What coelacanths tell about brain evolution

This 2 February 2018 video says about itself:

Diving With Coelacanths

This video is part of the banquet presentation given by Richard Pyle at the 2013 Marine Aquarium Conference of North America (MACNA) in Ft. Lauderdale, Florida. It represents a video overview of a series of dives conducted in 2011 off Sodwana Bay, South Africa, to find and film living Coelacanths.

The video also shows what the habitat looks like at depths of 100-120 meters (330-400 feet) off Sodwana Bay. The dives were led by Peter Timm, and filmed by Robert Whitton, Daniel Stevenson and Richard Pyle.

From the European Synchrotron Radiation Facility:

Coelacanth reveals new insights into skull evolution

April 17, 2019

An international team of researchers presents the first observations of the development of the skull and brain in the living coelacanth Latimeria chalumnae. Their study, published in Nature, provides new insights into the biology of this iconic animal and the evolution of the vertebrate skull.

The coelacanth Latimeria is a marine fish closely related to tetrapods, four-limbed vertebrates including amphibians, mammals and reptiles. Coelacanths were thought to have been extinct for 70 million years, until the accidental capture of a living specimen by a South African fisherman in 1938. Eighty years after its discovery, Latimeria remains of scientific interest for understanding the origin of tetrapods and the evolution of their closest fossil relatives — the lobe-finned fishes.

One of the most unusual features of Latimeria is its hinged braincase, which is otherwise only found in many fossil lobe-finned fishes from the Devonian period (410-360 million years ago). The braincase of Latimeria is completely split into an anterior and posterior portion by a joint called the “intracranial joint.” In addition, the brain lies far at the rear of the braincase and takes up only 1% of the cavity housing it. This mismatch between the brain and its cavity is totally unequalled among living vertebrates. How the coelacanth skull grows and why the brain remains so small has puzzled scientists for years. To answer these questions, researchers studied specimens at different stages of cranial development from several public natural history collections.

Although many specimens of adult coelacanths are available in natural history collections, earlier life stages such as fetuses are extremely rare. Scientists hence used state-of-the-art imaging techniques to visualize the internal anatomy of the specimens without damaging them. They notably digitalized a 5 cm-long fetus, the earliest developmental stage available for Latimeria, with synchrotron X-ray microtomography at the European Synchrotron (ESRF). Over the last two decades, the ESRF has developed unique expertise in designing non-invasive techniques widely used for evolutionary biology studies.

In addition, the researchers also imaged other stages with a powerful Magnetic Resonance Imaging (MRI) scanner at the Brain and Spine Institute (Paris, France), and a conventional X-ray micro-CTscan at the Muséum national d’Histoire naturelle (Paris, France). These data were used to generate detailed 3D models, which allowed scientists to describe how the form of the skull, the brain and the notochord (a tube extending below the brain and the spinal cord in the early stages of life) changes from a fetus to an adult.

They also observed how these structures are positioned relative to each other at each stage, and compared their observations with what is known about the formation of the skull in other vertebrates.

In contrast to most other vertebrates, where the notochord is replaced by the vertebral column early in embryonic development, the notochord expands considerably in Latimeria. The dramatic enlargement of the notochord likely influences the patterning of the braincase, and might underpin the formation of the intracranial joint. The brain might also be affected by the enlargement of the notochord, as relative size dramatically decreases during development.

These results illuminate for the first time the development of the living coelacanth skull and brain, and open up new avenues for research on the evolution of the vertebrate head.

Hugo Dutel, lead author and research associate in palaeobiology at the University of Bristol, UK, says, “These are very unique observations, but they represent only a tiny step forward compared to the amount we know on the development of other species. There are still more questions than answers! Latimeria still holds many clues for our understanding of vertebrate evolution, and it is important to protect this threatened species and its environment.”


Buffalo saved by colleagues from lions, crocodiles

This 9 April 2019 video from South Africa says about itself:

Herd Rescues Buffalo from Lions and Crocodiles

Over a decade ago, there was an epic battle between lions, buffaloes and a crocodile at a waterhole called Transport dam. That video was aptly named Battle at Kruger.

Well, 10 years later, the next generations of lions at Transport Dam recently faced their own failed hunt due to a huge herd of buffalo and crocodiles interfering!

Thuli Khumalo, head of Atamela Tours, captured this heart-pumping sighting while on a tour to the Kruger National Park. After lunch at Skukuza Rest Camp, Atamela’s game drive full of tourists arrived at the world-famous Transport Dam, in the hopes of seeing some action. Little did they know what they were actually in for.

