Mammal-like reptile’s brain, new research


Kawingasaurus fossilis at Museum of Paleontology, Tuebingen, Germany

From the Universität Duisburg-Essen in Germany:

A skull with history: A fossil sheds light on the origin of the neocortex

June 26, 2017

According to a recent study an early relative of mammals already possessed an extraordinarily expanded brain with a neocortex-like structure. This has been discovered by Michael Laaß from the Institute of General Zoology at the University of Duisburg-Essen (UDE).

Today, mammals possess large and efficient brains. But, what was the bauplan of the brain of their far relatives, the therapsids? When and why evolved the neocortex?

For his doctoral thesis the palaeontologist Michael Laaß invesitgated a ca. 255 million years old fossil skull of the therapsid Kawingasaurus fossilis in collaboration with Dr. Anders Kaestner from the Paul Scherrer Institute in Switzerland by means of neutron tomography and reconstructed the internal cranial anatomy in 3D.

The results were amazing: The relative brain volume of Kawingasaurus was about two or three-times larger than in other non-mammalian therapsids. Laaß: “Interestingly, Kawingasaurus already possessed a large forebrain with two distinct cerebral hemispheres.” Obviously, a neocortex-like structure at the forebrain similar to the mammalian neocortex was present in this animal.

Why is this brain structure evolved in Kawingasaurus? “Kawingasaurus was a burrower and special sensory adaptations were crucial for life under ground,” explained the UDE scientist. For example, this therapsid possessed frontally placed eyes, which were probably useful for binocular vision in dimlight environments as it is known from modern cats and owls. Furthermore, extremely ramified trigeminal nerve endings penetrated the snout, which might be an indication for a well developed sense of touch. The inner ear vestibules were also very large, which suggests that Kawingasaurus was well adapted to detect seismic vibrations from the ground.

Laaß: “These special sensory adaptaions also required a more efficient neural processing of the brain than in other therapsids.” It seems reasonable that these special adaptations of the sense organs and the brain to underground life triggered the expansion of the brain. Interestingly, a similar scenario for the origin of the neocortex has been also proposed for early mammals. Consequently, the recent study at the UDE supports this hypothesis.

Moreover, the new discovery also shows that a neocortex-like structure already developed in the therapsid Kawingasaurus about 25 million years earlier before the emergence of the first mammals. However, Kawingasaurus was not a direct ancestor of mammals. Consequently, neocortex-like structures evolved several times independently in pre-mammalian and mammalian evolution.

Dutch Aert Schouman’s eighteenth century bird, orangutan paintings


Sunbittern and secretary bird, 24 June 2017

As I wrote in another blog post, on 24 June 2017 we were at the exhibition in the Dordrechts Museum in Dordrecht, the Netherlands of art by Aert Schouman (1710-1792). Founded in 1842, with that exhibition the museum celebrates its 175 years of age. Much of the paintings depict birds; like this African secretary bird on the right, and American sunbittern on the left. I saw beautiful sunbitterns in Costa Rica.

The photos in this blog post are cellphone photos.

Barn swallow and strawberry plant by Schouman

This is another one of Schouman’s many bird pictures at the exhibition: a barn swallow at a strawberry plant.

Orangutan, 24 June 2017

Schouman did not only paint birds. He also depicted this orangutan; featuring a golden pheasant and antelopes.

That ape was the first orangutan who ever went from Borneo to Europe, in 1776. To Prince William V’s private zoo, at the Kleine Loo estate near Voorburg town. Prince William’s servants had no idea how to care for the young female ape. They tried to feed the vegetarian meat. However, as the painting shows, the orangutan preferred apples.

Orangutan detail, 24 June 2017

The fruit turned out to be not enough for the primate to survive a Dutch winter. She died in January 1777, a few months after her arrival.

Southern bald ibis, 24 June 2017

Another animal which Schouman depicted for Prince William V was the southern bald ibis from southern Africa. The photo shows this bird species, copied by Simon Fokke from a big Schouman painting.

