Megalodon, glyptodon fossil discovery in Florida, USA


This 14 October 2019m video from the USA says about itself:

Finding a Megalodon Shark Tooth & Glyptodon (Giant Armadillo) Fossils in a Florida River!

The best of both worlds! In this video we got out for some Megalodon shark tooth hunting, but also found some incredibly nice Glyptodon scutes! Glyptodon is a giant armadillo-like animal from the Pleistocene (1.8 million to 10,000 years ago) the size of a Volkswagen Beetle! This was definitely an adventure as the water was very low and we had to drag the canoe all through the swamp.

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New big dinosaur species discovered in Thailand


Siamraptor suwati reconstruction

From PLOS:

Meet Siamraptor suwati, a new species of giant predatory dinosaur from Thailand

Siamraptor provides a new glimpse at the early evolution of carcharodontosaurian dinosaurs

October 9, 2019

Fossils discovered in Thailand represent a new genus and species of predatory dinosaur, according to a study released October 9, 2019 in the open-access journal PLOS ONE by Duangsuda Chokchaloemwong of Nakhon Ratchasima Rajabhat University, Thailand and colleagues.

Carcharodontosaurs were a widespread and successful group of large predatory dinosaurs during the Jurassic and Cretaceous Periods and were important members of ecosystems on multiple continents. However, the fossil record of these animals is notably lacking from the Early Cretaceous of Asia, with no definite carcharodontosaurs known from Southeast Asia.

In this study, Chokchaloemwong and colleagues describe fossil material from the Khok Kruat geologic formation in Khorat, Thailand, dating to the Early Cretaceous. These fossils include remains of the skull, backbone, limbs, and hips of at least four individual dinosaurs, and morphological comparison with known species led the authors to identify these remains as belonging to a previously unknown genus and species of carcharodontosaur which they named Siamraptor suwati.

Phylogenetic analysis indicates that Siamraptor is a basal member of the carcharodontosaurs, meaning it represents a very early evolutionary split from the rest of the group. It is also the first definitive carcharodontosaur known from Southeast Asia, and combined with similarly-aged finds from Europe and Africa, it reveals that this group of dinosaurs had already spread to three continents by the Early Cretaceous.

Neanderthals and art, videos


This 9 October 2019 video says about itself:

There is a huge debate around whether and to what extent Neanderthals made art. Here to help me set the record straight is Dr. Wragg Sykes, Neanderthal expert, archaeologist and author.

Sites mentioned in the interview:

Bruniquel Cave, France

Cioarei-Borosteni, Romania

Fumane Cave, Italy

This video is about the Bruniquel cave.

Invertebrate fossils discovery in Dominican Republic amber


Sialomorpha dominicana

From Oregon State University in the USA:

Meet the ‘mold pigs,’ a new group of invertebrates from 30 million years ago

October 8, 2019

Fossils preserved in Dominican amber reveal a new family, genus and species of microinvertebrate from the mid-Tertiary period, a discovery that shows unique lineages of the tiny creatures were living 30 million years ago.

The findings by George Poinar Jr. of the Oregon State University College of Science give a rare look at a heretofore unknown clade of invertebrates, along with their fungal food source and other animals that lived in their habitat.

Poinar, an international expert in using plant and animal life forms preserved in amber to learn more about the biology and ecology of the distant past, informally calls the new animals “mold pigs” for their resemblance to swine, and their diet. Scientifically, they are Sialomorpha dominicana, from the Greek words for fat hog (sialos) and shape (morphe).

Invertebrate means not having a backbone, and invertebrates account for roughly 95 percent of animal species.

“Every now and then we’ll find small, fragile, previously unknown fossil invertebrates in specialized habitats,” Poinar said. “And occasionally, as in the present case, a fragment of the original habitat from millions of years ago is preserved too. The mold pigs can’t be placed in any group of currently existing invertebrates — they share characteristics with both tardigrades, sometimes referred to as water bears or moss pigs, and mites but clearly belong to neither group.”

