Meerkat family protects youngster from cobra


This video says about itself:

22 May 2018

Amazing Meerkat Family Protect Young Meerkat From Cobra Hunting

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Which European white storks will migrate to Africa?


This 2012 video from Germany is called White Stork on the nest (Ciconia ciconia).

From the Max-Planck-Gesellschaft in Germany:

Scientists can predict which storks will migrate to Africa in autumn and which will remain in Europe

May 24, 2018

For little Louis, it is the most exciting day of his life: just six or seven weeks ago, the young stork came into the world on a birch tree in Radolfzell on Lake Constance. Up to this day in June 2014, he has only known his parents and three siblings. But suddenly strange beings have appeared at the nest and are holding the four small white storks captive. They are Andrea Flack and Wolfgang Fiedler of the Max Planck Institute for Ornithology and the University of Konstanz. In the coming years, the scientists will learn from Louis and other young storks that, on their migrations south, storks follow other storks who are particularly good at exploiting thermals, allowing them to flap their wings as little as possible as they fly. The efficient fliers migrate to West Africa, while the others spend the winter in southern Europe. From their data, the researchers can tell which storks will fly where just ten minutes after the birds take off.

For days, Andrea Flack and Wolfgang Fiedler have been visiting storks’ nests on the western shore of Lake Constance. The aerial ladder of the fire brigade raises them to the stork nests at lofty heights so that they can strap small tracking devices onto the backs of the nestlings. The aim is to follow Louis and 60 other young storks on their migration. The instruments, which weigh less than 60 grams, record the GPS coordinates of the birds’ location. They also measure the animals’ movements using accelometers. This allows the researchers to determine whether and, if so, how the birds are moving.

For Louis and his nest mates, the harmless procedure is over in just a few minutes. Fully engaged in perfecting their flying skills, it is likely that they very soon forget the strange encounter with the scientists. For the researchers, however, the work has only just begun. From now on, they will collect and evaluate huge volumes of data, because the tracking devices log the storks’ GPS coordinates every second for two to five minutes every 15 minutes, and this for weeks. Once a day, the devices send a text message containing the location and movement data via the local mobile network, just like a mobile phone.

The data then flow automatically into an online database called Movebank, a free-to-use online platform developed by researchers led by Martin Wikelski, which allows scientists to log animal migrations anywhere in the world. Because the storks around Lake Constance fly all the way to West Africa for the winter, the mobile network costs would be enormous, given the immense volumes data involved. Andrea Flack therefore follows the birds by car all the way down to Barcelona to download the data once a day using a base station. In Africa, the devices log data at longer intervals to reduce the amount of data generated.

A mobile phone for storks

Louis, too, was fitted with his “mobile phone” on that day four years ago. As it turned out, he was the first among his nest mates to travel south. He joined a group of 27 other tagged storks. After five days of flying, 17 of them were still together.

Louis first skirted the Alps past Bern towards Lake Geneva and crossed the Rhone south of Lyon. On the evening of 23 August, he reached Montpellier on the French Mediterranean coast and then on the following day flew along the coast towards Spain. He crossed the Pyrenees and spent several weeks on a landfill site a hundred kilometres northwest of Barcelona. He then flew to an area around Madrid and spent the winter there at a landfill. He remained in Spain until the spring of 2016 and returned to Germany in March 2016.

Searching for thermals

Never before have researchers tracked a group flight of storks as meticulously as Louis and his peers. The scientists of the Max Planck Institute for Ornithology and the University of Konstanz have now published the results of Louis’ and his peers’ voyage. The data from the thousand-kilometre stage show how a bird’s flight performance, social behaviour and global migratory route are interlinked.

Thanks to a sophisticated analysis of the GPS data, the scientists have found that there are leader birds within groups of migrating storks. They lead the group to areas with favourable thermals, where the birds are literally sucked up by the rising warm air. This allows them to glide farther and avoid active flapping flight to save energy.

Efficient flyers lead the way

Detailed analysis of the high-resolution GPS data shows that the flight paths of the leader birds are more irregular. “They are the ones who locate the thermals and search out the most favourable areas within them. “As a result, they have to adjust their flight paths repeatedly”, explains Máté Nagy, who analyzed the data from the trackers. The follower birds benefit from the leaders’ explorations and can soar upward in more regular trajectories. “When travelling to the next thermal, follower birds are a bit slower and lose altitude faster. To avoid falling behind the group, they must flap their wings more and leave the thermals before reaching the top.”

