Africa cradle of humankind, where in Africa?


This 15 November 2016 video says about itself:

Ain El Hanech (North Eastern Algeria)

The Algerian famous archeological site. Although there is uncertainty about some factors, Aïn el-Hanech (in Algeria) is the site of one of the earliest traces of hominid occupation.

From the Centro Nacional de Investigación sobre la Evolución Humana (CENIEH) in Spain:

The whole of Africa was the cradle of humankind

Oldest stone artifacts and cutmarked bones in North Africa contemporary with archaeological materials in East Africa

November 29, 2018

A team of scientists led by Mohamed Sahnouni, archaeologist at the Centro Nacional de Investigación sobre la Evolución Humana (CENIEH), has just published a paper in the journal Science which breaks with the paradigm that the cradle of humankind lies in East Africa, based on the archaeological remains found at sites in the region of Ain Hanech (Algeria), the oldest currently known in the north of Africa.

For a long time, East Africa has been considered the place of origin of the earliest hominins and lithic technology, because up to now, very little was known about the first hominin occupation and activities in the north of the continent. Two decades of field and laboratory research directed by Dr. Sahnouni have shown that ancestral hominins actually made stone tools in North Africa that are near contemporary with the earliest known stone tools in East Africa dated to 2.6 million years.

These are stone artifacts and animal bones bearing marks of cutting by stone tools, with an estimated chronology of 2.4 and 1.9 million years, respectively, found at two levels at the sites of Ain Boucherit (within the Ain Hanech study area), which were dated using Paleomagnetism, Electron Spin Resonance (ESR), and the Biochronology of large mammals excavated together with the archaeological materials.

Fossils of animals such as pigs, horses and elephants, from very ancient sites, have been used by the paleontologist Jan van der Made, of the Museo Nacional de Ciencias Naturales in Madrid, to corroborate the ages yielded by Paleomagnetism, obtained by the CENIEH geochronologist Josep Parés, and ESR, found by Mathieu Duval, of Griffith University.

Oldowan technology

The artifacts of Ain Boucherit were manufactured of locally available limestone and flint and include faces worked into choppers, polyhedra and subspheroids, as well as sharp-edged cutting tools used to process animal carcasses. These artifacts are typical of the Oldowan stone technology known from 2.6-1.9 million-year-old sites in East Africa, although those from Ain Boucherit show subtle variations.

“The lithic industry of Ain Boucherit, which is technologically similar to that of Gona and Olduvai, shows that our ancestors ventured into all corners of Africa, not just East Africa. The evidence from Algeria changes the earlier view that East Africa was the cradle of Humankind. Actually, the whole of Africa was the cradle of humankind,” states Sahnouni, leader of the Ain Hanech project.

Not mere scavengers

Ain Boucherit is one of the few archaeological sites in Africa which has provided evidence of bones with associated marks of cutting and percussion in situ with stone tools, which shows unmistakably that these ancestral hominins exploited meat and marrow from animals of all sizes and skeletal parts, which implied skinning, evisceration and defleshing of upper and intermediate extremities.

Isabel Cáceres, taphonomist at the IPHES, has commented that “the effective use of sharp-edged tools at Ain Boucherit suggests that our ancestors were not mere scavengers. It is not clear at this moment whether they hunted, but the evidence clearly shows that they were successfully competing with carnivores and enjoyed first access to animal carcasses.”

The tool-makers

At this moment, the most important question is who made the stone tools discovered in Algeria. Hominin remains have still not been found in North Africa which are contemporary with the earliest stone artifacts. As a matter of fact, nor have any hominins yet been documented in direct association with the first stone tools known from East Africa.

Nevertheless, a recent discovery in Ethiopia has shown the presence of early Homo dated to 2.8 million years, most likely the best candidate also for the materials from East and North Africa.

Scientists thought for a long time that the hominins and their material culture originated in the Great Rift Valley in East Africa. Surprisingly, the earliest known hominin, dated to 7.0 million years, and the 3.3 million years Australopithecus bahrelghazali, have been discovered in Chad, in the Sahara, 3000 km from the rift valleys in the east of Africa.