With this copy, we have arrived at the subject of the last part of the Schouman exhibition: his influence on other Dutch artists, especially in depicting birds.

Eclectus parrot, 24 June 2017

For instance, this 1767 painting by Gerrit van den Heuvel of a female eclectus parrot shows Schouman’s influence.

Dog and mallard, 24 June 2017

So does this painting of a dog disturbing a flying mallard, a grey heron and mute swans.

Whydahs and parrot, 24 June 2017

And this one, of two African birds: pin-tailed whydah on the left and queen whydah on the right. And below them, a Philippine hanging parrot.

Duck and dog, 24 June 2017

There is much action in Schouman’s bird pictures. That is reflected in this painting by Wouter Uiterlinninge: a dog attacks a domestic duck. In panic while fleeing, the bird tramples her own eggs, damaging them.

Children's art, 24 June 2017

In the last hall of the Schouman exhibition, children can make their own art inspired by birds. In this photo, centre bottom, two flamingos: a pink one, presumably adult. And a white one, presumably young. A child has put a red heart on that bird. A house martin flies toward the flamingos.

African impala escapes from leopard


This video says about itself:

Impala Miraculously Escapes Jaws Of Leopard – The Hunt – BBC Earth

23 June 2017

With a burst of speed of 65 km an hour, the leopard without doubt is a formidable predator. In this tense and compelling encounter, we stalk quietly alongside a leopard as it sizes up an unsuspecting impala, from the cover of a gully.

Rare pond bats research


This 23 June 2017 Dutch video shows pond bats, rare in the Netherlands, being freed by biologist Anne-Jifke Haarsma after transmitters have been affixed to their backs for research.

New Zealand giant insect escapes from pigs


This video says about itself:

Tusked Weta Vs Foraging Pig – Wild New Zealand – BBC Earth

22 June 2017

The Tusked Weta is New Zealand’s equivalent of a mouse and a worthy snack for a foraging pig. This weta however is an escape artist and when necessary can take quite extreme action to evade capture.

American pine martens, new research


This 2015 video from the USA is called The Ever-Adorable Pine Marten.

From The University of Montana in the USA:

Previously unknown pine marten diversity discovered

June 22, 2017

The elusive American pine marten, a little-studied member of the weasel family, might be more diverse than originally thought, according to new research published by a University of Montana professor.

A study by Natalie Dawson, research professor in UM’s Department of Ecosystem and Conservation Sciences and director of UM’s Wilderness Institute, suggests that the forests of northwest North America may harbor not one, but two distinct species of the mammal. The research, published in a recent edition of the Journal of Mammology</em>, also points to the presence of hybrid marten populations in Montana’s Rocky Mountains, where the two species converge.

Dawson, whose work builds on previous research conducted in the 1950s by late UM Professor Philip Wright, examined hundreds of DNA samples to differentiate between the separate populations. She said her findings are exciting because hybridization in different species of mammals is still relatively new, especially in natural ecosystems.

“This is one of the few cases where there has been long-term hybridization between species that still maintain their distinctiveness in their respective localities,” she said. “This research also illustrates the importance of historical climate change as a driver for biological diversity in the mountains and landscapes of Montana, as well as throughout the rest of North America.”

Currently, Dawson is furthering her research by examining historical pine marten skulls housed in UM’s Philip L. Wright Zoological Museum in hopes of understanding the morphological, or physical, characteristic differences between the two species.

African leopards, new study


This 2015 documentary video is about leopards in Africa.

From the University of California – Santa Cruz in the USA:

African leopards revealed: Study documents minute-to-minute behavior of elusive cats

Results illuminate the energetic ‘cost’ of their drive to kill and pave the way for greater understanding of the ecosystem impacts of predation

June 21, 2017

The elusive behavior of the African leopard has been revealed in great detail for the first time as part of a sophisticated study that links the majestic cat’s caloric demands and its drive to kill.