They spotted a pride of lions lying in the shade, overlooking the water. If you spot lions hiding in the shade at a waterhole, it is often a good idea to stick around. Lions are opportunistic, so they will often try and hunt any animal that comes close enough.

Surely enough, a large herd of impala went down to the water and the lions gave chase! The impalas were too fast for the lions, but at the edge of the water, they spotted an old buffalo bull. The lions chased that buffalo and it ran into the water where out of nowhere, a crocodile starts taking a go at the already targeted buffalo. The buffalo decides that the water is probably more dangerous than on land, where it can potentially outrun the pride of lions that are now waiting for him to re-emerge from the water.

As soon as the buffalo hit the surface, he makes a run for it, with the lions following close on its tail. When buffaloes are under threat, they will call for help. Luckily, for this buffalo, his calls were answered! A massive herd of buffalo that was on its way to the dam saw the commotion and chased the lions away, saving the life of a fellow buffalo, unbeknown to us if it is from the same herd.

Elephant kills rhino poacher, lions eat him

This April 2017 video from the Kruger National Park in South Africa says about itself:

This might be the Cutest Elephant Attack ever! Baby Elephant joins Mom in Charge. Funny!

This Elephant Calf decided to join it’s Mom in a charge towards safari tourists. The little Elephant tries to keep up and eventually hit the front when it suddenly and (very proudly) gives a warning trumpet towards the tourists!

“It was a very memorable encounter. Our guide thought that there could be a problem as soon as we came upon the group and told us that we may have to reverse quickly to leave them alone. How right he was.”

However, not always elephant attacks in Kruger are so bloodless; and not always the targets are non-violent tourists.

Translated from Dutch NOS TV today:

Rhino poacher killed by elephant and eaten by lions

In South Africa, a suspected rhino poacher has cruelly encountered the dangers of nature. He was killed by an elephant and then eaten by lions. A group of five were poaching in the Kruger National Park. One of them was attacked by an elephant and died then.

The other four informed relatives of the victim, who in turn warned the authorities. Park rangers went to the scene of the incident, but because it was getting dark, they couldn’t find the victim. The next day they did find him, but then it turned out that lions had taken advantage of the corpse. The rangers only found the skull and pants of the man.

The national park has indicated in a statement that it is unwise to enter Kruger illegally on foot. “There are many dangers and this incident proves that.” The other four poachers have been arrested, they will be tried.

Big five

The Kruger National Park is located in the northeast of South Africa, along the border with Zimbabwe and Mozambique. With over 19,000 square kilometers, it is almost half the size of the Netherlands. All types of the big five are found in the park: lion, leopard, rhino, elephant and buffalo.

Poachers are a big problem just like in other game parks in Africa. They are often looking for the ivory of the tusks of elephants or the horn of rhinos.

African dung beetle rolls big ball

This 20 February 2019 video from South Africa says about itself:

Dung Beetle Rolls Enormous Dung Ball with Difficulty (4K)

The Addo flightless dung beetle isn’t one to give up – even when the ball of dung he’s pushing is easily 20 times his size. He’ll roll it all the way home for as long as it takes.

Honey badger saves baby from leopard

This 5 February 2019 video from South Africa says about itself:

Honey Badger Rescues Her Baby from Leopard

We all know that honey badgers think they are the boss of the bush… Well, this mother honey badger surely is! She had no second thoughts charging in on a hungry leopard to save her baby.

This incredible and unusual interaction was filmed by Sahara Wulfsohn, a 28-year-old guide at Kirkmans Kamp in the Sabi Sands Game Reserve in the Greater Kruger National Park.

Honey badgers survive lions

This 25 January 2019 video says about itself:

Lions intimidated by the fierce honey badgers

Honey badgers are known for their fearless nature and fierce attitude but even they are a bit cautious by their standards when facing a whole lion pride, nonetheless they left the scene unharmed simply due to their ferocious attitude.

Occurred on September, 2017 / Thornybush Nature Reserve, Rivonia, South Africa

Video filmer: “The video was taken on my morning game drive. We were tracking lions and found them but the lions got up and were moving. While they were moving, the lions and us in the game viewing vehicle stumbled upon the honey badgers. The badgers now had to move away from the vehicles and try and scare the lions away, which is not easy when you are drastically smaller than both. The badgers are extremely fierce animals and lions generally stay away from them. Some lions needed a new lesson on what they are cable of doing.”

Credit: Game Drive Channel via ViralHog