Was There a Significant Human Influence on the Flora of North Africa During the Pleistocene & Holocene?

Pleistocene and Holocene herbivore diets and palaeoenvironments in the Gebel Akhdar (Libya): Implications for past human populations

Authors:

Reade et al

Abstract:

The Gebel Akhdar massif in Cyrenaica, northeast Libya, has yielded a long record of human occupation going back at least 100,000 years. To date, there is only a limited understanding of how the landscape of the region varied in response to the climatic fluctuations of the last glacial–interglacial cycle, and the implications of these changes for local human populations remain largely unexplored. This study provides an isotope-based interpretation of past environments directly linked to the archaeological record. Tooth enamel stable carbon isotope ratios (δ13C) from herbivore species hunted by past human populations are used to infer the isotopic characteristics of past diet and vegetation, and in turn the likely environmental conditions that prevailed during periods when humans were active within the landscape. To provide a baseline from which to interpret the archaeological δ13C data, modern samples are considered in relation to their diet and environmental origin. Archaeological samples come from 2 cave sites, Haua Fteah and Hagfet ed Dabba, and span a period from oxygen isotope stage 4 to the mid-Holocene. Whilst results indicate a more arid environment in the Pleistocene and an increase in humidity at the onset of the Holocene, the overall picture is one of relative environmental stability. The biggest landscape change observed in the data occurs during the mid-Holocene Neolithic, when C4 plant species become evident in the herbivore diet for the first time. There is little evidence to suggest that this occurred at a time of any large-scale climate variation, and thus the contribution of anthropogenic influences to vegetation change is considered likely.

Should Europe Cover the Sahara With Solar Panels for Power?

Could one solution to climate change be to harvest the power of sunlight where it shines brightest on the planet? Should we solar panel the Sahara desert?

Four experts discuss the radical proposal with the BBC World Service Inquiry programme.

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Apidium zuetina: a new Anthropoid Primate From Oligocene Paleogene Libya

During upheaval in Libya in 2013, a window of opportunity opened for scientists from the University of Kansas to perform research at the Zallah Oasis, a promising site for unearthing fossils from the Oligocene period, roughly 30 million years ago.

From that work, the KU-led team last week published a description of a previously unknown anthropoid primate -- a forerunner of today's monkeys, apes and humans -- in the Journal of Human Evolution. They've dubbed their new find Apidium zuetina.

Significantly, it's the first example of Apidium to be found outside of Egypt.

"Apidium is interesting because it was the first early anthropoid primate ever to be found and described, in 1908," said K. Christopher Beard, Distinguished Foundation Professor of Ecology and Evolutionary Biology and senior curator with KU's Biodiversity Institute, who headed the research. "The oldest known Apidium fossils are about 31 million years old, while the youngest are 29 million. Before our discovery in Libya, only three species of Apidium were ever recovered in Egypt. People had come up with the idea that these primates had evolved locally in Egypt."

Beard said evidence that Apidium had dispersed across North Africa was the key facet of the find. He believes shifting climatic and environmental conditions shaped the distribution of species of Apidium, which affected their evolution.

"We've found evidence that climate change -- not warming, but cooling and drying -- across the Eocene-Oligocene boundary probably is the root cause in kicking anthropoid evolution into overdrive," he said. "All of these anthropoids, which were our distant relatives, were living up in the trees -- none of them were coming down. When the world became cooler and dryer in this period, what was previously a continuous belt of forest became more fragmented. This created barriers to gene flow and movement of animals from one part of forest to what used to be adjacent forest."

With a forest broken up, there was an inhibition of gene flow that through time resulted in speciation, or the creation of new species, according to the KU researcher.

"Animals that are sequestered become different species over millions of years," Beard said. "As the climate oscillates again, you've got different species of Apidium. As forests expand and contract, now you've got competition between species of Apidium that have never seen each other before. One species outcompetes the other, the other goes extinct, and we think that's what we're picking up with this Libyan Apidium, which is related to the youngest and largest species of Apidium known from Egypt."