The several hundred individual fossils preserved in the amber shared warm, moist surroundings with pseudoscorpions, nematodes, fungi and protozoa, Poinar said.

“The large number of fossils provided additional evidence of their biology, including reproductive behavior, developmental stages and food,” he said. “There is no extant group that these fossils fit into, and we have no knowledge of any of their descendants living today. This discovery shows that unique lineages were surviving in the mid-Tertiary.”

The Tertiary period began 65 million years ago and lasted for more than 63 million years.

About 100 micrometers long, the mold pigs had flexible heads and four pairs of legs. They grew by molting their exoskeleton and fed mainly on fungi, supplementing that food source with small invertebrates.

“No claws are present at the end of their legs as they are with tardigrades and mites,” Poinar said. “Based on what we know about extant and extinct microinvertebrates, S. dominicana appears to represent a new phylum. The structure and developmental patterns of these fossils illustrate a time period when certain traits appeared among these types of animals. But we don’t know when the Sialomorpha lineage originated, how long it lasted, or whether there are descendants living today.”

Last woolly mammoths, 4,000 years ago


This August 2014 video from London, England says about itself:

The last of the mammoths | Natural History Museum

Why did the woolly mammoth go extinct? Museum mammoths expert Professor Adrian Lister discusses what his research reveals about the cause. Find out more about Museum research into the last major extinction of large mammals.

From the University of Helsinki in Finland:

The last mammoths died on a remote island

October 7, 2019

The last woolly mammoths lived on Wrangel Island in the Arctic Ocean; they died out 4,000 years ago within a very short time. An international research team from the Universities of Helsinki and Tübingen and the Russian Academy of Sciences has now reconstructed the scenario that could have led to the mammoths‘ extinction. The researchers believe a combination of isolated habitat and extreme weather events, and even the spread of prehistoric man may have sealed the ancient giants’ fate. The study has been published in the latest edition of Quaternary Science Reviews.

During the last ice age — some 100,000 to 15,000 years ago — mammoths were widespread in the northern hemisphere from Spain to Alaska. Due to the global warming that began 15,000 years ago, their habitat in Northern Siberia and Alaska shrank. On Wrangel Island, some mammoths were cut off from the mainland by rising sea levels; that population survived another 7000 years.

The team of researchers from Finland, Germany and Russia examined the isotope compositions of carbon, nitrogen, sulfur and strontium from a large set of mammoth bones and teeth from Northern Siberia, Alaska, the Yukon, and Wrangel Island, ranging from 40,000 to 4,000 years in age. The aim was to document possible changes in the diet of the mammoths and their habitat and find evidence of a disturbance in their environment. The results showed that Wrangel Island mammoths’ collagen carbon and nitrogen isotope compositions did not shift as the climate warmed up some 10,000 years ago. The values remained unchanged until the mammoths disappeared, seemingly from the midst of stable, favorable living conditions.

This result contrasts with the findings on woolly mammoths from the Ukrainian-Russian plains, which died out 15,000 years ago, and on the mammoths of St. Paul Island in Alaska, who disappeared 5,600 years ago. In both cases, the last representatives of these populations showed significant changes in their isotopic composition, indicating changes in their environment shortly before they became locally extinct.

Earlier aDNA studies indicate that the Wrangel Island mammoths suffered mutations affecting their fat metabolism. In this study, the team found an intriguing difference between the Wrangel Island mammoths and their ice age Siberian predecessors: the carbonate carbon isotope values indicated a difference in the fats and carbohydrates in the populations’ diets. “We think this reflects the tendency of Siberian mammoths to rely on their reserves of fat to survive through the extremely harsh ice age winters, while Wrangel mammoths, living in milder conditions, simply didn’t need to,” says Dr. Laura Arppe from the Finnish Museum of Natural History Luomus, University of Helsinki, who led the team of researchers. The bones also contained levels of sulfur and strontium that suggested the weathering of bedrock intensified toward the end of the mammoth population’s existence. This may have affected the quality of the mammoths’ drinking water.

