Angielczyk of the Field Museum in Chicago, examined dozens of fossil spines, as well as more than 1,000 vertebrae of living animals, including mice, alligators, lizards and amphibians.

They wanted to find out whether mammal vertebral regions were as ancient as previously thought, or if mammals were doing something unique.

“If vertebral regions had remained unchanged through evolution, as hypothesized, we would expect to see the same regions in the non-mammalian synapsids that we see in mammals today”, said Pierce.

But that doesn’t seem to be the case. When the researchers compared the positioning and shape of the vertebrae, they found something surprising. The spine had gained new regions during mammal evolution.

“The earliest non-mammalian synapsids had fewer regions than living mammals”, said Jones.

About 250 million years ago, a new region evolved near the shoulders and front legs. Dramatic changes also began to appear in the forelimbs of animals known as non-mammalian therapsids.

These simultaneous developments, the scientists believe, likely occurred in conjunction with changes in how creatures walked and ran.

“There appears to be some sort of cross-talk during development between the tissues that form the vertebrae and the shoulder blade”, Pierce said. “We think this interaction resulted in the addition of a region near the shoulder as the forelimbs of our ancestors evolved to take on new shapes and functions.”

Later, a region emerged near the pelvis. “It is this last region, the ribless lumbar region, that appears to be able to adapt the most to different environments”, said Pierce.

The final step in building the mammal backbone may be linked with changes in Hox genes, important to spine regions early in their development.

“We’ve been able to make connections among changes in the skeletons of extinct animals and ideas in modern developmental biology and genetics”, Jones said. “This combined approach is helping us understand what makes a mammal a mammal.”

Ancient Mesosaurus reptiles, aquatic or semi-aquatic?


This 2015 video says about itself:

“Mesosaurs” were a group of small aquatic reptiles that lived during the early Permian period, roughly 299 to 270 million years ago. Mesosaurs were the first aquatic reptiles, having apparently returned to an aquatic lifestyle from more terrestrial ancestors. However, just how terrestrial mesosaur ancestors had become remains uncertain; recent research cannot establish with confidence if the first amniotes were fully terrestrial, or only amphibious.

From Frontiers in Ecology and Evolution:

Oldest-known aquatic reptiles probably spent time on land

September 19, 2018

The oldest known aquatic reptiles, the mesosaurs, probably spent part of their life on land, reveals a new study published in Frontiers in Ecology and Evolution. The fossilized bones of adult Mesosaurus share similarities with land-dwelling animals, which — coupled with the relative scarcity of land-weathered fossilized remains of large specimens — suggests that older mesosaurs were semi-aquatic, whereas juveniles spent most of their time in the water. This new research emphasizes the importance of thoroughly analyzing fossilized remains from across all stages of a reptile’s life to get a full appreciation of its lifestyle and behavior.

“Despite being considered the oldest-known fully aquatic reptile, mesosaurs share several anatomical features with terrestrial species”, says Professor Graciela Piñeiro, who completed this research at the Facultad de Ciencias, Universidad de la República, Uruguay. “Our comprehensive analysis of the vertebrae and limbs of these ancient reptiles suggests they lived in the water during the earliest stages of their development, whereas mature adults spent more time on land.”

Since the discovery of unusually large Mesosaurus bones in the Mangrullo Formation of Uruguay, Piñeiro and her international team of colleagues wondered why the larger, presumably adult specimens, around two meters in length, were not as abundant as mesosaur skeletons of around 90 cm.

“The larger specimens, at least twice the length of the more commonly reported Mesosaurus fossils, could just be exceptionally big individuals. However, the environmental conditions of the Mangrullo lagoon of where they lived were harsh, making it difficult for the occasional mesosaur to reach such a relatively large size and age”, explains Piñeiro.

She continues, “We then realized that in comparison to the smaller, better-preserved specimens, larger Mesosaurus fossils were almost always disarticulated, very weathered and badly preserved. This suggested these larger specimens had extended exposure to the air when they died.”

During the reconstruction of a Mesosaurus skeleton and analysis of skeletons representing different life stages of this ancient reptile, the researchers examined the remains for evidence of a terrestrial, land-dwelling existence.

Terrestrial, semi-aquatic and aquatic animals show a clear difference in bone profiles, so they used morphometrics to analyze the shape of the fossilized bones. Forty Mesosaurus specimens, from juveniles to adults, were examined and their bone profiles compared to those of similar reptiles known to be aquatic or semi-aquatic, such as crocodiles and marine iguanas.

“The adult mesosaur tarsus (a cluster of bones in the ankle region) suggests a more terrestrial or amphibious locomotion rather than a fully aquatic behavior as widely suggested before”, says Pablo Núñez, also based at Universidad de la República. “Their caudal vertebrae, the tail bones, also showed similarities to semi-aquatic and terrestrial animals. This supports the hypothesis that the oldest and largest mesosaurs spent more time on land, where fossil preservation is not as good as in the subaquatic domain.”

Published as part of a special article collection on Mesosaurs, these findings have broader implications — both for future research on early prehistoric animals that laid eggs with embryonic membranes and for the understanding of reptile evolution.

Piñeiro explains, “Our study emphasizes the importance of working with fossils representing an entire population of a species, including a wide range of juveniles and adults, before establishing paleobiological interpretations on their lifestyle and behavior.”

She continues, “These findings also have important implications on the inferred lifestyle of species closely related to mesosaurs, particularly in the context of the evolution of the amniotic egg. For instance, thanks to our previous discovery of a mesosaur egg and embryos inside the mother’s body, our new findings can give support to earlier hypotheses suggesting that the amniotic egg might have appeared in aquatic or semiaquatic animals as a strategy to leave the water to avoid predation.”

Top 15 largest sharks of all time


This 19 September 2018 video says about itself:

15 Largest Sharks to Ever Exist – Comparison

This is another video on the size comparison of sharks but on this one we will showcase the 15 largest sharks to ever have existed which includes extinct giant sharks and the existing / alive sharks we have today.

Sharks have existed in the past that were way bigger than modern-day sharks and they even dwarf the great white in size. Some sharks were even as big as the modern-day basking and whale sharks.

The Meg / Megalodon has his competition by some of these species of sharks in comparison in size and ferociousness.

The 15 largest sharks include the biggest sharks from modern day and they rank way down in comparison to some sharks like the primitive Helicoprion, the ginsu shark and the Megalodon.

The primitive Otodus is one shark that can rival the lesser Megalodon specimens in size … So enjoy this video on the 15 largest sharks to ever exist – comparison.