However, a stork’s flying skill is not only linked to its position within the group. How much it flaps its wings also predicts where it will spend the winter. Animals that flap their wings a lot do not fly as far as those that flap less. Louis, for example, is a rather mediocre flyer. For him, it is better to spend the winter in southern Spain, especially since he can find enough food at the landfill site there.

Tour group with social structure

The situation is entirely different for Redrunner, another individual of the 27 tagged storks. He is one of the leaders of his group, and, therefore, manages to minimize his wing beats. He overwinters in North Africa. While Louis covered more than 1000 kilometres on his 2014 journey, Redrunner covered nearly 4000 kilometres. “The flight characteristics are so central to the birds’ position within the group that we can predict just after a few minutes of migration flight whether it will spend the winter in Europe or fly on to West Africa,” explains Andrea Flack.

This is the first time that humans have been able to observe the group behaviour of storks on their journey across Europe to Africa in such detail. The collected data show that storks fly in socially structured groups, which are largely determined by the flying skills of the group members. “A stork’s route and destination depend, among other things, on how efficiently it can fly,” says Martin Wikelski, Director at the Max Planck Institute for Ornithology and Honorary Professor at the University of Konstanz.

Back in Germany

Since then, Louis und Redrunner have repeated their journey every year — and always with the same destination: Louis has remained faithful to Spain and Redrunner to Africa. This year, Louis arrived in Germany on 9 March. Since then, he has stayed in Neudingen near Donaueschingen and has built a nest with a partner on the local town hall. Redrunner also returned from Africa a few weeks ago. He has taken up residence in the town of Münzenberg between Frankfurt and Giessen.

Now four years old, they have both survived the most dangerous phase of their lives, as 75 percent of young storks die in the first year. Now they are past puberty and may breed this year for the first time. If the two storks continue to successfully avoid all dangers, it is likely they will have a long life and will continue to make their long journey for the next 30 years.

Assuming that the two are still migrating, the researchers will no longer have to follow them in a car. The Icarus Initiative launched by Martin Wikelski will be launched in August, after which the tracking devices will transmit their data to scientists around the world via the International Space Station. Researchers will then be able to track the birds around the clock in real time.

‘Cuckoo’ fish in Africa


This 2015 aquarium video is called A video of my Synodontis multipunctatus (cuckoo catfish) and my red empress spawning.

From the University of Konstanz in Germany:

Brood parasitism in fish

May 9, 2018

Summary: Biologists have demonstrated that ‘evolutionary experience’ as well as learning protects cichlid fish from the brood parasitism practiced by the African cuckoo catfish.

There are other animals besides the cuckoo who smuggle their offspring into another animal’s nest. The Synodontis multipunctatus, which occurs in Lake Tanganyika in Africa and is better known as cuckoo catfish, is just as cunning as the cuckoo is. Just like the bird, this savvy parasite manages to place its eggs among those of cichlids. To protect their eggs, cichlids carry them in their mouths. This can be fatal for the cichlids’ own offspring if cuckoo catfish eggs are among them. Professor Axel Meyer, an evolutionary biologist from the University of Konstanz, and a team of researchers from the Institute of Vertebrate Biology in Brno (Czech Republic) have carried out research into the evolutionary strategies employed by cuckoo catfish and various types of cichlids that occur in Lake Tanganyika and several other African lakes. Their study paints a fascinating picture of evolutionarily shaped and individually learned defence behaviour as well as the deception efforts employed by both species of fish — and the high price that cichlids pay for keeping the illegitimate offspring of the cuckoo catfish away from their own eggs. The research findings were published in the Science Advances issue published on 2 May 2018.

Lake Tanganyika in Africa is famous for its biodiversity. Many of its 250 endemic species of cichlids are mouthbreeders: To protect their offspring and prevent other fish from devouring it, cichlids carry and breed their eggs in their mouths. For several weeks after hatching and swimming by themselves, the young fish return to their mother’s mouth for protection.

It is this very particular brood care behaviour that the cuckoo catfish, also endemic to Lake Tanganyika, has learned to exploit: When the cichlids spawn, it simply places its own eggs among a cichlid’s clutch of eggs. If this goes unnoticed by the cichlid and if it cannot tell its own eggs apart from those of the catfish, it will carry and breed both its own and the catfish eggs in its mouth. However, the larvae of the cuckoo catfish hatch sooner, devouring the cichlid’s own offspring which the deceived mother cichlid believes to be safe. Often, the cichlid will believe the illegitimate offspring of the catfish to be her own even then, continuing to protect it.