A team led by Chris Wilmers, associate professor of environmental studies at the University of California, Santa Cruz, produced an unprecedented picture of this carnivore’s predatory and reproductive behaviour by outfitting the cats with high-tech wildlife tracking collars equipped with GPS technology and an accelerometer to measure energy output.

“This is the first time we’ve had really detailed energetic data from a wild terrestrial mammal over an extended period,” said Wilmers, lead author of a new paper, “Energetics-informed Behavioral States Reveal the Drive to Kill in African Leopards,” which appears today (June 21, 2017) in the online edition of the journal Ecosphere.

The team gathered data from five animals over two months: one adult male; one adult female with one cub; one adult female without cubs; one yearling male cub; and a young “dispersal-aged” male ready to establish his own territory. “The sample size is small, but we got lucky with the diversity of age and sex,” noted Wilmers.

Information gleaned from the collars allowed Wilmers’ team to match the leopards‘ behavior with time and place, enabling them to assess the energetic “costs” of reproductive behavior — dispersal and territorial patrol for males; parenting for females.

The study revealed that for male African leopards, territorial patrol activities account for 26 percent of their daily caloric intake; for females, parenting a one-year old offspring consumes 8 percent of their calories.

“Energetics is the ultimate currency for an animal’s survival,” said Wilmers. “To survive, an animal needs to balance the calories it’s expending with the calories it’s taking in. If it wants to reproduce, it has to run an energetic surplus.”

Wilmers, a wildlife ecologist who studies animal behavior and its cascading effects on ecosystems, continued: “Based on what the leopards are doing, they run up different energetic budgets, which in turn influence their drive to kill. They might kill more prey, bigger prey, or go after more desirable prey in more dangerous places — closer to humans, for example.”

One of the most striking behaviors described in the study was a kill by the adult male leopard. The data document him approaching a small village in a meandering fashion. He attacks and kills a goat inside a pen, then spends five minutes dragging the goat across the river to a spot where vegetation gives him the cover he needs to begin feeding.

“It gives us incredible insight into their behavior to see where they are moving and what they’re doing on such a fine time scale,” said Wilmers. “This allows us to see these cryptic animals moving through their environment.”

Another example details the behavior of the adult female with a yearling cub. She kills an aardwolf (a small insect-eating [hyena-like] mammal), feeds a bit, then meanders and rests for a few hours until she kills an impala (a medium-sized antelope that is common prey for African leopards). She feeds briefly, then walks directly back to her cub, guiding it first to the aardwolf and then the impala.

Additionally, Wilmers was able to calculate and then compare the energetics of the mother and her son as they traveled together, concluding that the cub expended 12 percent more energy to travel the same distance.

African leopards are among the most elusive mammals on the planet — more so than African lions or cheetahs. “Their whole strategy is to be elusive,” said Wilmers. “People get glimpses of them, but that’s all. Looking at this data is like going on a safari for the first time and seeing an animal you’ve only seen in captivity before.”

These fine-grained energetics data open the door to understanding the ecological consequences of the leopard’s predatory drive. Knowing the African leopard’s energetic needs allows researchers to evaluate where they hunt, what they hunt, and to estimate the level of risk they might be willing to take in pursuit of attractive prey. In combination, these factors have implications for humans and the livestock that often share habitat with African leopards.

The placement of a fence, for example, could have energetic “costs” for leopards if they have to travel farther — expending more energy — to patrol territory, hunt, and provide for their offspring. Those costs would increase their drive to kill. “They might take bigger risks, they might catch larger prey like impala, and that could effect the impala population and what they feed on,” said Wilmers, outlining the “cascade” of ecosystem effects that could follow human changes to the landscape.

“To be able to link behavior to energetics to ecological effects is an important conceptual advance,” said Wilmers. “Once you understand how that circle works, we can assess how our actions will impact the animals, and how those effects will play out on the ecosystem.”