The Sahara Desert has Grown 10% Since the 1920s

The Sahara Desert has expanded by about 10 percent since 1920, according to a new study by National Science Foundation (NSF)-funded scientists at the University of Maryland (UMD).

The research is the first to assess century-scale changes to the boundaries of the world's largest desert. It suggests that other deserts could be expanding as well. The study is published today in the Journal of Climate.

"The trends in Africa of hot summers getting hotter and rainy seasons drying out are linked with factors that include increasing greenhouse gases and aerosols in the atmosphere," says Ming Cai, a program director in NSF's Division of Atmospheric and Geospace Sciences, which funded the research. "These trends have a devastating effect on the lives of African people, who depend on agriculture-based economies."

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Studying the African Neolithic Transition Through Genetics

Scientists from the Institut Pasteur set out to understand how the demographic changes associated with the Neolithic transition also influenced the efficacy of natural selection. By comparing the genome diversity of more than 300 individuals from groups of forest hunter-gatherers (pygmies) and farmers (Bantu-speaking peoples), from western and eastern Central Africa, they discovered that the reason pygmies did not suffer from excessive deleterious mutations was because of their genetic diversity and their admixture with the Bantu peoples.

Research into the diversity of the human genome and any rare or frequent mutations is vital in identifying mutations that increase susceptibility to "complex" diseases, such as infectious or autoimmune disorders. "The elimination of these mutations that are harmful for human health is largely conditioned by the evolutionary history of populations, especially their demographic fluctuations," explains Lluis Quintana, Head of the Human Evolutionary Genetics Unit and author of the study. Throughout their history, human populations have undergone significant and extremely varied changes in terms of numbers of individuals, giving rise to differences in the number and severity of mutations carried by these populations. The accumulation of disease-causing genetic variants, known as the "burden of deleterious mutations", varies from one population to another depending on its past. "The aim of our project is to understand how demographic events such as the rise and fall in numbers of individuals, as well as genetic admixtures, have had an impact on the efficacy of some evolutionary mechanisms such as purifying selection."

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People Deforested the Central African Tropical Rain Forest 2,600 Years ago

The forested expanses of Central Africa host the second largest block of tropical rainforest on Earth (after Amazonia), stretching over around 2 × 106 km2. They are the great green heart of Africa, and changes in vegetation cover are likely to have important but poorly understood influences on the climate of much of the continent (1). A remarkable feature is that this blanket of forest appears quite tenuous—under the arid climates of the ice ages, the forest appears to have retreated into isolated pockets surrounded by savanna grasslands. Even in the climatically stable Holocene, there appears to have been periods of substantial forest retreat. In particular, there is evidence for a period of major forest loss between 3,000 and 2,000 y ago [termed the Late Holocene rainforest crisis (LHRC) (2)]. Attributing the cause of this decline is complicated by the fact that this period coincided with major expansion of Neolithic and early Iron Age farmers southward from the Nigeria/Cameroon border regions into western Central Africa. Did the farmers take advantage of a forest retreat driven by climate drying, or were they the primary cause of the forest loss? In recent years, there has been a vigorous debate on the cause of the LHRC. Now, Garcin et al. (3) provide new data and an unexpected new insight, presenting strong evidence that there was no strong drying event, and therefore suggesting that it was direct deforestation that caused this retreat of the Central African rainforests.

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Better start rethinking the anthropocene, folks.

