Jurassic crocodile, new discovery

This 11 May 2018 video says about itself:

A 180-million-year-old fossil has revealed an odd creature, a crocodile with a tail like a dolphin, shedding light on the evolution of these ancient animals and how they became some of the greatest predators of the Jurassic period. Researchers are hailing this new species as a “missing link” in the crocodile family tree.

Their findings, published in PeerJ, are helping to explain how some ancient crocodiles evolved into dolphin-like creatures.

It all began in 1996, when an amateur collector found the fossil on a mountainside in the Gerecse Mountains of north-west Hungary. The specimen was stored at the Hungarian Natural History Museum in Budapest until in 2017, researchers examined it more thoroughly and noticed the odd-looking vertebra on its tail fin.

During the Lower Jurassic, there existed crocodiles that had bony armor on their backs and bellies and had adapted to walk on land. There were also ones that had evolved flippers and had tail fins, but no armor. This fossil, however, appeared to have been both heavily armored and have a tail fin, making it not only a new species, but, according to the researchers, the missing link between the two groups.

Read more here.

From the University of Edinburgh in Scotland:

Jurassic fossil tail tells of missing link in crocodile family tree

May 11, 2018

A 180-million-year-old fossil has shed light on how some ancient crocodiles evolved into dolphin-like animals.

The specimen — featuring a large portion of backbone — represents a missing link in the family tree of crocodiles, and was one of the largest coastal predators of the Jurassic Period, researchers say.

The newly discovered species was nearly five metres long and had large, pointed teeth for grasping prey. It also shared key body features seen in two distinct families of prehistoric crocodiles, the team says.

Some Jurassic-era crocodiles had bony armour on their backs and bellies, and limbs adapted for walking on land. Another group had tail fins and flippers but did not have armour.

The new species was heavily armoured but also had a tail fin, suggesting it is a missing link between the two groups, researchers say.

It has been named Magyarosuchus fitosi in honour of the amateur collector who discovered it, Attila Fitos.

The fossil — unearthed on a mountain range in north-west Hungary in 1996 and stored in a museum in Budapest — was examined by a team of palaeontologists, including a researcher from the University of Edinburgh.

It was identified as a new species based on the discovery of an odd-looking vertebra that formed part of its tail fin.

The study, published in the journal PeerJ, also involved researchers in Hungary and Germany. It was supported by the Leverhulme Trust and the SYNTHESYS project, part of the European Commission’s Seventh Framework Programme.

Dr Mark Young, of the University of Edinburgh’s School of GeoSciences, who was involved in the study, said: “This fossil provides a unique insight into how crocodiles began evolving into dolphin and killer whale-like forms more than 180 million years ago. The presence of both bony armour and a tail fin highlights the remarkable diversity of Jurassic-era crocodiles.”


Crocodiles listen to classical music

This 2016 video is called Alligators, Crocodiles an[d other] Reptiles – SlideShow With Relaxing Classical Music

After the great tit dancing to ABBA music … now this.

From Ruhr-University Bochum in Germany:

Crocodiles listen to classical music in MRI scanner

May 3, 2018

What happens in a crocodile‘s brain when it hears complex sounds? An international research team headed by Dr Felix Ströckens from the Department of Biopsychology at Ruhr-Universität Bochum (RUB) has provided the answer to this question. In a first, the researchers examined a cold-blooded reptile using functional MRI. They were thus able to determine that complex stimuli triggered activation patterns in the crocodile’s brain that are similar to those in birds and mammals — a deep insight into evolution. The results were published in the journal Proceedings of the Royal Society B: Biological Sciences on April 25, 2018.

Link to dinosaurs

Crocodiles count among the most ancient species of vertebrates and have barely changed over the space of more than 200 million years. Accordingly, they constitute a link between dinosaurs and bird species today. “Analyses of crocodile brains thus provide deep insights into the evolution of the nervous system in mammals and may help us understand at which point certain brain structures and behaviours associated therewith were formed”, explains Felix Ströckens.