Beard said that Apidium zuetina would have been physically similar to modern-day squirrel monkeys from South America, but with smaller brains, and would have dined on fruits, nuts and seeds.

"We know that Apidium was a very active arboreal monkey, a really good leaper," he said. "We know they actually had fused lower-leg bones just above the ankle joint. That's really unusual for anthropoid primates, and the only reason for it to happen is because you like to jump a lot, as it stabilized the join between those bones and the ankle."

The team identified Apidium zuetina through detailed analysis of its teeth.

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First Evidence of a Wild Fire From Campanian Cretaceous North Africa

The first evidence of paleo-wildfire from the Campanian (Late Cretaceous) of North Africa

Authors:

El Atfy et al

Abstract:

Although the fossil record of plant macro- and mesofossils, including fossil charcoal, is patchy geographically and temporally, such remains play an important role for the interpretation of paleoenvironmental and paleoclimatic developments in the continental realm. In Egypt, previous palynological studies on the Upper Cretaceous (Campanian) deposits suggested presence of lush subtropical forests, dominated by angiosperms and pteridophytes, which developed under warm and wet climatic conditions. In the present study, the occurrence of paleo-wildfires during the Late Cretaceous (Campanian) is presented for the first time, based on samples from a surface exposure in the vicinity of the Baris Oasis, south Western Desert, Egypt. Macroscopic charcoal was collected and subsequently analyzed under a stereomicroscope and scanning electron microscope (SEM). The charred wood remains were identified as belonging to gymnosperms, which were important components of the North African paleoflora during the Cretaceous. These charcoal remains represent the first verified occurrence of paleo-wildfires in Africa during the Campanian.

French Architecture Firm Rediscovers Arcologies in Quest for 'Sustainable' Cities in the Sahara

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Middle Cretaceous Dinosaur Assemblages From northern Brazil and Africa

Middle Cretaceous dinosaur assemblages from northern Brazil and northern Africa and their implications for northern Gondwanan composition

Author:

Candeiro

Abstract:

Dinosaurs are one of the most dominant groups in Cretaceous reptilian faunas. A summary of their record in northern Brazil and northern Africa during the middle of the Cretaceous Period (Aptian-Cenomanian) is presented here. Dinosaurs are represented by 32 species (three ornithischians, six sauropods and 23 theropods) from Brazil, Egypt, Lybia, Morocco, Niger, Sudan and Tunisia. These dinosaur assemblages provide fundamental data about distribution and composition of sauropods and theropods in northern Gondwana during the middle of the Cretaceous Period and confirm these assemblages to be among the most important dinosaur faunas in the north Gondwana areas.

How the Environment Influenced Theropod Diversity in Aptian/Albian Cretaceous Tunisia

Integrating palaeoecology and morphology in theropod diversity estimation: a case from the Aptian-Albian of Tunisia

Authors:

Fanti et al

Abstract:

Current knowledge of theropod dinosaurs of northern Africa and their diversity during the Early Cretaceous is deceptively fragmentary and commonly associated with inadequate stratigraphic and palaeoecological data. Thereby, confused taxonomic affinities of theropod remains, represented primarily by isolated teeth and fragmentary skeletal remains, resulted in speculations on the number of genera and their stratigraphic, geographic and ecological distribution. In this study, we introduce a discussion on the theropod diversity in the Aptian–Albian of southern Tunisia based on a multidisciplinary approach that combines detailed sedimentological analyses with canonical morphological and phylogenetic analyses. This study indicates the presence of three theropod clades, Spinosauridae, Abelisauroidea, and Carcharodontosauridae. Relevant for the identification of isolated specimens from the Saharan regions, carcharodontosaurids are not represented in the Aptian-Albian teeth record and thus relatively less abundant than spinosaurids and abelisauroids. Five ziphodont tooth morphotypes are referred to ontogenetic and/or positional differences among a single abelisauroid taxon. The other three teeth morphotypes most likely represent two distinct spinosaurid taxa. Finally, the calibrated stratigraphic distribution of discussed elements indicates a clear ecological partition between theropod taxa. In particular, abelisauroids and carcharodontosaurids are commonly found in inland, fluvial deposits together with titanosauriform and rebbachisaurid sauropods, and rare crocodilians. Conversely, spinosaurids are limited to estuarine to coastal deposits dominated by a rich and diverse crocodilian fauna along with actinopterygians and sarcopterygians, including large-sized coelacanthiforms.