But the cichlids are not entirely defenceless: They have learned to defend themselves against the cunning of the cuckoo catfish. When gathering their eggs into their mouth, they try to identify and exclude the smuggled eggs. Often, however, overcaution will lead them to reject some of their own eggs as well. A high price that the cichlids pay in return for their own “evolutionary fitness,” a price, however, they cannot avoid paying if their offspring is to survive.

“Evolutionary experience”

“Both species of fish have co-evolved for millions of years,” says Axel Meyer about their well-matched relationship of deception and defence. The behaviour of these two species is evidence of what the biologist calls “evolutionary experience”, which he was able to document in his joint study with his colleagues from Brno.

The scientists obtained eggs both from the cuckoo catfish and from the mouthbreeding cichlids that live in Lake Tanganyika and raised them in an aquarium. Then, they compared the captive cichlids’ capacity for distinguishing between their own eggs and those of the cuckoo catfish with that of other types of cichlid from other bodies of water where cuckoo catfish do not occur. The result: The deceptive strategy employed by the cuckoo catfish worked between three and eleven times better on the “evolutionarily naive” cichlids (from other bodies of water). Due to their “evolutionary experience,” the cichlids from Lake Tanganyika, who share an evolutionary history with the cuckoo catfish, were much more successful in identifying and rejecting the parasite’s eggs. By the term “evolutionary experience” the scientists mean natural selection in favour of the ability to discriminate smuggled eggs.

Individual learning works in co-evolved fish, but on “evolutionarily naïve” species

The study also revealed that cichlids lacking “evolutionary experience” are unable to learn to reject the eggs of the cuckoo catfish — in contrast to coevolved cichlids that increase their chances to see through the cuckoo catfish trick. This ability to adapt made the cichlids from Lake Tanganyika much more successful when coping with brood parasites. These findings suggest that is not the combination of “evolutionary experience” with individual experience and the ability to learn that help cichlids discriminate between their own and foreign eggs.

Unique among fish

Several bird species are known to practice brood parasitism, i.e. the smuggling of eggs into another bird’s nest. Among fish, the cuckoo catfish is the only known obligate brood parasite. None of the other 40 catfish species endemic to Lake Tanganyika are known to behave like this.

Saving forest elephants saves forests


This 2013 video says about itself:

The Dzanga Bai, a small clearing in the Central African Republic, is a unique haven for endangered forest elephants. As many as 200 at a time will gather in this open area to eat minerals found in the soil. The Bai is part of the protected Dzanga-Ndoki National Park, but poachers recently entered the park killing more than two dozen elephants. This video shows elephants enjoying the Bai and reveals efforts to again make it a safe haven for the African forest elephant, a species whose numbers have been reduced by more than 60% in the past decade.

From the Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign in the USA:

Protect forest elephants to conserve ecosystems, not DNA

April 25, 2018

Although it is erroneously treated as a subspecies, the dwindling African forest elephant is a genetically distinct species. New University of Illinois research has found that forest elephant populations across Central Africa are genetically quite similar to one another. Conserving this critically endangered species across its range is crucial to preserving local plant diversity in Central and West African Afrotropical forests — meaning conservationists could save many species by protecting one.

“Forest elephants are the heart of these ecosystems — without them, the system falls apart, and many other species are jeopardized”, said the principal investigator of this research, Alfred Roca, a professor of animal sciences at the Carl R. Woese Institute for Genomic Biology and College of Agricultural, Consumer and Environmental Sciences (ACES).

African forest elephants (Loxodonta cyclotis) are morphologically and genetically distinct from their iconic larger cousins, the African savanna elephants (Loxodonta africana) that populate the grasslands of Eastern and Southern Africa. Forest elephants are smaller with straighter tusks and live in the rainforests of Central and West Africa where they maintain tropical ecosystems through seed dispersal and germination, as well as nutrient recycling and herbivory.

Published in Ecology and Evolution, this recent study analyzed the nuclear DNA of 94 forest elephants from six locations. Forest elephant nuclear DNA is genetically diverse, yet this diversity is consistent across populations throughout Central Africa — any differences are too small to warrant treating them as distinct subspecies.

This nuclear DNA lacks the geographic patterns preserved in forest elephants’ mitochondrial DNA, the small proportion of the genome that is passed down only from mothers to their offspring. The mitochondrial DNA suggests that five genetically distinct populations existed in the past, most likely due to the Ice Age when their habitat was greatly restricted.

“Forest elephant’s seemingly discordant DNA can be easily explained by their behavior”, said lead author Yasuko Ishida, a research scientist in ACES. “Their mitochondrial DNA is a relic preserved by their matriarchal society.”