Africa was Wetter During the Medieval Warm Period

Hydroclimate in Africa during the Medieval Climate Anomaly

Authors:

Lüning et al

Abstract:

The Medieval Climate Anomaly (MCA) is a recognized period of distinct pre-industrial climate change, with a core period of 1000–1200 CE. The field of palaeoclimatology has made major progress over the past 15 years during which a great number of high- and medium-resolution case studies were published, reconstructing climate change of the past millennia. In many parts of the world, regional data coverage has now reached a point which allows compiling palaeoclimate maps for well-defined time intervals. Here we present hydroclimatic trend maps for the MCA in Africa based on 99 published study locations. Key hydroclimatic proxy curves are visualized and compared in a series of 16 correlation panels. Proxy types are described and possible issues discussed. Based on the combined MCA dataset, temporal and spatial trends are interpreted and mapped out. Three areas have been identified in Africa in which rainfall seems to have increased during the MCA, namely Tunisia, western Sahel and the majority of southern Africa. At the same time, a reduction in precipitation occurred in the rest of Africa, comprising of NW and NE Africa, West Africa, Eastern Africa and the Winter Rainfall Zone of South Africa. MCA hydroclimate change in Africa appears to have been associated with characteristic phases of ocean cycles, as also supported by modern climate observations. Aridity in Morocco typically coincides with the positive phase of the North Atlantic Oscillation (NAO), whilst increased rainfall in the western Sahel is often coupled to the positive phase of the Atlantic Multidecadal Oscillation (AMO). Reduction in rainfall in the region Gulf of Aden/southern Red Sea to Eastern Africa could be linked to a negative Indian Ocean Dipole (IOD) or a derived long-term equivalent Indian Ocean cycle parameter. The Intertropical Convergence Zone (ITCZ) appears to have been shifted pole-wards during the MCA, for both the January and July positions. MCA hydroclimate mapping revealed major data gaps in the Sahara, South Sudan, Somalia, Central African Republic, Democratic Republic of Congo, Angola, northern Mozambique, Zambia and Zimbabwe. Special efforts are needed to fill these gaps, e.g. through a dedicated structured research program in which new multiproxy datasets are created, based on the learnings from previous African MCA studies.

China's Other Base in Africa

The construction of the campsite of China's first peacekeeping helicopter detachment to Sudan was completed in Al Fashir, Sudan on the morning of July 20, local time.

The project has passed the acceptance inspection by the engineering department of the African Union/UN Hybrid Operation in Darfur (UNAMID) and is now ready to accommodate the Chinese peacekeepers.

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Chinese Troops are now Based in Djibouti

China’s People’s Liberation Army Navy (PLAN) has despatched its first troop contingent to Djibouti ahead of the official establishment of the East Asian country’s first military support base in a foreign country.

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Mesolithic Humans Did NOT Cause Significant Environmental Changes?!

Environmental records obtained from archaeological sites suggest climate may not have been directly linked to cultural and technological innovations of Middle Stone Age humans in southern Africa, according to a study published July 6, 2016 in the open-access journal PLOS ONE by Patrick Roberts from the University of Oxford, UK, and colleagues.

The Middle Stone Age marked a period of dramatic change amongst early humans in southern Africa, and climate change has been postulated as a primary driver for the appearance of technological and cultural innovations such as bone tools, ochre production, and personal ornamentation. While some researchers suggest that climate instability may have directly inspired technological advances, others postulate that environmental stability may have provided a stable setting that allowed for experimentation. However, the disconnection of palaeoenvironmental records from archaeological sites makes it difficult to test these alternatives.

The authors of this study carried out analyses of animal remains, shellfish taxa and the stable carbon and oxygen isotope measurements in ostrich eggshell, from two archaeological sites, Blombos Cave and Klipdrift Shelter, spanning 98,000 to 73,000 years ago and 72,000 to 59,000 years ago, respectively, to acquire data regarding possible palaeoenvironmental conditions in southern Africa at the time. For instance, ostrich eggshell carbon and oxygen stable isotope levels may reflect vegetation and water consumption, which in turn vary with rainfall seasonality and amount in this region.