Why then did the last woolly mammoths disappear so suddenly? The researchers suspect that they died out due to short-term events. Extreme weather such as a rain-on-snow, i.e. an icing event could have covered the ground in a thick layer of ice, preventing the animals from finding enough food. That could have led to a dramatic population decline and eventually to extinction. “It’s easy to imagine that the population, perhaps already weakened by genetic deterioration and drinking water quality issues could have succumbed after something like an extreme weather event,” says professor Hervé Bocherens from the Senckenberg Center for Human Evolution and Palaeoenvironment at the University of Tübingen, a co-author of the study.

Another possible factor could have been the spread of humans. The earliest archaeological evidence of humans on Wrangel Island dates to just a few hundred years after the most recent mammoth bone. The chance of finding evidence that humans hunted Wrangel Island mammoths is very small. Yet a human contribution to the extinction cannot be ruled out.

The study shows how isolated small populations of large mammals are particularly at risk of extinction due to extreme environmental influences and human behavior. An important takeaway from this is that we can help preserve species by protecting the populations that are not isolated from one another.

Stick insect evolution, birds and mammals


This 8 October 2019 video says about itself:

These Giant Leaf Insects Will Sway Your Heart | Deep Look

Giant Malaysian leaf insects stay still – very still – on their host plants to avoid hungry predators. But as they grow up, they can’t get lazy with their camouflage. They change – and even dance – to blend in with the ever-shifting foliage.

From the University of Göttingen in Germany:

Was early stick insect evolution triggered by birds and mammals?

October 7, 2019

Stick and leaf insects are a diverse and strikingly bizarre group of insects with a worldwide distribution, which are more common in tropical and subtropical areas. They are famous for their impressively large body size, compared to other insects, and their remarkable ability to camouflage themselves as twigs, leaves or bark in order to hide from potential predators. A team of international researchers led by the University of Göttingen has now generated the first phylogenomic tree of these insects. The results have been published in the journal Frontiers in Ecology and Evolution.

“Previously the relationships between stick insects were inferred based on just a handful of genes. This is the first study in which more than 2,000 genes were analysed for each species,” explains Dr Sven Bradler from the University of Göttingen and senior author of the study. 38 species of stick and leaf insects from all over the world were investigated by the researchers of the 1KITE project (1,000 Insect Transcriptome Evolution). “Previous studies were unable to explain the early evolution of these insects. This has now changed with the new and much more extensive dataset that can even reconstruct the origin of the oldest lineages,” adds Dr Sabrina Simon, first author of this study from the University Wageningen.

The most surprising finding is that the relationships between the early emerging groups of stick and leaf insects largely disprove the earlier assumptions. In fact, the genealogy reflects more the geographic distribution than the anatomical similarity of the animals. The authors revealed a New World lineage of purely North and South American species and a group of Old World origin that comprises species from Africa to New Zealand.

The biogeographic history was reconstructed by Sarah Bank, PhD student at the University of Göttingen and coauthor of the study, which resulted in further unexpected results: “The flamboyant stick insects of Madagascar, for instance, descended from a single ancestral species who colonised the island approximately 45 million years ago.”

The age estimation of the phylogenetic tree suggests that most of the old lineages emerged after the dinosaurs became extinct 66 million years ago. Thus, the remarkable camouflage of stick and leaf insects most probably evolved afterwards as adaptation against predatory mammals and birds.

“Stick insects become more and more important as model organisms for evolutionary research. The new comprehensive molecular dataset won’t be exhaustively analysed for quite some time and will provide exciting insights into the function of the numerous detected genes,” explains Bradler with regard to future studies.

Elephants, extinct and living, size comparison video


This 19 August 2019 video says about itself:

In this video we will compare the size of different elephants and mammoths, ranging from the living African bush elephant and Indian elephant to the extinct mammoths, from woolly mammoth to Palaeoloxodon namadicus.

See also here.