Overcoming technical obstacles

The objective pursued by the team of researchers from the Iran, South Africa, France, and Germany was to study Nile crocodiles and to ascertain the way sensory information is processed in their brain. To this end, they deployed functional MRI (fMRI) — a method that is routinely used in clinical diagnostics and research, but which has never yet been utilised to study a cold-blooded reptile. “In the first step, we had to overcome a number of technical obstacles,” says research team member Mehdi Behroozi. “For example, we had to adjust the scanner to the crocodile’s physiology, which differs massively from that of mammals in several aspects.”

Astonishing similarity of patterns

Subsequently, the researchers exposed the animals to various visual and auditory stimuli, including classical music by Johann Sebastian Bach. At the same time, they measured the animals’ brain activity. The results have shown that additional brain areas are activated during exposure to complex stimuli such as classical music — as opposed to exposure to simple sounds. The processing patterns strongly resemble the patterns identified in mammals and birds in similar studies.

Processing patterns formed at an early stage

Consequently, the researchers assume that fundamental neuronal processing mechanisms of sensory stimuli formed at an early evolutionary stage and that they can be traced back to the same origins in all vertebrates.

Including fish? Or only tetrapods, land animals?

By successfully deploying fMRI for the examination of a reptile for the first time worldwide, the researchers, moreover, demonstrated that the method does work for poikilothermic organisms. This non-invasive technology can thus be used for many other species that have not yet been studied in depth.

And how would crocodiles and alligators react to this non-classical music?

Brave birds save crocodile eggs from lizard

This video from Africa is called Brave Birds Chasing Monitor Lizard To Save Crocodile Eggs | Animals Save Other Animals.

The birds are stone-curlews. The lizard is a Nile monitor. The crocodile is a Nile crocodile.

Hippos save zebra from crocodile

This January 2018 video from Africa is about a hipps saving a zebra from a crocodile.

Community ecologists have found that global change may alter the way that hippos shape the environment around them: here.

Alligators in North Carolina, USA survive winter

This video from the USA says about itself:

Alligators on Ice: North Carolina reptiles strong survival skills on show

9 jan. 2018

Alligators in North Carolina are dealing with the freezing temperatures by sticking their noses up through the ice to breathe.

South African hippos attack crocodile

This video from Kruger National Park in South Africa says about itself:

30+ Hippos Attack One Crocodile

24 October 2017

Watch this Clash of the Titans take place between the masters of the waters, as these hippos refuse to allow this crocodile into their territory and quickly make sure they remove him from their space.

Harish Kumar (71), a retired sonographer recalled this battled and told Latestsightings.com how it all came about: “We were traveling in a Dutch group of about 18 people. It was a gorgeous day and we only had 2 days of holiday left. Our guide took us out on a drive to the Hippo Pool.

We were all just strolling around everywhere when suddenly my wife called me to tell me that something was going on there in the pool. I ran to get there and immediately started filming immediately – there wasn’t even time to get the tripod set up. Luck was absolutely on my side as I was able to stand with my camera in the right place to film. This was just an unbelievable sighting. The crocodile has somehow managed to maneuver himself into the middle of a pod of angry hippos. These guys wanted him out of their territory immediately. The croc was completely outnumbered and found himself being thrown around and bitten by the hippos. Luckily he managed to get away unharmed. This was a right time right place encounter.”

‘Crocodiles, not Stone Age humans, killed animals’

This video says about itself:

10 November 2009

Paul Sereno and his team of scientists and artists show us what the world looked like in an age when crocs ate dinosaurs.

By Bruce Bower, 3:16pm, November 6, 2017:

Crocs take a bite out of claims of ancient stone-tool use

Scars left on bones could have come from hungry reptiles instead of Stone Age butchery, researchers say

Recent reports of African and North American animal fossils bearing stone-tool marks from being butchered a remarkably long time ago may be a crock. Make that a croc.