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Traces of Storms From the PaleoArchean Found

Sedimentology of the ∼3.3 Ga upper Mendon Formation, Barberton Greenstone Belt, South Africa

Authors:

Trower et al

Abstract:

The Mendon Formation is the uppermost unit of the 3.5–3.26 Ga Onverwacht Group in the Barberton Greenstone Belt, South Africa. It consists of a cyclic stack of komatiitic volcanic units separated by thin cherty sedimentary layers. In most areas, the uppermost Mendon Formation is a sedimentary interval characterized by black chert, banded black-and-white chert, and banded ferruginous chert, although the detailed patterns of lithofacies in different sections are more complex. Previously reported zircon U/Pb ages suggest that Mendon deposition could represent more than 70 Myr of time between ∼3334 Ma and ∼3260 Ma.

This study presents sedimentological and petrographic observations of the upper Mendon Formation from across the central part of the Barberton Greenstone Belt in order to investigate sediment sources, depositional processes, and environments of sedimentation. The dominant mode of sedimentation was quiet settling of carbonaceous grains and, in the deepest sections below storm wave base, fine ferruginous material, resulting in finely laminated black and grey chert. In situ carbonaceous laminations are rare, suggesting that benthic microbial mat growth had little direct influence on deposition. The hemipelagic background deposition was punctuated by occasional inputs of fine pyroclastic debris, formation and deposition of silica granules, and reworking by infrequent storm events. Storm deposits are represented by coarse-grained, poorly-sorted intraclast breccias, some of which include distinctive intraclasts sampling lithofacies that are not observed in situ. Despite considerable lateral variability, correlative temporal trends are resolvable in many Mendon sections: there is an upward-deepening of the overall depositional setting recorded in the oldest upper Mendon sections, consistent with the previous interpretation that Mendon time was characterized by rifting (Lowe, 1994a, 1999a). Younger Mendon cycles include thick, relatively ferruginous basal sections, interpreted to reflect the deepest water deposition. These sections are capped by black chert and silicified ashes with more evidence of disturbance and reworking by storms, reflecting gradual shoaling. This sedimentological analysis is broadly consistent with previous geochemical and tectonic analyses and provides a better picture of depositional patterns during uppermost Onverwacht time, before the distinct change in tectonic regime marked by impact spherule layer S2 and the onset of Fig Tree Group orogenesis and related siliciclastic deposition.

Tracking African Migrations of People Through the Last 4,000 Years Through Genetics

Researchers from the University of Oxford have revealed that the genetic ancestries of many of sub-Saharan Africa's populations are the result of historical DNA mixing events, known as admixture, within the last 4,000 years.

Their study, to be published in the journal eLife, uncovers signatures of these admixture events through a large analysis of DNA from populations across the continent. The discovery provides a foundation for the recent genetic history of the continent, which could aid future studies of non-communicable and infectious diseases, such as malaria.

While admixture has been demonstrated in other regions of the world, the new analysis has allowed the team to characterise sub-Saharan Africa's mixing events in an unprecedented level of detail.

"As Africa has few written records of its history, it is somewhat unknown what important movements of people generated the populations in the continent today," says lead author George Busby, Statistical Geneticist at the Wellcome Trust Centre for Human Genetics.

"Looking at and comparing the differences in the genomes of people alive today can help us better understand and reconstruct the historical interactions that brought their ancestors together."

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Nabotherium: a new Anthracothere From Oligocene Paleogene Egypt With Interesting Dental Adaptations

A new anthracothere (Artiodactyla) from the early Oligocene, Fayum, Egypt, and the mystery of African ‘Rhagatherium’ solved

Authors:

Sileem et al

Abstract:

Recent work on new anthracothere (Mammalia, Artiodactyla) specimens from the Jebel Qatrani Formation, early Oligocene, Fayum, Egypt, has revealed the presence of a new genus. Nabotherium new genus is described on the basis of a partial skull, several mandibular and maxillary specimens, and isolated teeth. The new genus exhibits a distinctive combination of features not seen in other Paleogene anthracotheres. The most noticeable characteristics of the new genus include the presence of large and well-developed upper and lower canines, caniniform third incisors, the presence of only a short diastema between the canine and first premolar, and broad, bunodont cheek teeth. This is in contrast to other contemporary anthracotheres, including other forms from the Fayum, which show a spatulate third incisor, a reduced canine, a much longer canine-premolar diastema, and more narrow, bunoselenodont cheek teeth. The presence of a relatively short rostrum with closely packed incisors, low-crowned and simple premolars, and low-crowned, bunodont molars indicates that members of the new genus would have been more efficient at crushing foods than slicing vegetation, and suggests a more varied herbivorous and frugivorous diet than was favored by other, more bunoselenodont Fayum anthracotheres.

