Dugong ancestor discovery in Panama


About 19-21 million years old, this dugong is the oldest marine mammal found in Central America and the first from the Pacific side of the Panama Canal. Here, the skull is seen from the side with the snout pointing to the right. Credit: Jeff Gage, Florida Museum

From the Florida Museum of Natural History in the USA:

20-million-year-old tusked sea cow is Central America’s oldest marine mammal

February 19, 2019

Summary: A researcher searching the shoreline of the Panama Canal for fossil plants instead found an ancient sea cow. An ’emergency fossil excavation’ due to rising water levels yielded a remarkably complete skeleton of a new genus and species of dugong, estimated to be about 20 million years old, the first evidence of a marine mammal from the Pacific side of the canal.

Steven Manchester didn’t set out to discover Central America’s oldest known marine mammal. He was hoping to find fossil plants.

Manchester, curator of paleobotany at the Florida Museum of Natural History, had left a group of vertebrate paleontologists uphill of the Panama Canal to do his own prospecting, clambering down onto the narrow, exposed shoreline to look for fossil leaves, petrified wood and mineralized fruits and nuts.

It was a dangerous place to be: The rolling wake from passing ships could sweep a person off shore and into the canal. Manchester noticed that people were occasionally shouting at him through megaphones as they cruised past, but not understanding Spanish, he continued to comb the shore when he spotted bone.

“He quickly walked us over to where he’d found a skeleton sticking out of the rock exposure,” said Aaron Wood, then a museum postdoctoral researcher leading fieldwork in Panama. “There were two or three vertebrae, orange-ish in color, dipping into the black rock on the side of the canal and a couple of ribs around them. We guessed that there would be more under the rock.”

What Wood described as an “emergency fossil excavation” due to rising water levels yielded a remarkably complete skeleton of an ancient sea cow, estimated to be about 20 million years old, the first evidence of a marine mammal from the Pacific side of the canal.

The fossil skull, vertebrae, ribs and other bones belong to a new genus and species, Culebratherium alemani, a tusked seagrass-grazing relative of modern dugongs, which live in the warm coastal waters of the Indo-Pacific.

Wood and lead author Jorge Velez-Juarbe, also a former museum postdoctoral researcher, published their findings in the Journal of Vertebrate Paleontology.

About 15 feet long, this C. alemani was not done growing, Velez-Juarbe said. Its tusks had only begun to protrude and its newest molars showed little wear, indicating it was not yet an adult.

But it was a powerful eater. The researchers propose that its thick neck muscles, tusks and downward-pointing snout were adaptations for digging pits in the ocean floor to get to the underground stems of seagrass, the plants’ most nutritional parts.

“Finding C. alemani is pretty good evidence that there was seagrass in this region 20 million years ago,” said Velez-Juarbe, now assistant curator of marine mammals at the Natural History Museum of Los Angeles County. “This particular group of sirenians” — the order that includes dugongs and manatees — “are seagrass specialists.”

While only one species of dugong is alive today — a second, Steller’s sea cow, was hunted to extinction within 27 years of its discovery — about 30 species have been recovered in the fossil record, Velez-Juarbe said. The group originated in the West Atlantic and Caribbean and dispersed westward through Panama, whose seaway did not close until a few million years ago, and south to Brazil.

“Today, Panama is the juncture between two continents, and that’s where we have a mixture of mammals between North and South America,” said Wood, now director of Iowa State University’s Carl F. Vondra Geology Field Station and a lecturer in the department of geological and atmospheric sciences. “In the early Miocene, when this dugong lived, it wasn’t a land connection but a sea connection between the Atlantic and Pacific. We would expect to see communities of sea cows there, too.”

Previous research shows that multiple species of dugongs commonly lived together, each with slightly differently shaped tusks, snouts and body sizes that would have enabled them to divide up food resources, Velez-Juarbe said.

“Some would eat larger species of seagrass buried deeply in the sand while others would feed on smaller grasses closer to the surface,” he said. “Evidence from many other places in the world shows that multispecies communities were the norm. To only have one species of dugong now is freaky.”

These communities also made for healthier seagrass beds, he said. Whereas a single seagrass species, Thalassia testudinum, dominates the Caribbean and West Atlantic, grass beds in Australia have a better balance of species because modern dugongs feed on the larger grass species, keeping them in check and giving smaller grasses a shot at flourishing.

