Carboniferous-Permian plant extinction harmed amphibians, helped reptiles


This video says about itself:

30 March 2015

Dave and Palaeo After Dark’s James explore the Carboniferous forests in the ‘Carboniferous Forest Simulator‘!

This fantastic software is free for educational, museum or personal use. We really need to get our full support behind this project!

The programme, in its ‘alpha testing’ stage can be downloaded here.

Details of the development of the project can be found here.

From the University of Birmingham in England:

Rainforest collapse 307 million years ago impacted the evolution of early land vertebrates

February 7, 2018

Researchers at the University of Birmingham have discovered that the mass extinction seen in plant species caused by the onset of a drier climate 307 million years ago led to extinctions of some groups of tetrapods, the first vertebrates to live on land, but allowed others to expand across the globe. This research is published today (7th February 2018) in the journal Proceedings of the Royal Society B.

The Carboniferous and Permian periods (358 — 272 million years ago) were critical intervals in the evolution of life on land. During the Carboniferous Period North America and Europe lay in a single land mass at the equator which was covered by dense tropical rainforests. These rainforests flourished because of the warm humid climate, providing an ideal habitat for early tetrapods (vertebrates with four limbs), allowing them to diversify into a variety of species.

But towards the end of this period a major global environment change took place — just as the number of tetrapod species began to increase, the rainforests started to disappear. The climate became much drier causing the mass extinction of many species within the dominant plant groups, such as horsetails and club mosses. Despite this being a catastrophic event for plants, it has been unclear how this affected the early tetrapod community.

Previous attempts to estimate the diversity changes during this period have been hindered by the fossil record, which has not been sampled equally in different time intervals or geographic areas. To fill these gaps in the data, the Birmingham researchers compiled a new dataset from the Paleobiology Database and used advanced statistical methods to estimate diversity and biogeographic changes.

The results of the study show that tetrapod diversity decreased after the rainforest collapse and the onset of drier conditions, largely due to the reduction in suitable habitats for amphibians which needed wet environments to survive.

However they also found that after the rainforest collapse surviving tetrapod species began to disperse more freely across the globe, colonising new habitats further from the equator. Many of these survivors were early amniotes, such as early reptiles, whose generally larger size relative to early amphibians allowed them to travel longer distances, and their ability to lay eggs meant they were not confined to watery habitats.

Emma Dunne, from the University of Birmingham’s School of Geography, Earth and Environmental Sciences, said: ‘This is the most comprehensive survey ever undertaken on early tetrapod evolution, and uses many newly developed techniques for estimating diversity patterns of species from fossil records, allowing us greater insights into how early tetrapods responded to the changes in their environment.’

Dunne continued: ‘We now know that the rainiforest collapse was crucial in paving the way for amniotes, the group which ultimately gave rise to modern mammals, reptiles and birds, to become the dominant group of land vertebrates during the Permian period and beyond.’

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Harlequin frogs freed in Panama


This video says about itself:

Hundreds of Tiny Frogs Released on a Mission to Save Their Species | National Geographic

22 January 2018

Scientists released hundreds of harlequin frogs into the wilds of Panama in hopes of collecting valuable data.

We hope these harlequin frogs in Panama are able to create safe, fungus-free areas and revive their species!

Frogs and Dutch song music video


This 25 December 2017 video is about frog species living in the Netherlands. Mainly edible frogs; also a tree frog and an European toad.

The piano music in this video is the tune of the old Dutch children’s song Er zaten zeven kikkertjes al in een boerensloot (There were seven little frogs in a farmer’s ditch). The ditch in the song is frozen, the frogs half dead.

According to Dutch Wikipedia, the song is from 1843.

However, it may be even older. I remember a version of the song with as final lines:

En er kwam een vent uit Pruisen
met honderdduizend man.
Die nam de zeven kikkertjes
en braadde ze in de pan.

Translation:

A guy from Prussia came
with a hundred thousand men.
He took the seven little frogs
and fried them in the pan.

This may mean that the song is from shortly after 1787. Then, the king of Prussia had one of his generals invade the Dutch republic. Not with 100,000 soldiers; with 26,000 soldiers, but it was enough for victory. The aim of the Prussian invasion was to restore the power of Prince William V of the Orange dynasty, who had been driven away from the capital The Hague by the republican Patriot party.

The song may have been meant originally by the pro-Orange dynasty party to mock their Patriot opponents as powerless frogs.

South American amphibian saving human lives?


This February 2017 video, recorded in Costa Rica, is about wildlife, especially the Caecilia volcani species of caecilian amphibians.

From the University of Surrey in England:

A South American amphibian could potentially hold the key to curing cirrhosis

December 6, 2017

The unique liver function of a South American amphibian, Siphonops annulatus, could pave the way to finding a cure to the devastating liver condition cirrhosis, a new study published in the Journal of Anatomy reports.