Evidence of a Mesoproterozoic/Neoproterozoic Eukaryote Diversification in Africa

A diverse and exquisitely preserved organic-walled microfossil assemblage from the Meso–Neoproterozoic Mbuji-Mayi Supergroup (Democratic Republic of Congo) and implications for Proterozoic biostratigraphy

Authors:

Baludikay et al

Abstract:

A well preserved and diversified microfossil assemblage is reported from the Meso–Neoproterozoic Mbuji-Mayi Supergroup in the Kasai oriental Province, central part of Democratic Republic of Congo. A total of 49 taxa belonging to 27 genera were identified, including 11 species of unambiguous eukaryotes, 10 species of possible eukaryotes or prokaryotes and 28 species of probable bacteria. This assemblage is more diverse than previously reported but includes taxa reported in coeval worldwide assemblages. It is characterized by abundant sphaeromorphs, filamentous colonial aggregates and filamentous forms, as well as a relatively low diversity of acanthomorphs including the Late Mesoproterozoic and Early Neoproterozoic index fossil – Trachyhystrichosphaera aimika – reported for the first time in Central Africa. This species co-occurs with other taxa also reported for the first time in Africa: Trachyhystrichosphaera botula, Jacutianema solubila, cf. Tappania sp., Valeria elongata and numerous other taxa. Correlation with other geochronologically constrained successions that contain Trachyhystrichosphaera confirms T. aimika as promising index fossil to define the Late Mesoproterozoic–Early Neoproterozoic interval. The available biostratigraphic data enable to suggest a minimum Tonian age for the Mbuji-Mayi Supergroup. This age is consistent with the published and new geochronological data. Comparison with worldwide Proterozoic assemblages permits to define microfossil assemblages useful for biostratigraphy. This study significantly improves our understanding of the diversity of the Late Mesoproterozoic–Early Neoproterozoic biosphere, and in particular the diversification of early eukaryotes, preserved in the Democratic Republic of Congo rock record and more broadly in Africa where micropaleontological investigations are sparse.

The age of Madumabisa (Zambia) Fossil Vertebrates From Permian

Resolving the age of Madumabisa fossil vertebrates: Palynological evidence from the mid-Zambezi Basin of Zambia

Authors:

Barbolini et al

Abstract:

Age estimates for Permian rocks in the mid-Zambezi Basin of Zambia have thus far yielded ambiguous results. Previously studied palynoassemblages from the Madumabisa Formation resemble spore-pollen suites from both the Cistecephalus Zone of North Luangwa (Lopingian) and the palynological Assemblage Sub-Zone IV H of Zimbabwe, proposed as Guadalupian. In order to improve age estimates and refine the biostratigraphy of the Madumabisa Formation, this formation together with the underlying Gwembe Formation, were sampled for palynomorphs. Assemblages from the Gwembe Formation are dominated by trilete spores with less common striate and non-striate bisaccate pollen, whereas the overlying Madumabisa Formation palaeoflora is composed predominantly of striate bisaccates. Ferns, pteridosperms, lycopods, sphenophytes, glossopterids and conifers are represented in the palynofloras. The upper Gwembe Formation palynoassemblage can be correlated with the Didecitriletes ericianus Zone of Backhouse (1991), the Guttulapollenites hannonicus–Protohaploxypinus rugatus Zone (Zone VI) of Aitken (1998), Assemblage Zone III of the mid-Zambezi Basin, Zimbabwe and Biozone KK 3 in the Kalahari Karoo Basin, Botswana, suggesting a Guadalupian (Wordian–Capitanian) age. The upper Madumabisa Formation palynoassemblage can be placed in the upper Dulhuntyispora parvithola Zone of Backhouse (1991)/APP5 of Price (1997), dated as Wuchiapingian (Lopingian) and correlates with Assemblage 2 of the Moatize–Minjova Basin, Mozambique and the McKinnon Member palynofloras of East Antarctica. It also resembles Daptocephalus (formerly Dicynodon) Assemblage Zone palynofloras of the lower and middle Balfour Formation in the Karoo Basin, South Africa, and is suggested to be Lopingian (Wuchiapingian–Changhsingian) in age. Although these palynological assemblages place lower and upper age constraints on Madumabisa Formation vertebrate fossils, uncertainty remains as to the exact correlation between the Madumabisa vertebrate assemblages and the assemblage zones of the main Karoo Basin.

