Million-and-a-half-year-old bone tools from Olduvai Gorge, Tanzania.

Hominins have been using stone tools to access meat from Animal carcases for at least 2.6 million years, and this use of stone tools is also presumed to have helped them switch to a significantly more carnivorous diet. Logically, a Hominin which can use stone tools to hunt large Animals should also be able to make tools from the bones of those Animals, but bone tools have a much more limited record than their stone counterparts.

A number of bone-objects from archaeological sites in Africa dated to between 2.5 and 0.8 million years ago have been interpreted as having been modified by use as tools, for such purposes as digging or Termite fishing, but do not appear to have been deliberately shaped prior to use. A few purpose modified tools have been repoted from Olduvai Gorge in Tanzania, but these were surface finds, lacking the context from which they could be dated. Bone tools are also known from the Konso site in Ethiopia, including a bone handaxe which has been dated to 1.4 million years ago. Bone tools start to appear across Eurasia around 500 000 years ago, and highly shaped bone tools, such as spear and arrow points, barbed points, awls and needles, appear in Africa about 90 000 years ago, spreading to Eurasia around 45 000 years ago.

In a paper published in the journal Nature on 5 March 2025, Ignacio de la Torre of the Instituto de Historia of the CSIC-Spanish National Research Council, Luc Doyon of the Université de Bordeaux, Alfonso Benito-Calvo of the Centro Nacional de Investigación sobre la Evolución Humana, Rafael Mora of the Facultat de Lletres at the Universitat Autonoma de Barcelona, Ipyana Mwakyoma, also of the Instituto de Historia of the CSIC-Spanish National Research Council, Jackson Njau of the Department of Earth and Atmospheric Sciences at Indiana University, and the Stone Age Institute, Renata Peters of the Institute of Archaeology at University College London, Angeliki Theodoropoulou, again of the Instituto de Historia of the CSIC-Spanish National Research Council, and Francesco d’Errico, also of the Université de Bordeaux, and of the SFF Center for Early Sapiens Behaviour at the University of Bergen, describe an assemblage of bone tools from a horizon at Olduvai Gorge Bed II, which has been dated to 1.5 million years ago.

The tools form part of an assemblage identified as the T69 complex, were derived from a layer between Middle and Upper Bed II, in the Frida Leakey Korongo West Gully at Olduvai Gorge, which has been  radiometrically dated to 1.5 million years ago. T69 complex materials have been derived from six tranches, the bulk of the material comprising early Acheulean stone tools. A total of 10 900 stone tools larger than 2 cm, and over 41 000 smaller artefacts have been recovered, mostly made from a local quartzite.

Geographic and stratigraphic context of the FLK T69 Complex site. (a) Location of Olduvai Gorge in Tanzania. (b) Main geographical features of the Olduvai Basin. The geographical image was adapted from the NASA /USGS ASTER Global Digital Elevation Model. (c) Position of the T69 Complex in the Main Gorge at Olduvai. (d) Stratigraphic position of the bone tool level shown on a composite section of the deepest part of trench T69 and the central area of the T69-T79 west section. (e) Position of the T69 Complex within the general chrono-stratigraphic sequence of Bed II in the Frida Leakey Korongo West Gully area. (f) Normal (left) and polarized (right) thin section photographs of the sandstone containing the bone tool horizon. De la Torre et al. (2025).

In addition to the tools, the assemblage contains abundant Vertebrate fossils, including 9419 identified bone fragments and 13 413 unidentified fragments. Many of the identifiable remains can be attributed to Fish, Crocodiles, and Hippopotamuses, suggesting that 1.5 million years ago, the site was close to water. The majority of the large Animals are Bovids and Hippopotamuses, with some relatively intact Hippopotamus carcasses present. Other large Animals present include Equids, Suids (Pigs), Rhinoceros, and Elephants. Hippopotamus bones are the most abundant, and many of these show signs of deliberate modification.

The faunal elements of the T69 assemblage, including bone tools, are excellently preserved, something not common at Middle Pleistocene sites, allowing for careful documentation and analysis of the material present. De la Torre et al. identify 27 artefacts as unequivocal stone tools, ruling out other forms of damage such as Carnivores gnawing, Crocodiles biting, trampling and fracturing to access marrow; in fact, Carnivore bones are very rare in the T69 assemblage, and the only signs of bone-modification by Carnivores are two possible tooth marks.

Tools are identified as bones with multiple fragments removed, which lack the striations associated with trampling. Experimental breaking of large Mammal bones to recover marrow failed to produce similar flaking. Patterns of breakage consistent with marrow-extraction are present on many bones present in the faunal assemblage, suggesting that this was something done by the Hominins here. This seldom results in more than two or three flakes being removed, whereas the 'tools' have an average of 12.9 flaking scars, typically arranged contiguously and preferentially on their lateral edges.

