Drone gull counts birds


This August 2016 video from the Netherlands shows a drone shaped like a herring gull. Its name is Kobus. It counts birds. Gulls don’t scare other birds, contrary to, eg, eagles.

In this video, Kobus counts birds at the Naardermeer nature reserve.

West African lions are different, new research


This video says about itself:

West African lion – Video Learning – WizScience.com

24 September 2015

The “West African lion” , also known as the “Senegal lion”, is a lion subspecies native to western Africa. Results of genetic research indicate that the Western and Central African lions form a different clade of lions and are perhaps more related to Asian lions than to lions from southern or eastern Africa. The genetic distinctiveness is particular of interest, since lions are regionally endangered in western Africa. With a total population of perhaps less than 1,000 individuals in all of West and Central Africa and no captive population, the West African lion is one of the most endangered subspecies of big cats.

Lions from western and central Africa are believed to be smaller than lions from southern Africa. It is also suggested that they have smaller manes, live in smaller groups, and they may also differ in the shape of their skull.

In the Pendjari National Park area, which is within the range of the West African lion, almost all males are maneless or have very weak manes.

The West African lion is distributed in western Africa south of the Sahara from Senegal in the west to the Central African Republic in the east. Another subspecies or North East Congo lion is traditionally described from northeastern Democratic Republic of the Congo.

Lions are rare in western Africa and may be critically endangered in this region. In 2004 there were probably only 450-1,300 lions left in West Africa. In addition, there were about 550-1,550 in Central Africa. In both regions, the area inhabited by lions has been reduced until 2004 to less than 15% of the historic range.

From Leiden University in the Netherlands:

Lions in West and Central Africa apparently unique

10 August 2016

Lions in West and Central Africa form a unique group, only distantly related to lions in East and Southern Africa. Biologists at Leiden University confirm this in an article published in Scientific Reports.

Genetic data

In this study, the researchers gathered a genetic dataset of lion populations covering a total of 22 countries. This included samples from each remaining lion population in West and Central Africa, a region where lions and other wildlife are rapidly declining as a consequence of the increasing human population. The researchers managed to gather all the information by teaming up with other people in the field and local conservationists.

300,000 years ago

Based on the genetic data, it was estimated that the split between the two major groups that can be identified in the lion must have occurred 300,000 years ago. To explain what happened in their evolution, the researchers made a reconstruction of African climatological history. It seems that periodic expansions of the rain forest and the desert drove lions into isolated pockets of suitable habitat, where the different genetic lineages originated that can still be observed today.

Other mammals

This influenced not only the patterns we observe in the lion, but also in other large mammals such as giraffe, buffalo, hartebeest, cheetah and spotted hyena. A general pattern is emerging that shows that many large African savannah mammals show very similar arrangements, with unique lineages in West and Central Africa.

Reason for concern

The strong declines in wildlife populations in large parts of West and Central Africa are therefore a reason for major concern. The fact that this region seems to harbour a lot of unique genetic lineages makes conservation in the area extremely important. A delegation from Leiden University will participate in the IUCN World Conservation Congress in September 2016, and will lead a Side Event that aims to establish a Species Action Plan for West and Central Africa. The researchers hope that this will facilitate coordination and funding of projects in the region.

Warbler birds in Maine, USA


This video from the USA says about itself:

Black-throated green warblers are a very common breeding species in Maine. They can be found in a variety of habitat but prefer mixed deciduous forests. Their buzzy song is often one of the first warbler songs I hear in the spring. © 2012 Garth McElroy.

From the Cornell Lab of Ornithology in the USA:

The Changing Cast of Maine‘s Famous Spruce-Woods Warblers

The magical songs of warblers have echoed through the Maine woods for millennia. In the 1950s, noted ecologist Robert MacArthur made these warblers famous by studying how different species can live together by using different foraging areas within the same tree. Now, 60 years later, a researcher revisits the spot to see what has changed and what has stayed the same. Read the story and listen to the calls.

BE RIGHT BACK, ROAD-TRIPPING TO THE NEW NATIONAL PARK The tens of thousands of acres of Maine forest previously owned by one of the co-founders of Burt’s Bees are now federally protected — just in time for the 100-year celebration of the National Park Service today. [Hilary Hanson, HuffPost]

New frog species discovery in Peru


Sleeping beauty rain frog, photo Germán Chávez

From Science, Space & Robots:

Newly Discovered Rain Frog Named After Sleeping Beauty Mountains

Posted on August 11, 2016

A new species of rain frog has been discovered in the premontane forests of the Peruvian central Andes. The frog has been named after the Sleeping Beauty mountains. This is the local name for the mountains where the frog lives. The Bella Durmiente (Sleeping beauty) mountain chain … is named for its resemblance to a sleeping woman.

The frog’s scientific name is Pristimantis pulchridormientes. “Pulcher” is Latin for beautiful and “dormientes” means sleeping. The common name for the new frog species is Sleeping beauty rain frog.