A new Synthesis of Archaean Crustal Evolution in West Africa

Archaean crustal evolution in West Africa: A new synthesis of the Archaean geology in Sierra Leone, Liberia, Guinea and Ivory Coast

Author:

Rollinson

Abstract:

A new synthesis of the geology and geochronology of the little-known Archaean rocks in Sierra Leone, Liberia, Guinea and Ivory Coast is presented in order to better understand the processes of Archaean crustal evolution in this region, and to attempt to interpret these data in the light of our current understanding of Archaean crustal evolution. In addition, this study seeks to identify those aspects of Archaean crustal evolution which are currently not known in this area and which need to become the subject of future studies, given the economic importance of this region in terms of the mineral deposits hosted in the Archaean rocks. These include greenstone-belt hosted iron ore, lode gold, chromite and columbite–tantalite and younger diamondiferous kimberlites intrusive into Archaean felsic gneisses.

The new results show that this cratonic nucleus comprises of four main geological units:

(1)  The oldest crust is made up of 3.5–3.6 Ga TTG (tonalite–trondhjemite–granodiorite) gneisses. These only outcrop in the east of the craton in Guinea but their presence is indicated elsewhere in the central part of the craton though xenocrystic zircon cores in younger rocks.

(2) The major rock type found throughout the craton is 3.26–2.85 Ga TTG gneiss. In detail these magmas are thought to have formed in two episodes one between 3.05–3.26 Ga and the other between 2.85–2.96 Ga. The presence of inherited zircons in the younger suite indicate that this event represents the partial reworking of the older gneisses. 3.4 Ga eclogite xenoliths in kimberlite derived from the sub-continental lithospheric mantle are thought to be the restite after the partial melting of a basaltic protolith in the production of the TTG magmas.

(3)  Supracrustal rocks form linear belts infolded into the TTG gneisses and metamorphosed to amphibolite and granulite grade. They are of different sizes, contain a variety of lithological sequences and may be of several different ages. The larger supracrustal belts in Sierra Leone contain a thick basalt-komatiite sequence derived by the partial melting of two different mantle sources, unconformably overlain by a sedimentary formation. They are seen as an important resource for gold, iron-ore, chromite and columbite–tantalite.

(4) A suite of late Archaean granitoids formed by the partial melting of the TTG gneisses in a craton wide deformation-metamorphic-partial melting event at 2800 ± 20 Ma. This thermal event is thought to be responsible for the stabilisation of the craton.

This new synthesis highlights major geological and geochronological similarities between the Archaean rocks of Sierra Leone, Liberia, Guinea and Ivory Coast and those in the Reguibat Shield in the northern part of the West African Craton suggesting that the two regions were once more closely related.

Evidence of a Continental Collision Between Laurentia & Rodinia From Stenian MesoProterozoic Africa?