Twenty seven bone tools were recovered during excavations at Frida Leakey Korongo West Gully, eighteen of which are attributed to Mammals weighing more than two tonnes. Sixteen of these are identifiable, including eight tools made from Elephant bones, six tools are made from the bones of Hippopotamus, and two from the bones of large Bovids. Thus, in an assemblage dominated by Bovid bones, where 169 taxa are recorded and Elephant remains make up about 1.1% ot the total, more than half the tools are made from Elephant bones. One of the tools is made from the proximal portion of the radius of a large Bovid, all the others from long portion of limb bones, predominantly the femora, tibiae and humeri.

Tools made on long bone diaphysis of very large Mammals. (a) Indeterminable taxon larger than two tonnes (accession number T69L20-3009). (b) Elephant (accession number T79L10-2511). Scale bars are 5 cm. De la Torre et al.  (2025).

The Frida Leakey Korongo West Gully tools represent a set of technological and behavioural innovations previously unrecorded in Hominins of this antiquity. The tools are relatively 'fresh', which is to say they were apparently buried quite soon after being made, and do not show signs of having sat on the surface and subject to weathering. The Hippopotumus bone tools all appear to have been made from fresh bone (i.e. from Animals which had died shortly before the tools were made), but some of the Elephant bone tools appear to have been made from bones partially weathered before flaking occurred, suggesting that old Elephant bones were recognised as a valuable resource and collected separatley from scavenging carcases for food. Elephant bone tools range from 22 to 38 cm in length and from 8 to 15 cm in width, making them the largest in the assemblage. Hippopotamus bone tools are slightly smaller, 18 to 30 cm in length and 6 to 8 cm in width.

Elephant bone tools also show more working, showing on average 17.3 flake removal scars, compared to an average of 13.3 scars on Hippopotamus bone tools. Among the fifteen tools made from unidentified Animals, seven are comparable to Elephant or Hippopotamus bone tools in size, with similar numbers of scars, while eight are smaller, with an average of six flaking scars. The preferred method of tool making appears to have been to first remove large flakes to give the tools its shape, then remove smaller flakes to regularize the edge surfaces. Experimentally braking bones for marrow-extraction produced scars significantly shorter than the initial flaking used in tool production at Frida Leakey Korongo West Gully, indicating deliberate intent from the outset. The shape of the scars is compatible with the use of hand-held hammerstones, although these would have needed to be large and heavy.

Six of the large-Mammal bone tools show a recurrent shape, with one crescent-shaped end and one pointed end, combined with a large notch on the middle part of the tool. This was achieved using an average of 16.8 flake removals, the majority of which are associated with the creation of the notch. The pointed end of the tool corresponds to the robust part of the diaphysis (middle section) of the bone, which the rounded end appears to be derived from the metaphysis (wider, end-part) of the bone. 

Large bone tools made on diaphysis fragments. (a) Elephant humerus (accession number T79L10-9047). (b) Hippopotamus femur (accession number T79L10-18461). Scale bars are 5 cm. De la Torre et al. (2025).

The bone tools at Frida Leakey Korongo West Gully are larger, heavier, more elongated, and more worked than stone tools from the same site, suggesting that bone was deliberately chosen as the material of choice for such tools. The tool makers appear to have a good understanding of the properties bone as a material, and the anatomy of the Animals from which it was derived, preferentially choosing Elephant bone even when this was not fresh, and consistently making tools to the same plan, following a standard flaking pattern.

Recurrent distal fracture patterns on additional bone tools. (1) Tibia diaphysis of cf. Hippopotamus (accession number T69L20-1872; dimensions 222 × 80 × 54 mm). (2) Accession number T69L20-3633. (3) Accession number T77L64-823. (4) Elephant long bone diaphysis (accession number T78L84-75; dimensions 353 × 103 × 53 mm). Each scale bar segment is 1 cm. De la Torre et al. (2025).

The T69 technology from Frida Leakey Korongo West Gully represents evidence for bone tool production by Hominins 1.5 million years ago. Previously, our knowledge of bone tool use in the Early Stone Age consisted of bone fragments which had apparently been used as tools without modification, and isolated tools with possible evidence of working and/or dubious stratigraphy (dating), with the regular appearance of deliberately made bifacial bone tools not occurring till after 500 000 years ago. 

The Frida Leakey Korongo West Gully discovery shows that Hominins had a complex tool industry which included the production of large knapped bones a million years before bifaced bone tools become common. These tools date to a key period in technological innovation, during which the early Acheulean technology was replacing the late Oldowan technology, a change which probably reflects a general increase in behavioural complexity. This increased behavioural complexity appears to have included a greater ability to select materials, a better ability to imagine the shape of a finished tool and work towards it, and morse sophisticated knapping techniques to reach that end. At this point bifacial tools were starting to appear, forming a minor part of tool assemblages and not reaching the large sizes seen in later Acheulean assemblages. 