Crocodile bites damage animal bones in virtually the same ways that stone tools do, say paleoanthropologist Yonatan Sahle of the University of Tübingen in Germany and his colleagues. Animal bones allegedly cut up for meat around 3.4 million years ago in East Africa (SN: 9/11/10, p. 8) and around 130,000 years ago in what’s now California (SN: 5/27/17, p. 7) come from lakeside and coastal areas. Those are places where crocodiles could have wreaked damage now mistaken for butchery, the scientists report online the week of November 6 in the Proceedings of the National Academy of Sciences.

Larger samples of animal fossils, including complete bones from various parts of the body, are needed to begin to tease apart the types of damage caused by stone tools, crocodile bites and trampling of bones by living animals, Sahle’s team concludes. “More experimental work on bone damage caused by big, hungry crocs is also critical,” says coauthor Tim White, a paleoanthropologist at the University of California, Berkeley.

In a field where researchers reap big rewards for publishing media-grabbing results in high-profile journals, such evidence could rein in temptations to over-interpret results, says archaeologist David Braun of George Washington University in Washington, D.C., who did not participate in the new study or the two earlier ones. “There’s a push to publish extraordinary findings, but evolutionary researchers always have to weigh what’s interesting versus what’s correct.”

Authors of the ancient butchery papers agree that bone marks made by crocodiles deserve closer study and careful comparison with proposed stone-tool marks. But the researchers stand their ground on their original conclusions.

Microscopic investigations in the 1980s led some researchers to conclude that carnivores such as hyenas leave U-shaped marks on bones. In contrast, they argued, stone tools leave V-shaped incisions with internal ridges. And hammering stones create signature pits and striations.

Sahle’s group expanded on research previously conducted by paleoanthropologist Jackson Njau of Indiana University Bloomington. In his 2006 doctoral dissertation, Njau reported that bone damage produced by feeding crocodiles looks much like stone-tool incisions and pits, with a few distinctive twists such as deep scratches. Njau retrieved and studied cow and goat bones from carcasses that had been eaten by crocodiles housed at two animal farms in Tanzania.

In the new study, the scientists used Njau’s findings to reassess marks on fossils previously excavated in Ethiopia and dating to around 4.2 million, 3.4 million and 2.5 million years ago. Damage to these fossils has generally been attributed to butchery with stone tools.

Incisions and pits on arm bones from an ancient hominid, Australopithecus anamensis, and similar marks on a horse’s leg bone likely resulted from crocodile bites and not stone-tool use, as initially suspected, the investigators say. If stone tools had indeed damaged the A. anamensis remains, that would raise the possibility of cannibalism — a difficult behavior to confirm with fossils. Tellingly, Sahle’s team argues, these bones come from what were once waterside areas. Some were found in the same sediment layer as crocodile remains. Marks on these bones include deep scratches consistent with crocodile bites.

The horse fossil comes from a spot along an ancient lakeshore where no stone tools have been found, a further clue in favor of damage from croc bites.

Jagged pits, incisions and other marks scar a leg fragment and lower jaw from an ancient hoofed animal. But microscopic analyses could not definitively attribute the damage to stone tools or crocodile bites.

In light of these findings, the ancient California and 3.4-million-year-old East Africa bones should also be reexamined with the possibility of croc damage in mind, White says. For now, the earliest confirmed stone-tool marks occur on animal bones from two East African sites dating to around 2.5 million years ago (SN: 4/17/04, p. 254), he adds.

The range of crocodile marks described in the new study doesn’t look “especially like” damage to the 130,000-year-old mastodon bones on California’s coast, says paleontologist Daniel Fisher of the University of Michigan in Ann Arbor, a coauthor of the ancient California bones paper. No fossil evidence indicates crocodiles lived there at that time, he adds. Several lines of evidence, including pounding marks and damage near joints, point to stone-tool use at the West Coast site, says archaeologist Richard Fullagar of the University of Wollongong in Australia, also a coauthor of the mastodon paper.

Further studies of the 3.4-million-year-old African bones previously reported as probable examples of animal butchery will statistically compare the probability of various causes for particular marks, including crocodile bites, says Shannon McPherron, the lead author of the earlier study and an archaeologist at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany. In that way, researchers can assess whether any one cause stands out as the strongest candidate.