U–Pb Zircon (SHRIMP) ages of granite sheets and timing of deformational events in the Natal Metamorphic Belt, southeastern Africa: Evidence for deformation partitioning and implications for Rodinia reconstructions

Authors:

Mendonidis et al

Abstract:

This study provides constraints on the ages of deformation events and fabric development in deformed rocks of the Margate Terrane of the Natal Metamorphic Province. The Margate Terrane forms the southernmost of three terranes considered to represent multiple arc accretion onto the southern margin of the Kalahari Craton, and geochronological data indicate that the Margate Terrane has a long history of sporadic magmatism from ∼1180 to ∼1025 Ma. Two granite sheets of differing structural age, as revealed by deformational fabric and cross-cutting relationships, were sampled for U–Pb (SHRIMP) dating from coastal outcrop at Southbroom (30°54′43.61″S, 30°20′1.61″E). The older sheet contains fabrics related to both D1 and D2 events, whereas the younger shows evidence for syn-D2 emplacement and contains an S2 fabric. For both intrusive sheets, zircon core domains showing magmatic zoning yielded ages that are statistically identical at 1075 ± 6 Ma. This is interpreted to represent the intrusion age of the older sheet, and to sampling of a xenocrystic population in the cross-cutting sheet due to assimilation. Zircons from both sheets show metamorphic rim zones with a mean age of 1042 ± 10 Ma, which is attributed to rim growth during development of the S2 foliation, close to the intrusion age of the younger sheet. The 1075 ± 6 Ma age is comparable to the ages of other granitic units in the Margate Terrane that intruded between ∼1091 and 1070 Ma and implies that all of these predated the D1 deformation, which is considered to record the accretion of the terrane onto the Kalahari Craton. The D2 event is characterized by northward-verging folds with a pervasive southward-dipping axial planar fabric S2, which largely overprinted the S1 fabric. Previously, the pure-shear D2 deformation was considered to be older than the narrow sinistral shear zones occurring within the Mzumbe and Margate Terranes. However, dating of the D2 event at 1042 ± 10 Ma indicates that these deformations are coeval, and represent deformation partitioning during a transpressional event at ∼1050–1025 Ma that may have been related to collision with Laurentia during the amalgamation of Rodinia.

The Great Wall of Kenya

Kenya has confirmed it will begin construction of a 700-kilometer-long security wall along the northeastern border with Somalia as part of a broader national security plan to curb cross-border terror attacks by Somali terrorist group al-Shabab.

Addressing the media in Nairobi over the weekend, Kenya's Interior Cabinet Secretary Joseph Nkaissery said that contrary to assertions by the Somali government and some influential clans and communities on either side of the border, the fence would not limit or deter the movement of people between the two countries.

Instead, he said the fence would limit cross-border terrorist movements and enable the country to prevent attacks which have killed more than 400 people in the country since 2012.

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Remains of Miocene Neogene Hominoid Nacholapithecus kerioi From Northern Kenya

Sacral vertebral remains of the Middle Miocene hominoid Nacholapithecus kerioi from northern Kenya

Authors:

Kakuchi et al

Abstract:

This study describes two new sacral specimens of Nacholapithecus kerioi, KNM-BG 42753I and KNM-BG 47687A, from the Aka Aiteputh Formation in Nachola, northern Kenya, excavated in 2002. They are of roughly equal size and are considered to belong to males. When scaled by body mass, the lumbosacral articular surface area of the better preserved specimen, KNM-BG 42753I, is smaller than that in Old World monkeys but similar to that in extant great apes and New World monkeys, as well as Proconsul nyanzae. The relatively narrow dimensions of the first sacral vertebral body in the transverse and sagittal planes are characteristics of N. kerioi and P. nyanzae and similar to those of extant great apes. In N. kerioi, lumbosacral surface area relative to body mass is small. This may simply be an extension of a trend from the previously reported small thoracolumbar vertebrae to the sacrum. ​The first sacral vertebrae of N. kerioi and Epipliopithecus vindobonensis have a higher craniocaudal vertebral body reduction (CVR; a higher CVR indicates a wider cranial width relative to a narrower caudal width), similar to that in Old World monkeys. Old World monkeys have a higher CVR, and usually have three sacral vertebrae, fewer than seen in extant great apes, which have a lower CVR and four to six (sometimes as many as eight) sacral vertebrae. New World monkeys have a lower CVR than Old World monkeys, but generally possess only three sacral vertebrae, and have a large caudal articular surface, which may be related, at least in the Atelidae, to the grasping ability of their tails. The possibility that N. kerioi had only three sacral vertebrae cannot be ruled out, because E. vindobonensis and Old World monkeys, with higher CVRs, have sacra consisting of three sacral vertebrae.