Dmitry Gorenburg @ Moscow Conference on International Security 2014: Russians on MENA

In addition to the plenary panel, the MCIS conference included two panel discussions, one on the Middle East and North Africa and the second on Afghanistan.

The panel entitled “Finding Ways of Stabilization in the Middle East and North Africa” was moderated by Vitaly Naumkin of the Institute of Oriental Studies. Participants included Deputy Russian Foreign Minister Mikhail Bogdanov, General Vladimir Zarudnitsky — the head of the Main Operational Directorate of the Russian Armed Forces General Staff, Deputy Syrian General Staff Chief Mahmoud Abdul Wahab Shawa. Deputy Director of the Israeli Institute for National Security Udi Dekel, Director of the Iranian Institute for Middle East Strategic Studies Kayhan Barzegar, Chief of Military Intelligence and Counterintelligence of the Lebanese Army Fadel Edmond, and CIS Executive Secretary Sergey Burutin.

Since I am not a MENA specialist, I was primarily interested in how the region influenced Russian foreign policy.

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Evidence Suggests Some Pre-NeoProterozoic Contribution to Southern Egyptian Crust

U-Pb zircon geochronology and Hf-Nd isotopic systematics of Wadi Beitan granitoid gneisses, South Eastern Desert, Egypt

Authors:

Ali et al

Abstract:

Migmatitic granitoid gneisses are widespread in the southern Eastern Desert of Egypt, but their formation ages are poorly understood. They consist of granitoid gneiss ranging in composition from tonalite to granodiorite, with a distinct calc-alkaline chemical character. Zircons from three migmatitic gneiss samples from Wadi Beitan were dated on SHRIMP II and yielded magmatic emplacement ages of 719 ± 10, 725 ± 9 and 744 ± 10 Ma, respectively, indicating that the gneiss protoliths are Neoproterozoic. The zircons yielded εHf(t) values of -4.8 to + 12.5 and corresponding Hf crustal model ages ranging from 824 to 1753 Ma. These data indicate the involvement of both juvenile and older continental crust in protolith formation. Positive whole-rock εNd(t) values (+ 5.1 to + 6.6) and corresponding Nd model ages of 690 to 830 Ma suggest a relatively young, juvenile Neoproterozoic crustal source for the Wadi Beitan granitic gneisses. However, a εNd(t) value of + 5.1 (sample WB-23) is less than predicted for a depleted mantle source at ~ 700 Ma (εNd of about + 6.5), perhaps indicating that there was minor contribution from old (pre-Neoproterozoic) crust. The chemical data and significant variations in both isotopic systems argue for source heterogeneity and may suggest that the Wadi Beitan granitoids formed along an active continental margin.

Were There Three Major Rivers in the Sahara During the Last Interglacial?

Three ancient river systems, now buried, may have created viable routes for human migration across the Sahara to the Mediterranean region about 100,000 years ago, according to research published September 11 in the open access journal PLOS ONE by Tom Coulthard from the University of Hull, UK, and colleagues from other institutions.

Simulating paleoclimates in the region, the researchers found quantitative evidence of three major river systems that likely existed in North Africa 130,000-100,000 years ago, but are now largely buried by dune systems in the desert. When flowing, these rivers likely provided fertile habitats for animals and vegetation, creating 'green corridors' across the region. At least one river system is estimated to have been 100 km wide and largely perennial. The Irharhar river, westernmost of the three identified, may represent a likely route of human migration across the region. In addition to rivers, the researchers' simulations predict massive lagoons and wetlands in northeast Libya, some of which span over 70,000-square kilometers. "It's exciting to think that 100 000 years ago there were three huge rivers forcing their way across a 1000km of the Sahara desert to the Mediterranean -- and that our ancestors could have walked alongside them" said Coulthard.

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