The researchers named C. alemani after the Culebra Formation where it was found and Alberto Aleman Zubieta, the former chief executive officer of the Panama Canal, whose support they described as essential to the fieldwork’s success.

C. alemani was excavated as part of a large-scale, years-long project to salvage fossils during the expansion of the Panama Canal, which temporarily exposed fresh outcrops. Wood said that while he and the rest of the field crew understood the significance of their work, the discovery of the dugong “really brought that home”.

“We found the fossil dugong when water levels were at their lowest,” he said. “After the first day, they steadily rose. We put sandbags on the edge of the site just to keep water out long enough for us to collect it. Within a week, the site was flooded. We couldn’t go back. The idea that this was a once-in-a-century opportunity was wrapped up in this one specimen.”

The researchers began the work as postdoctoral fellows under the advisership of Jonathan Bloch and Bruce MacFadden, Florida Museum curators of vertebrate paleontology.

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Marsupial lived among Alaskan dinosaurs


This 15 February 2019 video says about itself:

An animation of a fossilized jaw belonging to Unnuakomys hutchisoni, an ancient marsupial that lived in what is now the North Slope of Alaska.

From the University of Alaska Fairbanks:

Marsupial lived among Arctic dinosaurs

February 19, 2019

A research team has discovered a previously unknown species of marsupial that lived in Alaska’s Arctic during the era of dinosaurs, adding a vivid new detail to a complex ancient landscape.

The thumb-sized animal, named Unnuakomys hutchisoni, lived in the Arctic about 69 million years ago during the late Cretaceous Period. Its discovery, led by scientists from the University of Colorado and University of Alaska Fairbanks, is outlined in an article published in the Journal of Systematic Palaeontology.

The discovery adds to the picture of an environment that scientists say was surprisingly diverse. The tiny animal, which is the northernmost marsupial ever discovered, lived among a unique variety of dinosaurs, plants and other animals.

Alaska’s North Slope, which was at about 80 degrees north latitude when U. hutchisoni lived there, was once thought to be a barren environment during the late Cretaceous. That perception has gradually changed since dinosaurs were discovered along the Colville River in the 1980s, with new evidence showing the region was home to a diverse collection of unique species that didn’t exist anywhere else.

Finding a new marsupial species in the far north adds a new layer to that evolving view, said Patrick Druckenmiller, the director of the University of Alaska Museum of the North.

“Northern Alaska was not only inhabited by a wide variety of dinosaurs, but in fact we’re finding there were also new species of mammals that helped to fill out the ecology,” said Druckenmiller, who has studied dinosaurs in the region for more than a decade. “With every new species, we paint a new picture of this ancient polar landscape.”

Marsupials are a type of mammal that carries underdeveloped offspring in a pouch. Kangaroos and koalas are the best-known modern marsupials. Ancient relatives were much smaller during the late Cretaceous, Druckenmiller said. Unnuakomys hutchisoni was probably more like a tiny opossum, feeding on insects and plants while surviving in darkness for as many as four months each winter.

The research team, whose project was funded with a National Science Foundation grant, identified the new marsupial using a painstaking process. With the help of numerous graduate and undergraduate students, they collected, washed and screened ancient river sediment collected on the North Slope and then carefully inspected it under a microscope. Over many years, they were able to locate numerous fossilized teeth roughly the size of a grain of sand.

“I liken it to searching for proverbial needles in haystacks — more rocks than fossils,” said Florida State University paleobiologist Gregory Erickson, who contributed to the paper.

Jaelyn Eberle, curator of fossil vertebrates at the University of Colorado Museum of Natural History, led the effort to examine those teeth and a few tiny jawbones. Their analysis revealed a new species and genus of marsupial.

Mammal teeth have unique cusps that differ from species to species, making them a bit like fingerprints for long-dead organisms, said Eberle, the lead author of the study.

“If I were to go down to the Denver Zoo and crank open the mouth of a lion and look in — which I don’t recommend — I could tell you its genus and probably its species based only on its cheek teeth,” Eberle said.

The name Unnuakomys hutchisoni combines the Iñupiaq word for “night” and the Greek word “mys” for mouse, a reference to the dark winters the animal endured, and a tribute to J. Howard Hutchison, a paleontologist who discovered the fossil-rich site where its teeth were eventually found.