As Sileshi Semaw, scientist at the CENIEH and a co-author of this paper, explains that the hominins contemporary with Lucy (3.2 million years), were probably roamed over the Sahara, and their descendants might have been responsible for leaving these archaeological puzzles now discovered in Algeria, that are near contemporaries of those of East Africa.

“Future research will focus on searching for human fossils in the nearby Miocene and Plio-Pleistocene deposits, looking for the tool-makers and even older stone tools,” concludes Sahnouni.

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Songbirds singing and dancing, new study


This November 2015 video says about itself:

Hidden Bird “Tap-Dancing” Behavior Revealed in Slow-Motion​ Footage | National Geographic

High-speed footage reveals a unique courtship behavior of the blue-capped cordon bleu that has never been observed before in birds.

From Hokkaido University in Japan:

Couples showing off: Songbirds are more passionate in front of an audience

October 3, 2018

Both sexes of a songbird called the blue-capped cordon-bleu intensify courtship performances that involve singing and dancing in the presence of an audience, especially if it is a member of the opposite sex, an international team of researchers has discovered.

Mutual courtship displays have generally been understood as a form of private communication between a male and a female, and many researchers have focused on this aspect. The cordon-bleu is a socially monogamous songbird found in Africa. In its courtship display, both sexes sing and sometimes add a unique dance that resembles tap dancing.

Birds that live in flocks like cordon-bleus are thought to carry out courtship communications in the presence of other birds. However, very little research has been conducted on whether the individuals performing courtship displays are influenced by the presence of other birds. In the present study published in Science Advances, researchers from Hokkaido University in Japan and the Max Planck Institute for Ornithology in Seewiesen, Germany, focused on this so-called audience effect.

In the experiment, the researchers placed paired couples in situations with and without an audience and observed their behavior.

The researchers found that cordon-bleu couples tended to sing more courtship songs accompanied by dancing when an audience — especially if it is a member of the opposite sex — is present. In contrast, courtship displays without dancing were suppressed. As the birds were directing their courtship dancing toward their partners rather than the audience, Nao Ota of the research team concludes: “Performing a more elaborate courtship display toward a partner likely is meant to advertise the relationship to other individuals, which is a significant act among birds who live in flocks.” Researchers hypothesize that loyalty and bonding are necessary for cordon-bleu pairs to maintain long-term coupling relationships.

“This could provide insights into how complex communication signals have developed among animals, including human beings, that establish coupling relationships”, Nao Ota added.

Giraffe babies inherit spots from their mothers


This 2015 video from South Africa says about itself:

Incredible! Giraffe giving birth in the wild!

Captured by Capture the Wild in the Sabi Sands Reserve, Tydon’s Bush Camp.

From Penn State university in the USA:

Giraffe babies inherit spot patterns from their mothers

October 2, 2018

Some features of a giraffe‘s spot pattern are passed on from mother to baby, according to a new study led by researchers from Penn State. The study also reveals that survival of young giraffes is related to spot pattern, which may help provide camouflage from predators. The new study, published October 2 in the journal PeerJ, confirms a 49-year-old hypothesis about the inheritance of giraffe spots and highlights a new toolset that can be used to study the markings of wild animals.

“Giraffe spot patterns are complex and can be quite different among individuals, but we don’t really know their purpose in the wild”, said Derek E. Lee, associate research professor at Penn State and first author of the paper. “Complex markings can help animals evade predators, regulate their temperature, or recognize family or individuals, all of which can affect their ability to survive and reproduce. In this study, we analyzed survival records and photos of spots of Masai giraffes, and show that spot patterns do affect juvenile survival and are heritable — they are passed from mom to baby.”

Giraffe skin color is uniformly dark gray, but their spots are highly variable in color and shape, ranging from nearly round with very smooth edges to elliptical with jagged or lobed edges. Spot patterns do not change as an animal ages, which allows researchers to identify individuals based on their unique patterns.