Desert Mammals Disappeared at the Dawn of the Holocene Quaternary From Ethiopia

Paleoenvironmental and biogeographic implications of terminal Pleistocene large mammals from the Ziway–Shala Basin, Main Ethiopian Rift, Ethiopia

Authors:

Lesur et al

Abstract:

The terminal Pleistocene is a period of profound climatic and environmental change in Africa, with paleoenvironmental records documenting tremendous regional variation. Environmental records needed to understand these dynamics are currently lacking from the Horn of Africa. Here we provide a new paleoenvironmental record based of new faunal data from archeological sites along the Bulbula River (Ziway–Shala Basin, Main Ethiopian Rift) in Ethiopia. Research conducted in this area has uncovered archeological assemblages that document various phases of the Late Pleistocene and Early Holocene. Two sites dated to the terminal Pleistocene are considered here, B1s1 and B1s4. The former includes a very large assemblage of more than 20,000 skeletal remains. Both faunal assemblages are dominated by bovids of the tribes Alcelaphini and Antilopini and include Damaliscus hypsodon, a small extinct alcelaphine. The faunal remains from these sites, like those from the contemporary site of Lukenya Hill in south-central Kenya, are indicative of widespread arid grasslands. Several ungulates are found outside of their historic ranges, including Grant's gazelle (Nanger granti) and Dorcas gazelle (Gazella dorcas). Their absence from the region today likely reflects a combination of paleoenvironmental change since the end of the Pleistocene coupled with more recent human impacts. The combination of archeological and faunal data suggests that B1s1 could have been a residential site with seasonal occupation to acquire raw material from local obsidian sources and to hunt bovids in the arid plain, including species that ultimately disappear or shift their range at the onset of the Holocene with the return of warmer and moister conditions.

Homo habilis & Paranthropus boisei Pleistocene Quaternary Habitat was NOT the Garden of Eden

Scientists have pieced together an early human habitat for the first time, and life was no picnic 1.8 million years ago.

Our human ancestors, who looked like a cross between apes and modern humans, had access to food, water and shady shelter at a site in Olduvai Gorge, Tanzania. They even had lots of stone tools with sharp edges, said Gail M. Ashley, a professor in the Rutgers Department of Earth and Planetary Sciences in the School of Arts and Sciences.

But "it was tough living," she said. "It was a very stressful life because they were in continual competition with carnivores for their food."

During years of work, Ashley and other researchers carefully reconstructed an early human landscape on a fine scale, using plant and other evidence collected at the sprawling site. Their pioneering work was published recently in the Proceedings of the National Academy of Sciences.

The landscape reconstruction will help paleoanthropologists develop ideas and models on what early humans were like, how they lived, how they got their food (especially protein), what they ate and drank and their behavior, Ashley said.