Other co-authors of the Journal of Systematic Palaeontology paper include William Clemens, of the University of California, Berkeley; Paul McCarthy, of UAF; and Anthony Fiorillo, of the Perot Museum of Nature and Science.

Dutch Afghan war veterans’ health problems


Burn pit in Afghanistan, photo Dutch Ministry of Defence

Translated from Dutch NOS TV today:

Within two weeks, 110 soldiers have already reported that they have become ill through so-called burn pits or are worried about them. Burn pits are pits that were used to burn waste in mission areas in Afghanistan.

There was unrest among soldiers sent out after colleagues reported health complaints that might be related to those burn pits. Initially, Minister Bijleveld [of war, sorry I am supposed to say Defense] said that no one had reported to the Ministry of Defense, but later it turned out that soldiers had indeed expressed their concerns, eg, to military physicians. These, however, were not considered official reports.

Bijleveld then set up a hotline that started on 4 February. In the meantime 110 people have registered there. If the reports give reason to do so, the minister wants to independently investigate the health complaints, and will let the House of Representatives know. She wants to make a decision in April.

Cancer

In the burn pits, waste was burned in the open air. Soldiers claim that they have contracted cancer or other diseases as a result of the harmful substances released.

In her letter, Bijleveld writes that it is not uncommon to process waste in this way in mission areas. Often it is the only way to get rid of waste. The local population also does it.

In George W Bush’s ‘new’ Afghanistan, very many people are hungry and poor. They have no money to get rid of waste in more environmentally and medically sound ways. They as well may be suffering from the diseases caused by burn pits.

See also here.

Great white shark genome decoded


This 18 February 2019 video says about itself:

Scientists claim SHARK DNA could contain the secret to longer life in humans

Great white sharks may prove unlikely saviours of human lives thanks to their huge and extraordinary genome, scientists have discovered. The first “map” of the creature’s DNA has uncovered a plethora of mutations that protect against cancer and other age-related diseases, as well as enhanced wound healing.

Experts believe understanding more about the way the great white has evolved to keep its genome stable and resist disease could lead to new life-preserving human treatments. Study co-leader Dr Mahmood Shivji, director of the Save Our Seas Foundation Shark Research Centre at Nova Southeastern University in Florida, US, said: “Genome instability is a very important issue in many serious human diseases. “Now we find that nature has developed clever strategies to maintain the stability of genomes in these large-bodied, long-lived sharks. “There’s still tons to be learned from these evolutionary marvels, including information that will potentially be useful to fight cancer and age-related diseases, and improve wound healing treatments in humans, as we uncover how these animals do it.” Cracking the great white genetic code also revealed the large size of the apex predator’s genome. It contains an estimated 4.63 billion “base pairs”, the chemical units of DNA, making it one-and-a-half times bigger than its human counterpart.

From Nova Southeastern University in the USA:

Great white shark genome decoded

Huge genome reveals sequence adaptations in key wound healing and genome stability genes tied to cancer protection

February 18, 2019

Summary: In a major scientific step to understand the biology of this iconic apex predator and sharks in general, the entire genome of the white shark has now been decoded in detail.

The great white shark is one of the most recognized marine creatures on Earth, generating widespread public fascination and media attention, including spawning one of the most successful movies in Hollywood history. This shark possesses notable characteristics, including its massive size (up to 20 feet and 7,000 pounds) and diving to nearly 4,000 foot depths. Great whites are also a big conservation concern given their relatively low numbers in the world’s oceans.

In a major scientific step to understand the biology of this iconic apex predator and sharks in general, the entire genome of the white shark has now been decoded in detail.

A team led by scientists from Nova Southeastern University’s (NSU) Save Our Seas Foundation Shark Research Center and Guy Harvey Research Institute (GHRI), Cornell University College of Veterinary Medicine, and Monterey Bay Aquarium, completed the white shark genome and compared it to genomes from a variety of other vertebrates, including the giant whale shark and humans.

The findings are reported in the ‘Latest Articles’ section of the journal Proceedings of the National Academy of Sciences.

Decoding the white shark’s genome revealed not only its huge size — one-and-a-half times the size of the human genome — but also a plethora of genetic changes that could be behind the evolutionary success of large-bodied and long-lived sharks.