Females live together in matrilineal family groups, a herd is made up of related females who share the same mitochondrial DNA. Nuclear DNA diversity is controlled by the largest, mature males who travel long distances and promote gene flow by mating with distant females. Thus, females ensure mitochondrial DNA persists in local populations, while males ensure that the nuclear DNA is shared across populations.

“However, all of this precious DNA may soon be eradicated as forest elephants face extinction due to poaching and habitat loss”, Roca said. “Between 2002 and 2011, poachers wiped out more than half of their population. Fewer than 100,000 forest elephants are estimated to remain today — we must act swiftly to preserve them, and by extension, their habitats.”

African Triassic paleontology, new study


This 2016 video is called Monsters and Dinosaurs | Triassic | Age of Dinosaur | Documentary Film HD.

From the University of Washington in the USA:

Decade of fossil collecting gives new perspective on Triassic period, emergence of dinosaurs

March 28, 2018

Summary: A project spanning countries, years and institutions has attempted to reconstruct what the southern end of the world looked like during the Triassic period, 252 to 199 million years ago.

After a great mass extinction shook the world about 252 million years ago, animal life outside of the ocean began to take hold. The earliest mammals entered the scene, and reptiles — including early dinosaurs — lived on Pangea, the name given to the giant landmass in which all of the world’s continents were joined as one.

A project spanning countries, years and institutions has attempted to reconstruct what the southern end of this world looked like during this period, known as the Triassic (252 to 199 million years ago). Led by paleontologists and geologists at the University of Washington, the team has uncovered new fossils in Zambia and Tanzania, examined previously collected fossils and analyzed specimens in museums around the world in an attempt to understand life in the Triassic across different geographic areas.

Findings from the past decade of fieldwork and analysis are reported in a publication of the Society of Vertebrate Paleontology, appearing online March 28. In total, 13 research papers detailing new fossils, geologic discoveries and ecological findings in the Triassic make up the society’s 2018 special-edition volume, published once a year in a competitive submission process.

“Most of what we know about the major mass extinction is from the South African Karoo Basin. I was always interested in understanding, do we see the exact same pattern around the world, or do we not?” said co-editor Christian Sidor, a UW biology professor and curator of vertebrate paleontology at the Burke Museum of Natural History and Culture.

“The fossil record can be great to understand timing and sequence, but not always great at looking at things in a geographic context.”

Since 2007, Sidor and his team of students, postdoctoral researchers, paleontologists and geologists have visited the Ruhuhu Basin of Tanzania five times and the Luangwa and mid-Zambezi basins of Zambia four times. They lived there for about a month at a time, often hiking for miles to find fossil sites and camping in villages and national parks. Once, they were even awakened by the stomping and calls of elephants only feet from their camp.

Each site in Tanzania and Zambia contains its own collection of fossils from the Triassic and other periods, but the goal of this decade-long project was to look across locations hundreds and thousands of miles apart to find similarities in the fossil records. Two papers describe the regional patterns and similarities across much of what used to be Pangea.

“These papers highlight what a regional perspective we now have — we have the same fossils from Tanzania, Antarctica, Namibia and more”, Sidor said. “We’re getting a much better Southern Hemisphere perspective of what’s going on in the Triassic.”

Most of the papers in the special edition discuss new fossil findings from the paleontological digs. One explains the discovery of a new species of lizard-like reptile called a procolophonid. Another details Teleocrater, an early dinosaur relative that walked on four crocodile-like legs. This finding was reported in Nature last year, but the new paper describes the animal’s anatomy in fuller detail.

Most of the remaining papers describe other animals that were present in the Triassic besides the early dinosaurs.

“This was a time when dinosaurs were just stepping onto the stage, and they were not very big and not very remarkable animals then”, Sidor said. “These papers really round out what dinosaurs were competing with before they became the dominant reptiles on land.”

In addition to the 13 papers that make up the special edition, the team has published 24 peer-reviewed papers as part of this project in the past decade.

More than 2,200 fossils were collected across Tanzania and Zambia over the last decade of fieldwork. Of the special edition’s 27 authors, many participated in fieldwork with Sidor since 2007, including co-editor Sterling Nesbitt, a former postdoctoral researcher at the UW and now an assistant professor at Virginia Tech.

Fossil hunting is an experience every member of Sidor’s lab can have, from undergraduates through postdoctoral researchers. Sidor and a team are going again this August.

“This has been what my lab has done, and all of my students have been involved in some way,” he said. Four of Sidor’s students and two postdoctoral researchers are co-authors of papers in the new special edition.