Hominins at this stage are known to have been scavenging the carcasses of large Mammals and actively developing butchery techniques, which would have made bone a readily available material. It is possible the large bone tools from the Frida Leakey Korongo West Gully fulfilled the same role as the large bifacial tools of later Acheulean assemblages, and that the development of these more advanced stone tools led to the abandonment of large bone tools. In this scenario, the bifacial bone tools of the Middle Pleistocene might represent a reversion to bone use among populations lacking access to good lithic material.

An alternative hypothesis is that bone technologies appeared and disappeared several times over the course of the Pleistocene, all being being slightly more common in the Early Stone Age than previously realised. Either way, Early Pleistocene use of bone tools is clearly an under-reported phenomenon, possibly due to collection bias (archaeologists finding stone tools, because that is what they are looking for). Further research may reveal earlier use of bone tools, as well as a more widespread use of bone as a tool making material in the Early and Middle Pleistocene.

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New material from the Middle Stone Age Dorothy Garrod archaeological site, in the Olduvai Gorge, Tanzania.

The Olduvai Gorge in Tanzania is famous for its archaeological sites, notably those associated with early Hominins and the appearance of the genus Homo. However, the area also produces later material, and in particular is home to a number of important Middle Stone Age sites, providing incite into a key stage in the development of Modern Humans. The Middle Stone Age material of the Olduvai Gorge is found within the Ndutu Beds, a succession of tuffacious (volcanic ash), aeolian (wind-blown) and fluvial (river deposited) sediments. These beds can be divided into Upper and Lower units, and are overlain by the Naisiusiu Beds, which produce Later Stone Age material.

Various attempts have been made at dating the Ndutu Beds, none of which is considered definitive. In the 1970s, Richard Hay used amino-acid dating to estimate that the Lower Unit of the Ndutu Beds was laid down between 400 000 and 60 000 years ago, while the Upper Unit is between 60 000 and 32 000 years old. In 1993 Paul Manega used  single‑crystal laser fusion to estimate that the Lower Unit is between 450 000 and 210 000 years old, and that the bottom of the Naisiusiu Beds dates from 42 000 years ago, while a decade later a team led by Anne Skinner dated the start of the Naisiusiu Beds to 62 000 years ago using electron spin resonance.

Two sets of fragmentary Human remains have been recovered from the Ndutu Beds, a palate and maxillary arch considered robust by modern standards, and which was consequently assigned to Homo sp., was described by Mary Leaky in 1971, and  partial calvaria (top part of the skull) assigned to Homo sapiens was described by a team led by Whitney Rainer in 2017. Both of these specimens are derived from the Upper Member of the Ndutu Beds, but neither has been directly dated.

The palate and maxillary arch were found at a location called Dorothy Garrod, which is on the northern side of the Main Olduvai Gorge, 200 m to the west of the KK Fault and opposite the junction with the Side Gorge. Mary Leaky believed the material here was related to the Middle Stone Age material from the Ngaloba Beds at Laetoli, but was not able to date it more precisely. In 1990 Audax Mabulla revisited the area, but again was unable to date the location. In the 2010s a team led by Metin Eren gathered a series of Middle Stone Age stone tools from Dorothy Garrod, but were not able to produce a date for the site.

In a paper published in the journal Archaeological and Anthropological Sciences on 18 August 2022, a team led by José Manuel Maíllo‑Fernández of the Department of  Prehistory and Archaeology at the Universidad Nacional de Educación a Distancia, and the Institute of Evolution in Africa at Alcalá University, presents the results of excavations at Dorothy Garrod, carried out in February and July 2018 and February 2019.

The same team previously carried out excavations at  the Victoria Cabrera Site, 400 m to the southwest of Dorothy Garrod, revealing several layers containing Middle Stone Age tools and faunal remains, which they were able to date to between 86 000 and 75 000 years before the present. 

(A)–(C) Location of Dorothy Garrod Site (DGS) and Victoria Cabrera Site (VCS) in the Olduvai Gorge; (D) view of the Dorothy Garrod Site excavation. Maíllo‑Fernández et al. (2022).

All of the exposed sediments at Dorothy Garrod are attributed to the Upper Unit of the Ndutu Formation, and are assumed to be slightly older than the sediments at Victoria Caberera, based upon their stratigraphic context, but has not been dated more accurately than this.

Excavations were carried out to a depth of 3.5 m, exposing a series of layers identified as Levels 1-4. Level 4, at the base of the sequence, is a perfectly sorted and cemented sand layer interpreted as aeolian in origin. Level 3 is a well sorted but poorly cemented tuffaceous silt, also interpreted as aeolian in origin, which yielded a variety of Middle Stone Age material. Level 2 is a well sorted and cemented tuffaceous silt, again interpreted as aeolian in origin, which produced no archaeological material. Level 1 is a well sorted and cemented very fine sand, which again produced no archaeological material.