The researchers found striking occurrences of specific DNA sequence changes indicating molecular adaptation (also known as positive selection) in numerous genes with important roles in maintaining genome stability ¬¬- the genetic defense mechanisms that counteract the accumulation of damage to a species’ DNA, thereby preserving the integrity of the genome.

These adaptive sequence changes were found in genes intimately tied to DNA repair, DNA damage response, and DNA damage tolerance, among other genes. The opposite phenomenon, genome instability, which results from accumulated DNA damage, is well known to predispose humans to numerous cancers and age-related diseases.

“Not only were there a surprisingly high number of genome stability genes that contained these adaptive changes, but there was also an enrichment of several of these genes, highlighting the importance of this genetic fine-tuning in the white shark,” said Mahmood Shivji, Ph.D., director of NSU’s Save Our Seas Foundation Shark Research Center and GHRI. Shivji co-led the study with Michael Stanhope, Ph.D., of Cornell University College of Veterinary Medicine.

Also notable was that the white shark genome contained a very high number of “jumping genes” or transposons, and in this case a specific type, known as LINEs. In fact this is one of the highest proportions of LINEs (nearly 30%) discovered in vertebrates so far.

“These LINEs are known to cause genome instability by creating double stranded breaks in DNA,” said Stanhope. “It’s plausible that this proliferation of LINEs in the white shark genome could represent a strong selective agent for the evolution of efficient DNA repair mechanisms, and is reflected in the positive selection and enrichment of so many genome stability genes.”

The international research team, which also included scientists from California State University, Monterey Bay, Clemson University, University of Porto, Portugal, and the Theodosius Dobzhansky Center for Genome Bioinformatics, Russia, also found that many of the same genome stability genes in the white shark were also under positive selection and enriched in the huge-bodied, long-lived whale shark.

The discovery that the whale shark also had these key genome stability adaptations was significant because theoretically, the risk of developing cancer should increase with both the number of cells (large bodies) and an organism’s lifespan — there is statistical support for a positive relationship of body size and cancer risk within a species. Interestingly, this does not tend to hold up across species.

Contrary to expectations, very large-bodied animals do not get cancer more often than humans, suggesting they have evolved superior cancer-protective abilities. The genetic innovations discovered in genome stability genes in the white and whale shark could be adaptations facilitating the evolution of their large bodies and long lifespans.

“Decoding the white shark genome is providing science with a new set of keys to unlock lingering mysteries about these feared and misunderstood predators — why sharks have thrived for some 500 million years, longer than almost any vertebrate on earth” said Dr. Salvador Jorgensen, a Senior Research Scientist at the Monterey Bay Aquarium, who co-authored the study.

But the innovations did not end there.

The shark genomes revealed other intriguing evolutionary adaptations in genes linked to wound healing pathways. Sharks are known for their impressively rapid wound healing.

“We found positive selection and gene content enrichments involving several genes tied to some of the most fundamental pathways in wound healing, including in a key blood clotting gene,” said Stanhope. “These adaptations involving wound healing genes may underlie the vaunted ability of sharks to heal efficiently from even large wounds.”

The researchers say they have just explored the “tip of the iceberg” with respect to the white shark genome.

“Genome instability is a very important issue in many serious human diseases; now we find that nature has developed clever strategies to maintain the stability of genomes in these large-bodied, long-lived sharks,” said Shivji. “There’s still tons to be learned from these evolutionary marvels, including information that will potentially be useful to fight cancer and age-related diseases, and improve wound healing treatments in humans, as we uncover how these animals do it.”

Decoding the white shark genome will also assist with the conservation of this and related sharks, many of which have rapidly declining populations due to overfishing,” said Steven O’Brien, a conservation geneticist at NSU, who co-conceived this study. “The genome data will be a great asset for understanding white shark population dynamics to better conserve this amazing species that has captured the imagination of so many.”

This research was funded by NSU’s Save Our Seas Foundation, the Guy Harvey Ocean Foundation, the Hai Stiftung/Shark Foundation, the Monterey Bay Aquarium, and in-kind support from Illumina, Inc., and Dovetail Genomics.

How click beetles move, new study


This 2013 video from the USA says about itself:

Eyed click beetle (Alaus oculatus) – This beetle belongs in the circus

My friend Bill and I were out looking for invertebrates and we found this guy under a log. It is a very large click beetle. The time of year is mid May. This is shot with my brand new sony cybershot DSC-wx150 so I finally got to try some test footage shooting in MP4.