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Mupashi migrator: a new Karenitid Therocephalian From Upper Permian Zambia

The first karenitid (Therapsida, Therocephalia) from the upper Permian of Gondwana and the biogeography of Permo-Triassic therocephalians

Authors:

Huttenlocker et al

Abstract:

Therocephalians were an ecologically diverse group of therapsids whose long stratigraphic record and widespread distribution during Permian and Triassic times make them important for understanding biogeographic patterns during a major faunal transition. Here, we describe a new therocephalian, Mupashi migrator gen. et sp. nov., from the upper Madumabisa Mudstone Formation (upper Permian) of Zambia's Luangwa Basin. The specimen has a long snout with a maxilla–vomerine contact on the hard palate, a high antecanine tooth count and numerous postcanines, and a conspicuous boss on the dentary angle whose structure is identical to that of the Russian baurioid Karenites. Additional endocranial anatomy, including palatal and braincase features, are revealed by high-resolution X-ray computed tomography and described in detail in light of the growing availability of tomographic data for therapsids. A phylogenetic analysis of 56 therapsid taxa and 136 cranial and postcranial characters recovers Mupashi as the sister taxon to Karenites, placing the pair between basal ictidosuchid-grade baurioids and the later Triassic bauriamorphs. Parsimony optimizations of geographic occurrences are ambiguous regarding the origination centers of therocephalian subclades. However, the patterns are suggestive of either (1) rapid, early dispersal events of Eutherocephalia and its major subgroups from a Laurasian center during the early–late Permian or, more likely, (2) within-province diversifications with occasional dispersal events occurring between provinces. Regardless, these associations strengthen the hypothesis that unknown but effective dispersal routes to high latitudes were available to therapsids and other tetrapods at least until early–late Permian times.

Ethiopia's Paleoclimate Became Humid, Wetter and Possibly Monsoonal During the Carnian/Norian Triassic

Paleoclimatic records of Late Triassic paleosols from Central Ethiopia

Author:

Dawit

Abstract:

The present study documents the major paleosols types within the Lower Adigrat Sandstone in the Blue Nile Basin of central Ethiopia, with the aim of unraveling the paleoclimatic signatures embedded in them. The paleosols developed within an 80-m-thick siliciclastic succession deposited in a mixed tide- and wave-dominated incised valley estuary during the Late Triassic.

Based on down-profile variations in pedogenic features, three major paleosol types (i.e., types I, II and III) were identified. Type I paleosols dominate the lower part of the section and are interpreted as moderately well-drained argillic Vertisols. The dominant pedogenic process was shrinking and swelling of expandable clays (i.e., smectite) through repeated wetting and drying cycles. The morphologies and the mineralogy of the paleosols provide persuasive evidence for pedogenesis under semi-arid subtropical climatic conditions with pronounced wet-dry seasonality, highly fluctuating soil moisture regime, and deep groundwater table. The presence of a calcic Bk horizon deep in the profiles is consistent with elevated soil moisture deficits and low to moderate mean annual precipitation (MAP). Type II paleosols, interpreted to represent vertic Gleysols, are more common in the middle part of the section. The pervasive gleying reflects poor soil drainage and a shallow groundwater table where the soil is waterlogged most of the year. These paleosols suggest a humid tropical climate characterized by alternating wet-dry seasonality but with more wet months per year. The top of the unit is dominated by type III paleosols that represent gleyed Oxisols, reflecting a more humid equatorial climate marked by wet seasons, elevated annual soil moisture content, and a high water table. The presence of plinthite/laterite is in agreement with a wet equatorial climate characterized by extensive chemical weathering and long periods of landscape stability.

The observed vertical progression in the major paleosol types from Vertsols to Gleysols and Oxisols implies a systematic change in the number of wet months, most probably in response to regional tectonics and long-term climate change. Because the number of wet months is, in part, related to latitude and monsoonal climates, the upward stratigraphic trend in paleosol orders is interpreted to signal the northward or equatorward migration of the Blue Nile Basin and central Ethiopia within Pangea from dry subtropical low-latitudes in the early Late Triassic (Carnian‐Norian) toward the humid, wet equatorial, possibly monsoonal, paleoclimatic zone in the Late Triassic (Norian‐Rhaetian).