Researchers from the University of Surrey (UK), the Federal University of São Paulo and the Butantan Institute in Brazil used an innovative 3D liver cell examination to explore the liver function of this snake-like amphibian. During an in-depth examination, it was found that the liver of Siphonops annulatus produces blood cells throughout its lifetime and breaks down the protein collagen.

According to Dr Robson Gutierre, a morphologist and leading author of this study, the South American amphibian has very unique liver cells, known as melanomacrophages, which can remove and break down collagen as part of its natural function. In the same species, melanomacrophages also naturally engulf basophils, helping to minimise unwanted inflammation and reduce the scar tissue which can lead to cirrhosis.

Cirrhosis occurs in response to damage to the liver. Chronic alcoholism, hepatitis or other harmful substances can promote the response of self-repair in the liver, mainly represented as a high production of collagen and scar formation (fibrosis). As cirrhosis progresses, liver functions such as detoxification and cleaning of blood, among others, become difficult.

Several treatment strategies for cirrhosis have been tried throughout the world, such as delaying or removing the underlying stimulus that causes scars to form. Other treatments have looked at the degradation and/or removal of collagen.

Co-author Dr Augusto Coppi, lecturer in Veterinary Anatomy and Stereologist at the University of Surrey, said: “The liver function of this amphibian, Siphonops annulatus, may provide us with a unique opportunity to solve one of the most devastating illnesses of the liver.

“We do need further in-depth investigations into how this discovery could be translated into humans, but it may have the potential to alter how we view and treat this disease. We are constantly amazed by nature, and this particular and not-well-studied species of amphibian could help us find a way to stop or even reverse liver cirrhosis.”

Dr Robson Gutierre from the Federal University of São Paulo said: “The ability this species has to break down its natural defences could also provide insight into immunity tolerance, a mechanism by which the liver can minimise unwanted inflammations. Immunity tolerance can be studied in this species because they produce pro-inflammatory cells in the hematopoietic liver throughout its whole life, without developing chronic inflammations.”

Liver cirrhosis must be diagnosed early and the cause treated, but damage is rarely reversed. In the late stages, cirrhosis is life threatening. Every year more than 4,000 people in the UK die from cirrhosis and an estimated 700 people have to have a liver transplant each year to survive.

Researchers will continue to explore how this could be translated into humans.

Amphibian research with glow sticks


This video from the USA says about itself:

5 August 2013

Eastern (Red-Spotted) Newt

Did You Know?

•The eastern (red-spotted) newt is a widespread and native salamander of New York State and eastern North America that can live for 12-15 years!
•Adults and larvae use gills to breathe and live in water; however, juveniles (also known as “efts”), become land dwellers and develop lungs to breathe air.
•The eastern (red-spotted) newt secretes poisonous toxins, and the eft’s bright coloration serves as a warning to predators.
•Eastern newts use specialized chemicals to find food and attract mates.
•They help reduce mosquito populations by feeding on their larvae.

From Penn State university in the USA:

Use of glow sticks in traps greatly increases amphibian captures in study

November 7, 2017

With amphibian populations declining around the world and funds to find the causes scarce, a team of Penn State researchers has shown that an unorthodox tactic will make it easier and therefore less expensive to capture adult salamanders and frogs.

The researchers demonstrated that glow sticks — cheap, self-contained, short-term light-sources — attract the creatures to traps set in vernal pools where they come to reproduce in the spring. The translucent plastic tubes contain isolated substances that, when combined, make light through chemiluminescence.

Often used for recreation, glow sticks are sometimes relied upon for light during military, police, fire or emergency operations. However, they have not been widely used in wildlife research and their appeal to amphibians is not well understood, according to David Miller, assistant professor of wildlife population ecology, College of Agricultural Sciences.

“This work is important because research funding is often limited, especially when we’re talking about amphibians and reptiles compared to mammals or other charismatic species,” he said. “With a warming climate, monitoring data will become only more important for informing conservation decisions. If we can find a way to improve our capture rate, it is going to mean less time, effort and expense to study amphibians.”

As part of a long-term national study, Miller’s lab has been monitoring amphibian populations at sites around Pennsylvania. Spearheading that effort has been David Munoz, doctoral degree candidate in ecology, who helped create the Salamander Population Adaptation Research Collaboration Network, or SPARCnet. It was his idea to “bait” traps with glow sticks at one site as an experiment. The researchers chose State Game Land 176 in Centre County, managed by the Pennsylvania Game Commission. The research using glow sticks took place in a forested area known as the Scotia Barrens, which contains a dense network of vernal pools where Miller’s lab has been monitoring amphibian populations for years.

Within this network, researchers surveyed 12 pools, varying in size but with similar habitat characteristics — no aquatic vegetation and leaf-litter bottoms. Each pool dries mid- to late-summer in most years. Surveys for this experiment were conducted in March and April 2015, and traps were continuously deployed during surveys.