Stratigraphic section of the Dorothy Garrod Site. Maíllo‑Fernández et al. (2022).

The faunal remains recovered from Dorothy Garrod comprise 247 fragments of bone, 27 teeth and fragments of teeth, two Ostrich shell fragments, and four terrestrial Mollusc shell fragments. Two of the teeth could be identified as those of Equids (Horses, Asses, Zebras etc.), a mandible could be assigned to the Hippotragini (Grazing Antelopes), and four teeth to the Alcelaphini (Wildebeest, Hartebeest, Bonteboks etc.). None of the other tooth or bone fragments could be identified. The bones were generally poorly preserved, at least in part due to the presence of sediment concretions which had affected the surface of many bones. Fifty eight of the bones show evidence of burning, while two (both interpreted as the long bones of Ungulates) have notches cut into them; only one has a carnivore tooth mark.

Faunal remains from the Dorothy Garrod Site. (1) Femur of Ungulate of size 1b with fresh bone breakage; (2) fragment of a femur of an Ungulate of size 2 with generalised sediment concretions; (3) fragment of a vertebra with burning; (4) fragment of a long bone of size 2 with burning damage; (5) fragment of a vertebra of ungulate of size 3 with generalised sediment concretions. Maíllo‑Fernández et al. (2022).

A total of 1179 lithic items were recovered from Level 3 at Dorothy Garrod, 40 of which showed signs of reatouching. Of these tools 113 were excluded from the study due to subsequent alteration, the majority of these being made from phonolite. 

Only six pieces showed signs of rounding (i.e. shaping by being rolled in an aquatic environment), and in only one case was this severe, so hydraulic damage (which can sometimes break rocks in a way that can resemble early stone tools) can be ruled out as a cause of the lithic assemblage. 

The assemblage included 615 blanks (pieces of rock of suitable size and shape to make stone tools from) with pseudo‑retouching (damage which at first site resembled the actions of a toolmaker). The majority of these are likely to have been caused by trampling, but a few may have been caused by a knapping process, in which they were removed from a rock source.

The majority (79.9%) of the tools at Dorothy Garrod are made from Naibor quartzite, a metamophicly recrystalized sandstone which outcrops at Naibor Soit Hill, 2 km to the north of the Olduvai Gorge. Another 8.2% are made from phonolite, derived from the Engelosen Volcano, 7 km to the north, and 3.6% are made of a basalt derived from the Lemagrut Volcano, 10-12 km to the south. The remainder of the material appears to be locally sourced, including sandstone (6.1%), hyaline quartz (1.4%), chert (0.3%), quartzite (0.1%), and gneiss (0.1%).

Only 7% of the blanks were completely covered by a cortex (the natural surface of a rock caused by chemical weathering, which is removed during toolmaking), while 18% had a partial cortex surface; over 75% had no cortex at all on at least one side.

Of the 757 worked blanks found, 458 could not be associated with any toolmaking scheme, while the remainder were either single platform blanks, or prepared core blanks, either discoid or Levallois. There were no bipolar cores.

Discoidal knapping (removing chips to be used as tools from the surface of a rock by working around it in a circular pattern) was the most common toolmaking method, with 26 discoid cores found, and 222 blanks with chips removed in a discoid pattern. Chips had been removed both unifacially (all from one side) and bifacially (from both sides). The most commonly used rock for this was Naibor quartzite, but some basalt and local quartzite were also used. The knapping had been used to produce chordal flakes, pseudo Levallois points, square f lakes, and flakes wider than they are long.

Lithics from Dorothy Garrod. (1) Discoid core; (2)–(4) discoid flakes. All on Naibor quartzite. Maíllo‑Fernández et al. (2022).

Only 24 blanks and 1 core had been exploited using the Levallois technique; forming a striking platform at one end of a stone tool, then trimming the core's edges by flaking off pieces around the outline of the intended lithic flake, prior to separating the tool with a final blow, which creates a tool with a distinctive plano-convex profile, and leaves a core with a rounded 'tortoiseshell' pattern. The core and the majority of the blanks were made using the centripetal Levallois technique, which can be difficult to tell from the discoidal method, and possibly evolved from it, with the remainder using the preferential, unidirectional, and bidirectional variants of the technique. No Levallois points were found.

Single platform knapping had been used to make 38 flakes and a single core. These were again predominantly made of Naibor quartzite, with phonolite, basalt, and hyaline quartzite also used.

Other cores at the site appeared to have been worked using the polyhedric and/or oportunistic methods (which can be hard to tell apart. A single Kombewa flake (large flake made by striking a core from two different sites) was discovered.

The majority of the retouched items were denticulate tools, followed by retouched flakes, notches, and sidescrapers. Two large retouched items were found, a bifacial and a transversal sidescraper. Again, the majority of these were made from Naidor quartzite. 