From the University of Illinois College of Engineering in the USA:

Hinge morphology of click beetles‘ latch mechanism

February 18, 2019

Aimy Wissa, assistant professor of mechanical science and engineering (MechSE) at Illinois, leads an interdisciplinary research team to study click beetles to inspire more agile robots. The team, which includes MechSE Assistant Professor Alison Dunn and Dr. Marianne Alleyne, a research scientist in the Department of Entomology, recently presented their ongoing and novel work on the quick release mechanism of click beetles at the 2019 Society for Integrative and Comparative Biology (SICB) Annual Meeting.

Ophelia Bolmin, a graduate student in Wissa’s Bio-inspired Adaptive Morphology (BAM) Lab, presented novel synchrotron X-ray footage that showed the internal latch mechanism of the click beetle, and demonstrated for the first time to the scientific community how the hinge morphology and mechanics enable this unique clicking mechanism. The presentation, “The click beetle latch mechanism: An in-vivo study using synchrotron X-rays,” was part of an invited symposium on mechanisms of energy flow in organismal movement.

This work builds on research that was initiated by the Illinois team nearly two years ago, detailing the click beetles’ legless self-righting jumping mechanism. The team already built prototypes of a hinge-like spring-loaded device that are being incorporated into a robot.

Rather minimal research had been performed on the click beetle’s click mechanism in the past, and the Illinois team is the first to explore the insect within the field of bio-inspiration — using inspiration from nature for innovative engineered designs. They continue to be at the forefront of this research, and further studies are scheduled to be published in coming months.

New aloe species discovery in Somaliland


This 14 February 2019 video is called Aloe sanginalis, a new red Aloe from Somaliland.

From ScienceDaily:

Aloe sanguinalis, a new red Aloe from Somaliland

February 14, 2019

Aloe sanguinalis, or Somali Red Aloe, forms large, conspicuous clumps and has blood red sap. Its can easily be spotted from the road, but the species has only just been named and described in the open access journal PhytoKeys.

It remains a mystery how this beautiful and showy aloe species has remained undescribed by science for so long, but one of the theory is that the plant was ‘hiding in plain sight”‘ in an area not usually known for its hight biological diversity.

The locals in the area have long known that the plants were different from other kinds of “Dacar”, (the Somali name for Aloes) in the region and were referring to them as “Dacar cas” or “Red aloe.”

Similarly, the scientific name for the new species — Aloe sanguinalis — is based on one of its most distinct characters, its bright red color, coming from the peculiar blood-red sap the plant produces. The leaves also become reddish as they mature.

The story of the formal recognition of “Dacar cas” or Aloe sanguinalis, however, began when Ahmed Awale, a leading Somaliland environmentalist, spotted the large, reddish clumps plants, while driving through the country on behalf of Candlelight, an NGO focused on the environment, education, and health.

Later on, when the plant came to the attention of Mary Barkworth, a botanist interested in building botanical capacity in Somaliland. After listening to Ahmed, the two of them began looking formally into the possibility that “Dacar cas” was, indeed, an undescribed species. They were soon convinced it was. After the initial excitement, the next step required demonstrating that “Dacar Cas” differs from all the other 600+ known species of Aloe. That step took longer, but finally it has been done.

“This news comes from a region which had experienced periods of conflict and instability, climate change effects and accelerated environmental degradation, whereby much of the people’s attention has been focused on promoting livelihoods and resilience. With this positive piece of information we hope that we inspire scientists to further explore the area,” explains Dr Barkworth.

The new species is currently known from only two locations, but it is hoped that naming and sharing pictures of it online will encourage discovery and documentation of additional locations.

Red crossbill biology


This 2015 video from Canada is called Red Crossbills Singing and Feeding.

From the Cornell Lab of Ornithology in the USA:

A Bird Like No Other

Red Crossbills are endlessly fascinating: they have a can opener for a beak, they “speak” at least 10 different dialects, and they sometimes abruptly leave their home forests to travel hundreds of miles away. In a newly revised Birds of North America account, crossbill experts compile decades of first-hand knowledge to present an authoritative picture of this captivating bird—including first-of-their kind maps of call types and irruption movements that were a decade in the making.

Explore Red Crossbill biology in depth with free access all month to this groundbreaking Birds of North America account.