The frog has bright-red groins, shanks and thighs. It has a yellowish-brown body. The frog was discovered and described by Drs German Chavez, Centro de Ornitología y Biodiversidad (CORBIDI), and Alessandro Catenazzi, affiliated with both CORBIDI and Southern Illinois University.

Dr. Chavez says in the announcement, “When we heard the chorus of males, first thought was: such a strange call! When we saw this amazing frog, we knew that it is a new species. No other frog has that bright red colour on rear limbs!”

A research paper on the newly discovered frog species can be found here in the journal ZooKeys.

Greenland sharks may live 400 years


This video says about itself:

11 August 2016

Greenland sharks are the new record holders for longest-living vertebrates after a new study put their maximum lifespan at an incredible 400 years.

Learn more about this story here.

From Science magazine:

Greenland shark may live 400 years, smashing longevity record

By Elizabeth Pennisi

Aug. 11, 2016, 2:00 PM

Imagine having to wait a century to have sex. Such is the life of the Greenland shark—a 5-meter-long predator that may live more than 400 years, according to a new study, making it the longest lived vertebrate by at least a century. So it should come as no surprise that the females are not ready to reproduce until after they hit their 156th birthday.

The longevity of these sharks is “astonishing,” says Michael Oellermann, a cold-water physiologist at Loligo Systems in Viborg, Denmark, who was not involved with the work. That’s particularly true because oceans are quite dangerous places, he notes, where predators, food scarcity, and disease can strike at any time.

Greenland sharks (Somniosus microcephalus) had been rumored to be long-lived. In the 1930s, a fisheries biologist in Greenland tagged more than 400, only to discover that the sharks grow only about 1 centimeter a year—a sure sign that they’re in it for the long haul given how large they get. Yet scientists had been unable to figure out just how many years the sharks last.

Intrigued, marine biologist John Steffensen at the University of Copenhagen collected a piece of backbone from a Greenland shark captured in the North Atlantic, hoping it would have growth rings he could count to age the animal. He found none, so he consulted Jan Heinemeier, an expert in radiocarbon dating at Aarhus University in Denmark. Heinemeier suggested using the shark’s eye lenses instead. His aim was not to count growth rings, but instead to measure the various forms of carbon in the lenses, which can give clues to an animal’s age.

Then came the hard part. Steffensen and his graduate student Julius Nielsen spent several years collecting dead Greenland sharks, most of them accidently ensnared in trawling nets used to catch other types of fish. After that, they employed an unusual technique: They looked for high amounts of carbon-14, a heavy isotope left behind by nuclear bomb testing in the mid-1950s. Extra carbon from the resulting “bomb pulse” had infiltrated ocean ecosystems by the early 1960s, meaning that inert body parts formed during this time—in particular eye lenses—also have more of the heavy element. Using this technique, the researchers concluded that two of their sharks—both less than 2.2 meters long—were born after the 1960s. One other small shark was born right around 1963.

The team used these well-dated sharks as starting points for a growth curve that could estimate the ages of the other sharks based on their sizes. To do this, they started with the fact that newborn Greenland sharks are 42 centimeters long. They also relied on a technique researchers have long used to calculate the ages of sediments—say in an archaeological dig—based on both their radiocarbon dates and how far below the surface they happen to be. In this case, researchers correlated radiocarbon dates with shark length to calculate the age of their sharks. The oldest was 392 plus or minus 120 years, they report today in Science. That makes Greenland sharks the longest lived vertebrates on record by a huge margin; the next oldest is the bowhead whale, at 211 years old. And given the size of most pregnant females—close to 4 meters—they are at least 150 years old before they have young, the group estimates.

Oellermann is impressed not only with how old the sharks are, but also how Nielsen and his colleagues figured out their ages. “Who would have expected that nuclear bombs [one day] could help to determine the life span of marine sharks?” he asks.

He and others think cold water helps lengthen the animals’ lives by slowing down their growth and biochemical activity. “Lower metabolic rate plays a big role,” agrees Shawn Xu, a geneticist at the University of Michigan, Ann Arbor. “But that’s not the whole story.” Three years ago, his work in nematodes showed that cold can also activate antiaging genes that help an animal better fold proteins, get rid of DNA-damaging molecules, and even fight off infections more effectively, extending life span. The cold-activated molecules “are evolutionarily conserved” across the animal kingdom, and thus these pathways very likely exist in these sharks, too, he predicts.

Paul Butler isn’t surprised that frigid waters host such old creatures. In 2013, the sclerochronologist (a scientist who studies the growth of hard tissues in invertebrates) at Bangor University in the United Kingdom and his colleagues described a 500-year-old ocean quahog (Arctica islandica), a chowder clam found in the North Atlantic. Still, even though two multicentenarian species have turned up in the North Atlantic in just a few years, Butler is skeptical that there are many more out there awaiting discovery. “It won’t be that we won’t have more surprises,” he says, “but I regard these [two] as exceptions.”

Piltdown man hoax perpetrator exposed


This 2014 video is about the Piltdown man fraud.