Lithics from Dorothy Garrod. (1) Unipolar Levallois flake; (2) pseudo Levallois flake; (3) preferential Levallois flake; (4) discoid flake; (5) denticulate on ordinary flake; (6) sidescraper on ordinary flake; (7) Centripetal Levallois core; (8) Centripetal Levallois flake; (9) unifacial discoid core. Raw materials: (1), (2), and (8): basalt; (2)–(7) and (9): Naibor quartzite. Maíllo‑Fernández et al. (2022).

The combination of a plentiful lithic assemblage and faunal remains showing signs of Human modification make the Dorothy Garrod Site a regionally important Middle Stone Age locality. The precise age of this deposit is still unknown, but only an area of 28 m² has been excavated, so it is quite possible that datable material will be uncovered in the future. The material does not appear to be preferentially orientated or abraded, suggesting that it has not been moved significantly by post-depositional processes. 

None of the Mammal remains are well preserved, but the vast majority appear to represent Ungulates, and many show signs of modification, either by burning or breaking. Although burning of bones is common, no charcoal usable for dating was recovered. Evidence of modification of the bones by non-Human predators was almost absent.

The majority of the tools found were made for which a manufacturing technique could be identified were made using the discoidal or Levallois methods, with single platform and opportunistic knapping being much less common, and only a single bifacial tool was found, and Levallois points were completely absent. A small number of tools showed signs of retouching. The majority of the tools were made from Naibor quartzite, sourced from a hill 2 km to the north.

The absence of datable material makes it hard to assess the age of the Dorothy Garrod Site, but it may be contemporary with the Kisele industry, found at Mumba Cave near Lake Eyasi and the Nasera Rockshelter in the Ngorongoro Conservation Area, and the Loiyangalanian industry from Loiyangalani in the Serengeti National Park. However, such comparisons are difficult to make; discoidal manufacture is common at almost all Middle Stone Age sites in East Africa, as is the use of materials obtained fairly locally, and while the tool-making appears closest to the Kisele and Loiyangalanian industries, both unifacial and bifacial points are common components of the Kisele industry, but absent at Dorothy Garrod, and bipolar knapping also absent at Dorothy Garrod, is a common feature at Loiyangalani. The low level of retouching at Dorothy Garrod may reflect the material being used; quartzite lends itself to this far less well than chert (rare at Dorothy Garrod) or obsidian (absent altogether).

Although Maíllo‑Fernández et al. have expanded on previous work at Dorothy Garrod, they consider the site still has much more to reveal. The site records a Middle Stone Age technology along with faunal remains almost certainly left by the tool-makers. The site has not been dated, but based upon comparison to tools from other sites it is probably dates from Marine Isotope Stage 5-Marine Isotope Stage 4 (i.e. is between 130 000 and 71 000 years old).

Further excavations at Dorothy Garrod have the potential to resolve the dating of the site, as well as shedding light upon Middle Stone Age patterns of settlement, and how these people interacted with their environment.

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Fossil Bats from the Early Pleistocene of Olduvai Gorge, Tanzania.

Bats are one of the most successful Mammal groups, with roughly 25% of all known living Mammal species being Bats (or about 50% of all living non-Rodent Mammal species). They have a fossil record dating back to the Paleocene, but their fossil record is not well studied as, like Birds, Bats have extremely light and fragile skeletons, with the effect that most fossil Bats are known from extremely limited and fragmentary material.

In a paper published in the American Museum Novitates on 16 December 2015, Gregg Gunnell of the Division of Fossil Primates at the Duke Lemur Center and the Department of Mammalogy at the American Museum of Natural History, the late Percy Buttler, formerly of the Royal Holloway University of London, the late Marjorie Greenwood, formerly of the Natural History Museum and Nancy Simmons, also of the Department of Mammalogy at the American Museum of Natural History describe a series of fossil Bats from the Early Pleistocene of Olduvai Gorge of Arusha Province in Tanzania. The bones were collected in the late 1950s and early 1960s from sediment sieved during the excavations that produced the first specimens of Zinjanthropus boisei. These deposits are thought to be between 1.80 and 1.85 million years old. Four new fossil Bat species are described from the remains.

The first new species described is placed in the genus Myzopoda and given the specific name africana, meaning 'from Africa'; there are two living species of Myzopoda today, both of which are found in Madagascar only. Older members of the family Myzopodidae (of which Myzopoda is the only living species) have previously been described from Africa, but this is the first species of Myzopoda. The species is described froma single whole left humerus, longer and more robust than those of either living species at 26.5 mm, plus two partial humeri. 

(A, C) Left humerus of Myzopoda africana, compared with (B, D) the living Madagascan species Myzopoda schliemanni, in anterior (A–B) and posterior (C–D) views. Gunnell et al (2015).