Over the course of nine trapping nights, researchers captured 4,935 amphibians. Glow sticks increased the average number of captures of spotted salamanders by more than three times, Jefferson salamanders by nearly four times, wood frogs by almost three times and Eastern newts by as much as six times, compared to control traps.

The research, which was published in Herpetological Review, focused on adult amphibians, noted lead researcher Michael Antonishak, an undergraduate majoring in wildlife and fisheries science when the study was done. He worked closely with Munoz on the project.

Past studies found that baiting traps with glow sticks increased the capture rates of larval amphibians two to eight times compared to funnel traps with no lure, but no studies have tested the effectiveness of glow-stick lures on the capture rates of adult, vernal pool-breeding amphibians, Antonishak pointed out.

“We specifically focus on the adult stage of amphibians because life history suggests adults play the most critical role in population persistence,” he said. “Capturing adults also make techniques such as mark-recapture feasible, providing estimates of abundance and survival to improve conservation decisions.”

Why are glow sticks effective lures for capturing amphibians? Researchers are not sure, Munoz admitted. It is likely a straightforward visual cue, but it could be more than that.

It is generally accepted that amphibians do not eat while they are breeding but it is possible that the light actually attracts different organisms that the amphibians may eat — perhaps the amphibians are gravitating toward those species, he explained.

“Without actually testing that, we can’t say for sure,” Antonishak added. “Are they attracted to the light itself or is it possible that the amphibians just see a little better in the pool where glow sticks are illuminating the water? Perhaps females, for instance, see males a little better and they are more attracted to them.”

What a prehistoric salamander ate


Phosphotriton sigei

This picture shows a three-dimensional reconstruction of the skeleton of Phosphotriton sigei gen. et sp. nov. (B), scaled to the same length as other Eurasian urodeles: a European plethodontid, Hydromantes italicus Dunn, 1923 (A), and two salamandrids, Hypselotriton orientalis (David, 1873) (C) and Salamandra salamandra (Linnaeus, 1758) (D).

From ScienceDaily:

Ancient petrified salamander reveals its last meal

Researchers identify frog bones within the stomach of a 35 million year old ‘mummified’ salamander fossil using advanced x-ray imaging techniques. At least six kinds of organs are preserved in almost perfect condition

October 3, 2017

A new study on an exceptionally preserved salamander from the Eocene of France reveals that its soft organs are conserved under its skin and bones. Organs preserved in three dimensions include the lung, nerves, gut, and within it, the last meal of the animal, according to a study published in the peer-reviewed journal PeerJ by a team of palaeontologists from France and Switzerland.

Accessing the complete anatomy of an extinct animal, i.e. both its external and internal aspects, has often been the dream of palaeontologists. Indeed, in 99% of cases, fossils are only represented by hard parts: bones, shells, etc. Fossils preserving soft tissues exist, but they are extremely rare. However, their significance for science is enormous. What did the animal look like? What did they eat? How did they live? Most of these questions can be answered by exceptionally preserved fossils.

The newly studied fossil externally looks like a present-day salamander, but it is made of stone. This fossil “mummy” is the only known specimen of Phosphotriton sigei, a 40-35 million years old salamander and belongs to the same family as the famous living fire salamander (Salamandra salamandra).

It is unfortunately incomplete: only the trunk, hip and part of hind legs and tail are preserved. Until very recently, the only thing palaeontologists could tell about this specimen was visible anatomical details, such as the cloaca, the orifice used for reproduction and by digestive and urinary canals. Indeed, though it was discovered in the 1870s, it was never studied in detail.

Thanks to recent synchrotron technology, its skeleton and various organs could be studied. The specimen was scanned at the ID19 beamline of the European Synchrotron Radiation Facility (ESRF) in Grenoble (France). This modern technology gave access to an incredible level of details that could never have been achieved before without slicing the specimen into a series of thin sections.

The quality of preservation is such that looking at the tomograms (equivalent of radiograms) feels like going through an animal in the flesh. At least six kinds of organs are preserved in almost perfect condition, in addition to the skin and skeleton: muscles, lung, spinal cord, digestive tract, nerves, and glands.

But the most incredible is the preservation of frog bones within the stomach of the salamander. Salamanders almost never eat frogs or other salamanders, though they are known to be quite opportunistic. Was it a last resort meal or a customary choice for this species? This, unfortunately, will probably never be known.

These new results are described by Jérémy Tissier from the Jurassica Museum and the University of Fribourg in Switzerland, and Jean-Claud Rage and Michel Laurin, both from the CNRS/Museum national d’histoire naturelle/UPMC in Paris.

Author Michel Laurin notes, “This fossil, along with a few others from the same lost site, is the most incredibly well-preserved that I have seen in my entire career. And now, 140 years after its discovery, and 35 million years after the animal died, we can finally study it, thanks to modern technology. The mummy returns!”