From daily The Independent in Britain today:

Piltdown hoax: Culprit behind one of history’s greatest ruses finally exposed

Arthur Conan Doyle was even suspected of being the perpetrator

Kate Nelson

The culprit behind one of the greatest scientific hoaxes in history has been found after new forensic techniques revealed his identity.

Between 1912 and 1914, museum palaeontologist Arthur Smith Woodward and solicitor Charles Dawson claimed to have discovered fossils which supposedly showed the link between man and ape.

Known as the Piltdown Man, after the area of Sussex the remains were allegedly found, the discovery fooled even the most eminent scientific minds of the time.

It took more than 40 years to discover the hoax.

The new fossil had an ape-like jaw and brain-case like a modern human.

Mr Dawson claimed to have discovered further evidence at a second site, close to the original, prior to his death in August 1916.

Doubts were immediately raised but many thought the amateur archeologist was incapable of such a sophisticated ruse.

At one point Sir Arthur Conan Doyle, author of Sherlock Holmes, was under suspicion.

Some thought he wanted to mock scientists for ridiculing his spiritualist beliefs.

New research has now revealed that the forgeries were created using a limited number of specimens all constructed using a consistent method – suggesting the perpetrator acted alone.

It is highly likely that an orangutan specimen and at least two human skeletons were used to create the fakes, which are still kept at the Natural History Museum.

The work, which points the finger of suspicion firmly at Mr Dawson, was undertaken by a team led by Liverpool John Moores University and used the latest scientific methods.

Dr Isabelle De Groote, from the university and lead author on the paper which is published in Royal Society Open Science, said: “Although multiple individuals have been accused of producing the fake fossils, our analyses to understand the modus operandi show consistency between all the different specimens and on both sites.

“It is clear from our analysis that this work was likely all carried out by one forger – Charles Dawson.”

DNA analysis found that both the canine tooth planted at the first Piltdown site and the molar from the second probably came from one orangutan.

Holes in the skull bones were filled with dental putty, which was also used to re-set the teeth in the jaw and to reconstruct one of the teeth that fell apart while it was being ground down.

Chris Stringer, human origins expert at the Natural History Museum, said: “Our work shows that a century on, we can add a new chapter to the Piltdown story through new investigative techniques.

“We found surprising evidence that the forger had even removed the molars in order to modify them, and had then replaced them in the jawbone.”

Common ancestor of all wildlife, new research


This video says about itself:

Scientists Reveal LUCA – Common Ancestor Of All Living Things On Earth

26 July 2016

Many scientists believe that all living entities on Earth originated from an ancient organism called Luca which stands for the Last Universal Common Ancestor. Now, a team led by William F. Martin of Heinrich Heine University has released a new study which aims to “reconstruct the microbial ecology of LUCA.”

Many scientists believe that all living entities on Earth originated from an ancient organism called Luca which stands for the Last Universal Common Ancestor. The single-celled being likely lived around 4 billion years ago and is thought to have eventually spawned two distinct groups of uni-celled life–bacteria and archaea.

Now, a team led by William F. Martin of Heinrich Heine University has released a new study which aims to “reconstruct the microbial ecology of LUCA.” For the research, they tested 286,514 protein clusters and found that 355 protein families likely descended from the organism. Based on the attributes of this select group, the scientists theorize that Luca was able to withstand hot temperatures and live on hydrogen and carbon dioxide instead of oxygen; it also needed metals to be in the surrounding environment.

These combined attributes seem to indicate that this so-called universal ancestor lived in a habitat similar to a hot and gassy deep-sea vent. Despite the team’s findings, critics point out that additional information is needed to prove where life began.

From Nature Microbiology:

The physiology and habitat of the last universal common ancestor

Published online: 25 July 2016

Abstract

The concept of a last universal common ancestor of all cells (LUCA, or the progenote) is central to the study of early evolution and life’s origin, yet information about how and where LUCA lived is lacking.

We investigated all clusters and phylogenetic trees for 6.1 million protein coding genes from sequenced prokaryotic genomes in order to reconstruct the microbial ecology of LUCA. Among 286,514 protein clusters, we identified 355 protein families (∼0.1%) that trace to LUCA by phylogenetic criteria. Because these proteins are not universally distributed, they can shed light on LUCA’s physiology.

Their functions, properties and prosthetic groups depict LUCA as anaerobic, CO2-fixing, H2-dependent with a Wood–Ljungdahl pathway, N2-fixing and thermophilic. LUCA’s biochemistry was replete with FeS clusters and radical reaction mechanisms. Its cofactors reveal dependence upon transition metals, flavins, S-adenosyl methionine, coenzyme A, ferredoxin, molybdopterin, corrins and selenium. Its genetic code required nucleoside modifications and S-adenosyl methionine-dependent methylations. The 355 phylogenies identify clostridia and methanogens, whose modern lifestyles resemble that of LUCA, as basal among their respective domains.

LUCA inhabited a geochemically active environment rich in H2, CO2 and iron. The data support the theory of an autotrophic origin of life involving the Wood–Ljungdahl pathway in a hydrothermal setting.

See also here.