The second species described is placed in the genus Cardioderma and given the specific name leakeyi in honour of palaentologist Louis Leaky, for his work in East Africa. The genus Cardioderma contains a single living species, Cardioderma cor, the African Heart-nosed Bat, which is found across East Africa including Tanzania today. The species is described from a left maxilla and right dentary, both with teeth in place. The teeth of Cardioderma leakeyi are larger and more robust than those of Cardioderma cor. Fossils referred to the genus Cardioderma have previously been recorded from the Pliocene of Ethiopoa, though this material has never been formally described.

Upper dentition of Cardioderma cor (A) compared with Cardioderma leakeyi (B–D). (A) palate (photograph). Left maxilla with P4–M3 in (B, C) lateral (drawing and photograph of cast, respectively) and (D) occlusal (drawing) views. Gunnell et al (2015).

The third species described is placed in the genus Scotoecus (Lesser House Bats) and given the specific name olduvensis, meaning 'from Olduvai'. Five species of Scotoecus are alive today, four of them widespread in Africa, the other from South Asia. Scotoecus olduvensis is described from a left dentary with intact teeth and two fragments of humerus. This species also appears to have been larger and more robust than living species in the same genus. It is the first fossil species of Scotoecus described.

Left lower dentitions of Scotoecus in occlusal view. (A) Scotoecus albofuscus; (B) Scotoecus olduvensis; (C) Scotoecus hindei. Gunnell et al (2015).

The fourth specimen is a partial right humerus tentatively referred to the living species Eptesicus isabellinus, which is found today in North Africa and the Canary Islands and possibly Iberia, but which is considered by some to be a subspecies of Eptesicus bottae, a species found from North Africa across the Middle East and into Central Asia. Modern members of the genus are found across Africa, Europe, Asia, North, Central and South America and the Caribbean, with fossil specimens previously recorded from the Pliocene of Southern Africa and the Plio-Pliocen of the Northern Hemisphere.

Right distal humerus of cf. Eptesicus isabellinus in (A) anterior, (B) posterior, (C) medial, and (D) lateral views. Gunnell et al (2015).

The next specimen described is a fragment of left humerus assigned to the genus Myotis (Mouse-eared Bats). Modern members of this genus are found across Africa, Eurasia and the Americas, and is common in the fossil record of much of this area from the Pliocene onwards, though African fossil specimens have previously only been recorded in Southern Africa and Morocco.

Two more partial humeri are referred to the genus Pipistrellus, being similar to the modern species Pipistrellus nanulus and Pipistrellus rueppelli, both of which are found in Africa. Pipistrelle Bats are found across much of the globe today, and fossil specimens are known from a number of areas; they have previously been described from Olduvai, but not yet in the fossil record anywhere else in Africa.

The forth species described is placed in the genus Nycticeinops, and given the specific name serengetiensis, meaning 'from the Serengeti'. This species is described from a right and left dentary with some teeth and a second left dentary without teeth plus eleven partial humeri. The genus Nycticeinops contains only a single living species, Nycticeinops schlieffeni (Schlieffen's Twilight Bat) a widespread African species. Nycticeinops serengetiensis appears to have been slightly larger than Nycticeinops schlieffeni, though the modern species is particularly small (at about 3-4 cm), and Nycticeinops serengetiensis is still a small Bat. This is the first fossil species of Nycticeinops described.

 

 

Mandible of Nycticeinops schlieffeni, photographs in (A, lateral and (B) occlusal views compared with Nycticeinops serengetiensis, drawings. (C–E)  Nycticeinops serengetiensis, left dentary with m1–2 and all anterior alveoli in (C) occlusal, (D) lateral and (E) medial views. (F–H) Nycticeinops serengetiensis, right dentary with p4–m1 with all other alveoli in (F) occlusal, (G) lateral, and (H) medial views. Gunnell et al (2015).

 

The next specimen is a partial humerus tentatively referred to the living Mops condylurus, the Angolan Free-tailed Bat, a species widespread in Sub-Saharan Africa today.

 

 Right distal humerus of Mops cf. Mops condylurus in (A) anterior, (B) posterior, (C) medial, and (D) lateral views. Gunnell et al (2015).

 

The next specimens described are a complete left humerus plus a partial left and two partial right humeri referred to the living species Mops thersites, the Railer Bat, a widespread African species. The genus Mops is a member of the family Molossidae (Free-tailed Bats), previously only represented in Africa by an Early Miocene specimen of Tadarida from Kenya.

Left complete humerus of Mops cf. Mops thersites. (A) Photograph and drawing in posteromedial view; (B) drawing in medial view; (C) drawing in lateral view; (D) photograph and drawing in anterior view. Gunnell et al (2015).

The final group of specimens comprises a right dentary which had two teeth when first discovered but has subsequently lost one, plus eight partial humeri referred to the living Miniopterus schreibersi, or Common Bent-winged Bat, a species found today across much of Africa, Europe and Asia.