This study revealed that newborn giraffes with larger spots and irregularly shaped spots also had increased survival during the first few months of life. This increased survival could reflect better camouflage of these young giraffes, but it also could be related to other survival-enhancing factors, such as temperature regulation or visual communication.

The study also found that two of eleven spot traits measured, circularity — how close the spot is to a perfect circle — and solidity — how smooth and complete the edges are — were significantly similar in mothers and calves. This suggests that these traits are inherited by the calf.

“Dr. Anne Innis Dagg, the first giraffe field researcher in Africa, presented evidence in 1968 that the shape, number, area, and color of spots in giraffe coat patterns may be heritable, but her analysis came from a small zoo population”, said Monica Bond, graduate student in evolutionary biology and environmental studies at the University of Zürich and an author of the paper. “We used wild giraffes and modern imaging and analysis techniques to confirm her conclusions.”

This study also highlights how modern image software and statistical methods can be used to reliably analyze complex coat patterns.

“My hope is that other scientists will use the same tools to measure mammal coat patterns to advance our understanding of what these patterns mean,” said Lee. “Quantifying heritability and fitness consequences of variation in coat patterns could help us understand how and why complex coat patterns evolve in wild animals.”

New bird species discovered in Africa


This 2016 video from Africa says about itself:

Watch this Olive Bushshrike calling and also making the ‘ting-ting-ting’ sound.

Olive bushshrikes are related to a newly discoverd African bird species.

From the American Ornithological Society Publications Office in the USA:

Newly identified African bird species already in trouble

September 19, 2018

Central Africa’s Albertine Rift region is a biodiversity hotspot consisting of a system of highlands that spans six countries. Recent studies have shown that the population of sooty bush-shrikes occupying the region’s mid-elevation forests is a distinct species, and new research from The Condor: Ornithological Applications reveals that this newly discovered species may already be endangered due to pressure from agricultural development.

The newly identified mid-elevation species has been dubbed Willard’s Sooty Boubou, as opposed to the previously recognized high-elevation species, the Mountain Sooty Boubou. The Field Museum’s Fabio Berzaghi (now with the CEA Laboratory for Sciences of Climate and Environment in France) and his colleagues used museum records and bird survey records to analyze the ecological niche occupied by each species, and their results confirm that there is very little overlap between the ranges of the two species — Willard’s Sooty Boubou is found at approximately 1200-1900 meters and the Mountain Sooty Boubou at 1800-3800 meters. In Burundi, Rwanda, and Uganda, 70% of the potential for Willard’s Sooty Boubou lies outside of protected areas and has been converted to agriculture, and the numbers for the Democratic Republic of Congo are only slightly better.

Willard’s Sooty Boubou joins several other imperiled bird species that depend on the region’s mid-elevation forests, which have been largely overlooked by conservation efforts. “The Albertine Rift is a crossroads of amazing biodiversity, dramatic and diverse landscapes, and heartbreaking social and political unrest. It goes from glaciers to volcanoes to plateaus to lakes, with a succession of vegetation types from high-elevation cloud forests to lowland tropical forests”, says Berzaghi. “It is home to gorillas and forest elephants as well as a high number of endemic animal and plant species. Unfortunately, much of the region has gone through never-ending conflicts, with very negative consequences for both humans and biodiversity, and conservation involving local populations is paramount.”

“This paper provides additional data in support of the recognition of Willard’s Sooty Boubou as a species distinct from Mountain Sooty Boubou. Clarification of the niche that Willard’s Sooty Boubou occupies, that of mid-elevation forests, distinct from the higher-elevation Mountain Sooty Bouboy, is important, because these habitats are among the most heavily impacted in Africa from agriculture”, according to UC Berkeley’s Rauri Bowie, an expert on African birds who was not involved in the study. “Conservation agencies have an opportunity to move beyond taxonomic debate and use the models derived from this species to improve conservation outcomes for not only this species, but also a broad set of mid-elevation Albertine Rift endemic vertebrates through protection of mid-elevation forests that have received relatively little protection in comparison to high-elevation montane habitats.”