Comparison of extant Miniopterus schreibersi (A, C, E) photographs and fossiil Miniopterus cf. Miniopterus schreibersi (B, D, F) drawings in (A–B) occlusal, (C–D) lateral, and (E–F) medial views. Gunnell et al (2015).

The majority of the Bat species a either members of species or closely related to species found in dry-to-moist savannah or open woodland close to water today. This fits well with the interpreted environment of Olduvai in the Early Pleistocene, thought to have been open woodland with freshwater springs feeding into a nearby lake. However some of the Bats present, Pipistrellus, Eptesicus, and Scotoecus, are more typically found in drier or even semi-arid open woodland, which may suggest such habitats were present nearby.

See also...

 

Lonchophylla inexpectata: A new species of Nectar-feeding Bat from the Caatinga of Brazil.                                                                             Nectar-feeding Bats of the genus Lonchophylla are found tropical South and Central America, where they are important pollinators of...

The source of the December 2013 Guinean Ebola outbreak.                                                          In December 2013 cases of the haemorrhagic...

Nycteribiid Bat Flies from the southwest Indian Ocean.                                                           Nycteribiid Bat Flies are True Flies, Diptera, that have lost their wings and adopted a lifestyle as ectoparasites of Bats. They have an unusual lifestyle, with the larva maturing within the female Fly (which only produces one larva at a time), then being ‘laid’ during the pupa stage. The female Fly leaves her host Bat to lay this pupa, which hatches 3-4 weeks later, producing a new...

 

 

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Using morphometric analysis to understand the nature of Canid remains from Plio-Pleistocene Hominid sites from East Africa.

Morphometric analysis is a method used by palaeontologists to sort bones and shells into taxonomic and ecological groups. It relies on comparing the ratios of different measurements to one-another rather than simply assigning the samples to groups based upon their obvious shape. Such analyses have proved to be powerful tools for understanding certain groups, particularly Molluscs, which tend to have highly pre-determined growth patterns allowing the confident assignment of shells to taxa, and Mammals, which are often able to modify their bones within their lifetimes in response to environmental factors.

In a forthcoming paper in the journal Acta Palaeontologica Polonica available online from 23 September 2014, Carlo Meloro of the Research Centre inEvolutionary Anthropology and Palaeoecology at Liverpool John Moores University and Julien Louys of the Department of Archaeology and Natural History at the Australian National University attempt to apply morphometric analysis to a series of Canid (Dog) radii from palaeontological sites in East Africa from which Hominid remains have been recovered and extensively studied.

The remains used in the study were a complete left radius from Koobi Fora dated to between 2.6 and 2.0 million years old, a proximal fragment of a left radius from Olduvai dated to between 1.75 and 1.749 million years old, and a distal fragment of a right radius from Olduvai, dated to between 1.7 and 1.2 million years old. Whilst some of these specimens were assigned to taxa when they were discovered (all three bones were tentatively assigned to the Black-backed Jackal, Canis mesomelas), none of these classifications is thought valid as it is not currently accepted that Canid remains can be confidently assigned to taxa from isolated post-cranial bones.

Since ecomorphological studies of Canid bones have not been previously attempted, Meloro and Louys first examined a series of 92 radii belonging to 24 extant species of Canids in order to build up a data-set. This data-set was used to establish a statistical range for different Canid taxa thought to be reasonably reliable to genus level, as well as two sets of ecological data based upon prey size and habitat.

Measurement scheme for the canid radius, illustrated using a right radius of Canis lupus, in posterior (A), distallateral (B), proximal (C1) and distal (C2) posterior, proximal (D1) and distal (D2) lateralviews, proximal view of radius head (E), distal view of radius lower extremity (F). Meloro & Louys (2014).

Meloro and Louys established three prey size catagories within their modern data-set. Firstly a small-prey category that includes Foxes, small Jackals and similar species. Then a large-prey category that includes Wolves, African Hunting Dogs, Dingoes and Dholes (Indian Hunting Dogs). Finally a small-to-medium sized prey category that includes all other Canids.

They also established three categories based upon habitat classification; open for species where 60% or more of the species range exists in open grassland, closed for species that had 60% or more of their range within forested environments, and mixed for intermediate species.

Using this data-set Meloro and Louys are confident that the Koobi Fora specimen comes from a member of the genus Canis(which includes, Wolves, Coyotes, Jackals, Domestic Dogs and Dingos), and that it hunted small-to-medium prey in a mixed or open environment.

The proximal radius from Olduvai was predicted to have come from a member of the genus Lycaon, (the only extant member of which is the African Hunting Dog or Painted Dog, Lycaon pictus), and that it hunted small-to-medium prey in an open environment. This points to an animal closely related to the modern African Hunting Dog, but with a slightly different ecological niche; the modern Hunting Dog primarily hunts large prey in open environments (some recent studies have suggested that Hunting Dogs may have better hunting success in wooded environments, but that is thought to be because of human disturbance of their natural habitat).

A modern African Hunting Dog, Lycaon pictus. Dmitrij Rodionov/Wikimedia Commons.

However Meloro and Louys note that the analysis used on this specimen (which excludes measurements that it was not possible to take due to the partial nature of the bone) produced a different result for the Koobi Fora specimen, suggesting that it hunted large prey in a mixed environment, which implies caution needs to be used when interpreting partial Canid specimens in this way.

The second Olduvai specimen, the distal end of a right radius, was found to be a member of the genus Canis, and to have hunted small-to-medium prey in a mixed environment. The same analysis used on the Koobi Fora specimen suggested that it hunted small-to-medium prey in an open environment, consistent with the results achieved with the complete specimen.

All three specimens were originally referred to the Black-backed Jackal, Canis mesomelas, a small Canine (Canids are split into two subfamilies, the larger Canines or Dogs, and the smaller Vulpines, or Foxes, though all South American species, regardless of size, are thought to belong to the Vulpine group) hunting small-to-medium prey in open environments, and while later authorities have challenged this, most have suggested they belong to a ‘Jackal-lineage’. More recent studies based upon genetic analysis have shown that there is no single Jackal-lineage, but the various species described as Jackals are the result of convergent evolution in the genus Canis in response to similar environmental conditions. Morphometric analysis of the specimens suggests that two belong to the genus Canis, while one belongs to the closely related Lycoan, and that all hunted small-to-medium prey in mixed or open environments, consistent with Jackal-like behaviour.

See also…

A new species of Fox from the Pleisticene of Gauteng Province, South Africa.

Foxes (Vulpini) are a subgroup of the Dog Family, Canidae, found in North America, Eurasia and Africa (South American Foxes are a separate group, more closely related to True Dogs than to other Foxes). The...

The origin of domestic dogs.

 Dogs are our oldest domestic animal, and the only one which predates the adoption of agriculture. This has led to a great deal of study of the origin of domestic dogs over the years. Despite this we are still not entirely sure where dogs were first domesticated. We are now confident that domestic dogs are descended from a...

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Signs of malnutrition in a 1.5 million year old child's skull from the Olduvai Gorge.

The Olduvai Gorge is a ravine in the Great Rift Valley in northern Tanzania, which has produced numerous fossil and sub-fossil remains of early Humans and Hominins (anything more closely related to Humans than to Chimpanzees) dating from about 1.9 million years ago till around 17 000 years ago, and is considered to be one of the most important palaeoarchaeological sites known by those studying early Human evolution.

In a paper published in the journal PLoS One on 2 October 2012, a team of scientists led by Manuel Domínguez-Rodrigo of the Instituto de Evolución en África at the Museo de los Orígenes and the Department of Prehistory at Complutense University, both in Madrid, discuss the discovery of a partial skull of an infant in the Olduvai Gorge from about 1.5 million years ago, which shows signs of having died of a malnutrition related illness. Due to the fragmentary nature of the material it was not possible to tell the exact species of the individual.

Ectocranial (top right) and endocranial (top left) close-up views of the fossil, accompanied by magnifications of theporotic hyperostosis paleopathology as observed ectocranially (lower left) and edge-on at the diploic-table junction (lower right). Scale bars = 1 mm. Domínguez-Rodrigo et al. (2012)

The skull fragments come from an infant with an estimated age of about two years, suffering from a condition called porotic hyperostosis, a pathology associated with anemia. In porotic hyperostosis there is extensive marrow overgrowth within the skull bones, leading the flat outer layers of the bone to become thin and soft.

Scurvy and rickets can cause similar thinning of the skull, but scurvy causes only thinning of the outer bones without modification of the marrow chambers, whereas rickets can cause some enlargement to the marrow chambers, but not to the extent seen in the Olduvai fossil. Inflammatory diseases and infections can cause similar damage, but typically show several layers of damage and regrowth as the body fights the infection.

Iron-deficiency anemia is known to cause porotic hyperostosis, but not to the severe extent seen in this individual. Instead Domínguez-Rodrigo et al. suggest the infant was suffering from B₁₂ (cobalamin) and B₉ (folic acid) vitamin deficiencies. This suggests that malnutrition set in while the infant was still breast-feeding, probably due to a deficiency of meat in the mother's diet (modern humans, with sophisticated agriculture and wide trading networks can survive happily on vegetarian or even vegan diets, but hunter-gatherers in most climates usually need to rely on meat to obtain their full vitamin complement for at least part of the year.

A series of scanned sections through the skull, revealing the extent of the pathology. Domínguez-Rodrigo et al. (2012)

See also Skull closure in the Taung Infant, The earliest evidence of fire use from million year old sediments in Wonderwerk Cave, Northern Cape Province? The canine teeth of Australopithecus anamensis, Another look at the Canteen Kopje Skull and A re-evaluation of the Iwo Eleru skull.

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